56m深TRD工法搅拌墙在深厚承压含水层中的成墙试验研究  

Experimental investigation of construction of a 56m deep constant thickness cement-soil wall using trench cutting re-mixing deep wall (TRD) method in deep aquifers

作　　者：王卫东 翁其平 陈永才 

机构地区：[1]华东建筑设计研究总院地基基础与地下工程设计研究中心,上海200002 [2]上海基坑工程环境安全控制工程技术研究中心,上海200002

出　　处：《岩土力学》2014年第11期3247-3252,共6页Rock and Soil Mechanics

基　　金：国家科技支撑计划(No.2012BAJ01B02);上海市建交委科研项目(建管2013-009-009);上海市科委工程技术研发中心平台建设项目(No.13DZ2251400)

摘　　要：上海国际金融中心项目基坑面积约为48 860m^2,开挖深度为26.5~27.9m,周边环境复杂。为控制抽降承压水对周边环境的影响,经方案比选,基坑周边设置厚700mm、深56m等厚度水泥土搅拌墙（TRD）作为承压水悬挂隔水帷幕。在上海地区施工如此深TRD墙体尚属首例,为此现场开展了试成墙试验,试成墙监测表明,墙身在深厚承压含水层中水泥土强度达到0.84~1.38 MPa。室内渗透性试验表明,渗透系数由10-3cm/s提高到10-7cm/s,满足隔水帷幕设计要求;墙体施工期间,地表最大沉降约8mm,主要影响范围约5m;土体侧向位移主要产生在距离墙体5m的范围内,TRD墙体施工对周边环境影响很小。试验墙体的顺利实施为后续正式墙体的施工提供了依据,也为类似工程提供了重要参考。The excavation area of Shanghai International Financial Center, whose surrounding environment is complex, is 48 860 m2. The depth of the excavation ranges from 26.5 to 27.9 m. In order to minimize pumping effects of confined water on the surrounding environment, a 700 mm thick and 56 m deep constant thickness cement-soil wall has constructed as a watertight screen along the periphery of the excavation. As the first time to construct such a deep TRD wall in Shanghai, a series of tests had carried out on the site. The monitoring results show that the strength of the cement-soil wall has ranged from 0.84 MPa to 1.38 MPa in the deep aquifer. Laboratory permeability test results show that the permeability of the wall is increased from I0 3 cm/s to 10,7 cmJs. Both strength and permeability of the wall satisfied the design requirements for a watertight screen. During construction of the wall, the maximum surface settlement is about 8 mm and the main influence zone is approximately 5m away from the wall. It is also observed that lateral soil displacements mainly took place within 5 m from the wall. Therefore, the influence of the wall construction on the surrounding environment is negligible. The test results provide references for subsequent construction of the TRD walls and serve as a case study for similar projects in Shanghai as well.

关 键 词：基坑 等厚度水泥土搅拌墙 TRD工法 隔水帷幕 承压水 

分 类 号：TU471[建筑科学—结构工程]