"uuid","repository link","title","author","contributor","publication year","abstract","subject topic","language","publication type","publisher","isbn","issn","patent","patent status","bibliographic note","access restriction","embargo date","faculty","department","research group","programme","project","coordinates"
"uuid:668c33d5-b5ea-4f14-b205-396acf57389a","http://resolver.tudelft.nl/uuid:668c33d5-b5ea-4f14-b205-396acf57389a","RILEM TC 243-SGM report: grouting for historic architectural surfaces","Papayianni, Ioanna (Aristotle University of Thessaloniki); Bicer-Simsir, Beril (Getty Conservation Institute); Jornet, Albert (University of Applied Sciences of Southern Switzerland); Groot, C.J.W.P. (TU Delft Applied Mechanics); Valek, Jan (Czech Academy of Sciences); Bokan-Bosiljkov, Violeta (University of Ljubljana); van Hees, R.P.J. (TU Delft Heritage & Technology); Padovnik, Andreja (University of Ljubljana); Pachta, Vasiliki (Aristotle University of Thessaloniki)","","2023","Historic Structures are commonly coated with mortar layers (plasters, renders, flooring) for protection and decoration. These well finished architectural stratigraphic surfaces often suffer from deterioration, such as lack of adhesion or detachment between support and mortar layers and even between mortar layers. Grouting and filling voids between delaminated layers can be an effective intervention if the layers are compact. This paper deals with aspects pertinent to the selection, design and implementation of a grout for the in situ stabilization and preservation of historic architectural surfaces. It presents the methodological approach, in accordance with the conservation principles, including sections on diagnosis, study and assessment of the deterioration phenomena, definition of grout requirements, selection of proper ingredients for custom-made or commercial grouts, as well as making and testing trial mixes, field testing and Assessment of the effectiveness of grouting. The aim of this paper, that is elaborated in the frame of RILEM TC 243 SGM, is to serve as a guide for users of lime-based grouts for the reattachment and reinstatement of historical architectural surfaces.","Historic architectural surfaces; Lime-based grouts; Methodological approach; Multi-layers; Reattachments","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-07-01","","","Applied Mechanics","","",""
"uuid:3fad9926-2c4b-459e-8c7a-33f5d49c0fe5","http://resolver.tudelft.nl/uuid:3fad9926-2c4b-459e-8c7a-33f5d49c0fe5","RILEM TC 277-LHS report: properties of lime-based renders and plasters—discussion of current test methods and proposals for improvement","Veiga, Rosário (National Laboratory of Civil Engineering (LNEC)); Faria, Paulina (Nova University of Lisbon); van Hees, R.P.J. (TU Delft Heritage & Architecture); Stefanidou, Maria (Aristotle University of Thessaloniki); Maravelaki, Pagona Noni (Technical University of Crete); Ioannou, Ioannis (University of Cyprus); Theodoridou, Magdalini (Newcastle University); Bokan Bosilijkov, Violeta (University of Ljubljana); Bicer-Simsir, Beril (Getty Conservation Institute)","","2023","Renders and plasters have significant functions in buildings. Their functionality is closely related to their properties, which depend on the mortar itself, the application technology, the interaction with the environment and the substrate. There are many basic characteristics that influence the performance of renders and plasters; however, many of them are interrelated, thus the set of characteristics to be determined in each case is different, depending on the specific at each time use. These characteristics, their interrelations and the grouping of them are discussed and schematically described in the first and introductory section. Three groups are considered for renders and plasters: properties of fresh mortars; properties related to the hygric behaviour; and the mechanical behaviour. The properties of lime-based mortars measured in laboratory are highly affected by factors, such as: need of long time for development of representative values for prediction of their life-time behaviour, proper climatic conditions adequate for carbonation or/and hydration, sensitivity to the suction of water by the substrate. The last two factors—environment and substrate—have an important role for rendering and plastering with lime-based mortars, since both their exposed surfaces and the substrate areas they cover are large. Due to those specificities, the current test methods that have been mainly developed for cement-based mortars are not always fitted to characterize lime-based mortars, and in particular to assess lime-based renders and plasters. In section two the main characteristics and current standardized test methods are discussed based on experience in using them. Furthermore, needs of improvement are identified and changes are proposed, or, in some cases, new methods are outlined. Some of the most significant changes proposed are the possibility, as an option, to apply the mortar on a porous substrate, instead of moulding specimens in metallic moulds, together with modifications on curing conditions and times of mixing and testing. Additionally, test methods developed at laboratory to evaluate the cracking tendency due to restrained shrinkage and to determine the modulus of elasticity of under checking mortars are proposed, as well as alternative test methods for adhesion. In the case of testing other properties, smaller changes are proposed, in order for the standardized test methods to be adapted to the particularities of lime-based renders and plasters. As conclusions, in the third section, a synthesis of the proposed changes and complementary tests has been made in formulated tables, that could be considered as a first approach of adapted requirements for better performance of lime-based mortars for renders and plasters.","Fresh state behavior; Hygric behavior; Lime; Mechanical behaviour; Plaster; Render; Test","en","journal article","","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care. Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","2023-10-06","","","Heritage & Architecture","","",""
"uuid:2a9efbc4-5798-467e-a6ca-56eae11a612f","http://resolver.tudelft.nl/uuid:2a9efbc4-5798-467e-a6ca-56eae11a612f","Recommendation of RILEM TC 271-ASC: New accelerated test procedure for the assessment of resistance of natural stone and fired-clay brick units against salt crystallization","Lubelli, B. (TU Delft Heritage & Architecture); Rörig-Daalgard, I. (Technical University of Denmark); Aguilar, A. M. (ETH Zürich); Aškrabić, M. (University of Belgrade); Beck, K. (Université d'Orléans); Bläuer, C. (Bläuer Conservation Science Sarl); Cnudde, V. (Universiteit Gent); D’Altri, A. M. (University of Bologna); van Hees, R.P.J. (TU Delft Heritage & Architecture); Kamat, Ameya (TU Delft Heritage & Architecture)","","2023","This recommendation is devoted to testing the resistance of natural stone and fired-clay brick units against salt crystallization. The procedure was developed by the RILEM TC 271-ASC to evaluate the durability of porous building materials against salt crystallization through a laboratory method that allows for accelerated testing without compromising the reliability of the results. The new procedure is designed to replicate salt damage caused by crystallization near the surface of materials as a result of capillary transport and evaporation. A new approach is proposed that considers the presence of two stages in the salt crystallization test. In the first, the accumulation stage, salts gradually accumulate on or near the surface of the material due to evaporation. In the second, the propagation stage, damage initiates and develops due to changes in moisture content and relative humidity that trigger salt dissolution and crystallization cycles. To achieve this, two types of salt were tested, namely sodium chloride and sodium sulphate, with each salt tested separately. A methodology for assessing the salt-induced damage is proposed, which includes visual and photographical observations and measurement of material loss. The procedure has been preliminarily validated in round robin tests.","Recommendation; RILEM TC 271-ASC; Salt crystallization test; Sodium chloride; Sodium sulfate","en","journal article","","","","","","","","","","","Heritage & Architecture","","",""
"uuid:4f11d44c-d499-4153-9bfc-26166482fd20","http://resolver.tudelft.nl/uuid:4f11d44c-d499-4153-9bfc-26166482fd20","RILEM TC 277-LHS report: lime-based mortars for restoration–a review on long-term durability aspects and experience from practice","Groot, C.J.W.P. (TU Delft Applied Mechanics); Veiga, Rosario (National Laboratory of Civil Engineering (LNEC)); Papayianni, Ioanna (Aristotle University of Thessaloniki); van Hees, R.P.J. (TU Delft Heritage & Technology); Secco, Michele (Università degli Studi di Padova); Alvarez, José I. (University of Navarra); Faria, Paulina (Nova University of Lisbon); Stefanidou, Maria (Aristotle University of Thessaloniki)","","2022","For conservation interventions of historic masonry generally lime-based mortars such as pure air lime mortars, lime-pozzolan mortars, natural hydraulic lime mortars and ternary mortars (lime-pozzolan-cement) are used. The main reason is that their hygric and mechanical (strength and ductility) performance are easy to adapt to most existing historic masonry (compatibility requirements). Although the basic appropriateness of lime-based mortars for restoration is undisputed, there are also some limitations in the application of these mortars. In this report a review is given of the theoretical backgrounds and further of laboratory research developments in the field of lime-based binders and mortars over the past decades. Furthermore, practical experiences in positive and negative sense (damage cases) are elaborated. Drawbacks and points of attention are being dealt with, which are essential for a durable application of lime-based mortars for the conservation of historic masonry. In general, it is concluded that points of attention should be addressed through a thorough evaluation of their potential and through testing of their suitability. For these mortars, even more than for modern cement-based mortars, specifically, environmental exposure conditions and application conditions should be considered.","Binding mechanism; Damage cases; Lime-based mortars; Long-term durability; Practice","en","journal article","","","","","","","","","","","Applied Mechanics","","",""
"uuid:7980267b-9a5f-4122-a269-407ff8e72d27","http://resolver.tudelft.nl/uuid:7980267b-9a5f-4122-a269-407ff8e72d27","Integrated Conservation Strategies In The Netherlands","Naldini, S. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology); van der Grijp, Ernst (Monumentenwacht Gelderland)","Roca, P. (editor); Pelà, L. (editor); Molins, C. (editor)","2021","In the Netherlands a program for the enhancement of quality in the restoration of monumental buildings is presently carried out, stimulated by national authorities and coordinated by the foundation ERM. Guidelines are issued by the branches involved, from architects to masons, under guidance of an experts’ committee, to perform interventions on monuments and assess them. The aim of this paper is to discuss the contributions to the program offered by different actors active in the field of conservation, the existing synergies and the potential of using a common language and approach. These are needed to facilitate communication and exchange knowledge. The use of the terminology of MDCS (Monument Diagnosis and Conservation System) can help create a community of stakeholders. Sharing the damage terminology and methodology can help achieving a clear and systematic assessment of damage and its causes. It can further improve the communication among all stakeholders, including owners and laymen, stimulating cooperation, and can allow monitoring of damage and interventions.","Monumental Buildings; Visual Inspection; Quality in Restoration; Terminology","en","conference paper","International Centre for Numerical Methods in Engineering, CIMNE","","","","","","","","","","Heritage & Technology","","",""
"uuid:5800403b-1069-405d-b6e8-5157be940e78","http://resolver.tudelft.nl/uuid:5800403b-1069-405d-b6e8-5157be940e78","Vochtschade na brand: De casus van de Elleboogkerk in Amersfoort","Lubelli, B. (TU Delft Heritage & Architecture); van Hees, R.P.J. (TU Delft Heritage & Technology; R2 Monumentenadvies)","","2021","Het blussen van een brand gaat gepaard met een grote hoeveelheid water die in het metselwerk van een gebouw binnendringt; daarnaast duurt het vaak ook nog lange tijd voor een gebouw weer waterdicht kan worden gemaakt. Dit kan een hoog vochtgehalte in de muren veroorzaken, met alle daaraan verbonden problemen, zoals zouttransport, zout- en vorstschade en biologische groei. In dit artikel wordt de casus van de Neo-classicistische Elleboogkerk te Amersfoort besproken, waarvan de kapconstructie in 2007 door een brand werd verwoest. Naast directe schade door de brand aan het gebouw en de daarin aanwezige museale collectie, ontstond er ook vervolgschade als gevolg van vocht. Onderzoek toonde aan dat een hoog vochtgehalte in de muren, in de nasleep van de brand, de oorzaak is geweest van het loskomen van het nieuwe pleisterwerk, binnen enkele weken nadat dit was aangebracht. Daarnaast maakte het onderzoek het mogelijk om, op basis van het gemeten zoutgehalte in de muur, het risico voor het verder ontstaan van schade in te schatten en advies te geven over het wel of niet vervangen van de (nog) niet beschadigde delen van het renovatiepleisterwerk.","moisture damage; plaster","nl","book chapter","WTA Nederland - Vlaanderen","","","","","Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.","","","","","Heritage & Architecture","","",""
