Impact of sand-to-binder ratio on the strength and shrinkage performance of geopolymer mortar
To study the effect of sand-to-binder ratio on the strength and shrinkage of geopolymer mortar,tests were conducted on various properties including flexural strength,compressive strength,flexural-to-compressive strength ratio,drying shrinkage,and porosity.Results showed that both flexural and compres-sive strength initially increased and then decreased with the sand-to-binder ratio,peaking at ratios of 0.4 and 0.2 respectively.Additionally,the flexural-to-compressive strength ratio increased with the sand-to-binder ratio,while drying shrinkage initially decreased and then increased,reaching a minimum at a ratio of 0.3.An increase in the sand-to-binder ratio led to higher porosity and larger pore sizes,reducing mortar density significantly.These findings offer valuable insights for optimizing geopolymer mortar mixtures and future research.