有机质浸染砂-水泥土微观结构的定量分析

Quantitative Approach on Micro-Structure of Cement-Stabilized Organic Matter-Disseminated Sand

为了研究有机质存在对砂-水泥土力学特性的影响,本文首先对不同养护龄期(7 d、14 d,、21 d、28 d)下的有机质浸染砂-水泥土和标准砂-水泥土进行了SEM试验,然后采用Image Pro-Plus软件对水泥土的微观结构图像进行定量分析.结果表明:1)随着养护龄期的增加,有机质浸染砂-水泥土微观结构的孔隙逐渐减少,胶结程度增强,而28 d的有机质浸染砂-水泥土的胶结程度比7 d标准砂-水泥土的胶结程度差:2)有机质浸染砂-水泥土结构单元体的丰度值主要集中在0.7左右,其结构单元体的丰度值占比较少,而在7 d标准砂-水泥土中水泥的水化反应较完全,其微观结构趋于稳定;3)由有机质浸染砂-水泥土和标准砂-水泥土的结构单元体和孔隙的定向角分布图可知,水泥土没有明显的定向性.

In our report,in order to study the influence of the presence of organic matter on the mechanic characteristics of the sand-cement-soil,SEM tests on the organic matter disseminated sand-cement-soil and standard sand-cement-soil under different curing ages(7 d,14 d,21 d,28 d)were performed,and then,Image Pro-Plus software was used to quantitatively analyze the microstructure image of cement-stabilized soil.The results showed that:1)with the increase of the curing time,the porosity of micro-structure of the organic matter disseminated sand-cement-soil decrease,the degree of cementation increase,however,the degree of cementation of the organic matter disseminated sand-cement-soil(28 d)is worse than that of the organic matter disseminated sand-cement-soil(7 d);2)the abundance values of the structural units of the organic matter disseminated sand-cement-soil are about 0.7 mainly,whose ratio are small,however,the hydration reaction of the cement in the 7 d standard sand-cement-soil is relatively complete,and the microstructure tends to be stable;3)the distribution diagram of the directional angles of the unit cells and pores of the organic matter disseminated sand-cement-soil and standard sand-cement-soil show that the cement soil has no obvious orientation.