"uuid:390e81d4-175b-42b7-8867-8a8dc76b9719","http://resolver.tudelft.nl/uuid:390e81d4-175b-42b7-8867-8a8dc76b9719","Characterization and compatibility assessment of commercial stone repair mortars","Lubelli, B. (TU Delft Heritage & Technology); Nijland, Timo G. (TNO); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","","2021","Compatibility of repair materials in conservation is a widely desired goal, but difficult to achieve. In this research, the compatibility of four commercial stone repair mortars, commonly used in conservation practice in the Netherlands and neighbouring countries, is discussed. In order to do so, they have been characterized in laboratory. The composition of the repair mortars, their content of soluble salts, porosity and pore size distribution, hygric dilation and flexural and compressive strength were measured. The effect of curing was assessed by comparing specimens cured in laboratory and under outdoor conditions. The effect of 3 years outdoor exposure on the curing and weathering of the mortars was evaluated. The results show that the composition of the selected mortars varies significantly, even though, based on their technical information sheets, they appeared to be similar. Consequently, their moisture transport properties differ significantly. As expected, both the type of binder and the porosity were shown to affect the mechanical properties of the mortar: the mortar based on an inorganic polymer binder showed the highest mechanical strength; the most porous, lime- or lime-cement-based mortars, showed the lowest mechanical strength. Based on compatibility criteria defined in literature and the results obtained in this research, an attempt was made to assess the technical compatibility of the selected mortars with building stones commonly used in the Netherlands. It was found that some requirements are hard to be fulfilled and not all requirements can be fulfilled at the same time. Besides, technical sheets of commercial mortars are often incomplete; therefore repair mortars can hardly be selected based only on the properties reported by the producers.","Compatibility; Microstructure; Porosity; Stone repair mortars; Strength","en","journal article","","","","","","","","","","","Heritage & Technology","","",""
"uuid:2c8105b9-b262-423c-a21c-7072164160d7","http://resolver.tudelft.nl/uuid:2c8105b9-b262-423c-a21c-7072164160d7","Indoor climate in the Rietveld Schröder house","Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology)","van Thoor, Marie-Therese (editor)","2019","The Rietveld Schröder House is not only an icon of Dutch architecture, but also a museum welcoming about 18,000 visitors each year. The unusual experimental character of the construction and the fact that the house is open to the public
can be expected to affect the indoor climate and to pose some risks for the conservation of the building and the furniture. In order to assess possible risks related to the indoor climate and, if necessary, take measures, a monitoring of the indoor climate was carried out in 2017.","history; heritage","en","book chapter","Delft University of Technology","","","","","","","","","","Heritage & Technology","","",""
"uuid:900cae6c-4179-437f-8363-62ad4bdd8bbb","http://resolver.tudelft.nl/uuid:900cae6c-4179-437f-8363-62ad4bdd8bbb","Recommendation of RILEM TC 243-SGM: Functional requirements for surface repair mortars for historic buildings","Válek, Jan (Czech Academy of Sciences); Hughes, John J. (University of the West of Scotland); Pique, Francesca (SUPSI); Gulotta, Davide (Politecnico di Milano); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO); Papayiani, Ioanna (Aristotle University of Thessaloniki)","","2019","Surface repair mortars are used for the compensation, or repair, of lost portions of surface materials in historic masonry buildings. It is recommended that their design and application should be performed in a wider context of conservation values related decision making, to prioritise preservation of original fabric, authenticity of approach and maintenance of integrity, and not just on technical principles alone. However, a technical context for their design does exist, that requires understanding of the properties of the substrate that they will be applied onto, and adherence to minimum aesthetic (colour and texture) requirements. The principles of physical, mechanical and chemical compatibility of repair apply and the attributes of the repair mortar should be carefully matched to the substrate alongside a sacrificial behaviour (not more durable than the material being replaced). Guidance is given on the design, application and the functional requirements that must be met when using surface repair mortars.","Functional requirements; Historic masonry; Mortar; Surface repair","en","journal article","","","","","","Accepted Author Manuscript","","2020-02-13","","","Heritage & Technology","","",""
"uuid:5606a890-5bdd-43e6-8577-e0312c39d8dd","http://resolver.tudelft.nl/uuid:5606a890-5bdd-43e6-8577-e0312c39d8dd","Effect of mixed in crystallization modifiers on the resistance of lime mortar against NaCl and Na2SO4 crystallization","Granneman, S.J.C. (TU Delft Heritage & Technology); Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","","2019","Weathering of porous building materials caused by the crystallization of soluble salts is a ubiquitous problem in the built cultural heritage. Especially lime-based mortars are susceptible to salt decay, due to both their bimodal pore size distribution and low mechanical strength. The addition of crystallization modifiers to mortars during mixing may confer them an improved resistance to salt decay. In this research, lime-based mortars additivated with ferrocyanide or borax (modifiers for sodium chloride and sodium sulfate, respectively) were prepared. An accelerated salt crystallization test was carried out to assess the effect of the modifiers on the salt resistance of the mortars. The development of damage was assessed by visual and photographical observations and by quantifying the salt and material loss. At the end of the test, SEM observations were performed on the surface and cross-section of the specimens, to study the effect of the modifiers on the crystallization habit of the salts. The ferrocyanide and borax additivated mortars showed a considerably improved durability with respect to salt crystallization damage. Both modifiers altered the growth morphology of the salt crystals inside the pores of the mortars.","Crystallization modifiers; Lime mortar; Salt crystallization; Salt damage; Sodium chloride; Sodium sulfate","en","journal article","","","","","","Accepted Author Manuscript","","2020-11-08","","","Heritage & Technology","","",""
"uuid:d2f08e2d-109e-40ca-8f30-6ded99999fbf","http://resolver.tudelft.nl/uuid:d2f08e2d-109e-40ca-8f30-6ded99999fbf","Hydrofoberen: duurzaamheid in de praktijk","Quist, W.J. (TU Delft Heritage & Technology); van Dam, J.J.E. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology)","Nijland, T.G. (editor)","2018","Naar aanleiding van het historisch georiënteerde onderzoek naar oppervlaktebehandelingen (Nijland & Quist 2018) en het onderzoek naar het hervoegen van gehydrofobeerd metselwerk, beide uitgevoerd binnen de samenwerking tussen TNO, RCE en TU Delft in MonumentenKennis, ontstond het idee om aan de hand van een aantal casussen te kijken naar de duurzaamheid van hydrofoberingen. Voor de keuze van de casussen is teruggegrepen op twee onderzoeken/publicaties uit de jaren ’90 van de vorige eeuw waarin de prestatie van hydrofoberingen werd onderzocht (Van Hees & Koek 1994, Van Hees et al. 1998). Een aantal objecten dat in deze studies is onderzocht is in juni 2018 opnieuw bezocht en bij een deel van deze objecten zijn in november 2018 Karstenbuismetingen verricht om de waterabsorptie van de (bak)steen en het voegwerk te meten.","","nl","conference paper","MonumentenKennis","","","","","","","","","","Heritage & Technology","","",""
"uuid:260185a6-5a46-4bbd-9742-e50ed57541e8","http://resolver.tudelft.nl/uuid:260185a6-5a46-4bbd-9742-e50ed57541e8","Effectiveness of methods against rising damp in buildings: Results from the EMERISDA project","Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology); Bolhuis, J. (Architektenburo Veldman)","","2018","Rising damp is a recurrent hazard to ancient buildings in Europe and its relevance is expected to increase in the future, due to climate changes. The presence of rising damp in walls does not only create an unpleasant climate in buildings, but it also enhances damage processes such as frost action, salt crystallization and biological growth, with possible consequences on the health of the inhabitants. The relevance of this problem is reflected by the large variety of products on the market. The wide and differentiated offer and the scarce scientific information on the effectiveness of the methods make it difficult, (even) for professionals working in the field, to choose a suitable intervention on a sound basis. The JPICH-financed project EMERISDA (2014–2017) [1] aimed at evaluating the effectiveness of different intervention methods against rising damp. The project involved universities, research institutes, heritage agencies and companies (producers and contractors) in Belgium (BBRI, co-ordinator), Italy (CNR-ISAC, Universita’ Ca’ Foscari Venezia, Restauri Speciali s.r.l., Diasen s.r.l.) and The Netherlands (Delft University of Technology and the Cultural Heritage Agency of the Netherlands). The research methodology included the use of an on-line questionnaire and experimental research in laboratory, on scale models and on-site. Both traditional methods, such as chemical injection, and more recent techniques, such as the so-called “electro-physical” methods have been investigated. [2] The following results of the EMERISDA project are presented in this paper: - Results from on-line questionnaire.- Definition of an experimental procedure for the assessment of the presence of rising damp and of the effectiveness of the intervention.- Prototype of decision support tool, which provides insight into the feasibility and risks of existing methods against rising damp and supports actors involved in conservation in the choice and application of the methods against rising damp.","Assessment of rising damp; Decision support tool; Intervention against rising damp; Rising damp","en","journal article","","","","","","Accepted Author Manuscript","","2019-05-09","","","Heritage & Technology","","",""
"uuid:eb9f7738-1596-4359-9cf8-9c58aba09cde","http://resolver.tudelft.nl/uuid:eb9f7738-1596-4359-9cf8-9c58aba09cde","Een plaag van alle tijden: zout: Over oude en toekomstige schade, oud en toekomstig onderzoek","Nijland, T.G. (TNO); Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology)","Nijland, T.G. (editor)","2018","In deze bijdrage wordt nader ingegaan op de achtergronden van zoutschade, de vraag of we er in de toekomst meer last van zullen krijgen, en op oud, nieuw en gewenst onderzoek.","","nl","conference paper","MonumentenKennis","","","","","","","","","","Heritage & Technology","","",""
"uuid:6865f1b2-5fea-4723-b305-eaba79da1bd9","http://resolver.tudelft.nl/uuid:6865f1b2-5fea-4723-b305-eaba79da1bd9","Nieuwe testmethoden voor injectieproducten tegen optrekkend vocht","van Hees, R.P.J. (TU Delft Heritage & Technology; TNO); Lubelli, B. (TU Delft Heritage & Technology; TNO); Hacquebord, A. (TU Delft Education and Student Affairs)","Nijland, T.G. (editor)","2018","Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend Injectie van chemische producten is wellicht de meest verbreide methode om optrekkend vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om vocht te bestrijden. Bij de meerderheid van deze producten gaat het om hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen hydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffenhydrofobeermiddelen, ofwel op basis van koolwaterstoffen, of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende of (en dat in toenemende mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare mate) met water als oplosmiddel. In hun oorspronkelijke vorm ging het om vloeibare producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in producten, maar er is de laatste jaren een groeiend aantal producten in de vorm van de vorm van de vorm van de vorm van de vorm van de vorm van de vorm van de vorm van crèmecrème crèmecrèmes.
