济南市砚池山高边坡优势面控稳分析

砚池山位于济南市区东部,由于长期采矿,山体局部已经变形且曾发生过崩塌。运用优势面理论对砚池山高边坡控稳机制进行分析。该边坡发育4组优势面,优势面组合形成 3 种优势分离体;优势面及优势分离体控制着边坡稳定性,形成5种破坏机制;当达到临界条件即在强降水或连续降水等不利条件时,岩性参数进一步降低,塑性区就会扩大,坡顶竖向拉裂缝和填土与闪长岩岩体之间的接触面正好构成了一个潜在的整体滑动面。最后,运用有限元法对边坡稳定性进行定量分析,评价结果与优势面理论分析结果一致,结果表明,该边坡是不稳定的,应及时采取治理措施。

Analysis of Stability Controlled by Preferred Plane of Yanchishan High Slope in Jinan City

Yanchishan Hill is located in the east of Jinan city. Because of perennial mining, deformations and slumps have occurred locally within the hillside of Yanchishan. There are lots of factors influencing the stability of the western slope. The potential instability of slope poses damage to the developing district lying near the west of Yanchishan slope. This paper analyses the mechanism controlling the stability of the high slope of Yanchishan using the preferred plane theory. The analytical results indicate that there are 4 sets of preferred planes and 3 groups of preferred isolated bodies dictated by the preferred plane assembling. The slope stability is controlled by the preferred planes and preferred isolated bodies and 5 failure mechanisms is formed. Under the adverse conditions such as intense or prolonged precipitation, the strength of rock mass will decrease and the plastic area will extend. Vertical cracks at the top of slope and the interface between the dredger fill and dioritic rock mass constitute a potential slip surface. Finally, the slope stability is quantitatively evaluated by finite element method, and the evaluation results agree well with what the preferred plane method predicts. It is concluded that the Yanchishan slope is potentially unstable and corresponding treatment measures need to be carried out.