S型曲线小半径连续窄箱室钢混组合梁设计要点及受力研究

Design points and stress analysis of S-shaped curved small radius continuous narrow box room steel-concrete composite beam

文章依托某项目4 m×45 m连续窄箱室钢混组合梁,介绍了连续窄箱室钢混组合梁的构造设计,采用有限元软件进行数值分析。设计出一种窄箱式钢梁和有承托混凝土桥面板结合的钢混组合梁截面形式。钢混组合梁增大了组合截面的刚度,减小了梁的挠度;提高了梁的基频,利于结构的抗震设计;整个截面重心的抬高,钢梁的腹板较大一部分处于受拉区,避免钢梁腹板产生“呼吸效应”。文章总结了钢混组合梁较常规结构的优缺点,构造上经优化后可为同类型桥梁方案提供设计参考。

This paper relies on a 4 m×45 m continuous narrow box room steel-concrete composite beam on ramp A.It introduces the structural design of steel-concrete composite beam with continuous narrow box room and carries out numerical analysis with finite element software.A cross-section form of steel-concrete composite beam combining narrow box steel beam and supported concrete bridge deck is designed.The steel-concrete composite beam increases the stiffness of the composite section and reduces the deflection of the beam.It improves the fundamental frequency of the beam and is beneficial to the seismic design of the structure.With the elevation of the center of gravity of the whole section,a large part of the web of the steel beam is in the tension zone,so as to avoid the“respiratory effects”of the web of the steel beam.This paper summarizes the advantages and disadvantages of steel-concrete composite beams compared with conventional structures,which can provide reference for similar bridge schemes after structural optimization.