Uit de praktijk komen tegengestelde berichten met betrekking tot de effectiviteit van de injecties; vaak ontstaat een controverse tussen gebouweigenaar en uitvoerend bedrijf over de werkzaamheid van het product. Soms wordt daarbij de noodzakelijk lange droogtijd voor een natte muur als argument gebruikt om een tekortschietende behandeling te camoufleren. In andere gevallen is het onduidelijk of de injectie danwel een gelijktijdig aangebrachte restauratiepleister verantwoordelijk is voor een (in elk geval visuele) verbetering.
In deze bijdrage wordt onderzoek beschreven gericht op het ontwikkelen van een methode waarmee op eenvoudige en snelle wijze de werkzaamheid van een product kan worden aangetoond, zowel in de praktijk als in het laboratorium.
Een interessant nevenaspect van het onderzoek was overigens dat diverse essentiële factoren die bepalend zijn voor de effectiviteit van injectieproducten duidelijk zijn geworden. In deze bijdrage zal de snelle methode voor de praktijk centraal staan.","","nl","conference paper","MonumentenKennis","","","","","","","","","","Heritage & Technology","","",""
"uuid:b4200921-51ce-4985-a685-fa3625e39964","http://resolver.tudelft.nl/uuid:b4200921-51ce-4985-a685-fa3625e39964","Kalkmortel met een snufje chemie","Granneman, S.J.C. (TU Delft Heritage & Technology); Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology)","Nijland, T.G. (editor)","2018","In deze bijdrage worden de belangrijkste bevindingen gerelateerd aan het effect van toevoeging van de modificatoren op morteleigenschappen en op de duurzaamheid van de mortels gerapporteerd. Allereerst wordt er een experiment beschreven waarin wordt getest of de effectiviteit van borax wordt beïnvloed door het carbonatatieproces. Vervolgens worden de effecten van de modificatoren op morteleigenschappen zoals verwerkbaarheid, waterabsorptie en droging, en buig- en druksterkte gerapporteerd. Als laatste wordt de weerstand van de mortels met modificatoren tegen zoutschade bediscussieerd aan de hand van resultaten van een versnelde zoutkristallisatietest.","","nl","conference paper","MonumentenKennis","","","","","","","","","","Heritage & Technology","","",""
"uuid:cfc66546-dac2-45f9-97ff-6b2ca2307c1c","http://resolver.tudelft.nl/uuid:cfc66546-dac2-45f9-97ff-6b2ca2307c1c","Characterization of lime mortar additivated with crystallization modifiers","Granneman, S.J.C. (TU Delft Heritage & Technology); Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","","2018","Additivating mortars with crystallization modifiers is a novel approach to mitigate salt crystallization damage in historic masonry. Once verified the effectiveness of crystallization modifiers in bulk solution, the next step consists in verifying whether: (i) modifiers are still effective when mixed in mortar and going through the carbonation process and (ii) modifiers alter any mortar properties which might limit their application. This research addresses these issues for sodium ferrocyanide and borax, modifiers for sodium chloride, and sodium sulfate, respectively. Several experimental techniques have been applied to elucidate these questions. The results show that the selected modifiers are still able to alter the salt crystallization after going through the carbonation process of the mortar. Besides, no major effects of the modifiers on the fresh and hardened mortar properties were observed. It can therefore be concluded that there are no restraints for the future use of these crystallization modifiers in restoration mortars.","Borax; ferrocyanide; lime mortar; mixed-in crystallization modifiers; mortar properties; salt decay","en","journal article","","","","","","","","","","","Heritage & Technology","","",""
"uuid:482938a4-5338-488e-847e-44927dd9add9","http://resolver.tudelft.nl/uuid:482938a4-5338-488e-847e-44927dd9add9","Optrekkend vocht: Hoe kiest u een geschikte interventie ?","Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology); Bolhuis, J. (Architektenburo Veldman, Rietbroek, Smit)","Nijland, T.G. (editor)","2018","Optrekkend vocht is een vaak voorkomend fenomeen in gebouwen. Vooral oude gebouwen die geen waterkerende laag (zoals bijvoorbeeld een trasraam) hebben, lijden aan dit probleem. De relevantie van optrekkend vocht blijkt ook uit het grote aanbod van producten voor het bestrijden van dit probleem. Het grote, gevarieerde aanbod en de beperkte literatuur over de effectiviteit van de bestrijdingsmethoden maken het moeilijk voor mensen werkzaam in de praktijk om een keuze te maken tussen de verschillende methoden.
Binnen het project EMERISDA, gefinancierd door het Europese Joint Program Initiative Cultural Heritage (JPI-CH), is onderzoek uitgevoerd naar de effectiviteit van de verschillende methoden met als uiteindelijke doel een beslissingssysteem te ontwikkelen ter ondersteuning van de praktijk.
Het onderzoek bestond uit literatuuronderzoek, een online enquête om de tevredenheid van de gebruiker (gebouweigenaren en instanties werkzaam in de conservering van cultureel erfgoed) te meten en experimenteel onderzoek in het laboratorium en in situ (aan schaalmodellen en aan gebouwen). De resultaten van het project zijn samengebracht in een digitaal beslissingssysteem. Dit systeem is ontwikkeld om gebruikers te ondersteunen in het vaststellen van de aanwezigheid van optrekkend vocht in gebouwen en in het kiezen van een geschikte interventie.","","nl","book chapter","MonumentenKennis","","","","","","","","","","Heritage & Technology","","",""
"uuid:3543f55a-cc44-4a9a-b457-5315b06b963e","http://resolver.tudelft.nl/uuid:3543f55a-cc44-4a9a-b457-5315b06b963e","New test methods to verify the performance of chemical injections to deal with rising damp","van Hees, R.P.J. (TU Delft Heritage & Technology; TNO); Lubelli, B. (TU Delft Heritage & Technology; TNO); Hacquebord, A. (TU Delft Education and Student Affairs; TNO)","","2018","The injection of chemical products, meant to penetrate in the capillaries of the materials composing an affected wall, is perhaps the most diffused method to deal with rising damp. The majority of these chemical products are hydrophobic treatments; they can be either solvent-based or (increasingly) water-based. Traditionally, these products are liquid. In the last years however, a tendency towards the use of cream-like products can be observed. From practice, quite contradictory opinions arrive with respect to the effectiveness of injections and quite often disputes develop between building owner and executing contractor on the performance of the treatment. Sometimes the slow drying of humid walls is used to cover a failing treatment; in other cases, it is not clear whether the injection or a simultaneously applied restoration plaster is responsible for a visual improvement. Research was performed in order to establish a method to evaluate the effectiveness of injection methods in a simple and quick way, both for assessing performance in practice and for use in laboratory. Interesting side effect of the research program was that also several essential parameters, influencing the effectiveness of chemical products, became evident. In this article, focus will be on the quick assessment method for practice.","Damp-proof course; Injection products; Rising damp; Test method","en","journal article","","","","","","Accepted Author Manuscript","","2019-05-09","","","Heritage & Technology","","",""
"uuid:46e09279-7c93-4a5a-a14e-36765367a6b4","http://resolver.tudelft.nl/uuid:46e09279-7c93-4a5a-a14e-36765367a6b4","Towards a more effective and reliable salt crystallization test for porous building materials: state of the art","Lubelli, B. (TU Delft Heritage & Technology); Cnudde, Veerle (Universiteit Gent); Diaz-Goncalves, Teresa (National Laboratory of Civil Engineering (LNEC)); Franzoni, Elisa (University of Bologna); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO); Ioannou, Ioannis (University of Cyprus); Menendez, Beatriz (Université de Cergy-Pontoise); Nunes, Cristiana (Czech Academy of Sciences and Arts); Siedel, Heiner (Technische Universität Dresden); Stefanidou, Maria (Aristotle University of Thessaloniki); Verges-Belmin, Veronique (Laboratoire de Recherche des Monuments Historiques); Viles, Heather (University of Oxford)","","2018","The durability of building materials with respect to salt crystallization is commonly determined by accelerated weathering tests, carried out in the laboratory. An effective laboratory weathering test should assess the durability and, in the case of conservation of historic buildings, the compatibility of repair materials with those existing. Besides, the test should provide reliable results within a reasonable period of time, accelerating the deterioration process without however altering its mechanism. Despite several national and international standards, recommendations and guidelines, a commonly accepted testing protocol does not yet exist. Researchers often develop and apply their own procedure, a fact that complicates comparison between different studies. The RILEM Technical Committee 271 ASC has been set up with the scope of developing improved test procedures for the assessment of the behaviour of materials under the influence of salt crystallization, which should overcome the limitations of existing standards and recommendations. This paper constitutes one of the first results of the work of the Technical Committee. It critically reviews the literature on salt crystallization tests, identifies advantages and limitations of the several test protocols and provides new ideas for the development of improved salt crystallization procedures.","Literature review; Porous materials; RILEM; Salt crystallization test; Salt damage","en","journal article","","","","","","","","","","","Heritage & Technology","","",""
"uuid:038f0cfa-cbb7-4581-b40c-54f0045685ba","http://resolver.tudelft.nl/uuid:038f0cfa-cbb7-4581-b40c-54f0045685ba","Mitigating salt damage in lime-based mortars with mixed-in crystallization modifiers","Granneman, S.J.C. (TU Delft Heritage & Technology); Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","Laue, S. (editor)","2017","This paper presents the most important results of a research project which
focused on the use of crystallization modifiers mixed in lime mortar to mitigate
salt crystallization damage. The research focused on two of the most damaging
salts, sodium chloride and sodium sulfate, and suitable crystallization modifiers (sodium ferrocyanide and borax). We report the major findings related to the effectiveness of the modifiers when mixed in the mortar, and the results of characterization of the additivated mortars in comparison with reference mortars. Moreover, the durability of the developed mortars to salt decay is discussed, based on the results of an accelerated salt weathering test carried out in laboratory. No major effects of the modifiers on the fresh and hardened mortar properties were observed which might restrain the application of crystallization modifiers in restoration mortars. Additionally, the mortars with mixed-in modifiers showed a considerable improvement of the salt resistance when compared to reference mortars. Considering these results an outlook for future research pathways is given.","crystallization modifiers; self-healing; lime mortar","en","conference paper","Fachhochschule Potsdam","","","","","This paper was previously presented at and published in the Proceedings of the 4th WTA International PhD Symposium, 13-16 September, Delft, The Netherlands. The paper was reproduced for the SWBSS conference with permission of the organizing committee.","","","","","Heritage & Technology","","",""
"uuid:7aa1ce87-eefd-41a2-b25d-2dc41dc76bb5","http://resolver.tudelft.nl/uuid:7aa1ce87-eefd-41a2-b25d-2dc41dc76bb5","Bilateral collaboration in built heritage material research and resource maintenance supportive to smart and sustainable cities","Quist, W.J. (TU Delft Heritage & Technology); Clarke, Nicholas (TU Delft Teachers of Practice; University of Pretoria); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","Conradie, D.C.U. (editor); du Plessis, C. (editor); van den Dobbelsteen, A.A.J.F. (editor)","2017","Built heritage contains value on many scales. On the most basic level it represents the investment of building materials following a constructional logic. As the use of once-predominant materials goes out of fashion due to changing technological regimes and architectural styles, knowledge about them is lost. Yet retaining and maintaining their embodied energies in place is an important aspect of resource efficiency. Waste management, circularity and in situ retention of built fabric as useful resource is a sustainability ambition for built environment systems in general and for heritage conservation in particular.
