基于光纤光栅技术的坑底隆起监测装置与应用初探

Preliminary study on the monitoring device for pit bottom heave based on fiber Bragg grating technique and its application

基坑开挖过程中实时监测坑底隆起量对于掌握基坑隆起特征,指导基坑安全施工具有重要的现实意义。基于光纤光栅感测技术,根据光线光栅位移计拉杆式的工作特点,研制了一套坑底隆起变形监测装置,通过拉杆传动原理将土体隆起变形转换为光纤光栅位移计的拉伸变形实现隆起量监测,基坑工程现场监测结果与传统基坑回弹监测结果基本吻合。该装置能够实现远程监测操作,监测频率高,测量速度快,为坑底隆起自动化智能监测提供了设备条件。

In the process of deep excavation,it is significant to monitor the bottom heave of the excavated pit in real time in order to find the heave characteristics and guide the safe excavation.Based on the fiber Bragg grating technique and the draw-line displacement sensor working characteristics,a device is developed to monitor the basal heaves of excavated pit.The soil heave is transformed into the tensile deformation of fiber Bragg grating displacement sensor by the pulling rod.The monitored results of the pit are generally consistent with the conventional monitoring results.The remote operation and monitoring can be realized frequently and quickly with the device.The equipment could be used in the automatic intelligent monitoring of the pit bottom heave.