饱和粉土孔隙水压力性状试验研究

Test study on pore water pressure mode of saturated silt

采用多功能静动液压剪切仪进行了室内动力循环试验,研究了饱和重塑粉质土孔压变化规律。其特殊之处在于试验是在达到液化标准后继续施加动荷载直至孔压平稳为止。这个过程模拟了液化后严重破坏情况以及孔压发展的完整过程。研究发现,粉质土孔压可以用一个改进的指数形式来描述。该表达式能拟合较多的前人研究孔压成果,而且弥补了前人研究成果中可能出现的极限孔压比围压大的缺陷。理论分析和数据验证都表明该表达式具有较好的适用性。

In order to investigate the regulation of pore water pressure of silty soils, a series of dynamic cyclic tests on saturated and disturbed silt were carried out in a new universal triaxial torsional shear apparatus of Hohai University. The special was that the tests didn＇t complete when the initial liquefaction appeared until the pore water pressure had been in a smoothly way, which could simulate the severity of liquefaction after liquefaction and also describe the whole process of pore water pressure generation. It is found that the regulation of pore water pressure curve can be fitted by an improved exponential function. The function can fit much achievements of other scholars and also make up the limitation that pore water pressure is larger than confining pressure. Both theoretical analysis and test data validation indicate the applicability of the pore water pressure expression.