Study On Safety Evaluation Theory And Method Of CFST Arch Bridge

The concrete filled steel tubular (CFST) arch bridge has developed greatly recent years with peculiar mechanical properties and technological advantages. Because theory research lags behind engineering practice, there have been many problems exposed in CFST arch bridges, and that have caused bad social influence and huge economic losses. With safety becoming increasingly urgent, in order to ensure safe operation of bridge, it is necessary to evaluate on the safety of engaged bridges. At present, the bridge evaluation part of current maintenance code have defect of bridge type shortage and component weight roughness, that will affect on correctness and reliability of bridge evaluation results.Based on"Study on Maintenance Key Technology of CFST Arch Bridge", which is the project of Zhejiang province communications department, researches of safety evaluation theory and method of CFST arch bridge have been completed, and the contents are presented as follows:①Bridge safety evaluation closely relates with load-bearing capability of components, but current safety evaluation methods of CFST arch bridge simply account disease condition as only evaluation index, which neglect design load-bearing capability, and it is incompletely unreasonable to evaluate safety of components. Therefore, the index which took design load-bearing capability and disease condition into consideration was put forward to evaluate safety of CFST arch bridge.②Traditional analytic hierarchy process adopts"1-9"scale to define importance between two indexes, and comparison matrix formed by"1-9"scale possibly cause a matter that evaluation result differ with consistency of human thinking. Exponential scale method was introduced into bridge safety evaluation for the first time, and component weights were calculated using exponential scale based analytic hierarchy process.③Component types were classified detailedly, and component weights were calculated, moreover, the perfect safety evaluation index system was established considering component evaluation indexes, and the safety evaluation method of CFST arch bridge was put forward.④The safety evaluation method was applied in Jiantiao bridge of Sanmen Zhejiang province, finite element software ANSYS was used to calculate load-bearing capability of forced components, and based on the established safety evaluation index system, safety evaluation was made associating with inspection results. The CFST arch bridge safety evaluation system was exploited using Visual Basic language, and evaluation results coincide with actual bridge condition.