骨料粒径对混凝土界面过渡区弹性模量与黏结强度影响预测

Influence of aggregate size effect on elastic modulus and strength of interfacial transition zone of concrete

由于弹性模量和强度是混凝土力学性能重要指标,而界面过渡区又是混凝土材料组成中的重要一相,因此对界面过渡区的弹性模量和黏结强度的研究十分必要。基于随机骨料模型,根据混凝土试件的真实配合比,计算出各骨料粒径区间的面积含量,对骨料颗粒进行随机投放,分别建立了骨料最大粒径20、40、60、80 mm的凸多边形随机骨料细观模型,以砂浆和混凝土的弹性模量和抗压强度实测值为依据,采用反演法确定界面过渡区的力学参数。数值分析的结果表明:骨料粒径对界面过渡区黏结强度有很大影响,随着骨料粒径的增大,其黏结强度逐渐减小;界面弹性模量随着骨料粒径增加变化很小。

Because of elastic modulus and strength are important index of concrete,interfacial transition zone is a part of it,so it is necessary to study on elastic modulus and strength of interfacial transition zone.The mix proportion of concrete is calculated for aggregate content according Monte Carlo random sampling principle.The maximum size of coarse aggregate 20,40,60 and 80 mm random convex polyhedral aggregate model were respectively established by random aggregate packing.The elastic modulus and strength of interfacial transition zone was regarded as a parameter,with the test measurement of motor and concrete.The results showed that the maximum size of coarse aggregate has significant effect on strength of interfacial transition zone,and strength of interfacial transition zone will decrease by maximum size of coarse aggregate increasing.The maximum size of coarse aggregate has no significant effect on elastic modulus of interfacial transition zone.