TRD工法水泥土墙现场取芯的三轴渗透试验

Triaxial permeability test for site coring of cement-soil wall by TRD method

为提高TRD工法在国内的应用水平,通过对天津市某基坑项目TRD水泥土墙进行现场取芯,在实验室内进行三轴渗透试验,得出水泥土墙在不同水泥掺入比条件下的芯样渗透系数曲线、不同养护龄期条件下芯样的渗透特性关系和不同土层条件下的芯样渗透系数对比,并分析产生上述曲线关系的原因,得出满足基坑止水要求的水泥经济掺入比和合理的养护龄期,给出了不同龄期下TRD水泥土墙渗透系数与水泥掺入比的经验公式.结果表明,TRD工法优于传统的SM W工法.

In order to improve the domestic application level of TRD method,a triaxial permeability test was performed in the laboratory through the site coring of TRD cement-soil wall in a certain foundation pit project in Tianjin. The permeability coefficient curve of cement-soil wall samples under different cement mixing ratio conditions,the relationship of permeability characteristics of samples under different curing age conditions and the comparison in the permeability coefficients of samples under different formation conditions were obtained. In addition,the generating reasons for the relationship of these curves were analyzed,and both economic cement mixing ratio and reasonable curing age that could satisfy the water stop requirement of foundation pit were proposed. An experience formula for both permeability coefficient of TRD cement-soil retaining wall and cement mixing ratio under different age was given. The results showthat the TRD method is prior to the traditional SM W method.