Study On Component Weight Adjustment And Comprehensive Evaluation Method Of CFST Arch Bridge

Concrete-filled Steel Tubular(CFST) arch bridge is one of the main types of long-span arch bridge, which has been built more than 260 in China until 2011. However, many bridges have exposed diseases, such as separation between steel tube and core concrete, anchorage corrosion, vibration, even suspenders and tie bars broke due to corrosion, which seriously affected bridge's durability and safety. To carry out CFST arch bridge's maintenance and management, technical condition evaluation must be firstly performed. However, there are some problems in evaluation method of current Code for Maintenance of Highway Bridges and Culverts, such as the component is incomplete and weight is rough,which caused the actual situation of CFST arch bridge could not be reflected accurately.This dissertation relies on research project "the study on maintenance key techniques of Concrete-filled Steel Tubular arch bridge " supported by Zhejiang Highway Authority, including the following items:①Study on CFST arch bridge weight adjustment method. Because 1-9 scale in raditional AHP existed some problems, the nine level exponential scale was proposed to compute weights of CFST arch bridge components. For complexity of long-span CFST arch bridge, the paper discussed application of the Group-Decision Theory and the Variable Weight Principle in process of determining bridge components weight.②CFST arch bridge component weight computing was studied. The multiple comparison judgment matrices of components weight had been gained by the Delphi. Computing special procedure for MATLAB was developed, which computed each component weight of half-through CFST tied arch bridge.③Evaluation method of CFST arch bridge technical condition was discussed, we proposed the "one-vote negation system " evaluation method.④The research results were utilized in technical condition evaluation of Sanmen Jiantiao bridge in Zhejiang province that was support construction. The evaluation result (Dr=63.8) was slightly smaller than evaluation result for code (Dr=69.8), and reflected really the actual situation of Sanmen Jiantiao bridge, which was better coincide with quantitative analysis.