The Netherlands and South Africa have a long historic association. Therefore commonality is to be found in the constructional logic of the shared built heritage of both countries. This historic association brought the transfer of construction components through material streams as well as the transfer of knowledge from the Netherlands to climatically different South Africa. It is expected that the historic transfer of knowledge and materials from the Netherlands to South Africa has led to climate adaptive and practical alterations of Dutch principles. These hold potential to shed valuable new light on retaining built fabric in the Netherlands average temperatures are increasing. Dutch knowledge on maintenance and repair can augment the rather scant South African body of knowledge on material maintenance and repair.
This paper will explore the possibilities for collaborative research on material maintenance and repair from the perspective of Smart and Sustainable Cities, identifying opportunities for collaboration in the commonalities that exists between the Netherlands and South Africa.","maintenance; material resources; repair; shared built heritage; the Netherlands-South Africa","en","conference paper","CSIR","","","","","","","","","","Heritage & Technology","","",""
"uuid:1bbc40eb-06b7-4458-8e01-298266b2fd22","http://resolver.tudelft.nl/uuid:1bbc40eb-06b7-4458-8e01-298266b2fd22","Mitigating salt damage in lime-based mortars with mixed-in crystallization modifiers","Granneman, S.J.C. (TU Delft Heritage & Technology); Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","Quist, W.J. (editor); Granneman, S.J.C. (editor); van Hees, R.P.J. (editor)","2017","This paper describes some of the most important results of a four year PhD research on the use of crystallization modifiers mixed in lime mortar to mitigate salt crystallization damage. The research focused on two of the most damaging salts, sodium chloride and sodium sulfate, and suitable crystallization modifiers (sodium ferrocyanide and borax). We report the major findings related to the effectiveness of the modifiers when mixed in the mortar, and the results of characterization of the additivated mortars in comparison with reference mortars. Moreover, the durability of the developed mortars to salt decay is discussed, based on the results of an accelerated salt weathering test carried out in laboratory. No major effects of the modifiers on the fresh and hardened mortar properties were observed which might restrain the application of crystallization modifiers in restoration mortars. Additionally, the mortars with mixed-in modifiers showed a considerable improvement of the salt resistance when compared to reference mortars. Considering these results an outlook for future research pathways is given.","Crystallization Modifiers; Self-Healing; Lime Mortar","en","conference paper","WTA Nederland - Vlaanderen","","","","","","","","","","Heritage & Technology","","",""
"uuid:8dbf49ee-858a-4b26-826f-82bcf7bb9ec4","http://resolver.tudelft.nl/uuid:8dbf49ee-858a-4b26-826f-82bcf7bb9ec4","Effect of borax on the wetting properties and crystallization behavior of sodium sulfate","Granneman, S.J.C. (TU Delft Heritage & Technology); Shahidzadeh, Noushine (Universiteit van Amsterdam); Lubelli, B. (TU Delft Heritage & Technology; TNO); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","","2017","Borax has been identified as a possible crystallization modifier for sodium sulfate. Understanding the effect of borax on factors influencing transport and crystallization kinetics of sodium sulfate helps to clarify how this modifier might limit crystallization damage. It has been observed that the addition of borax to sodium sulfate solutions has no influence on the wetting properties (contact angle on glass, surface tension, or evaporation rate) and therefore will not influence solution transport. Additionally, the influence of borax on the crystallization kinetics of sodium sulfate was studied under controlled environmental conditions. This was carried out in mixtures in glass microcapillaries, and sequentially in droplets on glass plates. Under the here studied precipitation conditions, the addition of borax has no influence on the supersaturation ratio at the onset of crystallization, but it significantly affects the crystallization pattern of anhydrous sodium sulfate crystals (thenardite). Using RAMAN spectroscopy, two different hydrates of borax were identified after precipitation, depending on the initial concentration of the solution. Each hydrate has a different effect on the subsequent crystallization of sodium sulfate. The decahydrate polymorph of borax leads to the precipitation of hydrated sodium sulfate crystals (mirabilite) and the pentahydrate form favors the precipitation of the anhydrous sodium sulfate crystals (thenardite) with an altered crystal habit. Using X-ray diffraction, overdevelopment of the (111), (131), (222) and (153) faces of thenardite was identified. Additionally, the ratios between several peaks are reversed. These results confirm the deviation of the grown crystals of the equilibrium crystal shape of thenardite as observed with optical microscopy.","","en","journal article","","","","","","Accepted Author Manuscript","","2018-01-19","","","Heritage & Technology","","",""
"uuid:1530635f-74e2-457f-b317-177e192670c3","http://resolver.tudelft.nl/uuid:1530635f-74e2-457f-b317-177e192670c3","Consolidation of Renders and Plasters (RILEM TC 243-SGM)","Van Hees, R.P.J.; Veiga, R.; Slíková, Z.","","2016","","","en","journal article","","","","","","","","","Architecture and The Built Environment","AE+T","","","",""
"uuid:4f0911c4-0d4b-41c0-862d-8ce904dfb90a","http://resolver.tudelft.nl/uuid:4f0911c4-0d4b-41c0-862d-8ce904dfb90a","Optimization of nanolime solvent for the consolidation of coarse porous limestone","Borsoi, G. (TU Delft Heritage & Technology); Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology); Veiga, Rosário (National Laboratory of Civil Engineering (LNEC)); Santos Silva, António (National Laboratory of Civil Engineering (LNEC))","","2016","The potentialities of nanomaterials for applica- tion in the field of conservation have been widely investi- gated in the last two decades. Among nanomaterials, nanolimes, i.e., dispersions of lime nanoparticles in alco- hols are promising consolidating products for calcareous materials. Nanolimes are effective in recovering the very superficial loss of cohesion of decayed materials, but they do not always provide sufficient mass consolidation. This limitation is mainly related to the deposition of the nanoparticles nearby the surface of the material. Experi- mental research has been set up with the aim of improving the in-depth deposition of lime nanoparticles. Previous research by the authors has shown that nanolime deposition within a substrate can be controlled by adapting the nanolimes properties (kinetic stability and evaporation rate) to the moisture transport behavior of the substrate. Nanolime properties can be modified by the use of different solvents. In this research, nanolime dispersions have been further optimized for application on Maastricht limestone, a coarse porous limestone. Firstly, nanolimes were syn- thesized and dispersed in ethanol and/or water, both pure and mixed in different percentages. Subsequently, based on the kinetic stability of the nanolime dispersions, the most promising solvent mixtures were selected and applied on the limestone. The deposition of lime nanoparticles within the limestone was studied by phenolphthalein test, optical microscopy and scanning electron microscopy. The results confirm that nanolime dispersed in a mixture of ethanol (95 %) and water (5 %) can guarantee a better nanoparti- cles in-depth deposition within coarse porous substrates, when compared to dispersions in pure ethanol.","","en","journal article","","","","","","","","","","","Heritage & Technology","","",""
"uuid:dd49ddba-6db1-44e1-93d2-a844acb85a41","http://resolver.tudelft.nl/uuid:dd49ddba-6db1-44e1-93d2-a844acb85a41","""Electro-physical"" methods to stop rising damp: Assessment of the effectiveness in two case studies","Lubelli, B. (TU Delft Heritage & Technology; TNO); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO); Miedema, L. (TU Delft Heritage & Technology); Fugazzotto, M. (ISAC-CNR); Sardella, A. (ISAC-CNR); Bonazza, A. (ISAC-CNR)","Rörig-Dalgaard, Inge (editor); Ioannou, Ioannis (editor)","2016","Rising damp is a recurrent hazard to ancient buildings and its relevance is expected to increase in future, due to climate changes. In spite of the large diffusion of methods and products to stop rising damp, scientific literature on their effectiveness in the field is often scarce and not conclusive. This is particularly true for recent solutions; examples are the “electro-physical” methods, which are currently flourishing in many countries. These methods are often lacking a scientifically based proof of their working principles and effectiveness. Within the JPI-CH project EMERISDA, the effectiveness of two different commercial electro-physical devices was investigated in two case-studies. The devices were positioned in such a way as to include humid walls under the influence of the device as well as humid walls, comparable in orientation and structure, out of its reach, to be used as reference. The effectiveness of the devices was assessed by collection of samples at different heights and depths in the walls and gravimetric determination of their moisture content. Conclusions are drawn on the effectiveness of the methods by comparing the moisture content before and one year after the intervention, taking into account the variation in moisture content in the reference walls.","","en","conference paper","RILEM Publications S.A.R.L.","","","","","","Campus only","","","","Heritage & Technology","","",""
"uuid:02ae9068-b58f-4dc4-85c0-b0da5990982e","http://resolver.tudelft.nl/uuid:02ae9068-b58f-4dc4-85c0-b0da5990982e","Oppervlaktebehandelingen: werkingsprincipe, afwegingen, voordelen en risico's","Lubelli, B. (TU Delft Heritage & Technology); van Hees, R.P.J. (TU Delft Heritage & Technology); Nijland, TG","","2016","","","nl","conference paper","","","","","","","","","","","Heritage & Technology","","",""
"uuid:6fa15fed-9e15-4418-b783-95f0132cfb30","http://resolver.tudelft.nl/uuid:6fa15fed-9e15-4418-b783-95f0132cfb30","Consolidation of renders and plasters","van Hees, R.P.J. (TU Delft Heritage & Technology; TNO); Veiga, Rosário (National Laboratory of Civil Engineering (LNEC)); Slížková, Z. (ITAM)","","2016","The paper addresses the consolidation of plasters and renders showing loss of cohesion, with the use of a treatment with a liquid consolidating product aiming to reach a depth of several mm up to several cm. The main aim of the paper is offering a guideline on how to choose a consolidant, suitable and compatible
