偏压固结下饱和标准砂孔压增量分析

Analysis for pore water pressure increment of saturated standard sand under deviatoric stress consolidation

通过对饱和福建标准砂动三轴液化试验现象的系统分析，提出了一个偏压固结下孔压增量计算公式。分析表明，固结比对饱和砂土液化有重要影响，孔压相对增量与固结比增量之间呈幂函数关系，即△U／U0=C1,a（kc-1）^C1,b。C1,b是一个远小于1的数，平均为0．41，表明孔压增量在kc接近1时降低速度较快，在kc继续增大时降低速度变慢并趋于平缓。G1,a在0．20-0．35之间，平均为0．27，意味着kc=2时的孔压增量较kc=1时降低20％-35％，平均降低27％。

A new incremental formula for evaluating the pore pressure of the saturated sand under the deviatoric stress consolidation is presented by analyzing the dynamic triaxial tests of the Fujian standard sand. The test results indicate that the consolidation ratio has remarkable influence on the pore pressure rise and the relation between the relative increment of the pore pressure and the increment of the consolidation ratio is in the power function form, i. e. , △U/U0=C1,a（kc-1）^C1,b, in which C1,b is much less than 1 and equal to 0.41 on an average. It means that the pore pressure increment decreases rapidly in the beginning and then slows down. C1,a is 0.25 - 0.35, and 0.27 on an average. This indicates that the pore pressure for kc =2 is less by 20% - 35% than that for kc = 1 and is by 27% reduction on an average.