开挖对岩质边坡稳定性影响的数值模拟

Numerical Simulation of the Impact of Excavation on Stability of Rock Slope

以西部某露天矿开挖形成的岩质边坡为工程背景,运用数值模拟软件FLAC3D对开挖过程中岩质边坡体开挖方向上的应力演化和变形规律进行了数值模拟研究。研究结果表明:由于露天开挖形成的岩质边坡工程体在开挖过程中其内的压应力将发生明显的减小,自上而下呈"W"型分布,且在边坡体的中部将形成明显的拉应力区,这将是岩质边坡体发生失稳的原因之一;开挖过程也将导致岩质边坡内各岩层产生明显的膨胀变形,且埋深越大时产生的膨胀变形越大;由于复杂应力演化条件作用,岩质边坡坡脚处产生的沿开挖方向的变形最大。

Taking rock slope formed in the process of excavation in the west as project background,the numerical simulation on the law of stress evolution and deformation on the excavating direction of rock slope was carried out by numerical simulation software-FLAC3D.The results showed that the stress of rock slope formed by excavation was significantly reduced in the process of open excavation,showing like ＂W＂ from up to down,and tensile stress zone was formed in the middle of model,which was one of key reasons that caused rock slope failure.Significant expansion deformation of rock slope appeared in the process of excavation,and it was bigger as the increase of depth.The deformation along the direction of excavation at foot of the rock slope was maximum because of the rule of complicated stress evolution.