下伏煤系地层高填方路基边坡致灾机理及其处治技术

Disaster-causing Mechanism and Treatment Technology of High Fill Embankment Slope in Coal Measure Strata

煤系地层高填方路基边坡遇水易软化、崩解,透水性差,易产生滑坡病害。设置抗滑桩费用高,且设置抗滑桩后,滑动面以上的滑坡体仍然存在,滑坡风险无法完全解除。针对山区煤系地层高填方路基边坡病害时有发生的现状,此文以福建省内某山区典型路段为研究对象,从地形地貌、地层因素、水文地质条件、填方土成分等方面对煤系地层填方路基致灾成因进行了分析。连续降雨、水沿裂缝下渗是煤系地层边坡失稳的关键因素,填土层透水性差抬高地下水位会加速滑坡的形成,加剧致灾程度。基于此,提出了一种既满足稳定性要求,又可大幅降低造价的处治方案。并结合数值模拟方法对其稳定性进行了验证,对其工程造价、适用范围作了评价。

The slope of coal measure stratum high fill subgrade is easy to soften and disintegrate when encountering water,with poor permeability and easy to produce landslide disease.The cost of setting anti-slide pile is high,and after setting anti-slide pile,the landslide above the sliding surface still exists,and the landslide risk cannot be completely removed.In view of the current situation of filling roadbed diseases in coal measure strata in China,this paper takes a typical road section in a mountainous area in Fujian province as the research object,and analyzes the disaster causing factors from the aspects of landform,stratum factors,hydrogeological conditions,filling soil composition,etc.Continuous rainfall and water infiltration along cracks are the key factors of slope instability.The poor permeability of filling soil layer will accelerate the formation of landslide and aggravate the disaster.Based on this,a kind of management scheme which can meet the requirements of stability and greatly reduce the cost is put forward.The stability was verified by numerical simulation.The project cost and application range are evaluated.