正弦波纹腹板H型钢梁腹板几何参数的优化研究

发布时间：2018-05-27 05:02

本文选题：正弦波纹腹板 + 波纹腹板H型钢梁　；参考：《西南石油大学》2016年硕士论文

【摘要】：目前,H型钢在我国处于举足轻重的位置,而在钢结构建筑中,H型钢主要应用于门式刚架的梁、柱和吊车梁等处。但普通平腹板H型钢的高厚比受到限制,需要通过设置加劲肋等措施进而提高其稳定性能,这就大大增加了结构的自重和工程造价,因此,基于普通平腹板H型钢存在着诸多问题,波纹腹板H型钢的出现使得一系列问题迎刃而解。波纹腹板H型钢梁以较薄厚度的波纹钢板作为腹板,不需要加劲肋的协助便可获得较好的剪切屈曲强度和刚度,大幅度地降低了材料用量,体现出显著地经济效益。基于波纹钢腹板的优越性,近年来国内外学者已对该结构形式进行了一系列的研究,并得到有价值的结论。本文主要以正弦波纹腹板H型钢梁为研究对象,运用ABAQUS有限元软件对其剪切屈曲性能进行详尽地研究,并与相同条件下的三角形波纹、矩形波纹腹板形式进行抗剪切屈曲能力的对比；同时也对正弦波纹腹板的几何参数进行优化,以得到能够降低材料用量的几何参数值或取值区间。主要的研究内容如下：(1)本文对波纹钢腹板的屈曲理论进行详尽地阐述,包括抗弯屈曲理论、抗扭屈曲理论以及抗剪屈曲理论,其中重点对剪切屈曲的三种屈曲模式进行介绍。在阐述波纹钢腹板抗剪屈曲理论的过程中,针对本文的研究对象正弦波纹腹板H型钢梁,并依据梯形波纹形式下屈曲强度的计算公式,本文推导出适用于正弦波纹腹板的整体屈曲强度τcr,g计算公式、局部屈曲强度τcr,l计算公式,以及后续优化研究的约束条件即控制剪切应力τ的计算公式；(2)本文应用ABAQUS有限元软件对简支条件下的正弦波纹腹板H型钢梁进行弹性屈曲分析,重点研究了H型钢梁跨度L和正弦波纹腹板几何参数,包括腹板厚度t、腹板高度h、波长λ*、波幅H*对H型钢梁屈曲性能的影响,得到了大量的临界屈曲荷载值。随后运用Origin绘图软件绘制出尺寸参数与临界屈曲荷载之间的变化关系曲线,最终总结出各个尺寸参数变化时临界屈曲荷载的变化规律及结论。同时,本文还对比分析了相同条件下三角形波纹、矩形波纹与正弦波纹抗剪切屈曲能力的异同点,为今后多种波纹形式的全面发展提供理论依据；(3)本文运用MATLAB优化工具箱中的基本函数fmincon函数对正弦波纹腹板的几何参数进行优化分析和处理,重点对研究涉及的约束非线性问题和如何用MATLAB编写约束函数M文件、目标函数及其他约束条件作详细地叙述。通过MATLAB软件的优化处理,可以得到最优解和目标函数的最优值。结合腹板几何参数对临界屈曲荷载的影响规律,最终能够获得满足正弦波纹腹板H型钢梁屈曲能力且节约材料用量的几何参数取值或取值区间。
[Abstract]:At present, H-shaped steel plays an important role in our country, while in steel structure building, H-shaped steel is mainly used in beam, column and crane beam of portal frame. However, the ratio of height to thickness of ordinary flat web H-section steel is limited, so it is necessary to improve the stability of H-section steel by means of stiffening rib, which greatly increases the weight of the structure and the engineering cost. Based on the common flat web H section steel, there are many problems, and the emergence of corrugated web H section steel makes a series of problems solved. The corrugated web H-type steel beam takes a thin corrugated steel plate as the web plate, and the shear buckling strength and stiffness can be obtained without the help of stiffening ribs. The material consumption is greatly reduced and the remarkable economic benefit is shown. Based on the superiority of corrugated steel web, scholars at home and abroad have carried out a series of research on the structure in recent years, and got valuable conclusions. In this paper, the shear buckling behavior of sinusoidal web H-beam is studied in detail by using ABAQUS finite element software, and it is compared with triangular corrugation under the same conditions. The shear buckling ability of rectangular corrugated web is compared, and the geometric parameters of sinusoidal web are optimized to obtain the geometric parameter or interval which can reduce the amount of material. The main research contents are as follows: (1) in this paper, the buckling theory of corrugated steel web plate is elaborated in detail, including bending buckling theory, torsional buckling theory and shear buckling theory, in which three buckling modes of shear buckling are introduced. In the course of expounding the shear buckling theory of corrugated steel web, aiming at the research object of this paper, the H-shaped steel beam with sinusoidal webs is calculated according to the formula of buckling strength under the form of trapezoidal ripple. In this paper, the formulas for calculating global buckling strength 蟿 crg and local buckling strength 蟿 crl for sinusoidal web are derived. In this paper, ABAQUS finite element software is used to analyze the elastic buckling of sinusoidal webs H-shaped steel beams under simply supported conditions. The effects of span L and sine ripple web geometry parameters, including web thickness, web height, wavelength 位 and amplitude H *, on the buckling behavior of H-type steel beams are studied, and a large number of critical buckling load values are obtained. Then the curve between the dimension parameter and the critical buckling load is drawn by using the Origin drawing software. Finally, the variation law and conclusion of the critical buckling load with the change of the dimension parameter are summarized. At the same time, the similarities and differences of the shear buckling resistance of triangular, rectangular and sinusoidal ripples under the same conditions are also analyzed. In this paper, the basic function fmincon function in MATLAB optimization toolbox is used to optimize the geometric parameters of sinusoidal web plate. The problem of constraint nonlinearity involved in the study and how to write the constraint function M file, objective function and other constraint conditions with MATLAB are described in detail. The optimal solution and the optimal value of the objective function can be obtained by the optimization of MATLAB software. Combined with the influence of web geometry parameters on critical buckling load, the geometric parameters or interval of critical buckling load can be obtained to satisfy the buckling capacity of sinusoidal web H-shaped steel beams and to save material consumption.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TU392.1

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