Abstract:
It is neccessary to study earthquake damage to highway tunnels in earthquake-affected areas with different seismic intensities for scientific design and earthquake fortification. Based on the earthquake-damage information regarding highway tunnels in Wenchuan, the above-mentioned study was carried out. The results show that: a tunnel was not destroyed in the area of 6-degree seismic intensity; the tunnel entrance and tunnel slope structure were smashed by rockfalls in the area of 7-degree seismic intensity; there was almost no lining damage to a hard-rock tunnel body in the area of 8~11-degree seismic intensity; slight cracks and water penetration occurred at the lining of a soft-rock tunnel body in the area of 8-degree seismic intensity; reticular cracks and large-area water penetration, concrete spalling, falling, and secondary lining collapse occurred at the lining of a soft-rock tunnel body in the area of 9-degree seismic intensity; a tunnel portal was blocked by sliding and collapse of the slope around the tunnel entrance in the area of 9-degree seismic intensity; increased secondary lining collapse occurred at the soft-rock tunnel body in the area of 10-degree seismic intensity; and surrounding rock collapse occurred at a soft-rock tunnel body in the area of 11-degree seismic intensity. These research results are significant to further study of the earthquake-damage mechanism and countermeasures for highway tunnels in earthquake-affected areas with high seismic intensity.