非均匀受压矩形钢管混凝土局部弹性屈曲分析

应用不同的特征函数描述了矩形板在非均匀压力作用下的屈曲形态,解决了采用三角级数为屈曲函数模拟非均匀受压荷载作用下单侧表面约束矩形板件屈曲模态的不对称问题;通过伽辽金法建立屈曲控制方程组,分析了非均匀荷载作用对矩形钢管混凝土构件局部弹性屈曲性能的影响。结果表明:钢管屈曲系数随着不均匀荷载梯度α增加而增大,纯弯作用下（α=2）的板件弹性屈曲荷载特征值约为轴压作用下的6倍;钢板的宽厚比限值随不均匀加载梯度α的增大而增加;非均匀荷载作用下非加载边固支约束板件的屈曲系数明显大于简支约束的板件。     

两端连接偏心支撑钢板剪力墙的弹性屈曲研究

结合支撑和钢板剪力墙的特点,提出了两端连接偏心支撑钢板剪力墙的结构形式,采用ANSYS有限元软件进行了弹性屈曲分析,重点研究了内填板的高厚比、宽高比、柱弹性刚度对弹性屈曲系数和屈曲荷载的影响。结果表明,支撑能够起到显著提高屈曲荷载的作用。高厚比和宽高比是影响两端连接偏心支撑的钢板墙的弹性屈曲荷载的主要因素。为进一步研究两端连接偏心支撑钢板剪力墙的多道抗震设防奠定了理论基础。     

剪压荷载作用下钢板剪力墙弹性屈曲性能研究

国内外对钢板剪力墙的研究较少考虑竖向荷载的影响,这与工程实际不符。为准确估算钢板剪力墙承受竖向荷载后的弹性屈曲性能,对四边简支,两侧边固支、上下边简支和四边固支矩形钢板剪力墙在剪压作用下的弹性稳定性能进行有限元分析。根据有限元计算结果,修正不同边界条件钢板剪力墙剪压荷载下的相关屈曲计算公式,与有限元结果比较表明,修正后...     

组合钢板墙混凝土板厚度及剪力连接件间距的确定

组合钢板剪力墙是指由钢板、混凝土板及边缘框架通过连接构件组成的组合构件,钢板和混凝土板通过剪力连接件连接。从弹性板屈曲理论出发,针对钢板与混凝土板相互作用情况不同将组合钢板墙分成组合型墙和防屈曲型墙,研究钢板承担水平荷载、混凝土板不直接参与受力情况下组合钢板墙混凝土板厚度和剪力连接件间距的设计。对比讨论了混凝土板厚度计算公式的适用性,并给出建议以形成正在编制的广东省标准《钢结构设计技术规程》的有关章节。     

两侧边开缝钢板剪力墙弹性屈曲分析

提出一种新型的两侧边开缝的钢板剪力墙,并对其两侧边有无加劲肋的两种结构形式进行有限元弹性屈曲分析,分别讨论其临界屈曲荷载和屈曲模态.对两侧无加劲肋的钢板剪力墙,给出用于其设计的屈曲系数公式,对两侧有加劲肋的钢板剪力墙给出具有参考价值的设计建议.     

钢筋混凝土矩形薄板在弹性地基上的热屈曲

基于板的小挠度理论,考虑混凝土材料的非线性,推导了弹性地基上钢筋混凝土矩形薄板在热载作用下的平衡方程和稳定方程,给出了四边简支钢筋混凝土矩形薄板在均匀温度变化时临界屈曲温度变化的封闭解,讨论了板的材料常数、长宽比、相对厚度和基床系数等对临界屈曲温度变化的影响,从而为工程结构中弹性地基上钢筋混凝土矩形薄板的临界屈曲温度的计算提供了理论计算依据。     

两边连接交叉加劲钢板剪力墙弹性屈曲分析

采用ANSYS有限元软件对两边连接交叉加劲钢板剪力墙进行了弹性屈曲分析,重点研究了加劲肋与墙板的刚度比、墙板高厚比、边长比以及加劲肋宽厚比对弹性屈曲系数的影响,并将分析结果与十字加劲板进行了比较.研究表明,交叉加劲肋能够显著提高钢板剪力墙的弹性屈曲荷载,其远大于十字加劲肋;随着墙板边长比和高厚比的增大,屈曲系数趋于减小;而较小的加劲肋宽厚比能使墙板获得较大的屈曲系数;最后给出了两边连接交叉加劲板弹性屈曲系数的计算公式.     

