The performance of interface transition zone of recycled composite micro-powder concrete
In order to study the influence mechanism of recycled composite micro-powder compound mixing ratio on the performance of the interface transition zone of concrete,the influence of different compound mixing ratios on the splitting tensile strength and microhardness of concrete was analyzed by combining macro and micro experiments,and the correlation between mechanical properties and micro-structure was explored using the grey correlation method.The results show that the improvement effect of recycled brick powder on concrete is better than that of recycled concrete powder,and the micro-structure of the interface transition zone of concrete can be improved by adding reasonable recycled composite micro-powder.The microhardness relationship of each phase of recycled composite micro-powder concrete is as follows:the aggregate phase>the mortar phase>the interface transition zone phase,with the interface transition zone thickness gradually decreasing as the maintenance ages in-crease.The thickness of the interface transition zone has a significant relationship with the splitting ten-sile strength,showing a linear negative correlation.The established model has a high degree of fit.The study suggests that the thickness of the interface transition zone can accurately characterize the macro-scopic performance change rule of recycled composite micro-powder concrete.When the ratio of recy-cled concrete powder to recycled brick powder is 2:8,high-performance C30 concrete can be pre-pared,which has good promotion and application value.