一体式水位自动化传感器在轨道交通基坑监测中的应用

Application of Integrated Water Level Automation Sensor in Monitoring of Rail Transit Foundation Pit

轨道交通工程基坑地下水位监测中,传统手持式水位计存在着采集效率低、实时性差、无法实现自动化等弊端,而且现有水位自动化设备多采用RS485通讯,存在着数据传输距离近、接线及结构复杂等缺点。在详细研究水位传感器工作原理的基础上,基于MCU设计,自主研发具有高集成度的一体式水位自动化传感器,利用PowerBus接口及MODBUS协议,实现水位传感器与采集模块的数据通信;并采用低功耗休眠模式,对轨道交通工程基坑地下水位实现超长时间连续监测,以满足基坑现场监测工况要求。在某轨道交通工程基坑地下水位监测项目中,将一体式水位自动化传感器与人工手持水位计获取的数据进行对比分析,结果表明,一体式水位自动化传感器获取的水位数据稳定可靠,采集的数据绝大部分误差均在20 mm以内,与手持水位计测量精度相当,能够满足轨道交通工程基坑监测项目中地下水位监测的应用需求。

In response to the drawbacks of low collection efficiency,poor real-time performance,and inability to achieve automation in traditional handheld water level sensors for underground water level monitoring in rail transit engineering foundation pits,as well as the fact that existing water level automation equipment mostly uses RS485 communication,which has disadvantages such as short data transmission distance,complex wiring and structure,this paper conducted a detailed study of the working principle of water level sensors and independently developed an integrated water level automation sensor with high integration based on MCU design.By using PowerBus interface and MODBUS protocol,data communication between the water level sensor and the collection module was achieved.Low power consumption sleep mode was adopted to achieve ultra long continuous monitoring of underground water level in rail transit engineering foundation pits,meeting the requirements of on-site monitoring conditions of foundation pits.In the groundwater level monitoring project of a certain rail transit engineering foundation pit,the groundwater level data collected by the integrated water level automation sensor was compared and analyzed with the data obtained by a manually held water level gauge.The results shows that the data accuracy collected by the integrated water level automation sensor is better than 20 mm,which can meet the monitoring requirements of the groundwater level in the foundation pit.