摘要
为研究混凝土格构式桥墩几何参数对连续刚构桥地震响应的影响,以某(65+4×120+65)m连续刚构桥为背景,建立全桥有限元模型,采用反应谱法和非线性时程法分析混凝土格构式桥墩单肢截面尺寸、单肢纵向间距、系梁道数对该桥动力特性和地震响应的影响规律。结果表明:混凝土格构式桥墩单肢截面尺寸、单肢纵向间距、系梁道数对连续刚构桥的各阶振型基本没有影响;随着单肢截面尺寸、单肢纵向间距的增大及系梁道数的增加,连续刚构桥自振频率均逐渐增加,其中系梁道数对其影响较大,随着系梁道数的增加,该桥1阶、2阶自振频率逐渐增加;罕遇地震作用下,随着单肢截面尺寸、单肢纵向间距的增大及系梁道数的增加,桥墩位移逐渐减小;随着单肢截面尺寸的增大,桥墩内力明显增加,而单肢纵向间距对桥墩内力影响较小;随着系梁道数的增加,桥墩剪力逐渐增加,而墩顶及墩底弯矩逐渐降低;单肢截面尺寸、单肢纵向间距、系梁道数对墩顶、墩底塑性转角影响很小,但是墩顶、墩底塑性转角随格构式桥墩单肢截面尺寸的增大呈先增大后减小的趋势。
This study investigates the influence of geometrical parameters of concrete bent piers on seismic responses of the continuous rigid-frame bridge.Based on the finite element model of an existing continuous rigid-frame bridge with four main spans of 120 m and two side spans of 65 m,the influences of three primary parameters on the dynamic property and seismic responses of the bridge were analyzed using the response spectrum method and the non-linear time history method,including the cross-sectional dimension of a single leg of the pier,spacing of pier legs,and amount of tie beams.It is shown that the three parameters have no influence on different modes of vibrations of the continuous rigid-frame bridge.As the values of the three parameters increased,the natural frequencies of the continuous rigid-frame bridge gradually rose,and the impact of the variation of tie beam amount was the most remarkable.Adding tie beams caused the gradual increase of the first-and second-mode natural frequencies.Under rare earthquakes,the increase of these three parameters led to the reduction of the pier displacements.Enlarging the cross-sectional dimension of a single pier leg resulted in the increase of the internal forces of the piers,while the influence of longitudinal spacing of pier legs was minor.The amount of tie beams was directly associated with the variation of shear strengths of the piers,more tie beams,greater shear strengths of piers,while seeing the reduction of the pier-top and pier-bottom bending moments.The three parameters exerted slight influence on the plastic rotation angles at the pier top and pier bottom.As the cross-sectional dimensions of individual pier legs increased,the pier-top and pier-bottom plastic rotation angles changed from increasing to decreasing.
作者
赵文斌
张戎令
武维宏
高新民
刘益麟
ZHAO Wenbin;ZHANG Rongling;WU Weihong;GAO Xinmin;LIU Yilin(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Gansu Provincial Transportation Planning Survey and Design Institute Co.,Ltd.,Lanzhou 730030,China;Gansu Luqiao Third Highway Engineering Co.,Ltd.,Lanzhou 730030,China)
出处
《世界桥梁》
北大核心
2024年第6期87-93,共7页
World Bridges
基金
甘肃省交通运输厅揭榜挂帅制科研项目(202102)
甘肃省科技重点研发计划项目(21YF11GA011)
交通运输部交通运输行业重点科技项目(2021-ZD2-073)。
关键词
连续刚构桥
混凝土格构式桥墩
桥墩参数
动力特性
地震响应
有限元法
continuous rigid-frame bridge
concrete bent pier
pier parameter
dynamic property
seismic response
finite element method
