Seismic damage mechanism and treatment technologies of construction landslide section of highway tunnels in highly seismic region

In the general section of highway tunnels, the seismic damage, which makes lining collapse, universally occurs in the construction landslide section during Wenchuan Earthquake. Based on the seismic damage survey data of the general section of highway tunnels, it is meaningful to analyze the seismic damage characteristics, seismic damage mechanism and treatment technologies of the construction landslide section of highway tunnels suffering intense earthquake. The seismic damage characteristics of the construction landslide section of highway tunnels in Wenchuan Earthquake regions reveal that the secondary linings in the construction landslide section of weak wall rock suffer collapse or even overall collapse in serious section. The seismic damage mechanism of the construction landslide section of highway tunnels is that the earthquake inertia force is significant and the forced displacement has small influence. After the measure of backfilled grouting and staggered construction joint in the landslide section of highway tunnels in the highly seismic region, the damping rates of the principal stresses and internal forces are all above 35%. It is shown that the processing is effective to the construction landslide section of highway tunnels to improve the anti-seismic capacity. The research results are of important singnificance to the anti-seismic technology in the communication of lifeline engineering in high-intensity earthquake moutainous areas.