关键词: 碱式硫酸镁水泥混凝土;干湿循环;抗硫酸盐腐蚀

Abstract: The sulfate corrosion resistance of basic magnesium sulfate cement(BMSC)concrete was investigated by dry-wet cycles.The influence of damage degree on the sulfate resistance of concrete was analyzed via the rate of mass loss and relative dynamic elastic modulus.The sulfate corrosion resistance of that without mineral admixtures(BMSC),with 30％fly ash(BMSC-F)basic magnesium sulfate cement and ordinary Portland cement(POC)concrete was studied.The result indicates that the quality of concrete increases slowly at the early period of the dry-wet cycles and the quality of the concrete damages obviously later.When under dry-wet cycling conditions,the relative dynamic module of elasticity of the BMSC concrete Erd exhibits a increasing stage followed by a slow decreasing stage,then a linear increasing stage,and finally the failure stage.The relative dynamic module of elasticity of the POC concrete Erd increases first and then decreases with the times of dry-wet cycles increasing.And under the same conditions,the sulfate corrosion resistance of BMSC concrete is better than that of POC concrete.And adding fly ash can improve the sulfate corrosion resistance of BMSC concrete.

Key words: basic magnesium sulfate cement concrete;dry-wet cycles;sulfate corrosion resistance