Dynamic Response Analysis for Intersection of Transverse Traffic Tubes and Main Tunnel in a Highly Seismic Region

The intersection of the transverse traffic tube and main tunnel is the weak link in the tunnel, as its structural forms are changed greatly and stiffness is discontinuous, so it does not help resist the seismic action. Based on the soil-structure interaction model and the use of visco-elastic boundary conditions and of time history analysis method, this paper, in combination with the Menglian tunnel engineering on the Bao-Teng Highway in Yunnan, has made a research of seismic dynamic response in the aforesaid intersection by analyzing its seismic dynamic characteristics and stability upon acquiring its displacement, stress, acceleration of dynamic response and distribution characteristics, and then put forth some disposal measures by seismic reinforcement, which can serve as reference to seism-reducing design of the weak link in the tunnel as well as other similar projects in a highly seismic region.