高分子固化剂对水泥土强度的影响研究

Studies on the effect of the polymeric consolidator on the strength of cement soils

为研究高分子固化剂对水泥土强度的影响,对不同高分子固化剂掺量和土质条件下的水泥土进行室内无侧限抗压强度试验,从宏观上分析高分子固化剂对水泥土强度的影响规律;结合X射线衍射测试和扫描电镜测试,从微观结构上揭示高分子固化剂作用机理,分析高分子固化剂掺量和土质对水泥土强度的影响。宏观分析结果表明:在粉质黏土中,高分子水泥土的抗压强度高于普通水泥土,在粉土中两者强度相近,且两种土质中高分子固化剂掺量变化对水泥土强度影响较小;高分子水泥土在粉质黏土中的韧性表现优于普通水泥土;高分子水泥土在粉质黏土中的破坏应变大于普通水泥土;高分子水泥土在两种土质中的强度不随高分子固化剂掺量的增加而增加。微观测试结果表明:高分子水泥土在粉土中生成较多低硬度矿物成分;高分子水泥土内存在的高分子固化膜,对土颗粒进行包裹、填充与连接,增强了土颗粒之间的黏结。该结果可为地基处理材料相关研究提供一定的参考。

In order to study the effect of the polymeric consolidator on the strength of cement soils, we carried out unconfined compressive strength tests of cement soils with different polymeric consolidator contents and soil properties in the laboratory, and explored the influence law of the polymer consolidator on the strength of cement soils macroscopically. Combined with X-ray diffraction test and scanning electron microscope test, the mechanism of the polymeric consolidator′s effect on the strength of cement soils was revealed from microstructure. The tests show that the compressive strength of polymer cement soils is higher than that of ordinary cement soils in silty clay while similar with that of ordinary cement soils in silty soils, and the dosages of the polymeric consolidator in the two kinds of soils have insignificant effects on the strength of cement soils. The toughness of polymer cement soils is superior to that of ordinary cement soils while the failure strain of polymer cement soil is higher than that of ordinary cement soils in silty clay. The strength of polymer cement soil does not increase with the increase of the polymeric consolidator. The microscopic test results show that the polymer cement soils produce a large amount of low-hardness mineral components in the silty soils;the polymer cured film in the polymer cement soils forms a stable structure through wrapping, filling and connecting soil particles, enhancing the bond strength between soil particles. The results can provide some reference for the research related to foundation treatment materials.