for the mortar type and its condition, and how to assess the performance of a consolidation treatment.","","en","journal article","","","","","","Accepted Author Manuscript","","2017-09-01","","","Heritage & Technology","","",""
"uuid:37882c0d-dff8-4ef0-8725-031038635dda","http://resolver.tudelft.nl/uuid:37882c0d-dff8-4ef0-8725-031038635dda","Keuze van steenreparatiemortels voor historische gebouwen: geen eenvoudige zaak","van Hees, R.P.J. (TU Delft Heritage & Technology; TNO); Lubelli, B. (TU Delft Heritage & Technology; TNO)","","2016","Steenreparatiemortels worden gebruikt voor het aanvullen van een ontbrekend deel van het originele materiaal. Dat laatste kan verloren zijn gegaan door een mechanische belasting of door bijvoorbeeld aantastingsprocessen waarbij vocht, vorst en of zouten een rol spelen. Het ontbrekende deel wordt dan aangevuld met een mortel met een passende kleur en textuur. De gebruikte mortel is als het ware ‘kneedbaar’, zodat aanpassing aan de gewenste vorm eenvoudig mogelijk is. Gewoonlijk gaat het om kleinschalige ingrepen, waarbij individuele stenen, details en delen van ornamenten of beelden worden behandeld. In de kleinschaligheid, de individuele benadering en de ‘boetseerbaarheid’ liggen de voornaamste verschillen met andere ingrepen waarbij mortel wordt toegepast, zoals hervoegwerk, vervangen van pleisterwerk en dergelijke.","","nl","conference paper","","","","","","","","","","","Heritage & Technology","","",""
"uuid:c9cb1d64-daf9-439a-b88a-be46a995edab","http://resolver.tudelft.nl/uuid:c9cb1d64-daf9-439a-b88a-be46a995edab","Restorative Glass: Reversible, discreet restoration using structural glass components","Oikonomopoulou, F. (TU Delft Structural Design & Mechanics); Bristogianni, T. (TU Delft Applied Mechanics); Barou, L. (TU Delft Applied Mechanics); van Hees, R.P.J. (TU Delft Heritage & Technology); Nijsse, R. (TU Delft Applied Mechanics); Veer, F.A. (TU Delft Structural Design & Mechanics); Henk, Schellen (Eindhoven University of Technology); van Schijndel, Jos (Eindhoven University of Technology)","","2016","The application of structural glass as the principal material in restoration and conservation practices is a distinguishable, yet discreet approach. The transparency of glass allows the simultaneous perception of the monument at both its original and present condition, preserving its historical and aesthetical integrity. Concurrently, the material’s unique mechanical properties enable the structural consolidation of the monument. As a proof of concept, the restoration of Lichtenberg Castle is proposed. Solid cast glass units are suggested to complete the missing parts, in respect to the existing construction technique and aesthetics of the original masonry. Aiming for a reversible system, the glass units are interlocking, ensuring
the overall stability without necessitating permanent, adhesive connections. This results in an elegant and reversible intervention.","Glass restoration; Structural Glass; Solid glass bricks; Restoration; Preservation","en","journal article","","","","","","","Campus only","","","","Structural Design & Mechanics","","",""
"uuid:93dd8c45-02b5-4ca9-af00-20ed909826e6","http://resolver.tudelft.nl/uuid:93dd8c45-02b5-4ca9-af00-20ed909826e6","Historische mortels van de oude tijden tot de helft van de 19de eeuw","Lubelli, B. (TU Delft Heritage & Technology); Nijland, TG; van Hees, R.P.J. (TU Delft Heritage & Technology)","Nijland, T.G. (editor)","2016","","","nl","conference paper","TNO, Delft","","","","","","","","","","Heritage & Technology","","",""
"uuid:d7b3412a-dba3-4bc0-85ae-e338f5733f31","http://resolver.tudelft.nl/uuid:d7b3412a-dba3-4bc0-85ae-e338f5733f31","The volcanic foundation of Dutch architecture: Use of Rhenish tuff and trass in the Netherlands in the past two millennia","Nijland, TG (TNO); van Hees, R.P.J. (TU Delft Heritage & Technology; TNO)","","2016","Occasionally, a profound but distant connection between volcano and culture exists. This is the case between the volcanic Eifel region in Germany and historic construction in the Netherlands, with the river Rhine as physical and enabling connection. Volcanic tuff from the Eifel comprises a significant amount of the building mass in Dutch built heritage. Tuffs from the Laacher See volcano have been imported and used during Roman occupation (hence called Römer tuff). It was the dominant dimension stone when construction in stone revived from the 10th century onwards, becoming the visual mark of Romanesque architecture in the Netherlands. Römer tuff gradually disappeared from the market from the 12th century onwards. Early 15th century, Weiberner tuff from the Riedener caldera, was introduced for fine sculptures and cladding; it disappears from use in about a century. Late 19th century, this tuff is reintroduced, both for restoration and for new buildings. In this period, Ettringer tuff, also from the Riedener caldera, is introduced for the first time. Ground Römer tuff (Rhenish trass) was used as a pozzolanic addition to lime mortars, enabling the hydraulic engineering works in masonry that facilitated life and economics in the Dutch delta for centuries.","Eifel; Natural stone; The Netherlands; Trass; Tuff","en","journal article","","","","","","","","","","","Heritage & Technology","","",""
"uuid:0ab5537c-b907-4ed8-86b4-ac1903c4d2d2","http://resolver.tudelft.nl/uuid:0ab5537c-b907-4ed8-86b4-ac1903c4d2d2","Modified nanolime dispersions: Structure and colloidal stability","Borsoi, G.; Van Hees, R.P.J.; Lubelli, B.; Colla, L.; Fedele, L.; Tomasin, P.; Veiga, R.; Santos Silva, A.","","2015","","","en","conference paper","University College, London","","","","","","","","Architecture and The Built Environment","Architectural Engineering and Technology","","","",""
"uuid:c0f6e5d4-a074-45a0-8376-55252c1e3a1f","http://resolver.tudelft.nl/uuid:c0f6e5d4-a074-45a0-8376-55252c1e3a1f","Deposition of modified nanolimes within calcareous substrates","Borsoi, G.; Van Hees, R.P.J.; Lubelli, B.; Veiga, R.; Santos Silva, A.","","2015","","","en","lecture notes","","","","","","","","","Architecture and The Built Environment","Architectural Engineering +Technology","","","",""
"uuid:343eb642-780c-4d0a-a499-097945f7455b","http://resolver.tudelft.nl/uuid:343eb642-780c-4d0a-a499-097945f7455b","Nanostructured lime-base materials for the conservation and restoration of historical renders: Advantages, limitations, progresses","Borsoi, G.; Van Hees, R.P.J.; Lubelli, B.; Veiga, R.; Santos Silva, A.","","2015","","","en","lecture notes","","","","","","","","","Architecture and the Built Environment","Architectural Engineering +Technology","","","",""
"uuid:28d88e95-f798-4572-90e1-6aa975d56a30","http://resolver.tudelft.nl/uuid:28d88e95-f798-4572-90e1-6aa975d56a30","Durable past, sustainable future","Van Hees, R.P.J.; Naldini, S.; Roos, J.","","2014","The section Heritage & Architecture of the Faculty of Architecture at Delft University of Technology deals with the built environment in terms of conservation, refurbishment and re-use. Reflecting the department philosophy, this book focuses on the durability and sustainability of existing buildings (heritage in a broad sense, from historic buildings to listed monuments), considered in terms of material and building techniques, form and function, and part of the wider context of sites and cities. At the basis stands the Heritage triangle: Design – Cultural value – Technology","","en","book","TU Delft, Heritage & Architecture","","","","","","","","Architecture and The Built Environment","Architecture Engineering and Technology","","","",""
"uuid:61cd7625-cb85-40e5-aada-707f06aab4a4","http://resolver.tudelft.nl/uuid:61cd7625-cb85-40e5-aada-707f06aab4a4","Forever young or ageing naturally?","Van Hees, R.P.J.; Naldini, S.","","2014","Age and ageing can be felt as negative occurrences. For monuments however, old age is traditionally considered to be a positive quality. Without a certain age the nomination of monument hardly applies. Ageing can be seen as the work of time, which has always been valued: ageing was sometimes even artificially induced in the past. In this paper we will discuss the meaning of ageing in monumental buildings. The fact that in the case of interventions in monuments a perpetual service life is strived for, but restoration ethics clearly put limitations on what can be done, can lead to dilemmas and can make it difficult to take decisions. Cases will be discussed to derive at some criteria to base interventions upon, seeking a balance between mere preventive conservation and rejuvenating practices.","","English","conference paper","DCMat Ageing Centre","","","","","","","","Architecture and the Built Environment","","","","",""
"uuid:70496ec3-178e-4475-b822-4eb9864d8a41","http://resolver.tudelft.nl/uuid:70496ec3-178e-4475-b822-4eb9864d8a41","Study on effective modifiers for damaging salts in mortar","Granneman, S.J.C.; Ruiz-Agudo, E.; Lubelli, B.; Van Hees, R.P.J.; Rodriguez-Navarro, C.","","2014","The use of crystallization modifiers for the prevention or mitigation of salt crystallization damage has recently received a lot of research interest in the field of building conservation. However, the use of crystallization modifiers mixed in a lime-based mortar, is still a very new field of research. This paper summarizes the literature study aimed at the identification of a possible modifier for sodium sulfate, one of the most damaging salts found in porous building materials. Furthermore, the results of preliminary experiments conducted in order to test the suitability of borax as a crystallization modifier for sodium sulfate are reported and discussed.","salt crystallization damage; ageing; mortar; crystallization modifiers","en","conference paper","DCMat Ageing Centre, Delft University of Technology","","","","","","","","Architecture and The Built Environment","Architectural Engineering +Technology","","","",""
