摘要
Based on the theory of fiber Bragg grating sensing, and using a 2 m plane stress material model of the simulation experiment, the wavelength shift regulations of fiber Bragg gratings under rock settlement deformation conditions were got, which provided reliable basis for the design of the wavelength bandwidth of sensing gratings. The wavelength increase when the rock layers are Compressive strain sensitivity is bigger under tension, and decrease under compression. than tensile strain sensitivity when the load is lower. However compressive strain sensitivity is smaller than tensile strain sensitivity when the load is higher. Experimental result coincides well with theory. The wavelength bandwidth of two neighboring fiber Bragg gratings of the gratings used for monitoring the deformation of rock layer should be no less than 6 nm. An effective new approach for detecting the deformation of rock settlement with fiber Bragg gratings is provided.
Based on the theory of fiber Bragg grating sensing,and using a 2 m plane stress material model of the simulation experiment,the wavelength shift regulations of fi- ber Bragg gratings under rock settlement deformation conditions were got,which provided reliable basis for the design of the wavelength bandwidth of sensing gratings.The wave- length increase when the rock layers are under tension,and decrease under compression. Compressive strain sensitivity is bigger than tensile strain sensitivity when the load is lower.However compressive strain sensitivity is smaller than tensile strain sensitivity when the load is higher.Experimental result coincides well with theory.The wavelength band- width of two neighboring fiber Bragg gratings of the gratings used for monitoring the de- formation of rock layer should be no less than 6 nm.An effective new approach for de- tecting the deformation of rock settlement with fiber Bragg gratings is provided.
基金
the National Natural Science Foundation of China(50775060)
