【作者】 刘鹏；

【导师】 郑周练； 王耀伟；

【作者基本信息】 重庆大学 ， 工程硕士（建筑与土木工程领域）（专业学位）， 2017， 硕士

【摘要】 GJ钢作为适应于大跨空间钢结构以及超高层钢结构的高性能材料,已经在众多重要建设项目中得到应用。相比于普通的低合金高强度结构钢,GJ钢具有良好的应用前景。但是针对GJ系列钢材的试验研究工作比较少,设计参数的指标还未纳入相关规范中,这些都阻碍了GJ钢的应用与推广。所以对于GJ钢,尤其是高强度的GJ系列钢仍有许多基础研究工作要做。基于前期对于Q460GJ钢研究的系统性筹备,本文对Q460GJ钢焊接H形截面轴压构件进行了整体稳定性能的试验研究、轴压构件整体稳定性能的有限元分析和Q460GJ钢焊接H形构件的柱子曲线的研究。试验研究针对的是基于前期的材性试验与残余应力试验之后而开展的长柱轴心受压试验的研究。材性试验的板厚对应于后面试验有12mm,25mm和42mm三种规格,残余应力试验所测定的构件按照翼缘板和腹板的厚度不同分为两大类、8种截面规格。长柱的轴压试验所研究的构件按照截面规格和长度分为14根构件,其截面规格同残余应力试验一致。试验研究针对的是长柱绕弱轴方向的失稳。轴压构件的整体稳定性能的有限元分析部分,建立了同时将几何初始缺陷及残余应力考虑在内的有限元分析模型,并详细介绍了有限元模型的建立过程;同时将有限元分析结果与试验结果进行对比,验证了模型的准确性与可靠性,并与规范理论值进行比较。柱子曲线的研究部分,计算了针对不同回转半径、截面规格与长度共计208个构件的整体稳定系数,并与中美欧的钢结构设计规范进行对比,提出了Q460GJ钢焊接薄型和厚型H形构件柱子曲线的类型选取的建议,为Q460GJ钢焊接H形构件在工程应用及研究提供了一种设计方法。本文创新点如下:(1)通过本课题的研究,将有利于发挥Q460GJ钢在构件层面上体现出来的性能优点,并通过相应的设计参数反应出来,服务于国内的重大工程项目需要。(2)通过引入团队之前得到的残余应力的分布模式,并将几何初始缺陷的因素考虑在内,可以准确分析Q460GJ钢焊接H形轴心受压构件的整体稳承载力。(3)设计合理的试验方案,获得更为合理的Q460GJ钢轴心受压构件整体稳定试验承载力极限值;通过参数化分析获得数量众多的柱子曲线,并与各国规范进行比较分析,从而给出更合理的曲线选择的建议。同时丰富和充实了GJ钢轴心受压构件性能数据库,为利用结构可靠度理论分析获得Q460GJ钢焊接H形轴心受压构件的计算模式不定性奠定基础。更多还原

【Abstract】 As a kind of high performance material which is suitable for large span space steel structures and super high-rise steel structures,GJ steel has been used in many important construction projects.Compared with common low alloy high strength structural steel,GJ steel has a good application prospect.However,for the GJ steel,the research work is relatively scarce,and the design parameters are not included in the relevant specifications,which hinder the application and promotion of GJ steel.So for GJ steel,especially for high strength GJ series steel,there are still a lot of basic research work to do.Based on the prophase preparation for the research work of Q460 GJ steel,in this paper,the experimental study on the overall stability of Q460 GJ steel welded H section axial compression members,the finite element analysis of global stability of axial compression members,and Study on the column curves of Q460 GJ steel welded H section members are carried out.The experimental research mainly includes the long column axial compression test,which is mainly based on the previous material test and residual stress test.The material properties test has 12 mm,25mm and 42 mm these three specifications of the plate thickness.According to the different thickness of flange and web,the component measured by the residual stress test is divided into 2 categories and 8 kinds of cross section.The components of the axial compression test are divided into 14 components according to the sectional specification and length.The sectional specification is consistent with the residual stress test.The experimental study of long column around weak axis is carried out.The finite element analysis of the integral stability of axial compression members,establishes a finite element analysis model,which takes the initial geometric imperfections and residual stresses into account.Meanwhile,the process of establishing finite element model is introduced in detail.At the same time,the finite element analysis results are compared with the test results,which verifies the accuracy and reliability of the model.Meanwhile,the finite element analysis and experimental values are compared with the theoretical values.In the study of the column curve,the integral stability coefficient of 208 components with different radius of gyration,different section sizes and lengths are calculated,through the comparison with China,the United States and Europe,three countries and regions of the steel structure design code.The selection of the type of the Q460 GJ steel welded thin H shaped member and the thick H shape column curve is suggested,and presents a design method for the application of Q460 GJ shaped steel welded H members in Engineering.The innovations of this paper are as follows:(1)Through the research of this topic,it will benefit the performance advantages of Q460 GJ steel on the component level.The performance advantages are reflected by the corresponding design parameters and serve the major domestic engineering projects.(2)By introducing the distribution patterns of residual stress obtained by our team and taking account of the factors of geometric initial imperfections,the overall stability of welded Q460 GJ steel axial compressed H-shaped members can be accurately analyzed.(3)A reasonable test scheme is designed to obtain more reasonable ultimate bearing capacity limit of Q460 GJ steel axial compression members.By means of parametric analysis,a large number of column curves are obtained,and a more rational proposal for curve selection could be given by comparing the column curves with the codes of other countries.At the same time,the performance database of GJ steel axial compression members is enriched,and In order to obtain the uncertainty of calculation model for welded Q460 GJ steel axial compressed H-shaped members based on the theory of structural reliability,the foundation of the calculation model is given.更多还原