Safety Evaluation And Analysis Of High Pier Construction Technology Of Wanli Expressway

With the development of China’s economy,expressways continue to extend to mountainous areas.More and more expressways are built in mountainous areas across rivers and valleys.In order to avoid geological disasters and environmental impact caused by deep excavation and high filling,and at the same time,it is necessary to take into account the line design standards.For the sections where the route crosses rivers and deep valleys,high piers and high towers are often used Taking the construction practice as an example,the paper systematically analyzes and summarizes four construction technologies of high pier and high tower,including hydraulic climbing formwork,turnover formwork,sliding form and roller formwork construction of bridge pier column,carries out safety risk assessment and analysis from the aspects of process principle and system structure,and scientifically and reasonably compares and selects appropriate safety risk assessment methods.In this paper,LEC risk method and fuzzy evaluation method are used to carry out general risk analysis and comprehensive analysis and evaluation on the four kinds of pier column construction technology.According to the four construction technologies of hydraulic climbing formwork,turnover formwork,sliding form and roller formwork construction,the quantitative evaluation results of LEC risk method show that the risk of biological attack accident during the construction of No.9 pier hydraulic climbing formwork of Fuma Yangtze River Bridge is grade 4 high risk,and the tower crane overturning construction of No.11 pier of Fuma Yangtze River Bridge causes biological strike,falling from height and collapse Therefore,the risk is level 4 high risk;the risk of biological attack,falling from height and collapse during the sliding form construction of No.11 pier column of xuejiaba No.2 bridge is grade 4 high risk;the risk level of biological strike accident in the construction process of No.13 pier column roller formwork of fengziwan super large bridge is grade 4 high risk.The general risk analysis and evaluation results of LEC method can be used as the safety reference of four kinds of bridge construction technology Test.The fuzzy evaluation method is used for comprehensive safety evaluation,and the safety evaluation index system of high pier construction technology is established,and the index system is analyzed.The qualitative index is quantified and the weight of each index is determined.The results of fuzzy comprehensive evaluation show that: the comprehensive evaluation score of fengziwan bridge No.13 pier column roller formwork construction is the highest,and the comprehensive score reaches the good standard,which is higher than the other three high pier construction technology safety;the hydraulic climbing formwork construction score of No.9 pier of Fuma Yangtze River Bridge ranks the second,which is higher than that of turnover formwork and slip form construction,reaching a good standard;the score of slip form construction of xuejiaba No.2 bridge is higher The comprehensive score of tower crane turnover formwork construction of No.11 pier of Fuma Yangtze River Bridge is the lowest,only reaching the medium standard.After comprehensive analysis and evaluation,the final conclusion is that without considering the hydraulic climbing formwork,turnover formwork,sliding mode,roller formwork construction progress,efficiency,economy and other factors,only from the perspective of construction safety analysis and comparison of the four high pier construction technology,after the comprehensive evaluation of safety management,the roller formwork construction score is the highest,the comprehensive safety situation is better than the other three construction technologies,hydraulic climbing formwork Secondly,the tower crane turnover formwork construction score is the lowest.It is suggested that the construction technology of roller formwork should be optimized without considering the construction schedule,efficiency and economy.The comprehensive score of tower crane turnover formwork is the lowest,and the possibility of accidents is high.This technology should be avoided in the construction process.Finally,according to the accident risk assessment results,according to the risk acceptance criteria,and according to the different high pier construction technology safety risks,take corresponding safety control measures to eliminate or reduce the risk of risk,reduce the probability of safety accidents,and put forward the corresponding safety control measures and hidden danger treatment countermeasures and suggestions.