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Abstract Large-scale shaking table experiment was carried out to study the dynamic response of the front slope of tunnel entrance with weak layer has，and general conclusions were obtained through analyzing the acceleration and failure modes of front slope of tunnel entrance and tunnel lining under the horizontal and vertical excitation. The results showed that the front slope had an obvious acceleration magnified effect under the horizontal excitation and the weak layer produced a significant impact on the dynamic response of the front slope under vertical excitation；The peak acceleration of the tunnel lining at the entrance was larger than that far from the slope surface，at the entrance the maximum peak acceleration occured in the vault while that minimum occured in the invert，the forced state of the lining was complicated；With vertical acceleration excitation，the overlying soil model of the weak intercalation loosed，the soil at the toe of slope squeezed and fall-block，however the slope remained stable overall；Under the action of horizontal excitation，the soil at the toe of the front slope crushed first，and then the slope surface location along weak intercalation cracked，the overlying soil layer along weak intercalation slided，at last large-scale dilapidation and fall occured；Under the vertical and horizontal vibration force，the maximum strain amplitude occured in the 45°of the lining，the fortified length of tunnel portal section is 25 m. These conclusions can be reference for design，construction and study on the tunnel seismic study.
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2015, Vol. 34 
