Model tests on effect of dislocation reducing measures of stick-slip fault of tunnels
摘要
Based on a tunnel project, large-scale model tests are carried out on anti-seismic and damping measures for dislocation of stick-slip fault. By analyzing longitudinal strain, contact pressure and safety factor of linings, the anti-seismic and damping effects are comparatively studied under six kinds of working conditions of A (no dislocation reducing measures), B (dislocation reducing layer), C (dislocation reducing joint for secondary lining), D (dislocation reducing joint and increasing thickness for secondary lining), E (interleaving setting of dislocation reducing joint) and F (combined dislocation reducing measures). The results show that the scope of the impact and intensity of stick-slip dislocation on hanging wall is greater than that on footwall. The control effect of the longitudinal deformation from low to high is A << C≈D≈ B < E < F, that of the contact pressure is A << B < D< C ≈ E ≈ F, and that of the structural stress is A <<D< C ≈ E < B < F. The scheme of conditionD under the design concept of being rigid and flexible should not be adopted, and the safety of linings of tunnel after stick-slip can be effectively guaranteed by the combined measures of “dislocation reducing layer and staggered dislocation reducing joint”. The researchresults maybe of important singnificance for the anti-seismic technology in rail communication of lifeline engineering in high intensity earthquake areas.