交叉加劲钢板剪力墙弹性屈曲研究

用有限元方法对交叉加劲钢板剪力墙的弹性屈曲性能进行了研究,重点研究了加劲肋与墙板的刚度比、墙板高厚比、边长比以及加劲肋宽厚比等对弹性屈曲系数k的影响,同时与十字加劲板的抗剪屈曲性能进行了对比。研究结果表明,设置交叉加劲肋能显著提高钢板剪力墙的弹性屈曲荷载;屈曲系数k随着墙板边长比、高厚比以及加劲肋宽厚比的增大而趋于减小;本文给出的交叉加劲板弹性屈曲系数k的计算公式与有限元法的结果较吻合。     

全加劲两侧开缝钢板剪力墙弹性屈曲研究

采用有限元方法对全加劲两侧开缝钢板剪力墙在面内水平荷载作用下的弹性屈曲临界荷载、屈曲模态进行了研究。对影响其弹性屈曲性能的参数进行了分析,包括两侧和中部加劲肋与墙板的刚度比、两侧和中部加劲肋宽厚比以及墙板高厚比和边长比。给出了全加劲两侧开缝钢板剪力墙加劲肋的弹性屈曲设计参考公式,为开缝钢板剪力墙的应用提供依据。     

矩形钢管混凝土壁板的屈曲后强度

为研究矩形钢管混凝土壁板的屈曲后强度,根据平板的弹塑性屈曲理论并考虑残余应力的影响,确定了板件发生塑性屈曲、弹塑性屈曲和弹性屈曲的正则化界限宽厚比。采用试验验证的有限元模型进行了宽厚比为20～150、钢材屈服强度为275～960 MPa的矩形钢管混凝土壁板局部屈曲分析,以界限宽厚比为控制点,根据有限元结果拟合出了矩形钢管混凝土壁板的有效宽度计算式。研究结果表明：弹性屈曲板件的屈曲后强度提高程度显著高于弹塑性屈曲板件;屈曲后强度的提高程度与钢材屈服强度无明显相关性;与无面外约束钢板相比,混凝土的单侧约束作用可使板件的屈曲后强度普遍提高约50%;提出的矩形钢管混凝土壁板的正则化界限宽厚比和有效宽度计算式与试验结果吻合较好,有效宽度试验值比所提公式计算值平均增大7.2%,标准差为0.091。     

Local buckling of steel plates in rectangular CFT columns with binding bars

This paper presents a theoretical study on the elastic local buckling of steel plates in rectangular concrete-filled steel tubular (CFT) columns with binding bars under axial compression. It is assumed that the unloaded edges of the steel plate are elastically restrained against rotation, whereas the loaded edges are clamped. Based on the energy method, the formulas for elastic local buckling strength of the steel plate in rectangular CFT columns under axial compression are derived, which are calibrated with the experimental results. Then the formulas are employed to study the elastic local buckling of steel plates in rectangular CFT columns with binding bars under axial compression. It is shown that the binding bars can increase the local buckling coefficient, which results in improvement of the capacity of the steel plate to resist local buckling. Finally, appropriate spacing of binding bars, appropriate limitation for aspect ratio and corresponding appropriate limitation for width-thickness ratio are suggested for rectangular CFT columns with binding bars under axial compression.     

