Research On Deflection Control Under The Temperature Load Of Large Span Continuous Beam Bridge

With the development of the transportation industry,we improved the new technologies,new theories and new technology.Bridge construction has been rapid progress.It played a pivotal role in a transportation network and promoting the development of the national economy.But as the temperature difference increases and the change in the amount of traffic,the bridge structure cracks.Excessive cracks will reduce the effective area of the structure.It affected the applicability and reliability of the bridge,even the people's lives.The safety and durability of the bridge are constantly being tested.When the Long-span concrete box girder bridge under the influence of natural factors like The temperature plummeted,Seasonal temperature change,Solar radiation,it will be crack and even broken to have an accident.As the temperature gradient pattern is diverse,the calculated temperature stress and deformation are different,It is necessary to analyze and study the temperature effect in different modes.In this paper,the principle,method and effect of temperature load design in the specification of China,America and Europe are analyzed and compared comprehensively.The short-term and long-term changes in the deflection of bridges under different temperature loads,Taking the Qinglong River Bridge as the engineering background,using the finite element analysis software MIDAS / Civil,full bridge with space beam element.According to the cross section characteristic,the calculation model of Qinglong River Bridge is established.Respectively,in accordance with the provisions of the provisions of the China,the United States and Europe to determine the design parameters of the bridge under the temperature load calculation and analysis.Get the internal force,the upper and lower edge stress,deflection and other calculation data,and the influence law of deflection is analyzed.This paper discusses the difference between the temperature and load setting and the deflection of the bridge in the specification of the china,the US and European bridges from the perspectives of stress change,deformation effect and influence range.Finally,according to the results of the model calculation,Comprehensive comparison the Short-term and long-term changes in bridge deflection under the loadof temperature.Discussed The advantages and disadvantages of each country in temperature load design.The influence of the deflection on the bridge is analyzed,and the deflection development is controlled.Proposed optimization of the design method of temperature load in the bridge design specification of our country is put forward.