Evaluation of reinforcement effect of FRP-PCM method in tunnel lining
JIANG Yujing, ZHANG Xuepeng*
State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
Abstract FRP-PCM is a new reinforcing method of tunnel lining using fiber reinforced polymer grid as reinforced material and polymer cement mortar as cementitious material. Based on the finite difference method, a numerical model of tunnel lining with back cavity defect was established. The FRP-PCM method was numerically applied to reinforce the deterioration tunnel lining using. Four design factors including FRP type, loosening pressure, surrounding rock grade and tunnel lining health degree were considered to conduct the numerical simulation. The reinforcement effect of FRP-PCM method on tunnel lining in operation was discussed quantitatively. FRP-PCM reinforcement could improve lining stiffness and strength through arch axial stress and plastic damage of the lining. It could resist the lining deformation to a certain extent, thereby reducing lining failure possibility. The reinforcement effect became more obvious with the improvement of FRP type. In order to quantitatively evaluate the reinforcement effect of the FRP-PCM reinforcement, section repair rate was proposed. Results showed that the higher the degradation level of the tunnel lining was, the more effective the FRP-PCM method was. Besides, suitable type of FRP bars could be selected according to loosen pressure, lining degradation degree and expected section repair rate.
JIANG Yujing,ZHANG Xuepeng. Evaluation of reinforcement effect of FRP-PCM method in tunnel lining[J]. Hazard Control in Tunnelling and Underground Engineering,
2020, 2(1): 11-19.
