双层反翘滑坡渐进破坏力学模型及失稳判据研究

以襄十高速公路韩家垭滑坡为背景，对滑坡的“双层蠕滑-反翘变形-弯曲折断一坡体滑移”的渐进破坏机理进行了深入分析，通过将滑坡前缘陡倾顺层结构变粒岩层概化为滑床部位锁固而其余边界自由的多层矩形薄板结构，滑坡的反翘弯曲破坏问题视为在纵、横向荷载作用下，多层矩形薄板的屈曲-弯曲变形以及变形到一定程度时岩层板的断裂破坏问题，基于Rayleigh-Ritz能量变分原理，建立了滑坡的渐进破坏力学模型，提出了滑坡的稳定性判据及滑坡整体启动滑动面抗剪强度阀值。最后，根据模型试验的加载参数及渐进破坏力学模型对滑坡的稳定性及抗剪强度阀值进行了计算分析，其结果与模型试验的测试结果相符，表明所建立的力学模型是合理可行的。

Study on Gradual Destruction Mechanical Model and Criterion of Instability of Landslide with Double Sliding Planes and Rock-layer Reverse

Taking the example of Hanjiaya landslide in Xiangshi Expressway,the gradual deformation and failure mechanism of "double plane creeping slide-rock-layer reverse deformation-bending break-slope sliding" of the landslide is analyzed in-depth.According to the behavior of the reverse layered rocks,pre-failure deformation of landslide can be described by bending of multilayered rectangular plates with one adjacent edge fixed and the other free under combined transverse and lateral loads,and the question of reverse rock-layer bending break can be viewed as buckling-bending and critical rupture of the plates.By means of Rayleigh-Ritz energy principle,the gradual destruction mechanical model of landslide is established and the instability criterion of landslide and the critical shear strength of the sliding plane when the whole landslide starts in motion are deduced.Finally,according to the loading criterion and the gradual destruction mechanical model of the laboratory model test,the stability of the landslide and the critical shear strength are calculated and analyzed.Comparing the deducted results of mechanical model with those of laboratory model test,the conclusion can be drawn that the model is reasonable and can qualitatively analyze the gradual destruction process of the landslide.