某复杂平面基坑支护结构水平位移监测及加固

某平面形状复杂的基坑，采用单排人工挖孔桩与单排锚杆相结合的支护结构。在支护结构施工和基坑开挖的过程中，对基坑进行了水平位移监测。监测结果显示，在基坑开挖过程中，某些部位出现了支护结构顶部水平位移过大，超过报警值并持续增加现象，并导致支护结构险情。施工单位加固时未针对险情机制采取处理措施，未取得加固效果。介绍了该基坑支护结构的设计和监测情况，分析了19个点的监测数据，说明了险情发生的机制，并在此基础上提出了加固措施，取得了良好的效果。

Monitoring horizontal displacements of support structure for a complicated planar foundation pit and its reinforcement

The combination of a single row of man-excavation piles and a single-row of anchorage pillars is applied as the support structure for a complicated planar foundation pit. During the construction of the support structure and excavation, horizontal displacements monitoring is carried out for the pit. Monitoring results show that in some parts the tops of support structure, their deformations is larger than the advance warning value and continue to aggravate in the process of the excavation; the support structure is in dangerous state. The construction union don’t take measure against dangerous state and get no effect. The situations of the support structure in design and monitoring condition are described; and the monitoring results of 19 points are analyzed; the mechanism of the dangerous situation is explained; and the reinforcement measures are proposed in light of these existing problems, so as to obtain good effectiveness.