水泥土截渗墙钻孔注水试验理论及应用

基于杜布依假设和恰尔内伊渗流理论,将钻孔注水试验推广应用于有限宽度的水泥土截渗墙,利用Schwarz-Christoffel变换,给出了水泥土截渗墙常水头和降水头两种条件下的钻孔注水试验渗透系数计算公式。某工程水泥土截渗墙围井试验、常水头钻孔注水试验和降水头钻孔注水试验结果表明,三种方法测得的渗透系数均在同一个数量级上,常水头钻孔注水试验与降水头钻孔注水试验结果基本相同,而围井试验结果约为钻孔注水试验结果的2倍。考虑到桩体搅拌均匀程度、搭接厚度、环境等因素对围井试验的影响,认为三者测试结果基本一致,验证了水泥土截渗墙钻孔注水试验计算公式的合理性。

Theory of water injection test in borehole for cement-soil impermeable wall and its application

Based on Dupuit hypothesis and Qiaerneiyi seepage theory， the water injection test in borehole is applied to the finite-width cement-soil impermeable wall， and then Schwarz-Christoffel transformation is adopted to give the formulas for calculating the permeability coefficients of the water injection tests in borehole for the cement-soil impermeable wall under the conditions of both the constant head and the falling head. The results of the enclosed well test， the constant head and the falling head water injection tests in borehole made for the impermeable wall of a project show that the permeability coefficients measured by these three methods are of the same order of magnitude and the results from both the constant head and the falling head water injection tests in borehole are basically the same， while the permeability coefficient of the enclosed well test is two times the permeability coefficient of the water injection test in borehole. In view of the impacts from the mixing uniformity of pile， the overlapping thickness and the environmental factors on the result from the enclosed well test， it is considered that the results from these three test methods are basically identical and the reasonableness of the formulas of water injection test in borehole is verified as well.