More and more shield tunnels will crossing each other with very short distance with the rapid development of urban rail transit construction in China. There are four tunnels crossing each other between Hongshan Square Station and Zhongnan Road Station
which are the second line and the fourth line of Wuhan rail transit. The complicated multi-tunnels were simplified as four parallel tunnels and four perpendicular tunnels with different distances according to their practical characters. Three dimensional calculation models are established and their seismic responses are analyzed
in which the following aspects are considered: amplitudes seismic waves
tunnel net distance
tunnel space position
the difference of segment stiffness and the reinforced layer between tunnels. And then
their seismic capabilities are evaluated through two aspects: structure deformation and component internal forces. The analytical results show
(1) The net distances between tunnels have little influence on tunnel seismic responses; (2) The seismic capabilities of four perpendicular tunnels is superior to that of four parallel tunnels. (3) Adjacent overlapping multi-tunnels have good seismic capabilities and can satisfy seismic requirement. The research results can provide preliminary design for relevant practical engineering in future.