【摘要】 基于一维波动模型和分数导数粘弹性本构关系,分析了在竖直方向上传播的剪切地震波作用下,基岩上分数导数粘弹性模型描述的场地土的横向振动问题,用直接刚度矩阵法求得了场地土的地震放大效应系数,并用数值算例讨论了相关参量对分数导数粘弹性场地土地震放大效应系数的影响。研究结果表明:在简谐剪切地震波作用下,分数导数粘弹性场地土存在共振现象;分数导数的阶数、模型参数和基岩与上覆场地土层底部之间的阻抗比对场地土的地震放大效应系数有较大的影响。更多还原

【Abstract】 On a bedrock subjected to the steady state and vertically propagating shear seismic waves,the lateral vibration of the ground soil is investigated with one-dimensiona1 wave model and fractional derivative viscoelastic constitutive,the amplification factor is obtained based on the method of direct stiffness matrix,the influences of related parameters on the seismic amplification factor is analyzed by a numerical example.The result indicates that the ground soil described by fractional derivative viscoelastic model has a resonance under the excitation of steady state shear seismic waves,and the order of fractional derivative,model parameter and impedance ratio have big effects on the seismic amplification factor of ground soil.更多还原