Assessment of self-healing behavior of polypropylene fiber-reinforced cement mortar with crystalline admixture: the effects of crack widths, cracking ages, and external conditions

Crystalline admixture (CA) is an effective self-healing agent for mortar. However, the effects of crack parameters (i.e. crack width and cracking age) and the service environment on the self-healing behavior of CA-containing mortar are not well understood. Herein, the self-healing behavior of mortar containing a self-developed CA was assessed...

Archaeological Adhesives

An adhesive is any substance that bonds different materials together. This broad definition includes materials used in everything from hafted stone tools to monumental architecture. In addition, the combination of bonding, plasticity, and insolubility meant that some adhesives were exploited for waterproofing and sealing of materials, as self...

Analysis of microcracking formation during basic and drying creep in cementitious materials

The safety of double wall Concrete Containment Buildings (CCBs) in the French nuclear fleet primarily depends on the level of prestress applied to concrete. The delayed strains in concrete induced by creep and shrinkage cause a loss of prestress in the inner wall that may increase the risk of potential leaks in accidental conditions. The creep...

Investigation of porosity and carbonation depth in alkali-activated GGBS mortar

The effect of type of activator on porosity and CO2 penetration of the alkali activated ground granulated blast furnace slag (GGBS) mortar is an important behavior which is required for designing a durable concrete mixture. This research article investigates the influence of three types of activators consisting of NaOH, Na2.nSiO2 and K2.nSiO2 on...

Behavior of reinforcing steel and reinforced concrete undergoing stray current

Currents flowing along paths not being elements of a purpose-built electric circuit, are called stray currents. Various types of reinforced concrete structures (such as viaducts, bridges and tunnels) in the neighborhoods of railways may be subjected to stray current leaking from the rails. In these cases the concrete pore solution acts as an...

Modelling the mechanical response of adobe components under uniaxial loadings

This paper presents a constitutive relationship to describe the uniaxial response in statics of brick and mortar samples of Adobe. This defines a traditional masonry whose components are made of soil mixture reinforced with fibres. Only recently Adobe has started attracting scientific attention, primarily as a consequence of the dramatic...

Study on effective modifiers for damaging salts in mortar

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...

Bacteria-based self-healing concrete to increase durability of structures

Bio-healing for micro-crack treatment in cementitious materials: Toward a quantitative assessment of bacterial efficiency

Bio-healing is a promising approach to enhancing natural self-healing and thus completely heal large micro-cracks (> 200 ?m) in cementitious materials. The aim of this research is to better understand bio-healing of cementitious materials in order to accelerate the healing kinetics and maximize sealing efficiency of large micro-cracks. The bio...

Meso Mechanical Analysis of AC Mixture Response

Ongoing research into performance modeling of Asphalt Concrete (AC) mixtures using meso mechanics approaches is being undertaken at Delft University of Technology (TUD). The approach has already been successfully employed for evaluating the long term performance of porous asphalt concrete. The work presented in this paper extends the use for...

The Effect of Ageing on the Fatigue and Healing Properties of Bituminous Mortars

Nowadays, reclaimed asphalt aggregate is often used in new asphalt mixtures. In Flanders, up to 50 % of the binder content is allowed to be originating from reclaimed asphalt. However, the effect of this aged binder on the fatigue and healing properties of the asphalt mixture is questioned. A procedure for the ageing of asphalt mixtures, mortars...

Response Modelling of Bitumen, Bituminous Mastic and Mortar

This research focuses on testing and modelling the viscoelastic response of bituminous binders. The main goal is to find an appropriate response model for bituminous binders. The desired model should allow implementation into numerical environments such as ABAQUS. On the basis of such numerical environment, Delft University of Technology (TU) is...

The influence of materials characteristics and workmanship on rain penetration in historic fired clay brick masonry

Moisture is a major source of damage in historic solid masonry. Therefore, control of moisture movement in masonry is instrumental to the durability of masonry buildings. From research and practical experience it is known that many factors may play a role regarding permeability problems in masonry. This paper is focused on materials aspects...

Dry and hydraulic extensile fracturing of porous impermeable materials

Extensile hydraulic fracturing of mortar is investigated and compared to extensile dry fracturing of sandstone. The extensile fracture experiments have been performed in a Hookean cell in deformation control. The cell allows for axial loading and radial fluid pressure loading of cylindrical specimens. Variables in the experiments are the load...