振冲前后高湿度黄土固结不排水剪的归一化性状

本文通过三轴固结不排水剪切试验,探讨了某场地欠压密至正常压密的高湿度黄土在受振动水冲法施工前后的应力应变的归一性及孔隙水压力的变化规律。理论与实验分析表明:这种黄土在应力水平大于第二拐点值时也能归一,且振冲前后可近似取同一归一参数;用总应力法或有效应力法归一时,偏应力项宜取固结压力的n次幂作为归一变数;Henkel和Wade的孔压计算式中八面体剪应力项前的系数应取为归一变数和八面体剪应力等的函数。本文所得结果和分析方法可广泛适用于高湿度黄土及软土地基。

Normalized Behaviour of CU-Tests for Highly Wetted Loess before and after Being Vibroflotated

In this paper,the normalized behaviour of stress-strain property,and the variation of pore water pressure for a highly wetted,underconsolidated to normally consolidated malan loess before and after being vibroflotated are studied through consolidated undrained triaxial compression tests.Theo- retical and experimental studies demonstrate that,when the stress level is greater than that at the sec- ond inflection point,the loess can be normalized,and the normalized parameter before and after being vibroflotated could approximately be regarded as the same value,and that the power of consolidation pressure should be used as the normalized variant for deviatoric stress,whether the total stress or effec- tive stress normalization procedure is adopted.Instead of a constant,the coefficient before the octahe- dial shear stress for calculating the pore water pressure suggested by Henkel and Wade(1966),should be a function of normalized variant and octahedral shear stress.