【摘要】 在边坡工程分析中发现很多在地震作用下发生滑坡破坏的边坡当中有相当部分反倾层状结构的边坡。说明反倾边坡尽管结构相对稳定,但是由于内部含有软弱夹层同样有可能会降低边坡的整体稳定性。通过FLAC3D有限差分软件,对含不同角度和厚度软弱夹层的反倾岩质边坡在不同频率和振幅地震波作用下动力响应特性进行了研究。研究发现随着软弱夹层厚度增大,加速度放大系数并不是线性的减小,而是激励响应越弱,软弱夹层对波的能量削弱作用越大;随软弱夹层反倾角度的增大,边坡动力响应的变化规律是先增大,然后减弱,这和普遍认为的随着反倾角度增大,动力响应减弱的规律有所不同。进一步验证了地震波振幅和频率的变化对含反倾弱层边坡动力响应的影响规律。更多还原

【Abstract】 More and more landslides were observed to occur in the slopes with counter-tilt weak intercalation layers under seismic loads in field study,after W enchuan earthquake,in 2008. It is noted that the weak intercalation layer in the slope interior will lead to the decrease of the slope stability though the structure of the slope with counter-tilt weak intercalation layers are relatively stable. U sing the finite difference software FLAC-3D,this research mainly focused on the simulation of the dynamic response variation of rock slopes with weak intercalation layers of different inclination angles and thicknesses under the sinewave excitations with different frequencies and amplitudes. The simulation results showthat: with the increasing weak intercalation thickness,the amplification coefficient for PGA is not decreased linearly,and is weakened more obviously when the energy of the excitation is smaller. The intensity of the dynamic response of the rock slope is strengthened firstly,then weakened soon with the increase of the inclination angles of the intercalation,which is a little different from the universal law: the dynamic response is weakened with the increasing dip angle of the counter-tilt weak intercalation. The effect of the variation of the frequency or amplitude on the dynamic response of the slope is proved.更多还原