Comprehensive Evaluation Method For Bearing Capacity Of Arch Bridge

Arch bridge is a kind of widely used bridge structure with a long history and a typical form.In general,it use the bearing force better pressure resistant material,in order to have the most solid structures and the strongest carrying capacity,ensure the safety of the transport process.However,with the development of traffic,the increase of the vehicle,the damage of the structure,the speed of the construction process and the quality of the construction process and other reasons,more and more in the use of existing arch bridge in the problem of insufficient bearing capacity.When the arch bridge is insufficient,it is easy to become a dangerous bridge,can not be opened to traffic,and even the collapse accident is the serious threat to the safety of the transportation process.In order to ensure the safe use of the arch bridge in the transportation process,it is necessary to carry out a scientific and reliable assessment of the bearing capacity of the arch bridge.In this paper,on the basis of domestic and foreign bridge bearing force detection and evaluation technology research progress,we analyze the current in the existing bridge disease detection and bearing capacity assessment of the main technical means,and the advantages and disadvantages of each method were analyzed.In combination with the practice,the actual disease situation and carrying capacity of the bridge are analyzed and evaluated.Firstly,based on the method of field survey,the structure size and alignment of the bridge were measured and analyzed;Then according to the appearance of observation method of the arch bridge in different parts of the bridge(deck system,superstructure and substructure),in various parts of the appearance of damage were observation and statistics,so as to the evaluation of the disease in existing bridges,and the bearing capacity were preliminary analyzed.Then based on the nondestructive testing method,the strength and carbonation depth of the concrete layer of the arch bridge were tested,and the effect of material properties on the current carrying capacity of the arch bridge was evaluated;At the same time,the loading test of the arch bridge is carried out.Static loading test of bridge are measured in the quantification of different loading grade conditions of strain and deflection change,through the analysis of experimental data,and evaluate the bridge in the existing structure and properties of materials under the conditions of the bearing capacity;In the dynamic loading test,the response of the bridge under different driving conditions of the vehicle is tested,and the bearing capacity of the bridge is evaluated;Finite element model conforming to the characteristics of bridge structure is established by the finite element analysis method,and the model is simulated to verify the accuracy of the model.By applying the design load to the model,the internal force and section resistance of the bridge under different loading conditions are calculated,and the performance of the load bearing capacity of the bridge in the limit state is evaluated;Finally the method of calculating the weight of the bridge is used to calculate the bridge deck system,the superstructure and the substructure of the technical safety status,and the overall safety of the various parts of the bridge was finished in the grade evaluation.This paper mainly through a combination of loading test of the bridge under the condition of different load grade bearing horizontal force and finite element simulation of bridge under the limit condition of bearing force performance analysis,a comprehensive assessment of the existing bridge existing bearing capacity and performance,and needle of the disease and the bearing damage situation proposed reasonable maintenance recommendations.In this paper,the research results can determine the bridge actual bearing capacity level,the speed limit of operation of the bridge,the limit load are proposed,provide the technical basis for the safe operation of the bridge,also for the future bridge maintenance and management to provide the original data.