土石围堰防渗墙快速施工时泥浆渗透特性及渗透系数反演方法研究

Research on the Inversion Method of Mud Permeability Coefficient during theConstruction of Earthwork Cofferdam Seepage Control Wall

土石围堰防渗墙施工过程中的固壁泥浆具有一定的防渗能力。如果工程中出现一些突发事件严重影响施工进度,为了确保主体建筑物施工进度,工程中可以采用围堰防渗墙施工过程中提前进行基坑抽水的施工策略,但此时固壁泥浆的防渗能力以及堰体稳定是否满足要求还有待研究。利用ABAQUS有限元计算软件,以渗流量为评价参数,研究了围堰不透水层深度、泥浆渗透系数以及泥浆影响带对围堰防渗能力的影响。并在此基础上,提出了基于围堰渗流量的泥浆渗透系数反演方法,为围堰防渗墙施工与基坑提前排水同时进行的施工策略研究提供了重要的依据。研究成果可为类似工程提供参考。

During the construction of earthwork cofferdam seepage control wall,solid wall mud has certain seepage control function.If some emergencies occur in the project that seriously affect the construction progress,in order to ensure the construction progress of the main build⁃ing,the project can use the construction strategy of pit pumping in advance during the construction of cofferdam impermeable wall.But at this time,the impermeability of the solid wall mud and the stability of the weir body to meet the requirements remain to be studied.In this pa⁃per,ABAQUS finite element calculation software is used to research the influence of depth of impermeable layer of cofferdam,mud permea⁃bility coefficient and mud influence zone on the seepage control ability of cofferdam by taking seepage volume as evaluation parameter.On this basis, the inversion method of mud permeability coefficient based on the seepage flow volume of cofferdam is proposed, which providesan important basis for the research on the construction strategy that the construction of cofferdam impermeable wall is carried out at the sametime with the advance drainage of foundation pit. The research results can provide reference for similar projects.