考虑涂抹区渗透系数变化的砂井地基固结解

Analytical solution for consolidation of sand-drained ground considering variation of permeability coefficient in smeared zone

针对砂井打设对井周土产生的不同程度扰动,推导基于等应变假设的考虑水平渗透系数沿径向变化的固结控制方程,得到一般解.根据实际工程中可能出现的情况建立5种渗透系数变化模式,在一般解的基础上得到了相应固结解,在现有等应变条件下的砂井地基固结解是本文解特例.计算分析表明,涂抹区渗透系数变化及具体变化模式对砂井地基固结性状均有重要的影响,在相同的可比条件下,模式2对应的固结最快,模式4对应的固结最慢.

A control consolidation equation considering variation of horizontal permeability of soil in smeared zone was derived based on the equal strain condition for the different disturbances toward soil surrounding vertical drains during construction. The general analytical solution was developed. Five possible variation patterns of the horizontal permeability coefficient of soil in smeared zone were proposed based on the practical condition, and corresponding consolidation solutions were obtained from general solutions. Results show that the existing consolidation theory for sand-drained ground under equal strain condition is a special case of the solutions given herein. The influences of the variation and variation pattern of horizontal permeability of soil in smeared zone on the consolidation behavior of sand-drained ground are both significant. The rate of consolidation corresponding to pattern II is the greatest while that corresponding to pattern IV is the least under comparable condition.