某高速公路黄土边坡稳定性研究

Study on the Stability of Loess Slope of a Highway

随着我国西部大开发和一带一路的建设,广泛分布有黄土的西北地区基础设施得到迅速发展。为了研究高速公路黄土高边坡的稳定性,采用矢量和法,借助于ANASUS有限元软件,对A高速公路某高路堑边坡的稳定性从静力和动力两个方面进行数值模拟研究。成果表明,边坡各级台阶的边坡坡脚位置出现应力集中现象,在边坡整体的坡脚位置出现非常明显的应力集中现象,这些在坡脚形成的剪应力增高带正是引起边坡剪切破坏的主要原因;加速度为0.1 g的地震作用下,坡顶加速度响应峰值可达0.16 g,可见,动力作用下边坡坡顶位置的稳定性最差;同时,数值模拟结果表明,在动力和静力条件下该边坡均处于稳定状态,对其坡顶、坡面和坡脚3个位置处的累积位移值研究表明,加速度为0.1 g的地震作用下,坡顶位置会累计产生高达的沿坡面向下12 cm的位移。

With the development of the western region and the construction of the whole area along the western part of China,the infrastructures with extensive distribution of loess in the northwest have developed rapidly.In order to study the stability of highway loess high slope,this paper uses vector method and ANASUS finite element software to simulate the stability of a highway cutting slope from static and dynamic aspects.The results show that:Firstly,stress concentration occurs at the foot of the slope at all levels of the slope steps,and very obvious stress concentration occurs at the foot of the slope as a whole.These shear stress increasing zones formed at the foot of the slope are the main causes of the shear failure of the slope.Secondly,the peak value of slope top acceleration response can reach 0.16g under earthquake with acceleration of 0.1g,which shows that the stability of slope top position under dynamic action is the worst.Thirdly,the numerical simulation results show that the slope is in a stable state under both dynamic and static conditions.The cumulative displacement values at the top,surface and foot of the slope are studied.The results show that under the seismic action of 0.1g acceleration,the top position of the slope will accumulate displacement up to 12 cm downward along the slope.