Disaster Mechanism And Risk Assessment Of High Filled Embankment

With the development of mountain transportation, high filled embankment will further improve in the height and quantity. For a long time, due to the complexity of the design and construction, usually, the embankment disasters have occurred. Meanwhile, the risk of high filled embankment problem is widespread. Therefore, it is necessary for the systemic research on the disaster mechanism and risk problem In this paper, studies the disaster mechanism and risk assesstment theory.(1) Based on the collection of existing literature and the disaster investigation, summarize and analyze the high filled embankment type and defines four types of embankment failure: foundation landslide, subgrade slump, roadbed subsidence and roadbed crack. Foundation landslide is controlled by the ground conditions. Subgrade slump is contolled by the embankment strength. Roadbed subsidence and roadbed crack are controlled by the embankment strength and ground conditions.(2) From the deformation and strength characteristics to analyze the mechanism of settlement and instability. settlement is the result of pore volume change. Instability is the result yield stress. Changes in stress field, temperature field and wet field are the essential reason about the filled embankement disaster.(3) Using the finite element analysis software to analyze the effect of ground conditions, surface conditions, filling conditions and water. The main effect factors are the ground conditions, the degree of compaction and the water. The largest settlement are located at the maximum thickness. The largest horizontal displacements are located at the top of the outside, it presents the "retraction" phenomenon. The uneven settlement controlled by the filling thickness and the thickness of compressible soil. Circular slide is the main form of the unstable sliding.(4) Analyze the disaster risk and pointed that the instability risk is the main risk and the mechanical parameters is the main risk factor. Based on the reliability theory, established instability risk assessment model and taked the failure probability as evaluation index. Moreover, analyze the high filled embankment risk criteria and give the recommended value.