雨水浸润软化下路基土质边坡浅层稳定分析

发布时间：2018-02-11 03:40

本文关键词： 土质边坡浸润软化深度浅层稳定性破坏模式对数螺旋线　出处：《铁道学报》2017年04期 　论文类型：期刊论文

【摘要】：在雨水浸润软化引起边坡浅层失稳的"顺坡平面"和"顺坡折线"两种破坏模式基础上,明确边坡浅层溜坍呈现组合式"顺坡曲面"失稳模式;基于Mohr-Coulomb强度理论,建立雨水浸润软化土体达到破坏的判别方程,导出顺坡向滑动的主滑区滑体产生剩余下滑力对应的最小软化深度zcr,论证软化深度zw=zcr仅是产生浅层失稳破坏的必要条件,充分条件还须考虑上下缘滑体的力学作用;确定对数螺旋线滑体上下缘滑动面形态,提出满足上下缘滑体力矩平衡、中段主滑体静力平衡的土质边坡浅层稳定分析方法。分析表明:浅层边坡失稳的主滑区范围L2随zw呈双曲线衰减关系,在L2=0对应的最大浸润软化深度zf下,滑动面退化为具有对数螺旋线型特征的单一整体滑面破坏模式。
[Abstract]:On the basis of two failure modes of "downhill plane" and "downhill break line" caused by Rain Water's infiltration and softening, it is clear that the combined "downhill surface" failure mode is presented in the shallow collapse of slope, and based on Mohr-Coulomb strength theory, A discriminant equation for the failure of Rain Water soak-softening soil is established, and the minimum softening depth zcrs corresponding to the residual sliding force in the main sliding zone along the slope is derived. It is proved that the softening depth zw=zcr is only a necessary condition for the shallow instability failure. The sufficient conditions must also consider the mechanical action of the upper and lower edge slip body, determine the shape of the upper and lower edge sliding surface of the logarithmic spiral slip body, and propose that the upper and lower edge slip body should meet the torque balance of the upper and lower edge slip body. The method of shallow stability analysis of soil slope with static equilibrium of main sliding body in middle section shows that the main slip zone L _ 2 of shallow slope shows hyperbolic attenuation relationship with zw, and under the maximum infiltration softening depth zf corresponding to L _ 2N _ 0, the main slip zone of shallow slope is of hyperbolic attenuation. The sliding surface degenerates into a single global sliding surface failure mode with logarithmic helical characteristics.
【作者单位】：西南交通大学高速铁路线路工程教育部重点实验室;
【基金】：国家重点基础研究开发计划(973计划)(2013CB036204)
【分类号】：U416.16

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