桩锚支护结构设计及支护结构变形监测分析

Design of Pile-anchor Retaining Structure and the Analysis on Its Deformation Monitoring

摘要:

结合北京一个基坑支护工程，从设计角度就桩锚支护结构在基坑支护中的应用及变形控制进行了阐述。根据受力情况，护坡桩主筋配筋采用不均匀布置方式，结合工程、支护结构特点分段配筋；为了满足基坑安全及现场施工用地，砖墙设计时，在砖墙中部增设混凝土腰梁；护坡桩施工中，运用不同的施工工艺，保证了护坡范围内古树的生命安全。从基坑开挖监测角度，对支护结构顶部水平位移进行了监测，对周边建（构）筑物进行了沉降监测，同时对锚杆进行了检测与监测。结果分析表明，基坑水平及垂直变形量均在设计控制范围内，基坑整体稳定，桩锚支护结构对变形起到了有效的控制作用。

Abstract:

Based on an excavation retaining project in Beijing, the paper describes the application of pile-anchor retaining structure in excavation retaining and the deformation control from the design point of view. According to the stress features and structure characteristics, main reinforcement of slope protection pile is unevenly arranged and segment reinforcement is adopted. Concrete middle beam was added in the middle of brick wall to ensure the excavation safety. In the slope protection pile construction, different construction technologies were used to protect the old trees in the slope protection range. From the excavation point view, horizontal displacement on top of retaining structure and subsidence of surrounding building structures were monitored, and the anchor was tested and monitored. The analysis shows that the horizontal and vertical deformation of excavation are in the scope of designed control range, the foundation pit is of overall stability, the pile-anchor retaining structure has played an effective control effect on the deformation.