| Abstract:This thesis focuses on concrete bridges camber setting problem in the context of cross Lian-huo high way railway bridge. At first, the field short-term tests are used to modify creep prediction model. Then combined with the finite element software, the modified model is applied to do research on the concrete bridge camber. The research results are as follows:(1) The basic theory, calculation method and prediction model of creep are investigated to provide background and theoretical support for the modified model. According to the actual bridge data and the element model, different theoretical prediction models are applied to calculate bridge camber. After being compared, those results reveal the characteristics of various theoretical prediction models when they are used to calculated bridge camber.(2) As for designing short-term creep experiments, three common theoretical prediction models-ACI209, CEB-FIP1990and TB10002.3-2005-are used to fit measure data of short-term creep test. Based on the fitting results, the creep coefficient function and the modified creep prediction model be got.(3) The bridge camber settings results are calculated by using three modified creep prediction models and finite element software. The results are studied in the following two aspects respectively:â‘ the bridge camber values are calculated with three primary creep prediction models. The initial coefficient of variation and modified coefficient of variation are compared.â‘¡short-term vertical displacement of different bridge segment are calculated by using three creep prediction models. The calculation results are compared with the ones collected in the field.The research shows that the modified CEB-FIP1990creep prediction model is a better one. When the concrete bridge camber is calculated, considering the effect of short-term creep on effectively improve the accuracy of bridge camber calculation and provide a new approach for concrete bridges camber setting. |
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