Properties of mortar and concrete

Effects on the plastic and hardened properties of mortar and concrete... 

Murata, K. et al. (1994) The effect of characteristics of silica fume on physical properties of mortar and concrete (in Japanese). Simento Konkurito Ronbunshu 48,364-369 [ref CA 123/151172]. 

The changes in cement characteristics due to prehydration affect the properties of mortars and concretes. Especially when admixtures and complex... 

Synthetic (polymer) fibres are increasingly being used for the reinforcement of cementitious materials. Some fibres, such as polypropylene, are used very extensively, and many fibres are available that have been formulated and produced specifical ly for rei nforcement of mortars and concretes. The properties of synthetic fibres vary widely with respect to strength and modulus of elasticity, as shown for some common fibres in Table 10.1. 

Abdelrazig, B. E. I., Sharp, J. H. El-Jazairi, B. (1989). Microstructure and mechanical properties of mortars made from magnesia-phosphate cement. Cement Concrete Research, 19, 247-58. 

J. Jasiczak and K. Zielinski, Effect of protein additive on properties of mortar, Int. J. Cement Compos. Lightweight Concrete, 28, 451 457 (2006). 

Although the mix design of latex-modified mortar and concrete is done in much the same way as that of ordinary mortar and concrete, properties such as workability, strength, extendibihty, adhesion, watertightness and chemical resistance are controlled by the polymer-cement ratio rather... 

The presence of the cement hydrate/polymer comatrix in LMM and LMC confers superior properties, such as high tensile and flexural strengths, excellent adhesion, high waterproofhess, high abrasion resistance and good chemical resistance, when compared to ordinary cement mortar and concrete. The degree of these improvements however depends on polymer type, polymer-cement ratio, water-cement ratio, air content and curing conditions. Some of the properties affected by these factors are discussed below [87, 88, 93-95]. 

S.Furukawa, A.Kojima and T.Asada, Mechanical Properties of Light-Weight Mortar with Powder of Scrap FRP (in Japan) JCA Proceedings of Cement and Concrete, V. 47, Oct. 1993, pp. 244—247... 

Ohama, Y. (1987), Principle of Latex Modification and Some Typical Properties of Latex-Modified Mortars and Concretes, ACI Materials Jounal, November-December, pp. 511-518. 

Jambor has, apparently, been able to relate the changes observed in the physical and mechanical properties of the specimens to changes in the bound SO3 content. These data, however, were not given in the paper. The data presented relate bound SO3 content to sulfate concentration, C3A content, and time of testing. It is these data upon which the damage function was based. As Jambor points out, the damage function is limited in that it does not take into account temperature effects, influence of the cement content in the mortars and concrete, total porosity of the composite material, as well as the Influence of the cross-section size of the structure. It does, however, serve to give a first approximation. 

Over the centuries, other pozzolanic substances were blended with slaked lime to produce what are now called synthetic (or artificial) hydraulic limes. Both naturally occurring pozzolans (such as trass, found in Germany), and synthetic pozzolans (such as ground blast furnace slag) have been, and still are used. It was also found that some impure limestones, containing silica and alumina, produced slaked limes with a range of hydraulic properties. Such natural hydraulic limes were widely used in construction and building for mortar and concrete. 

Although polymers and monomers in any form such as latexes, water-soluble polymers, liquid resins, and monomers are used in cement composites such as mortar and concrete, it is very important that both cement hydration and polymer phase formation (coalescence of polymer particles and the polymerization of monomers) proceed well to yidd a monolithic matrix phase widi a network structure in which the hydrated cement phase and polymer phase interpenetrate. In the polymer-modified mortar and concrete structures, aggregates are bound by such a co-matrbc phase, resulting in the superior properties of polymer-modified mortar and conoete compared to conventional. 

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