Fiber Bragg Grating Monitoring of Full-bolt Axial Force of the Bolt in the Deep Strong Mining Roadway
Fiber Bragg Grating Monitoring of Full-bolt Axial Force of the Bolt in the Deep Strong Mining Roadway
复制标题
深部强采巷道锚杆全轴力光纤布拉格光栅监测
DOI：
10.3390/s20154242
复制
发表时间：
2020-08-01
期刊：
影响因子：
3.9
通讯作者：
Yao, Wenhao
中科院分区：
文献类型：
--
作者：
Wang, Peng;Zhang, Nong;Yao, Wenhao
随着开采深度和强度的增加，锚杆轴力的演化对保证支护的可靠性和安全性越来越重要。针对现有煤矿巷道压力监测方法难以长时间连续监测锚杆轴力的问题，设计了一种基于光纤光栅传感原理的全杆光纤布拉格栅测力螺栓及系统。研究发现，梯形槽是一种相对较好的槽。光纤光栅中心波长偏移量与轴向力之间的线性关系大于0.99，得到了螺栓杆轴向力与光纤光栅波长变化之间的换算公式。实时监测显示，受压前后锚杆的轴力发生了明显变化。轴力分布曲线可分为稳定区、增长区和峰值区。巷道支承压力的影响在工作面前方约130m处，峰值区域在推进工作面的25~35m范围内。锚杆端部的轴向力随锚杆端部的增大而线性增大，自由段的轴向力最大，整体应力基本相同。应用结果证明了FBG全长受力螺栓的可行性和有效性。
With the increase of mining depth and strength, the evolution of bolt axial force is increasingly becoming important for ensuring the reliability and safety of support. To improve the problem of the existing coal mine roadway pressure-monitoring method, whereby it is difficult to continuously monitor the axial force of the bolt over a long period of time, a full rod fiber bragg grating (FBG) force-measuring bolt and system were designed based on the principle of fiber grating sensing. It was found that a trapezoidal groove is a relatively better groove. The linearity between the center wavelength offset of the fiber grating and the axial force was more than 0.99, and the conversion formula between the axial force of the bolt rod and the wavelength change of the fiber grating were obtained. The real-time monitoring revealed that the axial force of the bolt obviously changed before and after compression. The axial force distribution curve can be divided into the stable zone, growth zone, and peak zone. The influence of the roadway abutment pressure was approximately 130 m ahead of the working face, and the peak area was within the 25–35 m range of the advance working face. The axial force of the bolt rod at the end of the anchorage linearly increased with the tail end of the bolt, the axial force of the free segment was the largest, and the overall stress was essentially the same. The application results demonstrate the feasibility and effectiveness of the FBG full-length force bolt.