"uuid:363f94aa-21c6-40ca-933e-93271b29497b","http://resolver.tudelft.nl/uuid:363f94aa-21c6-40ca-933e-93271b29497b","Salt crystallization damage: How realistic are existing ageing tests?","Lubelli, B.; Van Hees, R.P.J.; Nijland, T.G.","","2014","Salt crystallization is a major cause of damage in porous building materials. Notwithstanding the extensive research in this field, the complexity of the problem has hindered the use of mathematical models for forecasting ageing and damage due to salt crystallization. Nowadays, the durability of materials with respect to salt crystallization is mostly determined by accelerated ageing tests, carried out in laboratory following different test procedures. An effective ageing test should simulate in laboratory, in a reliable way and within a relatively short period of time, the behaviour in practice. The question is whether existing test procedures are able to do so. This paper reports a critical overview of existing procedures and suggests directions for further research.","salt crystallization; ageing test; porous building materials; damage","en","conference paper","DCMat Ageing Center","","","","","","","","Architecture and The Built Environment","Architectural Engineering +Technology","","","",""
"uuid:ea2e818c-19e5-4d6f-93ba-13807990d070","http://resolver.tudelft.nl/uuid:ea2e818c-19e5-4d6f-93ba-13807990d070","Facade treatments of historical buildings: Limiting the risks","Van Hees, R.P.J.","","2013","The usefulness of treatment of facades of historic buildings and especially those with the status of listed monument is often discussed. Surface treatments of facades comprise a range of treatments, from water repellents to consolidants and anti-graffiti coatings. Even facade cleaning can be considered a facade treatment. Treatment of monuments and historical buildings is often subject to dispute for both ethical / aesthetical and for technical reasons. In fact, even though often advertised as reversible, surface treatments permanently alter the characteristics of the materials they are applied upon. Treatments of buildings can therefore be seen as a change of the original characteristics of the materials, thus leading to loss of information and affecting their historical value and their aesthetic appearance. During the 20th century chemistry has become increasingly important for conservation and research has been addressed towards the in-situ treatment of materials, 54 with the aim of delaying their natural decay process. In this scenery, at the beginning of the 1960’s, the first synthetic polymers (water repellents and consolidants) appeared on the market.","water-repellents, consolidants, anti-graffiti coatings, risks, drying behavior","en","conference paper","Technical Chamber of Greece","","","","","","","","Architecture","Architectural Engineering and Technology","","","",""
"uuid:2b6c6681-392a-41ac-8841-9fc5d5d92387","http://resolver.tudelft.nl/uuid:2b6c6681-392a-41ac-8841-9fc5d5d92387","Petrographic characterization of renders from the Lucchesian Villas","Bolondi, L.; Nijland, T.G.; Van Hees, R.P.J.","","2013","Around the Tuscan city of Lucca, a complex system of about 300 villa has developed between 15th and 19th centuries in a ring of territory called the Six Miles District. Nowadays, many of the buildings inside the villas enclosures are damaged and their materials – in particular renders - need to be restored. A research program was developed taking into account the complexity of the Lucchesian Villa System and economic aspects of the research: simple and clear results should be obtained avoiding expensive and long test procedures. The majority of the villas are private property, and special attention had to be reserved to landlords in order to keep them involved in the research. Four Villas from the north / northeastern part of the Six Miles District have been selected on the basis of their history, importance and available archival sources. About 80 samples of renders have been collected from ten different buildings of these villas; 19 of these have been analyzed with polarization-and-fluorescence microscopy (PFM) in order to identify materials, establish stratigraphies and mutual correlations and relationships, as part of providing a basis for selection of compatible restoration materials.","petrography, render, monuments, lucca, villas","en","conference paper","Technical Chamber of Greece","","","","","","","","Architecture","Architectural Engineering and Technology","","","",""
"uuid:2a43730e-7a24-40f0-bf71-078cbfebc310","http://resolver.tudelft.nl/uuid:2a43730e-7a24-40f0-bf71-078cbfebc310","Desalination of historic mansonry: Pre-investigation, treatment and follow-up care","Van Hees, R.P.J.; Lubelli, B.","","2013","Salt crystallization constitutes one of the most widespread decay mechanisms affecting historic buildings. Desalination is a conservation treatment of growing importance in the case of historic masonry. Salts present in porous materials cause damage through their interaction with moisture. Consequently, in certain situations the prevention of further moisture ingress can provide a solution to the problem. However, damage can also occur due to the hygroscopic uptake of moisture from the air by the salt. Hygroscopic salts can dissolve and re-crystallize due to changes in air humidity (RH) that cross their equilibrium relative humidity value. In this case, climate control may provide stable RH values and thus avoid cycles of crystallization/dissolution. However, the desired climate for preservation is not always easy to be obtained in ancient buildings. In such situations, direct intervention in the form of desalination treatments may present a better solution to the problem. This paper describes the approach from pre-investigation and treatment to follow-up care as the basis for a successful conservation of monuments suffering from salt decay. The necessity to tune the poultice properties to the substrate is underlined.","desalination; poultices; pre-investigation; follow-up care","en","conference paper","Technical Chamber of Greece","","","","","","","","Architecture","Architectural Engineering and Technology","","","",""
"uuid:c33344e5-a780-4087-9fcb-43b8cbed7bc0","http://resolver.tudelft.nl/uuid:c33344e5-a780-4087-9fcb-43b8cbed7bc0","Enhancing self-healing of lime mortars by built-in crystallization inhibitors","Granneman, S.J.C.; Lubelli, B.; Van Hees, R.P.J.","","2013","The weathering of porous materials due to the presence of salts has been known since antiquity. However, serious studies and investigations were not conducted until the 19th century. One of the fi elds of interest includes historic masonry, where salt damage can affect natural stone, brick and mortar (see Figure 1). Mortars are building materials, which are for example used in masonry, as the bonding material in between bricks or stones or as a plaster or render. Because of its pore size distribution (with both coarse as fi ne pores) and its relatively low mechanical strength, mortar is one of the building materials most affected by salt crystallization damage. As a consequence, replacement of plasters, renders and pointing mortars often constitutes a large part of total restoration costs. Salts present in masonry can originate, amongst others, from sea salt spray, rising damp, road salt, salt storage and the building materials itself.","","en","journal article","Delft Centre for Materials","","","","","","","","Architecture and The Built Environment","Architectural Engineering + Technology","","","",""
"uuid:3cc8c2d5-bd56-478a-a558-479bcce4765e","http://resolver.tudelft.nl/uuid:3cc8c2d5-bd56-478a-a558-479bcce4765e","Evaluation of Spreading and Effectiveness of Injection Products against Rising Damp in Mortar/Brick Combinations","Hacquebord, A.; Lubelli, B.; Van Hees, R.P.J.; Nijland, T.","","2013","Rising damp is one of the most recurrent and well-known hazards to existing buildings and monuments. Several types of intervention exist to tackle the problem. Among these, the creation of a damp-proof course against capillary rise by means of injection of chemical products is one of the most diffused methods, thanks to the relatively easy and cheap application. Despite positive results when applied under controlled conditions in laboratory, these interventions do not always deliver the desired result in practice. Several studies have shown varying degrees of success. Various factors, like the lack of homogeneity of the substrate and a high moisture and salt content may affect the effectiveness of treatments. Moreover, the type of substrate and the combination of materials with different pore size distribution influence the spreading and the effectiveness of chemical products. Since rising damp is a problem that is mainly manifested in masonry, that is usually composed of at least two materials, the last factor may be of great importance. The current paper reports the results of a research on the transport of chemical injection products in relatively small mortar/brick combinations. Since no easy to perform test method for small combined specimens, giving results within a short time, was available, a special test method was developed. The effect of the interface between brick and mortar on the transport of the products was studied by the application of several injection products and creams. The tested products include pore filling and water repellent products and products in water as well as in organic solvent. The obtained results show clear differences in spreading and effectiveness in the different substrates and between products in organic solvent and water based ones, as well as between creams and liquid products. The results show that water based products can easily be transported through the mortar joint, differently from what occurs with products in an organic solvent. This is the consequence of the different transport mechanisms of water based products and products in organic solvent in water filled pores.","rising damp; injection products; masonry; test methods","en","journal article","Elsevier","","","","","","","","Architecture","Architectural Engineering +Technology","","","",""
"uuid:3bf64715-5a0b-44fb-8cb7-740196c54e93","http://resolver.tudelft.nl/uuid:3bf64715-5a0b-44fb-8cb7-740196c54e93","Schadeherstel: Een zelfherstellend materiaal doet dat nu allemaal zelf","Van der Zwaag, S.; Brinkman, E.; Van Hees, R.P.J.","","2012","Er zijn momenteel heel veel ontwikkelingen gaande in het materialenveld voor de bouw: materialen met lage energy footprint, materialen van biologische oorsprong, responsieve materialen, materialen met additionele functionaliteit en al deze nieuwe materialen komen elders in deze editie aan de orde. Naast deze zichtbare en in de nog te bouwen gebouwen makkelijk herkenbare ontwikkeling van nieuwe materialen is er nog een andere ontwikkeling gaande: de ontwikkeling van zelf herstellende (self healing) materialen.","","nl","journal article","WEKA","","","","","","","","Architecture","RMIT and Media Studies","","","",""