Local buckling of steel plates in concrete-filled thin-walled steel tubular beam-columns

The availability of high strength steels and concrete leads to the use of thin steel plates in concrete-filled steel tubular beam-columns. However, the use of thin steel plates in composite beam-columns gives a rise to local buckling that would appreciably reduce the strength and ductility performance of the members. This paper studies the critical local and post-local buckling behavior of steel plates in concrete-filled thin-walled steel tubular beam-columns by using the finite element analysis method. Geometric and material nonlinear analyses are performed to investigate the critical local and post-local buckling strengths of steel plates under compression and in-plane bending. Initial geometric imperfections and residual stresses presented in steel plates, material yielding and strain hardening are taken into account in the nonlinear analysis. Based on the results obtained from the nonlinear finite element analyses, a set of design formulas are proposed for determining the critical local buckling and ultimate strengths of steel plates in concrete-filled steel tubular beam-columns. In addition, effective width formulas are developed for the ultimate strength design of clamped steel plates under non-uniform compression. The accuracy of the proposed design formulas is established by comparisons with available solutions. The proposed design formulas can be used directly in the design of composite beam-columns and adopted in the advanced analysis of concrete-filled thin-walled steel tubular beam-columns to account for local buckling effects.     

C型钢板剪力墙截面特性分析

C型钢板剪力墙以其独特的构造,能较好地适应高层建筑的功能和结构受力要求.对其特殊截面的剪切中心进行理论分析,采用近似法和精确法两种方式加以阐述;对多块钢板组成的构件的板件局部稳定性能进行有限元分析,分析结果与四边简支板件的临界值相符,可确定板组约束系数.通过有限元分析板件的局部屈曲,可更清楚地认识板件的屈曲特性.     

PBL加劲型矩形钢管混凝土轴压柱局部屈曲性能分析

为研究开孔钢板连接件（PBL）加劲肋对矩形钢管混凝土轴压柱局部屈曲性能的影响,用能量法推导钢管屈曲系数计算公式,引入PBL和加劲肋相对刚度计算式并分析二者对屈曲模式的相互作用关系,讨论了PBL加劲型钢管的极限屈曲模式及其极限屈曲系数、最大相对宽厚比限值。结果表明:PBL加劲肋可明显改善钢管局部稳定性,钢管屈曲系数k随着PBL加劲肋刚度增加而增大,直至达到极限屈曲系数42.68;PBL连接件可减小板件纵向屈曲的波长,而加劲肋的影响作用与之相反;设置PBL加劲肋后,钢管的最大相对宽厚比限值可达184,并且板件屈曲后强度随宽厚比的变化曲线下降趋势减缓,强度值随着PBL刚度增加而逐渐提高。     

纵向变厚度钢板焊接工字形截面受压短柱的局部稳定试验研究

纵向变厚度(LP)钢板是一种沿轧制方向具有不同厚度钢板的钢材,可用于优化结构的力学性能和提高材料利用率。为研究其局部稳定性能,设计了6根LP翼缘焊接工字形截面短柱,6根LP腹板焊接工字形截面短柱和4根传统等厚度焊接工字形截面短柱,并进行了轴向受压试验。试验研究中确定板临界屈曲荷载的两个主要屈曲准则,同时分析了破坏模式、荷载-侧向变形曲线、荷载-应变曲线和极限荷载,研究LP短柱的局部屈曲行为,得到试件更容易在LP钢板的薄端发生屈曲破坏。将试验结果与现有等厚度板设计规范计算结果进行比较可得,现有等厚度板的设计规范预测腹板变厚度短柱的极限荷载偏于危险,而对于翼缘变厚度短柱欧规EN 1993-1-5能较为准确预测,但需要进一步的数值模拟去验证,从而进一步提出修正公式或者修正系数来指导设计。     

Finite element analysis of local buckling behavior of steel plates in concrete-filled double steel plate composite shear walls

采用ABAQUS有限元软件对双钢板-混凝土组合剪力墙中外包钢板的局部屈曲行为进行了有限元模拟,分析外包钢板在轴压作用下的局部屈曲和屈曲后的受力性能。共开展了15个模型的有限元分析,模型的变化参数包括钢板的宽厚比和对拉钢筋的列数。分析结果表明：对于列间距和行间距相同的对拉钢筋布置方案,钢板局部屈曲始终发生在相邻两对拉钢筋之间;钢板发生屈曲后,与屈曲位置相邻的对拉钢筋承受较大的拉力,且对拉钢筋拉力随着对拉钢筋间距的减小而增大;增加对拉钢筋列数和减小钢板宽厚比可有效改善外包钢板的局部稳定性能,提高钢板的承载能力和变形能力;相比点约束,线约束对钢板局部屈曲的约束更为有效;无对拉钢筋模型、单列对拉钢筋模型和双列对拉钢筋模型达到屈服强度（345MPa）所需的最小宽厚比分别为25、30和37.5。     

