刚套管跟进钻凿拔除预应力锚索施工技术

Construction Technology of Rigid Casing Followed by Drilling and Removing Prestressed Anchor Cable

为解决建筑基坑预应力锚索侵入基坑外地下空间,对周边建(构)筑物后续开挖尤其是地铁区间盾构施工造成影响的问题,提出一种基于刚性套管跟进钻凿拔除预应力锚索施工技术,随地下室施工进度逐步换撑后拔除预应力锚索,并对形成的孔洞进行注浆封堵,同时对基坑变形数据进行监测。所提出的技术已成功拔除309根预应力锚索,且基坑变形监测数据稳定,实现了施工周期短、造价低、安全性高的目标。

To solve the problem that the prestressed anchor cable of building foundation pit intrudes into the underground space outside the foundation pit and affects the subsequent excavation of surrounding buildings(structures), especially the shield construction of subway section, a construction technology based on rigid casing followed by drilling and removing the prestressed anchor cable is proposed. With the construction progress of the basement, the prestressed anchor cable is removed after the support is gradually replaced, and the formed holes shall be grouted and blocked,and the deformation data of the foundation pit shall be monitored. The proposed technology is successfully removed 309prestressed anchor cables, and the deformation monitoring data of the foundation pit is stable, which has achieved the goals of short construction period, low cost and high safety.