Analysis And Evaluation Of Bearing Capacity Of CFST Arch Bridges In Service

As a structural type of arch bridge,CFST arch bridge has the advantages of light weight,strong bearing capacity and large spanning capacity,and is one of the ideal structural types among long-span bridges.Therefore,CFST arch bridges have been widely used and developed in recent years.However,as the service life of bridges increases year by year,many CFST arch bridges that have been built have begun to suffer from different degrees of disease,resulting in insufficient bridge bearing capacity,reduced safety reserves,and some bridges have even lost their bearing capacity.Therefore,it is necessary to efficiently,accurately and objectively evaluate the actual bearing capacity of the bridge to determine whether it meets the requirements of the safe operation of the bridge.To sum up,under this background and the current actual situation,the development of this thesis has important scientific and practical significance.In this paper,the following researches are carried out on the bearing capacity evaluation of CFST arch bridges:(1)On the basis of summarizing the existing bridge bearing capacity assessment methods and theories,this paper studies the bridge bearing capacity assessment process in detail in combination with the latest highway bridge bearing capacity assessment standards promulgated by the Ministry of Transport.Based on the conventional test results,the calculation formula of the bearing capacity is modified by introducing the sub-item check coefficient,and the bearing capacity of the CFST arch bridge is calculated and analyzed by combining with the finite element.method of carrying capacity.(2)After studying and analyzing the two test methods of static and dynamic load test,this paper summarizes the evaluation indexes which can reflect the bearing capacity of CFST arch bridge in static and dynamic load test,and establishes the method of evaluating the bearing capacity of CFST arch bridge based on the test.(3)Based on the comprehensive analysis of various evaluation methods of test results and the bridge structure based on the existing disease characteristics,according to the concrete filled steel tubular arch bridge bearing capacity evaluation index multi-level and multi-factor and characteristics of coexistence of qualitative and quantitative indicators for the bearing capacity of the traditional method without considering the characteristic of concrete filled steel tube arch bridge diseases,A comprehensive evaluation method for bearing capacity of CFST arch bridge based on triangular fuzzy number is proposed.