反倾岩质边坡多级破坏边界折断深度计算模型

A calculation model of boundary breaking depth for multilevel failure of anti-dip rock slopes

目前对边坡多级破坏折断深度及演化过程的研究相对较少,针对这类问题,在已有破坏边界模型的基础上采用悬臂梁极限平衡理论,对边坡多级破坏边界折断深度进行理论推导,建立多级破坏边界折断深度的计算模型,并通过大型离心模拟试验及工程实例对模型的可靠性和适用性进行验证。结果表明:离心模拟试验展现的多级破坏边界演化过程与提出的岩质边坡破坏边界一致,经计算二级破坏边界的折断深度为215.35 mm,三级破坏边界的折断深度为87.39 mm,模型计算结果与离心机试验结果相吻合,验证了所建立模型的可靠性;利用计算模型对云南省澜沧江左岸一处反倾岩质边坡多级折断深度进行计算,其二级破坏边界折断深度为8.06 m,三级破坏边界折断深度为2.34 m,经现场测量其二级、三级破坏边界折断深度分别为6~10 m和0.5~2 m,计算结果与边坡实际相符。研究成果对反倾层状岩质边坡稳定性及破坏机制的分析具有理论指导意义。

At present,there are relatively few studies on the fracture depth and evolution process of multi-level failure of slopes.In order to solve such problems,the limit equilibrium theory of the cantilever beam is used on the basis of the existing failure boundary model to deduce the fracture depth of the multi-level failure boundary of slopes,a calculation model of the fracture depth of the multi-level failure boundary is established,and the reliability and applicability of the model are verified through large-scale centrifugal simulation tests and engineering examples.The results show that the evolution process of the multi-level failure boundary shown by the centrifugal simulation test is consistent with the proposed calculation model.According to calculation results by the proposed model,the fracture depth of the secondary failure boundary is 215.35 mm,and the fracture depth of the third-level failure boundary is 87.39 mm,which are consistent with the centrifuge test results.Calculation results of an anti-dip rock slope on the left bank of the Lancang River in Yunnan Province buy using the calculation model show that the fracture depth of the first-level failure boundary is 8.06 m and the third-level failure boundary is 2.34 m.The field measurements of the second-level and third-level failure boundaries are 6–10 m and 0.5–2 m respectively.The calculated results are consistent with the actual measuring values.The research results have theoretical guiding significance for the analysis of the stability and failure mechanism of the anti-dip layered rock slope.