A Freeze-Thaw Fatigue Damage Model for Granite Tunnels

摘要

After subject to freeze and thaw cycles, tunnels will be damaged. To figure out such damage and its mechanism, this study carried out freeze-thaw cycle test to simulate the natural environment of tunnels, and took the physical properties of granite rocks sampled from the granite tunnels as the test parameters. In the test, the macroscopic changes of the rock samples before and after freeze-thaw cycles were observed, and the internal damages of the rock samples were analyzed. Then, this paper regarded freeze-thaw cycles as a type of low-cycle fatigue, and defined a damage variable based on the dynamic modulus of elasticity to study the fatigue damage model established for granite tunnels. At last, the comparison of the model simulation results and test results of granite tunnels proved the effectiveness of the proposed model in engineering practice.