考虑环境影响的混凝土梁式桥动力特性及抗震性能演化

项目名称： 考虑环境影响的混凝土梁式桥动力特性及抗震性能演化

项目编号： No.51278031

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 建筑科学

项目作者： 刘保东

作者单位： 北京交通大学

项目金额： 80万元

中文摘要： 混凝土梁式桥在我国公路和铁路工程中应用十分广泛，受环境因素和荷载条件的综合影响，其动力特性和抗震性能也在不断演化，准确把握其动力特性的演化规律对于桥梁安全运营、状态评估及合理养护、加固等都具有重要的理论研究意义和实际应用价值。本课题拟利用理论与试验相结合的方法，从研究混凝土材料弹性模量、阻尼特性的依时变化规律入手，开展环境温湿度和长期荷载作用的影响；结合梁式桥的受力特点，制作混凝土柱、简支梁模型，模拟常规和特定荷载条件（超载、地震等）的影响，进一步分析不同荷载条件对结构自振频率和阻尼的影响；选择混凝土刚构桥梁，分析环境温湿度、荷载条件等对结构的综合影响（如材料特性、应力分布、边界条件、土结相互作用、局部损伤演化等），计算分析其动力特性的演化规律；考虑不同应力水平下结构能量耗散特性，采用基于能量平衡的理论，进一步分析不同地震水平、不同损伤程度条件下的桥梁结构抗震性能。

中文关键词： 混凝土梁式桥；动力特性；环境温湿度；长期荷载；损伤

英文摘要： Abstract: Concrete Girder Bridge is widely used in the highway and railway engineering of China. Its dynamic characteristics and seismic performance are constantly changing by the comprehensive effects of environmental factors and loading conditions. It is of great both theoretical and practical significance to accurately master the evolvement law of its dynamic characteristics for the bridge's safety running, condition assessment, reasonable maintenance and strengthening. By using a combination of theory and experiment methods, this project intends to analysis the time-varying material characteristics such as concrete elastic modulus and damping characteristics firstly. And then study the influence law caused by environmental temperature, humidity and the effects of long-term loading. Combined with the mechanical properties of the girder bridge, concrete column models and simply supported beam models are made. Conventional loading conditions and specific loading conditions (overload, earthquake action) are simulated. The impact of difference loading conditions on the structural natural frequencies and damping are further analyzed. A concrete rigid frame bridge is selected and the combined effects (material characteristics, stress distribution, boundary condition, soil-structure interaction, local-damage evoluti

英文关键词： concrete girder bridge；dynamic characteristics；environmental temperature and humidity；long-term load；damage