Analysis Of Temperature Field And Thermal Stress On Continuous Rigid Frame Aqueduct

Aqueduct is an overhead construction of the water conveyance structure, usuallybuilt across the obstacle crossing construction of channel, road, mountain, valley etc. Itplays an important role in the canal water building and is one of the widely used crossbuildings. With the continuous application of new technologies and new materials, thescale is also increasing. Qianzhong Water Conservancy Diversion Project is the biggestin Guizhou province, the water flow, water depth and water load of the aqueduct arealso great, the scale is in the forefront of the world. But the research of large aqueduct isfar lagging behind, especially for the sunshine temperature field and temperature stresswhich caused the aqueduct cracks. Therefore, On the basis of accessing to a largenumber of documents, this paper takeS XUjiawan Aqueduct Engineering as an example.Through theoretical analysis and finite element simulation, the research on temperaturefield and temperature stress of the aqueduct structure has important practicalsignificance. Main contents of the research work as follows:(1)On the basis of domestic and foreign present literature and research results,discussed the problem of temperature cracks of aqueduct in China, analyzed the reasonscaused the temperature cracks, and the characteristics and harm of temperature crackswere also summarized.(2)Analyzed the reasons of temperature gradient generated by aqueduct boxgirder bridge, and described constants, parameters, boundary conditions specifically incalculating the temperature loads.(3)Through the theory of heat conduction and thermal load, Used Midas FEAsoftware to establish the simulation model of Xujiawan Aqueduct Bridge to analyze itstemperature effect. Through the aqueduct temperature distribution results, and combinedwith the domestic and foreign related standards, using quadratic curve, fitting thetemperature curve of the aqueduct sections, finally calculating the correlationcoefficient values. Then made a comparative analysis of fitted temperature gradientcurve and the temperature curves in highway and railway codes.(4)Through the analysis of aqueduct temperature field, the aqueduct temperaturestress were studied of sunshine temperature changes. Described inside and outsidesurface temperature stress changes of aqueduct bridge’s roof, web and floor part insummer sunshine temperature effect. Then summarized aqueduct bridge’s X, Y, Z direction stress change rules in summer sunshine temperature effect.(5)Took some measures of setting thermal insulation boards to the aqueductbridge’ temperature cracks caused by temperature stress, and the analysis is verified bythe finite element model.