为明确地震作用下城市高架曲线桥上部梁体位移响应规律,基于ANSYS软件有限元分析,开展了不同水平、不同类型地震作用下上部梁体位移对比研究。研究表明:地震作用下曲线梁桥上部梁体主要表现为切向位移,罕遇地震作用下最大切向位移较最大径向位移增加约1.45倍,出现在端跨桥台位置,该位置应加设纵桥向防落梁装置;最大径向位移出现在中跨位置,应加设横桥向防落梁装置,多遇地震作用下无需加设防落梁装置。罕遇地震作用下,每联桥梁中部墩底截面曲率易超出屈服曲率值而进入塑性,选取的日本海中部T1-111-1地震波振动频率大,各点地震强度强烈,墩底滞回曲线密集。地震作用下曲线梁桥结构上部梁体位移响应规律研究有助于分析地震作用下曲线梁桥结构的损伤特点,在明确城市高架曲线桥防落梁装置研究方面具有重要作用。
Based on the ANSYS finite element analysis method, the under different types and level seismic action was studied to clear the di displacement response of upper beam splacement response rule of the upper beam of urban curved bridge under the action of earthquake. Research showed that: Tangential displacement is the main displacement response of curved bridge upper beams under different seismic action, and the maximal tang ential displacement appears at bridge abutment, placement at bridge mid-span. So it is necessary to which increases by 1.45 times than the maximal radial disset longitudinal collapse-proof systems at bridge abutment and transverse collapse-proof systems at mid-span, and it is unnecessary under frequent earthquake. Normally sectional curvature of pounding bottom at bridge mid-span exceeded the limit easily under rare earthquake, entering plastic deformation. Due to the vibrational frequency of T1-111-1 seismic wave was larger, the hysteretic curve of pounding bottom concentrated. The study on displacement response of curved bridge upper beams under different seismic action helped to clear the damage characteristics, and it played an important role in collapse-proof systems of urban viaduct curved bridge.