高速公路路堑高边坡施工安全风险控制研究

Research on risk control of construction safety in high cut slope of expressway

为避免边坡施工过程中发生失稳破坏,以广东省仁化至博罗高速公路K443+260~K443+585路堑边坡为研究对象,通过现场调查和资料收集,分析造成边坡局部滑塌的原因。运用有限元强度折减法,研究边坡进一步施工的安全稳定性和变形规律,为控制边坡安全风险提供依据。研究表明:边坡岩体裂隙发育,遇水软化,强度低是造成边坡局部滑塌的主要原因;边坡开挖过程中如果不及时支护,边坡的安全系数将下降约10%,不利于边坡的稳定。当遵循开挖一级支护一级原则时,边坡安全性可得到保证;高速公路路堑高边坡施工时采取合理安排施工工序、做好防排水措施、加强施工监控等安全风险控制措施十分必要。

To avoid the phenomenon of partial slump in the construction process of slope,taking the cut slope at K443 ＋ 260- K443 ＋ 585 of the expressway from Renhua to Boluo in Guangdong province as the research object,the reasons causing the partial slump of slope were analyzed through field survey and data investigation. The safety stability and deformation law of slope for the further construction were studied by using the finite element strength reduction method,so as to provide the basis for controlling the safety risk of slope. The results showed that the fissure development,water-weakening and low strength of slope rock body are the main reasons causing the partial slump of slope. During the excavation process of slope,if the support measures have not been taken timely,the safety coefficient of slope will decrease by 10%,which is bad for the stability of slope. The safety of slope can be guaranteed by adopting the principle of excavation followed by support at once. It is necessary to apply the safety risk control measures during the construction of high cut slope in expressway,such as arranging the construction procedure reasonably,making well the waterproof and drainage measures,and strengthening the construction monitoring.