不同水位骤降速度下的混合堤防边坡稳定性分析

Stability analysis of mixed dike slope under different water sag speeds

黑龙江流域广泛存在由砂土和黏性土混合填筑而成的混合堤防。本文以典型混合堤防为研究对象,通过数值计算的方法研究洪水浸泡下不同水位骤降速度下混合堤防边坡的渗流稳定性和抗滑稳定性。研究表明:水位骤降对迎水边坡的渗流稳定性和抗滑稳定性均不利。边坡抗滑稳定性系数先快速下降到最小值后缓慢增大。不同降速下,降速越大,堤防边坡稳定性越差。降速由0.05cm/s增大到0.10cm/s时抗滑稳定性系数降低较大,而降速达到0.15cm/s时降速对边坡稳定性影响较小。该研究为由堤防溃堤而引起的水位骤降对其他堤防段边坡稳定性带来的影响提供了参考。

There are many mixed embankments made of sand and clay in Heilongjiang River Valley, This paper takes typical hybrid dike as the research object, The seepage stability and anti sliding stability of the mixed dike slope under the condition that the water level drops at different speed by numerical calculation, The researche shows that the stability of seepage flow and anti sliding of the upstream slope is unfavorable when the water level drops, The anti sliding stability coefficient of the slope decreases rapidly to the minimum and then increases slowly, The higher the rate of descent, the worse the stability of the embankment slope. The anti-sliding stability coefficient decreased significantly when the deceleration increased from 0.05 cm/s to 0. 10 cm/s, while the deceleration had little impact on the stability of the slope when the deceleration reached 0.15 cm/s. This study provides a reference for the effect of water level collapse on the stability of other embankments.