The Study on Mechanical Properties of Karst Tunnel
Several numerical models were built by FLAC3D to simulate tunnel with karst around spandrel, tunnel with karst around springe, tunnel with karst around inverted arch and tunnel with karst around side wall. The influence of karsts on the deformation of lining and the safety coefficient distribution of surrounding rock after excavation was analyzed. The results from the numerical modeling suggest as follows: karst around spandrel has extremely unfavorable effect on the deformation of lining and the safety of surrounding rock above the vault, karst around side wall also seriously affect the stability of tunnel due to the asymmetry pressure on tunnel caused by karst, consequently, auxiliary measures should be taken to handle these two cases; karst around springe and karst around inverted arch has limited adverse influence on the overall safety of tunnel, backfill measures are enough to handle these two cases.
Chaohe Chen, Yong Huang and Guangfan Li
B. Li and T. Y. Qi, "The Study on Mechanical Properties of Karst Tunnel", Advanced Materials Research, Vols. 243-249, pp. 3399-3402, 2011