The Risk Analysis On Construction Safety Of Maqu Yellow River Bridge

In the background of China’s “The Belt and Road” development strategy in new age,Transportation industries are developing rapidly in China.With a high-speed growth about the road net in the mid-west,in which cross river,rail,canyon bridge works are also increasing rapidly.There are many construction issues continue to arise,such as new technology,Span length,large dead weight,complex interface environment and other challenges.At the same time,the probability of safe accident during construction is being increased.There are many differences between the northwest area and southern area in China,for example,geographical environment,natural conditions,construction technology of bridge and safety management system.Therefore,the safety risk assessment of bridge construction in southern China is inapplicable to the northwest.It is certainly worth studying the safety risk assessment of specific environment.This will achieve greater security of bridge construction in the northwest of China,and strengthen social infrastructure.This paper introduces some common safety risk assessments,such as expert scoring method,indicator system method and the origin of the risk matrix method.In addition,the Kent index method is chiefly introduced.This method was introduced to the risk assessment about oil pipeline projects.There are two characteristics about the Kent index method.The first,the risk assessment was included in the index.The second,the index weight is more accurate and stringent than the risk assessment.This article takes the construction project of the Maqu yellow river bridge in Gannan area as an example to identify and access the safety risk assessment during bridge construction.First of all,the expert scoring method is used for assessing the construction safety risk of the project example to obtain aggregate risk rating.Secondly,the indicator system method is used for assessing the detailed safety risk of the project example.At last,according to the characteristics of Maqu yellow river bridge construction,summarizes the influential factors,building models,the Kent index method is used for assessing the detailed safety risk.Kent index method of the index contains the factors of risk probability and risk index weight,than the more rigorous and accurate.The Kent index method is based entirely on fact,such as natural environment,human environment,political environment,climate features etc.Adopt the Kent index method,more detailed analysis of specific risk by different influencing factors.By this method,the conclusion of the risk assessment is more correspond,and the control of the risk factors is more targeted.After analysis,the aggregate risk rating of Maqu yellow river bridge construction isGrade Ⅲ.There are four detailed safety risk rating that need to be focused on: foundation pit construction(Grade Ⅲ),Pier column construction(Grade Ⅲ),Cantilever pouring construction(Grade Ⅲ),bridge-erecting machine construction(Grade Ⅱ).To sum up,the safety risk of this huge bridge construction is controllable with a complete contingency plan system in place.The bridge construction is introduced in the Kent index method for safety risk assessment,to fill the domestic bridge construction safety control study deficiencies.It can be used for reference for bridge safety construction management in the future.