海滨深厚填石层止水帷幕咬合桩施工技术

Secant Pile Slurry Wall Construction in Soft Soils with Stone Fills

以深圳蛇口邮轮中心基坑为例,通过对深厚抛石填石层中采用高压旋喷注浆、常压注浆、灌注桩咬合桩形成的止水帷幕进行现场渗透试验结果分析比较,确定在临海深厚填石层中采用＂冲孔灌注塑性混凝土桩＋钢筋混凝土桩＂咬合桩止水方案能满足基坑止水帷幕设计要求。针对深厚填石层、地下水与海水联通的特殊情况,简要介绍了施工关键技术。监测和检测结果表明,＂冲孔灌注塑性混凝土桩＋钢筋混凝土桩＂咬合桩止水效果良好,可靠度高,对类似工程具有较高的参考价值。

This paper presents a case study of a secant pile slurry wall construction for the deep excavation of Shekou Cruise Center in Shenzhen.In the thick stone fills in near shore soft cohesive layers,the slurry walls are usually installed by using high or regular pressure jet grouts and secant piles.Compared with different wall types,it is concluded that the combination of cast-in-place lean concrete pile with the reinforced concrete piles could meet the design requirements.This paper presents the unique construction procedure in the subsurface conditions of thick stone fills and the brackish groundwater.The results indicate that the second pile is a reliable and efficient slurry wall type.