Study On Anti-seismic Measures Of The Tunnel Hoods On High-speed Railway In Open Air

There will be a significant aerodynamic effect when the high-speed trains pass through the tunnel. In order to solve this problem, setting hood at tunnel entrance usually is one of the efficacious ways. Compared to the tunnel, the anti-seismic effect of the hood is much worse. Because the high-speed railway of our country develop very rapidly and most of our country is the earthquake region, therefore, the research on seismic characteristics and the anti-seismic measures of the tunnel hood has an important significant.This paper analyzed the seismic dynamic response of the side-strip and top combination opening hood, two-side-strip opening hood, two seam opening hood, side and top combination opening hood and no opening hood through the ABAQUS which is a finite element software. At the same time, four anti-seismic measures, seismic joints, concrete floor, combination of seismic joints and concrete floor and combination of seismic joints and reinforcement rods, were put forward. Then their anti-seismic effect were analyzed and evaluated. The main conclusion are as follows:(1) Under the effect of the earthquake wave, the order of the acceleration response of the various parts is:arch crown> arch shoulders and arch waists> arch foots and invested arch; the order of the acceleration response of the various hoods is:two-side-strip opening hood< side-strip and top combination opening hood< no opening hood< side and top combination opening hood< two seam opening hood; opening can increase the acceleration of it which closes to itself.(2) Under the effect of the earthquake wave, the order of the Mises stress response of the various parts is:arch waists> arch shoulders> arch foots> arch crown and invested arch(the Mises stress of the arch crown and arch foots of the two-side-strip opening hood are about the same); the order of the Mises stress response of the various hoods is:two-side-strip opening hood< no opening hood< side and top combination opening hood and two seam opening hood< side-strip and top combination opening hood; the changing extend of the Mises stress is wider closing to the opening.(3) Under the effect of the earthquake wave, the order of the max principal stress response of the various parts is:arch waists> arch crown> arch shoulders> arch foots> invested arch; the order of the max principal stress response of the various hoods is:no opening hood< two seam opening hood< side and top combination opening hood< two-side-strip opening hood< side-strip and top combination opening hood; opening can increase the max principal stress.(4) Seismic joints can increase the acceleration response of the various parts closing to hoods’ Seismic joints. But they can reduce the Mises stress and the max principal stress of the various parts. So seismic joints have a good anti-seismic effect.(5) Concrete floor can obviously increase the acceleration response of the various parts except the arch crown. And they can obviously increase the Mises stress and the max principal stress of the various parts closing to tunnel entrance, but their effect is opposite for the other parts. So concrete floor’s anti-seismic effect is not obvious.(6) Combination of seismic joints and concrete floor can obviously reduce the acceleration response, the Mises stress and the max principal stress. So combination of seismic joints and concrete floor’s anti-seismic effect is very obvious.(7) Combination of seismic joints and reinforcement rods can obviously increase the acceleration response of the various parts, and they also can increase the Mises stress and the max principal stress for most parts. So combination of seismic joints and reinforcement rods ’s anti-seismic effect is poor.