Steel Cofferdam Construction Risk Assessment Of Municipal Bridge Based On FTA-BIM

In recent years,China's water municipal bridge construction has been continuously developed.Steel cofferdams have become one of the most common types of water foundation support due to their many advantages such as good stability and waterproof retaining performance.As the construction environment continues to be complicated,the risk of steel cofferdam construction continues to rise.Therefore,in order to reduce the casualties and losses caused by steel cofferdam construction,this thesis combined support vector machine(SVM),fault tree analysis(FTA),BIM technology and other related theories to systematically analyze the risk assessment of steel cofferdam construction on water.The main contents are as follows:(1)Combined with the influencing factors such as weather forecast and adjacent water system,the medium and short-term water level prediction in complex hydrogeological environment was established from the perspective of engineering actual demand,and the sample set was combined with engineering examples to carry out SVM training test and calculation analysis;(2)In view of the dynamics of water level change,the complexity of steel cofferdam construction risk and the shortcomings of traditional risk assessment methods,this thesis took SVM water level prediction as the key support technology,dynamically depicts the influence of water level factors through update forensics,and then combined FTA with Qualitative and quantitative analysis,the advantages of BIM in data integration and visualization,the risk assessment model of steel cofferdam construction based on FTA-BIM was proposed,and the overall framework and application process of the model were expounded to realize the dynamic update of hydrological data of steel cofferdam construction and visualization of risk assessment;(3)By taking a caisson of Xinhe Bridge in Wuhan as an example,the FTA-BIM model was used to study the risk of pipe seepage.Firstly,the BIM model of steel cofferdam structure and hydrogeology was constructed,and the FTA model was constructed by risk identification.Secondly,the fault tree was used to calculate and analyze the model qualitatively and quantitatively.Finally,the risk visualization and response were carried out.Based on the actual engineering case,this thesis comprehensively analyzed and verified the applicability and reliability of FTA-BIM steel cofferdam construction risk assessment model,and provided new ideas and references for municipal bridge engineering construction risk assessment.