高强钢焊接工字梁整体稳定和局部稳定性能分析

发布时间：2018-05-12 11:21

本文选题：高强钢 + 残余应力　；参考：《天津大学》2014年硕士论文

【摘要】：高强钢(屈服强度不低于460MPa)已经在诸多建筑结构和桥梁结构中得到成功应用,由于在材料力学性能、加工工艺和初始缺陷等方面存在差别,高强钢焊接工字梁的稳定性能与普通强度钢材构件会有不同。国内针对高强钢焊接工字梁整体和局部稳定性能的相关研究工作很少,并无专门的设计规范指导高强钢焊接工字梁的设计计算。本文通过分析高强钢焊接工字梁的整体稳定和局部稳定性能,修正了相关计算式。主要完成的工作以及所得结论如下:(1)根据通用的初始几何缺陷处理方法和现有适用于高强钢的残余应力分布模型,建立了引入初始几何缺陷和残余应力的有限元模型。通过参数分析,研究了初始几何缺陷、截面残余应力、钢材强度等级、截面高宽比(上下翼缘中面距离与受压翼缘宽度比值)、荷载类型和截面形式对高强钢焊接工字梁整体稳定性能的影响。(2)运用非线性屈曲分析方法得到不同钢材强度等级工字梁的整体稳定承载力,给出了整体稳定系数计算式中指数n的计算式,并建议了高强钢焊接工字梁整体稳定系数计算式,为高强钢焊接工字梁的设计计算提供参考。(3)研究了4种强度等级高强钢焊接工字梁在集中荷载和均布荷载共同作用下的整体稳定承载力,根据钢材强度等级、截面高宽比和长细比对整体稳定承载力的影响规律,给出了集中荷载和均布荷载作用下高强钢焊接工字梁整体稳定承载力的计算式。(4)通过对高强钢焊接工字梁抗剪极限承载力进行有限元分析,考虑翼缘和腹板厚度比值对抗剪极限承载力的影响,在已有基础上建议了高强钢焊接工字梁的抗剪极限承载力计算式。(5)通过分析设置加劲肋腹板区格的局部稳定性能,对《钢结构设计规范》GB50017-2003有关配置加劲肋腹板区格局部稳定的计算公式提出了修正建议。
[Abstract]:High strength steel (yield strength is no less than 460 MPA) has been successfully applied in many building structures and bridge structures, due to the differences in material mechanical properties, processing technology and initial defects, etc. The stability of welded I-beam of high strength steel will be different from that of normal strength steel member. There are few researches on the integral and local stability of welded I-beam of high-strength steel in China, and there is no special design criterion to guide the design and calculation of I-beam welded with high-strength steel. By analyzing the overall and local stability of welded I-beam of high strength steel, the correlation formula is modified. The main work and conclusions are as follows: (1) based on the general initial geometric defect treatment method and the existing residual stress distribution model suitable for high strength steel, the finite element model with initial geometric defect and residual stress is established. Through the parameter analysis, the initial geometric defects, the residual stress of the section, the strength grade of the steel are studied. Section aspect ratio (ratio of upper and lower flange midplane distance to compression flange width, influence of load type and section form on the overall stability of welded I-beam of high-strength steel.) nonlinear buckling analysis method is used to obtain the strength of different steels. The overall stable bearing capacity of the I-shaped beam of degree grade, The calculation formula of exponent n in the formula of integral stability coefficient is given, and the formula of integral stability coefficient of welded I-beam with high strength steel is suggested. For the design and calculation of welded I-beam of high-strength steel, this paper studies the overall stable bearing capacity of four kinds of strength grade I-beam welded I-beam under the combined action of concentrated load and uniform load, according to the grade of steel strength, The effect of aspect ratio and aspect ratio on overall stability bearing capacity, The calculation formula of overall stable bearing capacity of welded I-beam with high strength steel under concentrated load and uniform load is given. The finite element analysis of ultimate shear capacity of welded I-beam with high-strength steel is carried out. Considering the influence of the ratio of flange to web thickness on the ultimate shear capacity, the calculation formula of shear ultimate bearing capacity of welded I-beam with high strength steel is suggested on the basis of which the local stability of the lattice with stiffened rib web is analyzed. The formula for calculating the stability of the configuration of stiffened ribbed webs in GB50017-2003 is put forward in this paper.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU392.1

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