"uuid:45b8c809-0ccd-417f-bec9-f3a4a95ccba8","http://resolver.tudelft.nl/uuid:45b8c809-0ccd-417f-bec9-f3a4a95ccba8","Delft: Nieuwe natuursteen in een oude stad","Nijland, T.G.; Quist, W.J.; Van Hees, R.P.J.","","2012","Delft is alom bekend van de Oude en de Nieuwe Kerk, beiden (deels) opgetrokken door bouwmeesters/steenhouwers van het roemruchte Brabantse geslacht Keldermans en deels in de onvermijdelijk met deze bouwmeesters verbonden witte zandige kalksteen, meestal Lede of Balegemse steen genoemd. Met name aan de Oude Kerk is echter ook nogal wat Gobertange verwerkt. Delft is ook gekend voor de grafkelder van de Oranjes en Vermeer's gezicht op de stad en toont het klassieke palet aan natuursteen gebruikelijk voor een Hollandse stad: De witte Belgische steen, behalve aan beide kerken ook aan het stadhuis en in civiele toepassingen; Römer tuf aan de Oude Kerk; Namense steen, aan de Oude Kerk maar ook aan verschillende bruggen en kademuren; wederom ook Bentheimer zandsteen aan het transept van de Oude Kerk en de toren van de Nieuwe; Obernkirchener zandsteen aan de voorgevel (en Bentheimer aan het latere bordes) en het portaal van het stadhuis; blauwe hardsteen -met groevemerken van de firma Le Prince- aan de gevels van het Gemeenlandhuis van Delfland (Oude Delft 167) en het woon-winkelpand Wijnhaven 16 (Nijland 2006, Quist 2010). Net als in de rest van Nederland vindt in de loop van de negentiende eeuw ook in Delft verbreding van het palet plaats: nieuwe soorten van verder weg doen hun intrede in de gevels. Ter gelegenheid van de vierde Vlaams-Nederlandse Natuursteendag geeft deze bijdrage een beknopt beeld van het natuursteengebruik uit de periode 1850-1965 in Delft. De bijdrage beperkt zich tot een overzicht van de voorkomens met beknopte informatie over het object; voor meer details over de steensoorten kan men elders terecht (Slinger et al. 1980, Nijland et al. 2007, 2012). De problematiek en achtergronden van de keuze van vervangende steensoorten bij restauratie wordt uitgebreid belicht in Quist (2011).","","nl","book chapter","Delftdigitalpress","","","","","","","","Architecture","RMIT and Media Studies","","","",""
"uuid:dfa3ec4e-4737-4dbf-8657-714f3d260f70","http://resolver.tudelft.nl/uuid:dfa3ec4e-4737-4dbf-8657-714f3d260f70","Confusing cracks and difficult deformations: Interpreting structural damage in masonry","De Vent, I.; Rots, J.G.; Van Hees, R.P.J.; Hobbelman, G.J.","","2012","Cracks and deformatiçns in masonry are common phenomena in historical buildings. If they are interpreted correctly, they can be an extremely valuable source çf informatiçn on the load history of the premises. Nevertheless, this interpretation is not always as obvious as one may think. In the framework of a Phd research project, an extensive literature review has resulted in an overview of SM characteristic damage patterns that can frequently be observed in traditional masonry buildings. It appears that damages that, at first glance, look very similar and straightforward to diagnose, can result from very different causes. Moreover, the research project has demonstrated that specialists from the various disciplines within building pathology are not always aware of these “look-alikes”. In order to provide an optimal intervention strategy for a building with damage, a sound diagnosis is indispensable. This can only be achieved if all relevant hypotheses are considered. This paper aims to give architects, contractors and engineers a helping hand in interpreting structural damage during visual inspections. It discusses the subsequent steps of the diagnostic process, with their essences and pitfalls. The examples provided further illustrate what cracks, deformations and tilts can tell one about the cause of damage – and what not.","structural damage; masonry; diagnosis; decision support","en","conference paper","Dolno?l?skie Wydawnictwo Edukacyjne","","","","","","","","Architecture","Architectural Engineering +Technology","","","",""
"uuid:23298450-bc31-4be1-921e-e20562ed3847","http://resolver.tudelft.nl/uuid:23298450-bc31-4be1-921e-e20562ed3847","Versneld en toch realistisch: Ontwikkeling van een snellere zoutkristallisatietest","Van Hees, R.P.J.; Lubelli, B.","","2012","Zoutkristallisatie is een van de meest voorkomende bedreigingen voor historische gebouwen. Zouten, aanwezig in poreuze materialen kunnen in interactie met vocht schade veroorzaken. Omdat vocht essentieel is voor dit schadeproces, kan onder sommige omstandigheden een ingreep, die verdere vochttoetreding tegengaat, een oplossing voor het probleem betekenen. Wanneer het materiaal al een aanzienlijke hoeveelheid zout bevat, kunnen echter zelfs wisselingen in de RV van de omgevingslucht nog kristallisatie en oplossingscycli teweeg brengen en daarmee schade veroorzaken. Maatregelen als ontzouten kunnen dan overwogen worden.","","nl","conference paper","TNO-NVMz","","","","","","","","Architecture","RMIT and Media Studies","","","",""
"uuid:cfdfc65e-fce0-46a9-8d6a-051b4775480c","http://resolver.tudelft.nl/uuid:cfdfc65e-fce0-46a9-8d6a-051b4775480c","Optrekkend vocht: Een woud van bestrijdingsproducten, -methodes en ervaringen","Hacquebord, A.; Lubelli, B.; Van Hees, R.P.J.","","2012","Metselwerk kan zwaar te lijden hebben onder verschillende degradatieprocessen. Bij veel van deze degradatieprocessen speelt vocht een grote rol. Eén van de belangrijkste en tegelijk vaak moeilijk te bestrijden vochtbronnen voor metselwerk is optrekkend vocht. Men spreekt van optrekkend vocht als water vanuit het grondpakket via de capillairen van steen en mortel tegen de zwaartekracht in omhoog gezogen wordt. Bij een geschikte combinatie van steen en mortel kan optrekkend vocht zowel in oudere als jongere gebouwen voorkomen. De kans dat het hoger optrekt als gevolg van langdurige toetreding van zouten is bij oudere gebouwen groter.","","nl","conference paper","","","","","","","","","Architecture","RMIT and Media Studies","","","",""
"uuid:754f82cd-0d31-4f33-a219-791e708e3319","http://resolver.tudelft.nl/uuid:754f82cd-0d31-4f33-a219-791e708e3319","Hoe kan effectieve ontzouting bereikt worden? Theorie en ervaringen uit de praktijk","Lubelli, B.; Van Hees, R.P.J.","","2012","Ontzouten door het gebruik van kompressen is een techniek die meer en meer gebruikt wordt in de conservering van historisch metselwerk. Niettemin, wordt ontzouten nog vaak uitgevoerd op een trial and error basis, zonder wetenschappelijke kennis van de processen die vocht- en zouttransport regelen. Om het ontzoutingsproces te optimaliseren is, binnen het Europese project Desalination, een modulair systeem van kompressen ontwikkeld. Dit is gebaseerd op het afstemmen van de porieverdeling van de kompressen op die van de ondergrond, om ontzouting op de meest efficiënte manier te bereiken. Deze aanpak is in de praktijk gebruikt bij het ontzouten van twee belangrijke monumenten: de meesterproeven in het Waag gebouw te Amsterdam en bij voorbereidende proeven aan de Porticus van het Rubenshuis te Antwerpen. In beide gevallen zijn bevredigende resultaten bereikt.","","nl","conference paper","TNO-NVMz","","","","","","","","Architecture","RMIT and Media Studies","","","",""
"uuid:31e6db06-69e0-443b-bba9-b19f4d7b2018","http://resolver.tudelft.nl/uuid:31e6db06-69e0-443b-bba9-b19f4d7b2018","Simulation of self-healing of dolomitic lime mortar","Lubelli, B.; Nijland, T.G.; Van Hees, R.P.J.","","2011","In the present research a test procedure was set up to reproduce self-healing on lime-based (both pure calcium and magnesium-calcium) mortar specimens in laboratory. After few months testing, during which the specimens were subjected to wet-dry cycles, thin sections of the specimens were prepared and observed by Polarization and Fluorescence Microscopy (PFM) and by Scanning Electron Microscope (SEM) equipped with Energy-dispersive X-ray spectroscopy (EDX). The specimens prepared with dolomitic lime showed the occurrence of self-healing: a magnesium compound is observed filling cracks and voids. These results suggest new possibilities for the development of dolomitic lime mortars with an increased self-healing capacity.","self-healing; dolomitic mortar; PFM; SEM-EDX","en","conference paper","","","","","","","","","Architecture","RMIT and Media Studies","","","",""
"uuid:cbf28278-5e71-4e59-8e3d-265be9e96395","http://resolver.tudelft.nl/uuid:cbf28278-5e71-4e59-8e3d-265be9e96395","Zout en behoud","Van Hees, R.P.J.; Lubelli, B.","","2011","Zoutkristallisatie kan leiden tot ernstige aantasting van steen en metselwerlk. Dit veelvoorkomende probleem vormt bij de zorg voor monumenten een blijvend punt van aandacht. In dit artikel wordt beschreven hoe het mechanisme van zoutkristallisatie werlct en ook op welke manieren zoutkristallisatie zich manifesteert. Het grote aantal factoren dat het schadebeeld kan beïnvloeden, maalktt het soms lastig om de oorzaak van het probleem te achterhalen. Van geval tot geval moet bekeken worden welk soort materiaaltechnisch onderzoek en welk soort onderzoek naar de herkomst van vocht en zouten noodzakelijk is.","","nl","book chapter","Gemeente Amsterdam, Bureau Monumenten & Archeologie","","","","","","","","Architecture","RMIT and Media Sciences","","","",""
"uuid:79225e5e-7c26-40b7-b7bc-185df33f8ca3","http://resolver.tudelft.nl/uuid:79225e5e-7c26-40b7-b7bc-185df33f8ca3","Fine tuning of desalination poultices: Try-outs in practice","Lubelli, B.; Van Hees, R.P.J.; De Clercq, H.","","2011","","salt; desalination; poultices; modular system; pore size","en","conference paper","University of Cyprus","","","","","","","","Architecture","RMIT and Media Studies","","","",""
"uuid:ff226ad0-ffb2-4b4c-bdb6-9881961bc7f1","http://resolver.tudelft.nl/uuid:ff226ad0-ffb2-4b4c-bdb6-9881961bc7f1","Self-healing of lime based mortars: Microscopy observations on case studies","Lubelli, B.; Nijland, T.G.; Van Hees, R.P.J.","","2011","Lime mortars have, up to a certain extent, a self-healing capacity which may contribute to their durability. Self-healing in lime mortars consists of a process of dissolution, transport and re-precipitation of calcium compounds to heal cracks and fissures. The spontaneous occurrence of self-healing in lime-based mortars is a well known phenomenon; to date, however, little research has been done on its occurrence in the practice. This study aims at gaining a better understanding of the self-healing mechanism in lime-based mortars through the investigation of case studies where self-healing has been observed. On the basis of the results obtained the relevance of the various controlling factors, the way in which they potentially interact, and how they affect the occurrence of self-healing is evaluated. Lime-based mortar samples collected from several case studies were studied. Thin sections were prepared and studied by means of Polarization & Fluorescence Microscopy (PFM). The influence of selected parameters (moisture content, degree of carbonation, binder-sand ratio, binder type, etc.) on the nature (calcium carbonate or calcium hydroxide) and crystal habits of the precipitated products has been investigated. The results obtained indicate that some recurrent patterns exist in the nature and the crystal habits of the re-precipitated products depending, among other factors, on the moisture content and on the degree of carbonation of the mortar.","Self-healing; lime mortars; calcite; portlandite; microscopy","en","journal article","","","","","","","","","","","","","",""
