Effects of Glass Powder as a Supplementary Cementitious Material on the Performance of High Strength Mortars

Concrete, is the most widely used engineering material in construction. Since around 11 billion tons of concrete is used each year all over the world, considerable amount of cement is required for its production. This results in high production of carbon dioxide which is one of the main reasons of global warming. Therefore, in the last few years, there is a growing interest in using waste pozzolanic admixtures as a supplementary cementitious material. Using these kind of admixtures as a part of cement replacement reduces the air pollution, cost and also enhances some properties of mortars and concretes. Among the other waste natural pozzolans, glass powder becomes important due to its high content of silica, availability and cost. These motivate lots of researchers to evaluate the effects of glass powder as a cement replacement material. In this study, effects of three different types (colors) of glass powders with different quantities used as cement replacement on the workability and mechanical properties of high strength mortars were evaluated. For this purpose, the flow table test for workability, flexural and compressive strength tests, modulus of elasticity measurement, rapid chloride test for permeability were performed to determine the effects of water binder ratio on high strength mortars performance. Moreover, the effect of curing temperature on the performance of high strength mortars modified with glass powders was also investigated. Finally, comparison is done between the results of control, silica fume and glass powder specimens. It is important to note that glass powder addition as a pozzolanic material has a considerable influence on compressive strength and permeability at low water binder ratio specimens under high curing temperature. Keywords: glass powder, curing temperature, water-binder ratio, workability, compressive and flexural strength, modulus of elasticity, permeability