Risk Assessment For Impact Of High Slope Construction Of Freeway Reconstruction And Extension On Operation Security

The route of freeway which under the reconstruction and extension is relatively long, the topography and landform, geological conditions and present situation of old subgrade are all different. So construction along the slope may change the original supporting method, brings instability risk to the slope, then lead to traffic disruption and operation security accidents. In addition, high slope construction would seriously affect the vehicles on the existing highway, causing the risk of traffic accidents.Thus need us to make a reasonable plan about construction and traffic organization before the construction, to ensure the highway can operate smoothly and safety during the process of the high slope construction. Therefore, it is so important to establish a set of applicable operation security risk evaluation index system combined with the operation security features in high slope construction on freeway reconstruction and extension.At present, scholars at home and abroad study on operation security risk evaluation are mainly considered from the highway operating environment, although some already considered the factors of road conditions and high slope stability, but few people have thinking about the effect of the high slope reconstruction and expansion project on operation security.Therefore, in this paper, based on the construction" LiuNan "freeway reconstruction and extension project, combined with the method of site investigation, mathematic modeling and theory analysis, I have conducted in-depth research to the risk evaluation index system for operation security in high slope construction on freeway reconstruction and extension, and then I get the following main results:(1)Analyzed the characteristics of freeway expansion project construction on the high slop and their effects on operation security, identified the existence of risk sources, then determined the main influencing factor to the operation security during the process of high slop construction, and established risk evaluation index system for operation security in high slope construction on freeway reconstruction and extension.(2)Based on T-S fuzzy neural networks, built operation security risk prediction model in high slope construction on freeway reconstruction and extension, and established the risk grading criteria, to evaluate operation security accidents risk level.(3)Analyzed from two aspects: the vulnerability of hazard-bearing body and its value. Based on the Analytic Hierarchy Process and Fuzzy Mathematics theory, built the fuzzy synthetic evaluation model of operation security accident risk. At the same time, determined the hazard ratings divided standard, and using VB language to compile the operation security accident risk evaluation software, preliminary realizes intellectualization and rapidness to evaluate the operation security accident risk of high slope construction.(4)Divided the operation security risk into five grades, from two indexes (operation security risk and accident harm) to establish the risk evaluation index system for operation security in high slope construction on freeway reconstruction and extension, and do characterization to the risk.(5)With Xiaopingyang high slope construction on Liunan freeway reconstruction and extension project for case study, compared and evaluated the situation under different construction and traffic organization method. According to the evaluation results to determine the risk size and sources, and accordingly make the decision about risk management and control. The results verify the applicability and reliability of the evaluation method in this article.