在模拟矿山开采引起的岩层运动时,将光纤传感器埋入模型的岩层中,研究采用光纤传感技术监测岩体变形的理论和技术。提出一种基于光时域反射技术的分布式光纤传感系统和一种新的测试方法,设计出新型光纤微弯传感器,该传感器既可以实现微弯,又可以实现宏弯。通过 2 m 相似材料模型实验,验证了光纤测试岩梁变形的可行性。
Presented the fiber Bragg grating (FBG) sensors for rock strain monitoring in the 1.2 m long plane stress model of the simulation experiment. In the past, for the lack of appropriate technique to measure the deformation of rock structures, the measurement of deflection was restricted to just a few discrete points along rock, and the measuring points were limited to the location installed with displacement transducers. We developed a method to monitor the deformation of rock structures using fiber optical Bragg grating strain sensors. The sensors were embedded in rock layers of simulation experiment before the materials were put in. These sensors were then used to monitor the experienced strain with different face advancing distance. The test results indicate that, if properly installed, FBG sensors can survive under severe conditions associated with embedment process and yield accurate measurements of strains response. At the same time, we make comparisons of the data obtained by FBG sensors with those by centesimal gauge. The interest in FBG sensors was motivated by the potential advantages that they can offer more than existing sensing technologies.