坡趾开挖试验及PIV分析下的矿山边坡桩布设效果研究

Researchon the Effect of Mine Slope Pile Layout Based on Slope Toe Excavation Test and PIV Analysis

矿山露天挖掘中,坡趾开挖过程增加了矿山边坡崩塌滑落的可能性。为了提高挖掘工作效率和安全性,现在较多矿山有效地布设边坡桩从而降低坡趾开挖引起的崩塌风险。本研究中,首先对坡趾开挖的边坡实施了1G模型试验,探讨了边坡的布设效果和桩对边坡坍塌的影响,并进一步采用粒子图像分析法(PIV)研究了边坡桩的加固效果和边坡破坏基本特征。研究结果表明:(1)桩的横向排布和竖向排布对坡趾开挖宽度没有显著影响,而竖向排布时从桩发生的剪断顺序可以预测边坡坍塌;(2)研究中观察到了桩数增加带来的加固效果,为了防止边坡桩断裂后土中应力分布复杂化,需选择合适位置进行桩基布设。本研究成果可为露天矿山边坡今后安全作业以及滑坡等灾害的防治起到重要作用。

In open-pit mine excavation,the excavation process of slope toe increases the possibility of collapsing and sliding of the mine slope.In order to improve the efficiency and safety of excavation,it is necessary to effectively arrange slope piles to prevent collapse caused by excavation of slope toe.In this study,the 1G model experiment has been carried out on the excavated slope toe,the layout effect of the slope and the influence of the pile on the slope collapse were discussed,and the particle image analysis method(PIV)was further used to study the reinforcement effect of slope piles and the basic characteristics of slope failure.The research results show that:(1)The horizontal and vertical arrangement of piles have no significant influence on the excavation width of the slope toe,and the shearing sequence of the piles in the vertical arrangement can predict the slope collapse;(2)the reinforcement effect brought by the increase in the number of piles has been observed in the study.In order to prevent the stress distribution in the soil from being complicated after the slope pile breaks,it is necessary to select a suitable location for the pile foundation layout.The results of this research can play an important role in the prevention and control of landslides and other disasters on open-pit mine slopes.