"uuid:a9f48619-9146-4986-9ba2-b1af95211399","http://resolver.tudelft.nl/uuid:a9f48619-9146-4986-9ba2-b1af95211399","Desalination of historic masonry: From pre-investigation to after-care","Van Hees, R.P.J.; Lubelli, B.","","2010","Salt crystallization constitutes one of the most widespread decay mechanisms affecting historic buildings. Desalination is a conservation treatment of growing importance in the case of historic masonry. This paper describes the approach from pre-investigation and treatment to follow-up care as the basis for a successful preventive conservation of monuments suffering from salt decay.","","en","journal article","","","","","","","","","Architecture","Architectural Engineering and Technology","","","",""
"uuid:9c55ee74-90f2-464a-96f5-668c223042d4","http://resolver.tudelft.nl/uuid:9c55ee74-90f2-464a-96f5-668c223042d4","Effect of climate change on built heritage: Preface","Van Hees, R.P.J.","","2010","","","en","lecture notes","WTA","","","","","","","","Architecture","Architectural Engineering +Technology","","","",""
"uuid:7dbf1f28-ec63-4e4a-a6f0-9cbf7b45bfde","http://resolver.tudelft.nl/uuid:7dbf1f28-ec63-4e4a-a6f0-9cbf7b45bfde","Assessment of the state of conservation of a Middle Neolithic flint mine in Maastricht limestone","Van Hees, R.P.J.; Nijland, T.G.","","2009","Upper Cretaceous Maastricht limestone (""mergel"") outcrops in the provinces of Dutch and Belgian Limburg. The Upper Cretaceous in the Netherlands consists of the geological Maastricht Formation and the upper part of the Gulpen Formation. Limestones from the Maastricht Formation represent one of the few native Dutch natural stones used for building and construction. Locally, limestone from both formations contains considerable amounts of flint. This flint has been mined in Neolithic times, both from the Lanaye limestone in the Gulpen Formation and the Emael Limestone in the Maastricht Formation. Around the village of Valkenburg aan de Geul, flint was mined from the latter. In the current study, the state of conservation of a Middle Neolithic flint mine situated at the Plenkertweg in Valkenburg aan de Geul is assessed, 8 years after the site was discovered and exposed.","Maastricht limestone; mergel; flint mining; ancient mine; Neolithic; conservation; Valkenburg","en","journal article","","","","","","","","","Architecture","RMIT en Media Studies","","","",""
"uuid:0bd24f6c-6700-4218-943e-ff852d173f03","http://resolver.tudelft.nl/uuid:0bd24f6c-6700-4218-943e-ff852d173f03","Salt decay of Morley limestone","Nijland, T.G.; Van Hees, R.P.J.","","2009","Salt weathering is one of the main causes of decay of natural stone, and by consequence a major problem to the conservation of cultural heritage. In the present case, the performance of Morley limestone from the Département Meuse, France, as a replacement stone under saltloaded conditions is evaluated. Morley limestone was used in the Netherlands as a replacement stone for sandy Eocene Belgian limestones (Gobertange, Lede).","Morley limestone; salt weathering; Pieterskerk; Leiden","en","journal article","","","","","","","","","Architecture","","","","",""
"uuid:57211f90-c11a-4059-802f-12cf4eef6697","http://resolver.tudelft.nl/uuid:57211f90-c11a-4059-802f-12cf4eef6697","Salt transport in plaster/substrate layers","Petkovic, J.; Huinink, H.P.; Pel, L.; Kopinga, K.; Van Hees, R.P.J.","","2007","","","en","journal article","Springer","","","","","","","","Architecture","","","","",""
"uuid:40fc768c-c68a-4a98-b091-9c71c7b80380","http://resolver.tudelft.nl/uuid:40fc768c-c68a-4a98-b091-9c71c7b80380","Effect of NaCl on the hydric and hygric dilation behaviour of lime-cement mortar","Lubelli, B.; Van Hees, R.P.J.; Huinink, H.P.","","2006","","","en","journal article","","","","","","","","","Architecture","","","","",""
"uuid:0d703130-494d-4a9a-8f78-be8f7bfdf279","http://resolver.tudelft.nl/uuid:0d703130-494d-4a9a-8f78-be8f7bfdf279","De restauratie voorbij","Van Hees, R.P.J.","","2004","","Intreerede","nl","public lecture","","","","","","","","","","","","","",""
"uuid:3db299fb-5ff5-4beb-8182-fa43c49e0784","http://resolver.tudelft.nl/uuid:3db299fb-5ff5-4beb-8182-fa43c49e0784","Lithofacies and Petrophysical Properties of Portland Base Bed and Portland Whit Bed Limestone as Related to Durability","Dubelaar, C.W.; Engering, S.; Van Hees, R.P.J.; Koch, R.; Lorenz, H.G.","","2003","This study focuses on the differences in lithofacies and petrophysical properties of Base Bed and Whit Bed Portland limestone and the presumed relationships between these characteristics and the durability of this building stone. As Portland limestone probably will be used as a stone for several restoration projects in the Netherlands in the near future, it is of great importance to know the weathering behaviour, especially its resistance against freeze/thaw decay. Samples of Portland limestone were analyzed by means of thin section microscopy, X-Ray fluorescence spectroscopy, and measurements of petrophysical properties such as watersaturation, porosity, permeability and specific surface area. Distribution of pore throat diameters were analyzed by mercury porosimetry. Results of a freeze/thaw test performed on Whit Bed limestone were also taken in account. The Whit Bed consists of a medium grained, fine to coarse bioclastic oolific limestone (oobiosparite; oolitic grainstone). Generally the fabric is grain supported showing a large amount of open inter-particle pores. High effective porosity combined with high permeability (1000 - 1400 milliDarcy), predominantly reflect the open interparticle porosity. The Base Bed is also a coarse bioclastic oolitic grainstone, but the oolitic fabric shows a tighter, matrix-rich compacted texture. Samples from the Base Bed show differences in primary matrix contents compared to the Whit Bed and differences in diagenesis, resulting in different physical properties. For example, a lower effective porosity (15.11 - 15.99 vol.%) and a lower permeability (35.0 - 80.1 milliDarcy). It is concluded that a thorough study of lithofacies (especially microfacies) and analysis of microporosity reveal basic data for selecting the most durable type of limestone. In this particular case, using only samples from one quarry, the Whit Bed samples are thought to be the most durable ones","","en","journal article","Delft University of Technology","","","","","","","","Architecture","","","","",""
"uuid:c00a6671-d5e0-41bb-8ef7-ff433917022b","http://resolver.tudelft.nl/uuid:c00a6671-d5e0-41bb-8ef7-ff433917022b","Decay of Rhenish Tuffs in Dutch Monuments. Part 2: Laboratory Experiments as a Basis for the Choice of Restoration Stone","Van Hees, R.P.J.; Brendle, S.; Nijland, T.G.; De Haas, G.J.L.M.; Tolboom, H.J.","","2003","Rhenish tuffs (Eifel, Germany), have been used as building material in the Netherlands since Roman times. They were the most important natural building stone in the Netherlands in early medieval times. In addition, tuff was used as raw material for production of trass, that served as a pozzolanic addition for mortars. Rhenish tuffs, notably Römer, Weiberner and Ettringer, show remarkable differences in decay. Ettringer tuff applied during late 19th -early 20th century restorations often shows severe deterioration, whereas, for example, most 14th century Römer in rampant arches on top of St. John's cathedral, 's Hertogenbosch, resisted weathering reasonably well, as do sculptures out of the more fine-grained Weiberner tuff on top of these. In order to obtain a better understanding of the processes underlying the decay of these tuffs and the compositional factors controlling them, a research project was started that includes both on site investigations of major monumental buildings in the Netherlands (partly) built with tuff and laboratory research. Fresh quarry samples of Römer, Ettringer and Weiberner tuff were used for selected physical characterization and testing, including a.o. hydric dilation, drying behaviour and frost resistance. One type of Römer showed a remarkably high resistance against frost. The results of the laboratory experiments on quarry samples are reported. The experiments provide a sound basis for the choice of restoration stone","","en","journal article","Delft University of Technology","","","","","","","","Architecture","","","","",""
"uuid:01d05baa-9a1b-4c1c-8abc-911b541d7caa","http://resolver.tudelft.nl/uuid:01d05baa-9a1b-4c1c-8abc-911b541d7caa","Black Weathering of Bentheim and Obernkirchen Sandstone","Nijland, T.G.; Dubelaar, C.W.; Van Hees, R.P.J.; Linden, T.J.M.","","2003","Black weathering of sandstone in monuments is widespread. Some objects owe their name to it, like the Porta Nigra in Trier (Germany). Other than the black gypsum crusts common on limestone, the black weathering layer on sandstone is rather thin and well adherent. Formation of such layers on Bentheim and Obernkirchen sandstone, both widely used in the Netherlands, has been investigated by microscopy and whole rock chemistry. Samples were obtained from several monuments in the Netherlands, amongst them the Old and New Church (Delft), St. John's cathedral ('s Hertogenbosch) and St. Plechelmus' basilica (Oldenzaal). Microscopically, the layers are composed of algae and fungi, gypsum, airborne particles such as fly ash, and iron (hydr)oxides, present on the surface and in directly adjacent pores. Gypsum is present in all samples, algae are not, but typically occur in the most blackish layers. Black layers show significant increases in loss on ignition (LOI), total and organic carbon, total sulfur and iron, as well as Pb, Cu, Zn and Sn. Formation of thin black layers is evidently not due to a single process, but involves formation of gypsum, deposition of airborne material, microbiotic activity and dissolution and redeposition of Fe-(hydr)oxides.","","en","journal article","","","","","","","","","Architecture","","","","",""