Effect and mechanism of action of glass waste powder as an additional binder on the properties of recycled concrete

As an additional binder, glass powder (GP) is a good replacement for cement in the production of recycled aggregate concrete (RAC), which is beneficial for recycling solid waste resources and reducing environmental pollution. The effects of 10 %, 20 % and 30 % by weight of GP which partially replaces cement on the compressive strength, splitting strength, elastic modulus, drying shrinkage, and creep of RAC were studied; the internal microstructure was also analyzed by MIP and nanoindentation techniques. The results show that GP reduces the compressive strength, splitting strength and elastic modulus of RAC at the early stage, while at the later stage, the compressive strength and elastic modulus for RAC containing 10 % and 20 % GP are higher than those of the control group. In addition, a GP additive reduces the drying shrinkage and creep of RAC, and the sample containing 10 % GP shows the best effect. Due to the pozzolanic effect and the effect of microaggregate filling of GP, the microstructure of the RAC matrix and the interfacial transition zone (ITZ) improves.