Study On Seismic Strengthening Performance Of Fabricated Column Joints On Arch Based On Dynamic Constitutive Relationship

When we meet mountains,we need to build roads,and when we meet rivers,we need to build bridges.Bridges are very important to us.The service condition of bridges determines whether they can quickly open the lifeline of rescue and disaster relief.However,a large part of the existing bridges in China have been built and used for more than 30 years.Because there’s no money and insufficient attention to the structural seismic performance,many bridges could not meet the fortification standard of the current seismic code,and the probability of damage after the earthquake was higher.Therefore,it is urgent to carry out seismic research on arch bridges.According to the science and technology project of Yunnan Provincial Department of transportation,based on the research results obtained by the research group,this paper selects three kinds of reinforced columns and original columns with remarkable reinforcement effect for research and analysis,and takes three box arch bridges with different spans as the research object for seismic analysis.Did the following things:(1)Based on the research results obtained by graduate students,this paper arranges and analyzes the quasi-static cyclic loading test data of original columns,steel plate reinforced columns,steel bar reinforced columns and FRP reinforced columns,and analyzes the seismic performance of four kinds of columns from multiple angles,such as load displacement curve,reinforcement stress-strain curve and residual displacement at the top of columns.(2)The numerical model is established according to the test components.Simulation with software test process of the component,and the results calculated by force of contrast.Verify the consistency between the test results and the simulation results.(3)When analyzing the seismic response of the whole bridge,according to the bridge type and span of the bridge and the provisions of the seismic code,During seismic analysis of the whole bridge,we should not only consider the seismic action in two horizontal directions,but also consider the impact of vertical seismic action at the same time.Due to the elastic-plastic analysis of bridges under rare earthquakes,it is necessary to consider the nonlinearity of materials.Three deck box arch bridges with spans of 100 m,130m and 150 m are selected.The rotation angle and section internal force of the column top and column bottom of the column on the bridge arch are discussed,and the causes are analyzed.Analyze the whole bridge after column reinforcement,and study the influence of different column reinforcement methods on the seismic performance of the whole bridge system.(4)According to the conclusions of component test,numerical simulation and elastic-plastic analysis of the whole bridge model,the column of a deck box arch bridge is strengthened by steel plate reinforcement method,so as to improve the stiffness and ductility of the column on the arch,and then improve the seismic performance of the whole system,so as to better progress the seismic reinforcement of deck arch bridge.