Anti-seismic And Shock Absorption Measures Of Highway Tunnel

Since the establishment of New China,more than seven hundred thousand people died in the earthquake disaster, infrastructure, roads, bridges, tunnels and so many have been seriously damaged, and earthquake since the founding suffered the most devastating earthquake disaster. The earthquake caused a total of up to 21 highway, 18 national and provincial roads, tunnels and 2.4 million km of rural roads, bridges, culverts, slope, embankment and other structures subjected to varying degrees of damage, especially in tunnel damage is particularly serious, affecting the smooth progress of earthquake relief and reconstruction work. Therefore, under this background, research tunnel seismic and damping problem is imminent.In this paper, ANSYS finite element software to establish three-dimensional numerical model to analyze the impact of the tunnel seismic response factors, including the level of surrounding rock, lining thickness, lining elastic modulus. Also studied damping layer thickness, layer elastic modulus and damping effects of different damping layer arrangement of the tunnel damping effect, draw some basic laws.The results show that the level of surrounding rock is the most critical factor in the decisionseismic performance tunnel,in the construction process should ensure the integrity and stability of the surrounding rock around the tunnel, try toavoid damage and disturbance to the surrounding rock.At the same time within a certain range, you canincrease the thickness of the lining of the tunnelto reduce the seismic response of the tunnelstructure.Also in the tunnel structure to ensure adequate strength of the premise, as far as possible to reduce the elastic modulus of the lining so that it can effectively dissipate seismic energy during an earthquake.But if too poor rock conditions, by varying the elastic modulus and the thickness of the lining of the tunnel lining can not achieve the purpose of the tunnel seismic, you need to set the damping layer in the tunnel structure. Shock absorption layer is a very effective damping measures can force uniform cross-section, is conducive to the common crosssection of the force. With the increase of the thickness of the damping layer, tunnel deformation and inertial forces will increase, but reduce the stress response of tunnel lining has a significant effect, so to select the appropriate thickness of the damping layer as needed. Damping layer elastic modulus is smaller, the better the damping effect of the tunnel, so to ensure the stability of tunnel structure under the premise, as far as possible the use of small elastic modulus damping material. The traditional way is damping layer is disposed between the surrounding rock and initial support damping layer arrangement, generally suitable for large seismic intensity earthquakes, but the drawback is the construction more complicated and costly. In between initial support and secondary lining layer damping arrangement for weak seismic intensity earthquakes, and the construction more convenient, low cost, it is an ideal way.