Experimental Study on Properties of Hydraulic Mortars with Mixed in Crystallisation Inhibitors

Experimental Study on Properties of Hydraulic Mortars with Mixed in Crystallisation Inhibitors

Kamat, Ameya (TU Delft Heritage & Architecture)
Lubelli, B. (TU Delft Heritage & Architecture)
Schlangen, E. (TU Delft Materials and Environment)

Bosiljkov, V.Bokan (editor)

2023

Sodium chloride (NaCl) is one of the most commonly occurring weathering agents, responsible for a progressive damage in mortar. Current solutions to mitigate salt damage in mortar, such as the use of mixed-in water repellent additives, have often exhibited low compatibility with the existing building fabric. In the last years, research has shown promising results in mitigating salt decay by making use of crystallisation inhibitors. Sodium ferrocyanide is one of the inhibitors that has proven to be particularly effective to reduce damage due to sodium chloride crystallisation. In this research the possibility of developing hydraulic mortars with mixed-in inhibitor (sodium ferrocyanide) for an improved resistance to sodium chloride crystallisation damage is investigated. As a first step, the interaction between the inhibitor and the hydraulic binder: natural hydraulic lime (NHL), was studied; the results are presented in this paper. Various concentrations of sodium ferrocyanide were tested (0%, 0.1% and 1% by binder weight). The effect of the inhibitor on several physical (hydration, water absorption, pore size distribution) and mechanical (compressive and flexural strength) properties was experimentally assessed, using several complementary methods and techniques. The results show that the addition of the sodium ferrocyanide does not affect the fresh and hardened properties of mortar. These results are promising and open new possibilities for the application of inhibitors to improve the durability of hydraulic mortars.

conservation
crystallisation inhibitor
Natural hydraulic lime
Repair mortars
salt damage
sodium chloride
sodium ferrocyanide

http://resolver.tudelft.nl/uuid:da1b83f6-d797-49ee-8284-314749de9e28

https://doi.org/10.1007/978-3-031-31472-8_26

Springer

2023-12-08

HMC 2022: Conservation and Restoration of Historic Mortars and Masonry Structures

RILEM Bookseries, 2211-0844, 42

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.

Institutional Repository

book chapter

© 2023 Ameya Kamat, B. Lubelli, E. Schlangen