Analysis And Research On Secondary Internal Fore For Long-span Continuous Rigid Frame Bridge

With the development of transportation，prestressed concrete continuous rigid framebridge with its advantages of small deformation, good stiffness, driving smooth andcomfortable, less expansion joints, maintenance simple and anti-seismic ability, has becomean important option for large and medium span bridges structure forms。However, continuousrigid frame bridge belongs to the statically indeterminate structure, prestressing fore, creepand shrinkage of concrete, will make the structure produce great additional internal force(secondary internal fore), so the analysis of secondary internal force effect of continuous rigidframe bridge has realistic significance.In this paper, through consulting the large number of documents, the concept ofsecondary internal fore and secondary internal fore question of continuous rigid frame bridgehave carried on the brief; Introduces the principle and calculation method of prestressed,shrinkage and creep secondary internal fore; Taking a long-span continuous rigid frame bridgein shanxi province as an engineering example, built finite element model, analyse andcalculate prestressing force, shrinkage, creep secondary internal force effect of the continuousrigid frame bridge by finite element software, combined with the characteristics of continuousrigid frame bridge, analyze advantages and disadvantages on the numerical results ofsecondary internal fore; Simulate three closure order conditions, analysis of the effect ofdifferent closure order conditions on secondary internal fore size and distribution ofcontinuous rigid frame bridge, draw some useful conclusions.