作者：杨强1,2,3, 洪成雨1,2,3, 许承恺1,2,3, 孙晓辉1,2,3, 韩凯航1,2,3
作者单位：1. 深圳大学土木与交通工程学院，广东 深圳 518060;
2. 深圳市地铁地下车站绿色高效智能建造重点实验室，广东 深圳 518060;
3. 深圳大学未来地下城市研究院，广东 深圳 518060
关键词：光纤布拉格光栅;土工格栅;边坡试验;数值模拟
摘要：
该研究利用光纤布拉格光栅（fiber Bragg grating, FBG）传感器应变传递模型推导光纤与土工格栅之间平均应变传递系数的解析解，并基于此设计一种半紧套式传感结构。此结构将FBG传感器固定在土工格栅上，实现传感器与土工格栅之间的协调变形，且不因土体变形而发生破坏。为验证其实用性，进行室内边坡模型加载试验，结果表明：随着荷载的增加，土工格栅产生的应变呈现分段线性变化且模型上部土工格栅对荷载变化更为敏感。为验证试验结果的准确性，采用GEO-STUDIO软件对加载过程中土工格栅所产生的应变进行数值模拟分析，结果显示：试验值与模拟值之间的平均误差为9.2%，验证使用FBG传感器进行土工格栅受力测量的可行性。
Study on geogrid-reinforced slope monitoring based on fiber Bragg grating sensors
YANG Qiang1,2,3, HONG Chengyu1,2,3, XU Chengkai1,2,3, SUN Xiaohui1,2,3, HAN Kaihang1,2,3
1. College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, China;
2. Shenzhen Key Laboratory of Green, Efficient and Intelligent Construction of Underground Metro Station, Shenzhen 518060, China;
3. Underground Polis Academy, Shenzhen University, Shenzhen 518060, China
Abstract: In this study, an analytical solution of the average strain transfer coefficient between fiber and geogrid was derived by using the strain transfer model between geogrid and fiber Bragg grating sensor, and then a semi-tight sensing structure based on it was designed. This structure fixed the FBG sensor on the geogrid to ensure that sensor is deformed synchronously with geogrid and does not failure due to soil deformation. To verify the practicability of the structure, a laboratory loading test on geogrid-reinforced slope model was conducted. The test results indicate that the monitoring points of the internal geogrid of the slope show piecewise linear changes with the increase of the load, and the upper geogrid is more sensitive to the load change. To verify the accuracy of test results, this study utilized GEO-STUDIO to simulate the performance of the reinforced soil slope in the loading process. The results show that the average error between measured strain and calculated results is 9.2 %, which verifies the feasibility of FBG sensor to measure the stress of geogrid.
Keywords: fiber Bragg grating;geogrid;slop test;numerical simulation
2022, 48(12):22-28,34 收稿日期: 2021-08-10;收到修改稿日期: 2021-09-22
基金项目: 国家自然科学基金面上项目(52078303)；国家自然科学基金高铁联合基金项目(U2034204)
作者简介: 杨强(1998-),男,湖南益阳市人,硕士研究生,专业方向为岩土工程监测
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