J. Chai, S.M. Wei, X.T. Chang, J.X. Liu
College of Energy Science and Engineering, Xi’an University of Science and Technology,China

Int. J. Rock Mech. Min. Sci. Vol. 41, No. 3

Abstract: This paper elaborates the application of fiber optic al sensors for monitoring rock structures to provide an internal measurement. Recent structural failure and damage associated with earthquakes, pipeline ruptures, and railroad bridge barge impact, have underscored the need for structural integrity monitoring systems using distributed fiber optical fiber sensors. The fiber optical sensor has potential advantages for the safe monitoring sensor of structures: (i) unlimited length of gage, (ii) applicability to dynamic measurement, and (iii) less affected by temperature. To find the relationship between the bending loss of fiber and the changeable characteristic and premonitory information during the course of the beginning and developing of rock damage, a distributed optical fiber sensing technique based on the optical time domain reflectometer (OTDR) is presented in this paper, and a new sensor designed. By the simulation experiment with analogy material for mining, the sensor is embedded in the rock layer of the model. And the theory and technology for detecting rock failure, and the interaction mechanism of the fiber with the material are studied.

Key Words: Simulation experiment; Rock deformation and damage; Distributed fiber optical sensing; OTDR; Snakelike fiber optical sensor (SFOS); Bending loss


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