岩土工程学报2012，Vol.34Issue(7)：1313-1319,7.
饱和砂土三轴试验中反压设置与抗剪强度的研究
Effects of back pressure on shear strength of saturated sand in triaxial tests
摘要
Abstract
The back pressure saturation method is commonly adopted in triaxial tests to increase the saturation degree of samples. But the value of the back pressure is not stipulated in Chinese standards nowadays. To investigate the back pressure effects, a series of triaxial tests are carried out on Fujian standard sand. The stress-strain relationship of saturated soils under different back pressures and confining pressures is analyzed, and the development of pore pressure is obtained. The effective friction angle obtained from different failure criteria are also deduced. The test results reveal that the back pressure plays an important role in the undrained shearing behaviors of dilative soils, however, it seems to produce no effect on drained condition. According to the test results, it is suggested that, the back pressure should be 300~500 kPa, and be equal in one series of tests. In undrained shear test the strength corresponding to the maximum effective principal stress ratio （1/3）max is recommended as the maximum undrained shear stength. While the residual stress of soils needs to be considered, Au=0 （excess pore pressure equal to zero） could be the failure criterion.关键词
反压/剪胀性/抗剪强度/三轴试验Key words
back pressure/dilatancy/shear strength/triaxial test分类
建筑与水利引用本文复制引用
黄博,汪清静,凌道盛,丁浩,陈云敏..饱和砂土三轴试验中反压设置与抗剪强度的研究[J].岩土工程学报,2012,34(7):1313-1319,7.基金项目
地震行业科研专项 （）
国家自然科学基金项目 （）
国家重点基础研究发展计划项目 （）
