基于BDS的毫米级基坑围墙位移监测及告警系统

针对建筑基坑围墙及基坑边坡在建筑物施工过程中发生水平位移和沉降造成安全隐患问题，设计了一种基坑围墙位移监测系统，利用测点定时采集北斗卫星导航系统 (BDS)观测数据，在服务器上结合参考站数据顺序对各个监测点位移监测数据进行处理，最后用休哈特均值控制图，当测点位移量超过阈值时系统发出告警，测点每60 min给出一组测量值，准静态实际测试结果表明:系统能够实现基坑围墙测点东(E)方向为5 mm；北(N)方向为4 mm；天顶(U)方向为9 mm的监测水平. 

A BDS-based millimeter-level foundation pit wall displacement monitoring and early warning system

Aiming at the potential safety hazards caused by the horizontal displacement and settlement of the building's foundation pit wall and the foundation pit slope during the construction of the building, a monitoring system for the displacement of the foundation pit wall is designed. The BeiDou Navigation Satellite System (BDS) observation data is collected regularly by measuring points and combined on the server. The reference station data sequence is used to process the displacement monitoring data of each monitoring point. Finally, the Shewhart mean value control chart is used. When the displacement of the measuring point exceeds the threshold, the system will give an alarm. The measuring point will give a set of measured values every 60 minutes, which is quasi-static. The test results show that the system can achieve a precision of 5 mm in the east (E) direction; 4 mm in the north (N) direction; and 9 mm in the up (U) direction for monitoring.