长江阶地粉质黏土相似材料配比试验研究

为确定长江阶地粉质黏土相似材料配比方案,本文研究原材料间配比关系。基于三因素三水平正交试验设计方法,以滑石粉、膨润土、石英砂和水为原料,配置基坑模型试验粉质黏土相似材料,通过剪切试验获取九组配比方案的黏聚力和内摩擦角两个物理力学指标,采用极差法和方差法分析各因素的敏感性与显著性,研究滑石粉、膨润土、石英砂以及水含量对黏聚力和内摩擦角的影响规律。结果表明:极差法与方差法分析结果具有一致性,两种方法能合理判断各因素对考察指标的敏感性与显著性;膨润土掺量虽少,但对粉质黏土的黏聚力有很大程度的影响,其次为滑石粉含量,当滑石粉含量增多时,相似材料黏聚力逐渐增大;滑石粉含量为相似材料内摩擦角的主要控制因素。试验方法和结果可为其他模型试验中土质相似材料的配比提供参考。

Experimental Study on the Proportion of Similar Materials of Silty Clay on the Terraces of the Yangtze River

In order to determine the proportion of silty clay similar materials on the terraces of the Yangtze River,the ratio of raw materials is studied.Based on a three-factor and three-level orthogonal test design method,using talcum powder,bentonite,quartz sand and water as raw materials,it is equipped with silty clay similar materials in the foundation pit model test.Then,the two physical and mechanical indexes of cohesion and internal friction angle of nine sets of proportioning schemes are obtained through the shear test.In addition,the sensitivity and significance of each factor are analyzed by the range method and the variance method,and the influence of talcum powder,bentonite,quartz sand and water content on cohesion and internal friction angle is investigated.The research results are:the analysis results of the range method and the variance method are consistent,and the two methods can reasonably judge the sensitivity and significance of each factor to the inspection index.Although the amount of bentonite is small,it has a great influence on the cohesion of the soft soil layer,followed by the content of talcum powder.When the content of talcum powder increases,the cohesive force of similar materials gradually increases.Moreover,the content of talcum powder is the main controlling factor for the internal friction angle of similar materials.The test process and results provide a reference for the proportion of similar soil materials in other model tests.