A nonlinear constraint-surface impact element (CIE) was developed for simulating the pounding in axial direction between 3D shell-element-mesh bridge girders based on the engineering background of ChaoShan airport. Then, a method, different from the previous literatures, for calculating the stiffness of impact element was proposed based on the flexibility method. The methods proposed were adopted and used to analyze the elevated bridge of ChaoShan airport in GuangZhou for the purpose of investigating comprehensively the earthquake-resistance capability. The bridge girders were modeled by shell elements and CIEs were assigned to the positions of the corresponding expansion joints. Isolating elements were used to simulate LRBs, and typical bilinear LRB hysteresis stiffness model obtained from experiment were adopted to describe the dynamic hysteresis behavior. Pounding forces, dissipation capability of LRBs, lateral displacements of LRBs, pier base shear forces and moments as well as the pounding effect on these cases were investigated, respectively. The proposed methods and analysis results aim at improving the earthquake resistance of the elevated bridge, which provides reference for the similar project.%发展了一种适用于体元模拟联间轴向正面碰撞效应的束缚面型碰撞单元(Constraint-sur face Impact Element,CIE);基于柔度法给出了不同以往文献中碰撞单元刚度的计算取值,该取值不仅理论合理且在物理角度可解释其合理性.将该方法应用于广州潮汕机场航站楼高架桥的震致碰撞分析.箱梁采用壳单元模拟,伸缩缝位置设有CIE,桥墩与箱梁间设置隔震单元模拟铅芯橡胶隔振支座(Lead-rubber Bearing,LRB),采用通过试验得到的双线性刚度模型模拟其物理行为.采用非线性直接积分法进行时程分析,主要考察联间的碰撞力、LRB滞回耗能、LRB位移量、基底弯矩、剪力以及碰撞力分别对这些因素的影响.
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