摘要
基于悬臂梁理论和运用极限平衡法研究反倾层状岩质边坡变形破坏是一种既注重变形过程又注重力学分析的可行方法。在国内外研究现状基础上,研究悬臂梁极限平衡分析模型。首先通过野外现象的观测,提出能对反倾层状边坡变形几何空间条件进行分区的"基准面"的概念,再利用"基准面"分析岩层分区破坏模式的力学机制,认为破坏面的形成机制是弯曲拉裂和压缩剪切的共同作用结果,对悬臂梁极限平衡分析模型中的各参数确定给出假设或理论分析,建立了计算模型。以重庆市巫溪县中梁水库硝洞槽-郑家大沟库段反倾岸坡为例,在边坡变形破坏模式识别基础上,应用悬臂梁极限平衡模型理论分析实例,验证该模型的合理性,同时也给出反倾层状边坡悬臂梁极限平衡模型计算步骤,用数值模拟方法验证该分析模型的正确性。模型计算结果表明,破坏区大体分为滑移区、倾倒区和倾倒变形影响区,破坏区大小由坡角、岩层倾角、坡高共同决定,当三者关系(见式(13))大于0时,才存在破坏区,才有可能发生变形破坏。研究成果对反倾层状岩质边坡稳定性评价与防治具有理论指导意义和应用价值。
It is a feasible method to study the deformation and failure of anti-dip layered rock slopes by using limit equilibrium method based on cantilever beam theory, which not only pay attention to deformation process, but also focus on the mechanics analysis. Based on the research status at home and abroad, this paper launched the research of cantilever beam limit equilibrium analysis model. Firstly, the concept of "reference surface" was raised through field phenomenon observation, by which the deformation geometric space conditions of the anti-dip layered slope can be partitioned; therefore the mechanism analysis of rock layer failure pattern could be done according to the different situations of partitions; and the conclusion was made that the formation mechanism of the failure surface is the combined effect of both curved tension and compression shear. On this basis, the hypothesis or the theoretical analysis of the various parameters in the cantilever beam limit equilibrium analysis model was given; and the calculation model was established. Finally, taking Zhongliang reservoir Xiaodongcao-Zhengjiadagou segment anti-dip bank slope in Wuxi County, Chongqing for example, based on the recognition of slope deformation and failure pattern, the theory of cantilever beam limit equilibrium model was used in this example, and the rationality of the model was verified. At the same time, the calculation steps were given; and the correctness of the analytical model was verified by numerical simulation method. Model results show that the damage zone can be divided into slip area, toppling area and toppling influenced zone; damage zone size is determined by slope angle, strata inclination and slope height; and damage zone only exists when the three relations (formula (13)) is greater than zero that deformation and failure could occur. The research results have theoretical significance and application value to the stability evaluation and prevention of anti-dip layered rock slopes.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2014年第S1期15-28,共14页
Rock and Soil Mechanics
基金
国家重点基础研究发展计划(973项目)资助(No.2011CB710605)
教育部新世纪"优秀人才支持计划"资助(No.NCET-07-0775)
关键词
反倾层状岩质边坡
悬臂梁极限平衡模型
破坏面
变形破坏特征
anti-dip layered rock slopes
cantilever beam limit equilibrium model
failure surface
distortion and failure character
