Model tests on damping of shock absorption layer of stick-slip fracture tunnel in highly seismic areas

To improve the anti-seismic performance of tunnels in highly seismic areas with stick-slip fracture, the strong earthquake vibration dynamic tests on the damping layer of large static bond-slip with different thicknesses are performed based on the section of F8 stick-slip fracture in Longxi tunnel of Dujiangyan-Wenchun expressway under earthquake action. The shock absorption technology is used for the damping layer. The results show that under the action of earthquake, the fault rupture dislocation has greater influence scope and degree on the upper part of the tunnel than on the lower part of the tunnel. The plate part is the focus of the earthquake resistance design. The damping effects of 10 cm thick-shock absorption layer of the tunnel are obviously better than those of 5 cm thick and 15 cm thick shock absorption layers. The 10 cm thick shock absorption layer is thus recommended. The research results may provide the technical support for improving the anti-seismic performance of tunnels across dangerous mountains with stick-slip fracture.