Research On Level 2 Safety Evaluation Method Of Degenerative Concrete Filled Steel Tube Arch Bridge Based On Multivariate Information

Since the introduction of concrete-filled steel tube arch bridge into China,because of its good material properties and mechanical properties,it has mushroomed in China.At the same time,with the occurrence of some concrete filled steel tube arch bridges collapse,suspender fracture and bridge collapse,the operation safety of CFST arch bridge has been paid close attention during the long term service.In order to grasp the actual safety situation of CFST arch bridge during service,this paper proposes a level 2 safety evaluation method for assessing safety performance of the bridge by updating finite element model and load model of CFST arch bridge,which is based on multivariate information including actual detection information and monitoring information.First of all,the engineering situation of Chuanyang River CFST Arch Bridge was introduced,which was the subject in the study.The local damage information,the whole structure characteristics and the actual load situation of Chuanyang River CFST Arch Bridge during service was got from two aspects of the detection and monitoring of the actual acquisition,which was the information base of updating finite element model and load model of Chuanyang River CFST Arch Bridge and determine its safety status.Secondly,the finite element model of Chuanyang River CFST Arch Bridge was established,and component finite element model was updated based on detection and monitoring information which can reflect the status of the CFST arch bridge local damage.The global finite element model was updated through the method of structure parameters sensitivity analysis based on the overall response of CFST arch bridge.And measured load model was built based on load monitoring information,load model was updated by comparing design load model with measured load model.The updating finite element model could reflect the actual situation of the research object,and the updating load model could reflect the actual loading condition,which provided the basis for the subsequent structural safety level 2 assessment.Finally,on the basis of the updating finite element model and load model,the safety state of components was obtained by reanalyzing updated model,and ultimate bearing capacity analysis was conducted to gain structural safety reserve.Then the result of Component and global safety evaluation showed the structural safe state,and level 2 safety evaluation of Chuanyang River CFST Arch Bridge was complished.The level 2 safety evaluation method of degenerative concrete filled steel tube arch bridge based on multivariate information,which was proposed by this paper,makes full use of structure detection and monitoring information,and can reflect safety state of the structure in the actual service,and the information is easy to obtain,so it has good reliability,economy and feasibility.