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 deforma...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.展开更多
Acoustic sensing is nowadays a very demanding field which plays an important role in modern society, with applications spanning from structural health monitoring to medical imaging. Fiber-optics can bring many advanta...Acoustic sensing is nowadays a very demanding field which plays an important role in modern society, with applications spanning from structural health monitoring to medical imaging. Fiber-optics can bring many advantages to this field, and fiber-optic acoustic sensors show already performance levels capable of competing with the standard sensors based on piezoelectric transducers. This review presents the recent advances in the field of fiber-optic dynamic strain sensing, particularly for acoustic detection. Three dominant technologies are identified - fiber Bragg gratings, interferometric Mach-Zehnder, and Fabry-Perot configurations - and their recent developments are summarized.展开更多
基金National Natural Science Foundation of PRC(50374055)Shaanxi Key Lab of Ground Control(02JS43)
文摘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.
文摘Acoustic sensing is nowadays a very demanding field which plays an important role in modern society, with applications spanning from structural health monitoring to medical imaging. Fiber-optics can bring many advantages to this field, and fiber-optic acoustic sensors show already performance levels capable of competing with the standard sensors based on piezoelectric transducers. This review presents the recent advances in the field of fiber-optic dynamic strain sensing, particularly for acoustic detection. Three dominant technologies are identified - fiber Bragg gratings, interferometric Mach-Zehnder, and Fabry-Perot configurations - and their recent developments are summarized.
