光纤光栅静力水准仪设计

Design of a Static Level Instrument Based on Fiber Grating

为了监测岩土的沉降,设计了一种新型光纤光栅静力水准仪装置,用于实时监测岩土地层的变化。根据岩土地层运动情况和已有的静力水准仪结构设计,基于连通器原理,考虑静力水准仪结构、光纤光栅粘贴位置和粘贴方向等因素,推导了静力水准仪在岩土地层工作时的监测原理。搭建了模拟地层沉降的试验装置,验证静力水准仪装置的可行性,实现了对模拟岩土沉降情况的实时监测。通过试验可知,光纤光栅静力水准仪反应迅速,灵敏度为20.877 2 pm/mm,重复性好。独特的光纤光栅粘贴位置和粘贴方向使得整个传感器具有温度自补偿功能,排除了昼夜温差对传感器准确度的影响,扩大了该静力水准仪的使用范围。该静力水准仪可以实现对岩土地层的方便、快捷、全天候、低成本监测,具有广阔的应用前景。

In order to monitor the settlement of rock and soil,a new type of static level instrument based on optical fiber grating isproposed for monitoring the geotechnical changes in real.time.According to the rock stratum movement and the existing structuraldesign of static level instrument,based on the law of the connected vessels,considering the factors of static level structure,theposition of the fiber grating pasted and the direction of pasting.The monitoring principle of the static level instrument working inthe rock formation is deduced.A test device for simulating ground subsidence is set up to verify the feasibility of the static levelinstrument,and achieve real.time monitoring of simulated rock settlement.Through the tests,it is found that the fiber grating staticlevel instrument responds rapidly,with a sensitivity of 20.877 2 pm/ mm and good repeatability.The unique position and directionof the fiber grating paste enable the entire sensor to have a temperature self.compensation function,which eliminates the influenceof the temperature difference between day and night on the accuracy of the sensor and expands the scope of use of the static levelinstrument.This static level instrument can achieve continuous,rapid,weather.proof,low.cost monitoring of the rock formation,andhas broad application prospects.