剪胀角对分层边坡稳定性的影响

利用有限元软件ABAQUS,采用强度折减法,对不同层数、不同材料、不同高度的分层边坡剪胀角进行折减,分析了剪胀角对分层边坡稳定性的影响。结果表明,对分层边坡,任意土层的剪胀角进行折减时,安全系数Fs随着剪胀角的增加而增大,增大的幅度逐渐减小,其变化规律不受土层材料、高度、层数的影响。与边坡整体的剪胀性相比,单层土的剪胀性对Fs的影响要小,且边坡上层土层的剪胀性对边坡稳定性的影响较大。随着剪胀角的增大,边坡位移趋势越加明显,且塑性区的范围逐渐扩大,滑弧半径增大,安全系数随之增大。在实际工程中,宜对分层边坡整体的剪胀角进行折减并慎重取值。

Effects of Soil Dilatancy Angle on the Stability of Stratified Slope

The soil dilatancy angles of the stratified slopes with different layers, different materials, and different heights were reduced to analyze the effects of soil dilatancy angle on the stability of stratified slope using the strength reduction method and finite element software ABAQUS. The results showed that when the soil dilatancy angle decreased for any soil layer, the safety factor Fs increased with the increasing of dilatancy angle while the increment decreased gradually and the safety factor was not affected by the soil material, height, number of layers. The dilatancy angle of a single soil layer had lower effects on the safety factor Fs compared with the overall slope, and the dilatancy angle of the upper soil layer of the slope had higher effects on the stability of the stratified slope. With the increasing of dilatancy angle, the displacement trend of the slope became obvious with an expanding range of plastic zone and an increasing sliding arc radius and safety factor . In practical engineering, it is better to reduce the soil dilatancy angle of the slope to a carefully selected value .