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Abstract To study the dynamic response of homogeneous slopes supported by lattice beams under earthquake，a small slopes model made of silica gel on shaking table was designed at the geometric scale of 1∶15. Under the same sinusoidal loading，the range of the strains at the same measuring point on the lattice beam is found to be largely unchanged before the failure and the strains varied sinusoidal accordingly. But in the stage of failure，the dynamic strains vary irregularly and reach very large values finally in the destruction phase. Additionally，the stress level of the horizontal lattice beam is the same as that of the vertical lattice beam under the same seismic excitations. For the horizontal lattice beams，the strains at the middle of the beams are larger than those at two ends of the beams. And for the vertical beams，the strains from the top to the bottom exhibit a feature of larger- smaller-larger-smaller variation，indicating that the slope deformation along the vertical beams are restrained by the anchors. When the frequency of the sinusoidal loading is the same，the dynamic strains on the lattice beams increase with the increasing of the seismic acceleration. When the input acceleration is the same，the measured strains are larger at low frequency cases than those at high frequency ones. The reason is that the input low frequency is close to the natural frequency of the model and thus the dynamic responses in low frequency conditions are stronger. The results demonstrate that the silicone slope model is suitable for studying the dynamic response of the slope with supporting structure. The model can be used repeatedly and greatly reduces the cost of test.
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Received: 14 April 2014
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2015, Vol. 34 
