Abstract：The crack of lining caused by rheological effect of surrounding rock is a problem that is easy to encounter during service period of tunnel in weak rock stratum. To solve this problem, a weak and crushing phyllite tunnel is taken as an example. Based on the survey on crack conditions and causes of secondary lining, two models are established: rheological model of anchor-rock composite structure and crack model of secondary lining based on shell-joint. For different damage degrees, different crack positions and different quantities of cracks of secondary lining, long-term safety of structure is analyzed. The results show that, under action of a single crack, the safety factor of tunnel is gradually reduced with the increase of the crack depth. The safety factors for vault, spandrel and haunch may decrease almost linearly, while the decrease of safety factor for vault is most significant. Compared to the cracked sections, uncracked sections are more sensitive to rheological load due to the high stiffness. The safety factors of uncracked sections may decrease more remarkably with the increase of service life, and the safety factors of some sections may even be reduced to below 1. When η (damage degree) is greater than 0.7, the safety of structure is mainly controlled by rheological load. When η is between 0.5 and 0.7, the safety of structure is controlled by rheological load and damage degree. When η is smaller than 0.5, the safety of structure is mainly controlled by damage degree. In practical applications, when two cracks occur in secondary lining, strengthening the structure is appropriate when η is equal to 0.5. While three cracks occur in the structure, strengthening the structure is appropriate when η is equal to 0.7.
徐国文 何川 汪耀 汪波. 流变荷载作用下隧道裂损二次衬砌结构安全性能研究[J]. 土木工程学报, 2016, 49(12): 114-123.
Xu Guowen He Chuan Wang Yao Wang Bo. Study on the safety performance of cracked secondary lining under action of rheological load. 土木工程学报, 2016, 49(12): 114-123.
