In a fiber strain sensing system

strain sensing cable is usually used as sensing organ instead of bare fiber. High stress transfer performance of strain sensing cable is required to provide qualified accuracy and sensitivity. In a strain sensing system which contains strain sensing cable

the detected strain is the strain of the fiber. This strain can’t directly reflect the actual stress on the sensing cable. This paper has established theoretical models of tightly jacketed sensing cable and reinforced sensing cable based on elasticity mechanics

combining Lame formula and Generalized Hooke's Law. Meanwhile

this paper has proceeded simulation experiment on samples of these two typical types of sensing cables

using BOTDR to detect the strain of the cables. The results of theoretical calculation match the experimental measurement

the linear rate of all the results are more than 97%

the differences of the slope between theoretical calculation match the experimental measurement are less than 8%

which proves the model in this paper is effective.