(中国建筑西北设计研究院有限公司, 西安 710018)

摘要: 西安国际港务区中轴生态公园人行桥的桥面系采用钢-混凝土组合结构。 采用两阶段受力分析方法对￾混凝土组合桥面系的承载能力极限状态进行验算。 在进行组合桥面系抗弯承载力验算时,剪力滞后效应和钢与混凝土界面剪力传递程度是影响组合结构受力性能的两个关键因素。 钢筋混凝土桥面板采用非线性壳单元模拟,合理地考虑剪力滞后效应对组合梁有效翼缘宽度的影响;抗剪栓钉分别采用非线性弹簧和刚性连接两种方式模拟,合理地考虑界面滑移对组合结构受力的影响。 为控制基础及墩柱尺寸,墩柱与梁体结构连接位置采用高阻尼隔震橡胶支座,进行 E2 地震作用下的隔震验算。 结果表明,采用高阻尼隔震橡胶支座可有效降低墩柱在地震作用下的水平剪力,从而减小墩柱根部的弯矩。 对组合桥面系进行人群有节奏运动的激励与人群自由行走激励两种工况下的舒适度验算,验算结果满足规范要求。

关键词: 人行桥; 钢-混凝土组合桥面系; 两阶段受力分析方法; 滑移效应; 隔震分析; 舒适度验算

中图分类号:TU318+. 2 文献标志码:A 文章编号:1002-848X(2022)11-0064-08

DOI:10. 19701 / j. jzjg. XBY2208

Structural design on footbridge of central axis ecological park of Xi’ an International Trade

and Logistics Park

WANG Lianying, LIU Bin, LÜ Xudong, GAO Zeyu, LUO Guqiu

(China Northwest Architecture Design and Research Institute Co. , Ltd. , Xi’ an 710018, China)

Abstract: The bridge deck of footbridge of central axis ecological park of Xi’ an International Trade and Logistics Park adopts the steel-concrete composite structure. The limit state of the bearing capacity of the steel-concrete composite bridge deck system was checked by two-stage force analysis method. When checking the flexural bearing capacity of the composite bridge deck system, the shear lag effect and the degree of shear force transfer at the interface between steel and concrete are two key factors that affect the mechanical performance of the composite structure. The reinforced concrete bridge deck was simulated by adopting nonlinear shell elements, which reasonably considers the influence of shear lag effect on the effective flange width of composite beams. The shear studs were simulated by nonlinear spring and rigid connection respectively, which reasonably considers the influence of interface slip on the force of the composite structure. In order to control the size of the foundation and the pier column, the high damping isolation rubber bearing was used at the connection position of the pier column and the beam structure, and the seismic isolation check under the action of the E2 earthquake was carried out. The results show that the high damping isolation rubber bearing can effectively reduce the horizontal shear force of the pier column under the action of earthquake, thereby reducing the bending moment at the root of the pier column. For the combined bridge deck system, the comfort degree check was carried out under the two conditions of the crowd’ s rhythmic motion excitation and the crowd’ s free walking excitation, and the check calculation results meet the requirements of thecode.

Keywords:footbridge;steel-concrete composite bridge deck system; two-stage force analysis method; interface slip effect;seismic isolation analysis; comfort check