【摘要】 为了研究北方寒冷地区装配式桥墩节点的冻融损伤规律，基于热力学理论，建立适用于数值模拟的热分析表达式，结合实际工程，采用ABAQUS有限元软件建立1∶6的缩尺模型，从应力、内外温差、塑性应变和位移等方面对装配式桥墩的不同部位开展冻融循环作用下的温度场和冻融损伤分析。结果表明：一次冻融循环作用下，墩帽、墩柱和承台的外表面温度应力与中心点相比，分别增加85%、54%、500%,不同部位呈现一致的变化趋势，即中心点的温度应力变化趋势滞后于外表面；承台中心的温度极值波动最小，说明温度对尺寸较大的构件内部影响较小；随着冻融循环次数的增加，桥墩损伤越来越严重，200次冻融循环作用下，桥墩节点的塑性应变和极限位移均大于其他部位。综合结果来看，装配式桥墩节点是下部结构的薄弱部位。更多还原

【Abstract】 In order to study the freeze-thaw damage law of prefabricated pier joints in the cold area of North China, based on thermodynamic theory, a thermal analysis expression suitable for numerical simulation is established.Combined with the actual project, the ABAQUS finite element software is used to establish the 1:6 scale model, and the temperature field and freeze-thaw damage of different parts of prefabricated piers under freeze-thaw cycles are analyzed from the aspects of stress, internal and external temperature difference, plastic strain and displacement.The results showed that: after the action of one freeze-thaw cycle, the temperature stress on the outer surface of the pier cap, column and foundation increased by 85%, 54% and 500% respectively compared with the center points, showing a consistent change trend, that was, the change trend of the temperature stress at the center points lagged behind the outer surface.The temperature extreme value fluctuation in the center of the foundation was the smallest, indicating that the temperature had less influence on the interior of the larger component.The damage degree of pier joints was positively correlated with freeze-thaw cycles.Under the action of 200 freeze-thaw cycles, the plastic strain and ultimate displacement of the bridge pier joints were larger than those of other parts.According to the comprehensive results, the prefabricated pier joints were the weak parts of the substructure.更多还原