Abstract: A vertical displacement sensor based on MEMS (Micro-Electro-Mechanical System) and connecting pipe technology was developed for convenience, highprecision, realtime remote monitoring of the vertical displacement. Measurement principle of closed differential pressure connecting pipe displacement was elaborated and the test module was realized. The application performance of closed differential pressure connecting pipe displacement sensor was mainly analyzed from the view of stability and reliability. Initial experiment results show that the resolution of this sensor is higher than 0.1 mm in vertical displacement measurement; the sensitivity is relatively high, with longterm stability 0.3 mm. The daily need for displacement monitoring and measurement is met. It has been successfully applied in bridge deflection measurement of the bridge static load test, which shows that the system has many advantages such as realtime monitoring, low implementation cost, easy to be operated and so on.

Key words: bridge engineering;MEMS vertical displacement sensor system, closed differential pressure connecting pipe, vertical displacement measurement

摘要： 为实现结构竖向位移的便捷、高精度、远程实时测量，开发了一种基于连通管技术和MEMS技术的结构竖向位移测量系统，阐述了封闭差压连通管式位移测量原理及测试模块的实现。重点从稳定性、可靠性角度分析了封闭差压连通管式位移传感器的应用性能，并进行了试验验证。试验结果表明：该位移测量技术及其设备具有优于0.1 mm的竖向位移测量分辨率和较高的灵敏度，长期稳定性0.3 mm，能够满足日常工程测量和在线长期监测项目中的竖向位移测量需求。在桥梁静载试验时的主梁挠度测量中实际应用验证了该系统具有实时测量、布设及操作便捷、低成本等优点。

关键词: 桥梁工程, MEMS竖向位移传感器系统, 封闭式差压连通管, 竖向位移测量