Study On Mechanical Properties Of Prestressed Concrete T-beam Continuous Bridge Under Dangerous State

Prestressed concrete T-beam continuous bridge is not only with smalldeformation, stiffness, less the number of joints, etc., but also driving comfort,convenience, construction and maintenance, usually, which is preferred by the ownersin various types of bridges.In several construction methods of T-beam continuous bridge, simply supportedand continuous construction method is a cost-effective construction method,compared with ordinary concrete girder bridge, this method is low cost, convenientconstruction, shorter cycle, which is welcome by the designers and workers.But in our country, simply supported continuous beam bridge is still in thedevelopment stage, relatively, construction technology and equipment is backward,during the construction and use, causing many problems and diseases, resulting insubstantial economic loss, so it is necessary to research and analyze the diseases.In this paper, we use finite element software Midas/Civil, with typical T-beamprestressed continuous bridge as the research object, simulating and analyzingthrough its overall superstructure.Analysis of bearing defects showed, bearing void and abnormal deformation onthe structure forces are both serious, bearing void in side beam is worse than in themiddle beam.Through analyzing the influence on the structure under different loss of negativemoment tensile stress, the main influence mainly in the vicinity of the bearing section.In addition to a significant impact on the negative moment where the main beam force,but also had an impact on its neighboring main beam, the other main beams spaced nosignificant change.The analysis of construction sequence showed that the same pier at the top ofeach piece main beam negative moment tensioned construction sequence, thesymmetric stretching select the girder negative moment each piece of steel beam;longitudinal bridge construction sequence, first of all the main beam between pouringwet seams, and then pouring or symmetric interval pouring wet joints and tendontensioning negative moment.Finally, we use the finite element software ANSYS consecutive segments wetpart of the local joint, analysis of its bridge stage showed that the middle section and the bottom edge of the wet part of the joint vulnerable to large tensile stress,reinforcement ratio should be raised here, using high-strength concrete and othermethods to enhance structural rigidity and reduce prestressing losses.