Study On The Temperature Effect Of Prestressed Concrete Box-girder

In society now, with the bridge construction technology continues to improve and theconstant improvement of the construction machinery and equipment, construction of bridgeconstruction of our country and even the world have leap-type development, which not onlypromote the rapid development of the cause of building, but also promote the entiregreatlyimprovement of human life. Box girder structure, in which have excellent performance,standing out in the bridge section and forming a very wide range of applications in thecontinuous beam. In some areas, however, especially in China’s northwest relatively largetemperature difference between day and night areas, box girder stress and deformationgenerated by the temperature effect produce a tremendous impact on the safety, durability andapplicability of the bridge. In the actual project, many of prestressed concrete box girderstructure due to not fully take into account the impact of the temperature effect, making thebridge a lot of cracks and causing a serious security risk.Taking Gansu wicker River Bridge as the experimental basis, combined with localtemperature, climate, environment and other conditions, we have a one-year observation andanalyze the temperature distribution and variations of the typical climate of the differentseasons of the bridge.Then through the local temperature field analysis, I sum up the law of the temperaturedistribution of the box girder bridge suited to local environmental conditions.,Couduct thevertical temperature gradient in the region,and come to the region of the vertical temperaturegradient,.in the end, through the establishment of the bridge thermal stress simulation model,analysis and research bridges temperature effect.The research topics include the following four aspects:（1）By observing the temperature of the continuous box girder bridges to research thetemperature distribution.（2）Research on temperature field, and with reference to the relevant provisions of thespecification drawn for the region the temperature gradient mode.（3）The feasibility of the finite element calculation software ANSYS, based ondomestic and international norms on the temperature field numerical analysis, analysis offinite element software simulation of concrete box girder temperature field.（4）By the finite element software to simulate the internal force, stress and deflection of box girder structure under different temperature gradient and analysis in differenttemperature gradient mode, the temperature effect of the structure.