地震荷载作用下坡体正交型上跨隧道衬砌应变响应研究OA

In order to investigate the dynamic response characteristics of the inner and outer linings of an orthogonally overcrossing tunnel under different seismic wave intensities,a shaking table model test with a scale ratio of 1:100 was conducted.Different Kobe waves(0.1g,0.2g and 0.4g)were applied,and peak analysis and time-history analysis were performed on the strain response of the lining structure in the tunnel model.The results showed that:(1)an increase in seismic wave intensity caused the strain distribution in the inner lining to change from a"quasi-rectangular"pattern to a"quasi-triangular"pattern,with notable strain concentrations occurring at the arch crown and the arch feet on both sides.Meanwhile,the strain distribution in the outer lining gradually evolved from a"quasi-circular"pattern to a"butterfly-shaped"pattern,and the strain response at the arch crown and the invert was particularly prominent.(2)The measuring points of the inner and outer linings exhibited different tension-compression states under seismic loading.The arch crown and the left arch foot of the overcrossing tunnel mainly experienced tensile strain,whereas the left arch waist was in compression.In contrast,the inner and outer linings at the invert,the right arch waist,and the right arch foot exhibited tension-compression or compression-tension states,indicating a tendency toward non-uniform deformation and a higher damage risk of the right lining under seismic loading.(3)The damping effect of the inner and outer lining structures of the overcrossing tunnel resulted in a pronounced difference in the timing of the tension-compression transition,and the peak strain of the outer lining occurred earlier than that of the inner lining.