Q460高强钢简支梁整体稳定极限弯矩计算式研究  

Formula of the Global Buckling Ultimate Moment for Simply-supported Beams with Q460 High-strength Steel

作　　者：李生银 刘占科[2,3] 马张永 LI Sheng-yin;LIU Zhan-ke;MA Zhang-yong(Gansu Construction Investment(Holdings)Group Co.,Ltd.,Lanzhou 730030,China;Key Laboratory of Mechanics on Disaster and Environment in Western China,the Ministry of Education of China,Lanzhou University,Lanzhou 730000,China;College of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,China;Gansu Science and Industry Construction Group Co.,Ltd.,Lanzhou 730415,China)

机构地区：[1]甘肃省建设投资(控股)集团有限公司,兰州730030 [2]兰州大学西部灾害与环境力学教育部重点实验室,兰州730000 [3]兰州大学土木工程与力学学院,兰州730000 [4]甘肃省科工建设集团有限公司,兰州730415

出　　处：《科学技术与工程》2024年第2期723-732,共10页Science Technology and Engineering

基　　金：国家自然科学基金(52278184)。

摘　　要：为揭示《钢结构设计标准》(GB 50017—2017)、《高强钢结构设计标准》(JGJ/T 483—2020)中Q460高强钢梁整体稳定设计方法的差异,提出精确的Q460高强钢梁整体稳定极限弯矩计算式,通过梳理现有文献,提出了钢梁整体稳定极限弯矩的指数形式的一般计算式;根据GB 50017—2017的规定,提出了其稳定系数的统一计算式及对应的“稳定系数-正则化长细比”曲线表达式;提出了理想受弯构件的“稳定系数-正则化长细比”曲线表达式。对比了GB 50017—2017和JGJ/T 483—2020的“稳定系数-正则化长细比”曲线,归纳了其特点,并分析了现有钢梁整体稳定的指数形式极限弯矩计算式存在的问题。基于GB 50017—2017的基准弯矩,提出了Q460高强钢梁整体稳定极限弯矩的指数形式计算式,解决了JGJ/T 483—2020无法直接确定正则化长细比的问题,并采用14个双轴对称、单轴对称工字形截面简支梁的试验数据验证了本文建议公式的精度。研究表明,对于Q460/Q460GJ高强钢简支梁整体稳定的极限弯矩,本文建议的指数形式计算式较现行标准GB 50017—2017、JGJ/T 483—2020中的计算式具有更高的精度。To reveal the differences of the design approaches provided by Standard for Design of Steel Structures(GB 50017—2017)and Standard for Design of High Strength Steel Structures(JGJ/T 483—2020),and to propose more accurate formula for determining the ultimate moment of Q460 steel beam failed by global buckling,a general index-form formula for the global buckling capacity was proposed by summarizing the literatures.Based on the design provision of GB 50017—2017,the stability factor in unified form was proposed,also with the corresponding“stability factor and slenderness ratio”curve.The“stability factor and slenderness ratio”curve of ideal beam was also proposed.By comparing those“stability factor and slenderness ratio”curves,their characteristics were concluded respectively.The problems of index-form formula in current design standards were also pointed out.Based on the analysis on the benchmark moment,a new index-form formula for the global buckling capacity of beams with Q460 steel was proposed.The problem that the slenderness ratio could not be determined in JGJ/T 483—2020 was solved.Test results for fourteen specimens in literatures were used to assessing the precision of the proposed formula.The results shown that,the propose formula for determining the ultimate moment of Q460 steel beam failed by global buckling,is more accurate than the design approaches provided by both GB 50017—2017 and JGJ/T 483—2020.

关 键 词：Q460高强钢梁 指数形式极限弯矩计算式 正则化长细比 基准弯矩 φb-λn b曲线 

分 类 号：TU391[建筑科学—结构工程]