Bridge Vulnerability Assessment Of Debris Flow Disaster On Duwen Highway

As the economic carrier,highway is an important pillar of regional economic development.With the rapid development of China's social economy,especially the country's western development strategy has entered the stage of full implementation,the highway planning and construction in the western mountainous areas has also entered a stage of rapid development.The Duwen Highway is a fast-track between Dujiangyan and Wenchuan,and has important economic and military strategic positions.In the “5.12” Wenchuan earthquake,the road was seriously affected and almost all the bridges along the line were damaged or collapsed.After the earthquake,due to the severe damage to the regional geological environment,and the deep valleys along the highway,the terrain is steep and the terrain is complex,causing frequent geological disasters such as mudslides along the highway,causing great damage to the highway bridges and seriously restricting the local economy.Development and transportation operations,post-disaster reconstruction and other work.Therefore,it is necessary to comprehensively grasp the current situation of highway bridges,consider and analyze the influencing factors of damaged and damaged,and evaluate and analyze the vulnerability in a timely and effective manner,so as to provide certain decision-making reference for local road traffic construction and disaster prevention and mitigation planning.The current research is mainly about highway Bridges vulnerability assessment for engineering activities and the earthquake effect,from the aspects of engineering structures,mechanical parameters,such as Bridges of vulnerability evaluation analysis,without too much consideration the quake zone along the highway geological disaster effect on bridge damage,lack of highway bridge under the influence of the debris flow disaster vulnerability assessment research.Based on the previous research results,this paper comprehensively considers the distribution factors of geological disasters along the highway in the study area,comprehensively constructs the vulnerability evaluation index system of highway debris flow disaster,and selects the risk of debris flow as the key evaluation index,and adopts the gray system evaluation model.Vulnerability evaluation and analysis of 9 bridges along the highway.The main results of the paper are as follows:1)Analyze and summarize the related research on bridge vulnerability assessment at home and abroad,consider the impact of debris flow disasters on bridge damage in the earthquake zone,and construct a set of vulnerability assessment index system for highway debris flow disasters.By comparing with relevant research data and field investigations,it shows that the evaluation results are in good agreement,so it also reflects the good applicability and effectiveness of the index system,which provides a reference for other similar regional studies.2)The evaluation results show that the vulnerability of the bridge in the study area is generally high,and 55% of the bridges are moderately vulnerable.Among them,the three bridges such as the Duxiufeng Bridge are highly vulnerable,and the bridges with low vulnerability are only A bridge of Yingxiuwan Hydropower Station.Through further analysis and discussion,it is found that the vulnerability of the bridge in the study area is obviously affected by the debris flow disaster along the highway.Based on this,the relevant prevention and treatment countermeasures are proposed.