Study of high-strength mortar prepared by low heat expansive cement
Low heat expansion cement(LHEC)is a type of low-carbon cement with low heat of hydration and micro expan-sion properties.The high-strength mortars were prepared with LHEC and Portland-slag cement(PS),and three water curing condi-tions were set at 20,45,70 ℃.The strength and expansion of the mortars at different curing temperatures were compared.Based on XRD and SEM analysis,the related mechanism was discussed.The results show that the high-strength mortars prepared by LHEC have higher flexural strength,flexural-to-compressive ratio and expansion than that prepared by PS.The flexural strength,compressive strength and expansion are highest at 45 ℃for the former,and highest at 70 ℃ for the latter.The expansion of the latter is very small and doesn't changed obviously with temperature.High-strength mortars prepared by LHEC introduces more et-tringite(AFt),and the curing temperature promotes the hydration of slag and the formation of AFt,however causes the transforma-tion of AFt to the calcium sulphoaluminate hydrates(AFm)when it is too high.
万方数据
维普