Seismic performance of corrugated steel plate concrete composite shear walls

In this paper, composite shear walls with different encased steel plates (flat, horizontal corrugated, and vertical corrugated) were tested and simulated by Abaqus to investigate the seismic behavior of corrugated steel plate concrete composite shear walls (SPCSWs). The failure characteristics, deformation and energy dissipation capacity, and stiffness and bearing capacity of the structures under low‐frequency cyclic load were analyzed, and indexes of the seismic performance were obtained. The formulas of the shear‐bearing capacity of steel plate concrete composite shear walls are suggested, and the shear‐sharing ratio of each member is obtained. According to the obtained results, corrugated steel plates can bond with concrete well, and the bearing capacity of the vertical corrugated SPCSW are higher than that of the horizontal corrugated SPCSW. Compared with flat SPCSW, corrugated SPCSW has higher initial stiffness and lateral stiffness, better ductility and energy dissipation ability, and the degradation of bearing capacity and stiffness is slower. The shear‐sharing ratio of a steel plate is larger than that of reinforced concrete in the flat SPCSW and the vertical corrugated SPCSW, the shear force shared by steel plate and reinforced concrete in horizontal corrugated SPCSW is basically the same.     

受压波纹板组局部相关屈曲特性研究

拱型波纹钢屋盖结构是一种典型的冷弯薄壁结构,其波纹截面板组的宽厚比远远超过有关规范宽厚比限值的上限要求,结构的极限承载能力既取决于其整体稳定承载能力也取决于其局部相关屈曲承载能力。本文根据拱型波纹钢屋盖结构的成型特点和受力特性,建立了波纹槽形截面板组局部相关屈曲分析的有限元模型,对不同宽厚比的受压波纹槽形截面板组的局部相关屈曲特性进行了理论计算,并与同形状同尺寸平板槽形截面板组的屈曲特性进行了比较分析。研究结果表明,如同平板板组一样,波纹板组也可能发生局部相关屈曲,但其板组屈曲半波长要受制于小波纹的几何尺寸,即屈曲半波应位于波形构造的波节点之间或波峰、波谷之间,而平板槽形截面板组的屈曲波长则可以自由调节,这点与平板板组的屈曲特性存在明显的差异。并且波纹的存在对板组屈曲性能有显著提高。理论研究与相应的试验研究符合很好。     

Nonlinear analysis of concrete-filled thin-walled steel box columns with local buckling effects

Local buckling of steel plates reduces the ultimate loads of concrete-filled thin-walled steel box columns under axial compression. The effects of local buckling have not been considered in advanced analysis methods that lead to the overestimates of the ultimate loads of composite columns and frames. This paper presents a nonlinear fiber element analysis method for predicting the ultimate strengths and behavior of short concrete-filled thin-walled steel box columns with local buckling effects. The fiber element method considers nonlinear constitutive models for confined concrete and structural steel. Effective width formulas for steel plates with geometric imperfections and residual stresses are incorporated in the fiber element analysis program to account for local buckling effects. The progressive local and post-local buckling is simulated by gradually redistributing the normal stresses within the steel plates. Two performance indices are proposed for evaluating the section and ductility performance of concrete-filled steel box columns. The computational technique developed is used to investigate the effects of the width-to-thickness ratios and concrete compressive strengths on the ultimate strength and ductility of concrete-filled steel box columns. It is demonstrated that the nonlinear fiber element method developed predicts well the ultimate loads and behavior of concrete-filled thin-walled steel box columns and can be implemented in advanced analysis programs for the nonlinear analysis of composite frames.     

两侧边开缝钢板剪力墙弹性屈曲分析

提出一种新型的两侧边开缝的钢板剪力墙,并对其两侧边有无加劲肋的两种结构形式进行有限元弹性屈曲分析,分别讨论其临界屈曲荷栽和屈曲模态。对两侧无加劲肋的钢板剪力墙,给出用于其设计的屈曲系数公式,对两侧有加劲肋的钢板剪力墙给出具有参考价值的设计建议。