考虑反倾破坏面的高陡公路岩质边坡倾覆分析

Analysis of steep road rocky slope tipping considering anti-tip damage surface

当前针对高陡公路岩质边坡的岩柱倾覆分析中,通常假设以单一的弱面角从坡顶向坡底处开隙。但当岩体内部存在反倾破坏面时,单一的弱面角得到的结果无法反应真实的倾覆过程。为了准确分析高陡公路边坡倾覆趋势,本文提出反倾破坏中真实弱面角的搜索方法,基于极限平衡法对岩柱倾倒过程中的公路边坡进行稳定性分析,并使用离散元数值模拟对案例边坡进行验证。研究结果表明:1)弱面角和边坡高度的增加导致倾覆产生的位移显著,在35°弱面角和坡顶处均记录到最大位移;2)反倾斜破坏面角度的变化导致岩柱的中部区域和下部区域的破坏模式的不一致,当发生倾倒破坏的岩柱接近反倾弱平面时,其破坏方式由倾覆变为滑动。改进后的分析方法结合并优化了传统分析技术,可为含反倾破坏面的高陡公路岩质边坡倾覆机理及稳定性评估提供更为精确的分析方法。

In the current analysis of rock column overturning for high and steep road rock slopes,a single weak face angle is usually assumed to form the crack from the top to the bottom of the slope.However,when there is an anticlinal damage surface inside the rock mass,the results obtained from a single weak surface angle cannot reflect the real overturning process.In order to accurately analyze the overturning trend of high steep road slopes,this study proposes a search method for the true weak surface angle in anticlinal damage.Based on the limit equilibrium method,the stability analysis of the highway slope in the process of rock column tipping is carried out,and the case slope is verified using discrete element numerical simulation.The results show that:1)The increase of weak face angle and slope height leads to significant displacements from overturning,and the maximum displacements are recorded at 35°weak face angle and slope top.2)The change of the angle of the anticlinal damage plane leads to the inconsistency of the damage pattern in the middle region and the lower region of the rock column,and the damage pattern changes from overturning to sliding when the rock column with overturning damage is close to the anticlinal weak plane.The improved analysis method combines and optimizes the traditional analysis techniques,which can provide a more accurate analysis method for the overturning mechanism and stability assessment of high steep highway rocky slopes with anticlinal damage plane.