地下水渗流沉降的三维耦合模型及程序的研制

Three-dimensional coupled models of groundwater seepage and land-subsidence and development of computer program

研制可合理模拟预测基坑降水过程中引起地面沉降的计算机程序,并提出最优化降水方案。基于三维全耦合数值模型,笔者开发了GWS软件。GWS软件是以比奥固结理论为基础,将土体的非线性特征及土的渗透性随应力状态的动态变化考虑进去,通过耦合地下水渗流场和土体应力场进行模拟预测基坑降水过程中渗流场及地面沉降的变化。以一个实际基坑降水工程为例,经GWS软件计算得出5口井联合抽水方案,后续工程证明此方案正确、可靠。以三维全耦合数值理论为基础的GWS软件,可以为基坑降水工程引起的地下水渗流场变化及地面沉降量提供可靠的预测。

A computer program which can reasonably simulate and forecast the land subsidence caused by foundation pit dewatering was developed in the paper, with an optimal plan of dewatering presented. Based on the three-dimensional coupled numerical model, the writers developed a GWS software. On the basis of Biot＇s consolidation theory, the GWS software can simulate and forecast the change of seepage and land subsidence in the process of foundation pit dewatering, which considered the non-linear characteristics of soil and the dynamic change of permeability coefficient with the stress state. Taking a practical foundation pit dewatering project for example, a plan of simultaneous operation of five extraction wells was obtained by calculation of the GWS software. The plan was proved to be correct and reliable by follow-up project. The GWS software which is based on the threedimensional coupled numerical model could provide reliable forecast for the change of seepage and land subsidence caused by foundation pit dewatering.