建筑结构学报2025，Vol.46Issue(3)：38-49,12.DOI:10.14006/j.jzjgxb.2024.0374
大跨度变截面连续组合梁受力分析和设计方法研究
Mechanical analysis and design method of large-span variable cross-section continuous composite beams
摘要
Abstract
Large-span variable cross-section continuous composite beam was beneficial to increasing the net height and saving steel consumption.To obtain the mechanical properties and reasonable shape characteristics of large-span variable cross-section continuous composite beams,numerical simulations were conducted to evaluate the applicability of traditional modeling techniques of variable cross-section segment,for different variable cross-section segment position,slope,and the height difference between middle and end spans.A theoretical model for variable cross-section composite beams under static vertical loads was established,and an analytical method was proposed to obtain the length of the negative bending moment zone,the internal forces and deformations of each key section.Parameter analysis on six types of parameters related to steel beams and variable cross-sectional shapes was conducted.It is found that when the cross section approached the mid span,the length of the negative bending moment zone and the proportion coefficient of bending moments at the beam end and mid span increased first and then decreased.It is suggested that βs=0.25～0.30,βh=0.55～0.60,and the equivalent safety design principles should be checked.The critical condition in which seismic condition controlled the load bearing capacity of large-span structures was studied.The rare earthquake elastic-plastic time history analysis was conducted on a three span variable cross-section continuous composite beam planar frame structure using a refined finite element analysis model.It is found that the structural response under near field earthquakes is greater than that under far field earthquakes,and the maximum internal force of the steel beams is about 54％of that under the static service condition.The steel beam in the variable cross-section continuous composite beam still maintains elasticity under rare earthquakes,which indicates a sufficient safety reserve.关键词
大跨度结构/组合梁/变截面/数值模拟/静力性能/抗震设计Key words
large span structure/composite beam/variable cross-section/numerical simulation/static behavior/seismic design分类
土木建筑引用本文复制引用
甄伟,聂鑫,李伟,邱意坤,丁然,樊健生,张磊,张龑华..大跨度变截面连续组合梁受力分析和设计方法研究[J].建筑结构学报,2025,46(3):38-49,12.基金项目
国家自然科学基金杰出青年科学基金项目(52325802). （52325802）
