配合比参数对混凝土硫酸盐冻融破坏的影响

Effects of Mix Ratio Parameters on Freeze-thaw Damage of Concrete Sulfate

以用于渠道衬砌的混凝土为例,利用二次通用旋转组合设计优化渠道衬砌用混凝土配合比参数,选取粉煤灰、矿渣、粗骨料体积率、水灰比4个因素,以渠道衬砌用混凝土硫酸盐冻融300次后的相对动弹性模量为指标,建立回归模型,通过对试验结果的方差分析及对所建立模型的优化得到混凝土的最优配合比。结果表明,混凝土抗硫酸盐冻融最优参数为粉煤灰掺量110kg/m^3,矿渣掺量70kg/m^3,粗骨料体积率为0.335,水灰比0.4,在该最优条件下混凝土相对动弹性模量为90%,二次通用旋转组合设计优化所得混凝土配合比具有良好的抗冻耐久性。

Taking the concrete used for canal lining as the research object,the mix ratio parameters of concrete were optimized by the quadratic universal rotary combination design.Four factors including fly ash,slag,coarse aggregate volume ratio and water-cement ratio were selected,and the relative dynamic elastic modulus of concrete after 300 times of sulfate freeze-thaw was used as the index to establish the regression model.The optimal mix ratio of concrete was obtained by variance analysis of test results and optimization of the established model.The results show that the optimal parameters of concrete against sulfate freeze-thaw are as follows:fly ash content of 110 kg/m^3,slag content of 70 kg/m^3,coarse aggregate volume ratio of 0.335,water-cement ratio of 0.4.Under this optimal condition,the relative dynamic elastic modulus of concrete is 90%.The concrete mixture ratio obtained by the optimization of the quadratic universal rotary combination design has good frost resistance and durability.