摘要
黄土自重湿陷量计算值与实测值往往存在较大差异,黄土自重湿陷系数室内测定方法存在理论上的不足是产生这种差异的主要原因之一,改进和完善黄土自重湿陷系数测定理论和方法已成为正确评价黄土地基的迫切要求。在前期研究的基础上,以土的干密度、含水量、粒间作用和天然自重压力等为因素,对影响黄土自重湿陷系数的因素进行试验研究。将改进法与现行室内方法测定的自重湿陷系数的比值Rc与因地区土质而异的修正系数β0进行比较,分析改进法的合理性,探索各因素对二者测定结果差异的作用规律。研究表明:上覆土压力、土的干密度、含水量和粒间作用对Rc均有不同程度的影响,干密度是最重要的影响因素,含水量和上覆土压力次之,粒间作用最小。改进法可减小土样扰动对自重湿陷系数测定值的影响。
There is a great difference between the calculated collapse under overburden pressure and the measured collapse,it is one of the main reasons for the difference that the method indoor for determining coefficient of collapsibility under overburden pressure has theory deficiency,it has become an urgent requirement how to correctly evaluate loess foundation improving the theory and method for determining coefficient of collapsibility under overburden pressure.An improved method for determining coefficient of collapsibility under overburden pressure was established in the literature No.10,based on which taking dry density,moisture content,interparticle force and natural weight pressure as factors,the problems of determining coefficient of collapsibility under overburden earth pressure were studied by experiment.The rationality of the improved method was analyzed,and the influencing rule of each factor on the difference between the two determination results was explored by comparison of Rcand β0,Rc was the ratio of coefficient of collapsibility under overburden pressure determined by the improved method and current method,β0was the correction coefficient varied with the soil.Research showed that the overburden pressure,dry density,water content and interpartical force had different effects on Rc,dry density was the most important factor,water content and overberden pressure were the less ones,and the interpartical force was the minimum.The improved method had general applicability and theoretic rationality,which could reduce the effects of soil disturbance on coefficient of self-weight collapsibility.
引文
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