地震激励下某土岩二元结构边坡锚索轴力响应探析

Analysis of anchor cable axial force response of a soil rock dual structure slope under earthquake excitation

以某预应力锚索-框架支护土岩二元结构边坡为依托,借助FLAC3D5.0软件进行地震作用数值模拟,对不同工况的锚索轴力响应进行分析。结果表明,边坡在地震作用下的稳定性与锚索轴力变化过程正相关;地震波强度较小时,由于边坡的自稳作用,在地震惯性力作用下,锚索不但无法发挥抑制作用,反而会出现预应力损失;地震波强度较大时,边坡滑裂趋势位置处的锚索瞬间响应,轴力迅速增大,从而抑制边坡滑移破坏;岩石与土体材料的刚度和阻尼在土体与岩石相交面位置处发生突变,可以判定交界处相对较薄弱或可能为剪出口。

Based on a prestressed anchor cable-frame-supported soil-rock dual structure slope,numerical simulation of seismic action is carried out with the help of FLAC3D5.0 software,and axial force response of anchor cable under different working conditions is analyzed.The results show that the stability of slope under earthquake is positively correlated with the change process of anchor cable axial force.When the seismic wave intensity is small,due to the self-stability of the slope,the anchor cable can not play a restraining role under the action of seismic inertia force,but will appear the loss of prestress.When the seismic wave intensity is large,the anchor cable at the slope sliding trend responds instantly,and the axial force increases rapidly,which inhibits the slope sliding failure.The stiffness and damping of rock and soil material change at the intersection of soil and rock,which can be judged to be relatively weak or shear outlet.