By consulting domestic seismic study on tunnel entrance

large scaled shaking table model tests of the entrance on homogeneous upward slope

slope with weak intercalation and strengthened slope were carried out in laboratory. General conclusions were obtained through analyzing the failure modes of the upward slopes. Under the earthquake

tension cracks appeared first at the shoulder of the slope

with the excitation acceleration increasing

soil at the shoulder started to dump and collapse; when introducing the weak intercalation

the soil at the toe of slope was squeezed broken firstly

tension cracks of the surface appeared at the weak interlayer positions

overlying soil sliding along the weak interlayer and leads to large-scaled soil collapse; the strengthened slope remained stable under the action of the force

only caused partial soil failure; minor axial cracks appeared at top. By analyzing the tunnel structure failure

the test results show that the fracture distribution on the A and B linings of tunnel portal are more complex than that on C and D linings; the total length can be taken as the earthquake affect length

which corresponds to 40m at the actual project. Affected by the weak interlayer

the fracture of the lining parts crossed the weak interlayer are more complex than others; the slope reinforcement can improve the stress state of both the slope and portal structure. These conclusions can be for reference in design and construction of tunnel under earth quake.