圆孔蜂窝梁的力学性能

为了进一步推广蜂窝梁在实际中的应用,针对中国结构设计规范尚未对此结构作出规定的现状,通过ANSYS有限元分析软件,采用板壳元建立不同参数的圆孔蜂窝梁计算模型,对圆孔蜂窝梁的静力性能进行研究,探讨了跨度、开孔率、孔间距等参数对梁强度、刚度和稳定性能的影响,并将计算结果与相同截面的实腹式构件对比,给出了较为简化的实用设计公式,为圆孔蜂窝梁的进一步研究与应用提供了参考。     

扩高比对蜂窝框架抗震性能的影响

研究不同扩高比对蜂窝钢框架抗震性能的影响.以蜂窝式钢框架结构抗震性能试验为基础,利用有限元软件建立合理的有限元模型.对开孔形式相同的蜂窝梁采用不同腹板扩高比框架结构,并模拟低周反复荷载作用下的受力过程和破坏形式.得到了不同扩高比下蜂窝钢框架的滞回曲线、骨架曲线、刚度退化、延性等性能,并进行对比与分析.结果表明:开孔形式...     

支座降低蜂窝形钢梁整体稳定分析和试验

本文对徐州彭城电厂支座降低蜂窝梁的整体稳定性进行了分析，并进行了３根８．５６ｍ长蜂窝梁在均布荷载作用下的整体稳定试验，为工程实际应用提供了可靠的依据。     

蜂窝梁弹性弯扭屈曲承载力的简化计算方法研究

蜂窝梁构造复杂,对其承载力进行精确计算困难。为了研究蜂窝梁弹性弯扭屈曲承载力,在对蜂窝梁截面各特征值进行简化计算的基础上,用实腹H型钢梁的弹性弯扭屈曲临界荷载计算理论研究了蜂窝梁在不同荷载作用形式下的弹性弯扭屈曲承载力。使用ABAQUS软件对蜂窝梁的弹性弯扭屈曲承载力进行特征值屈曲分析,并与理论计算结果进行对比,验证了计算式的有效性。最后,通过分析不同因素对蜂窝梁弹性弯扭屈曲承载力的影响得出:高跨比影响最大;扩张比影响次之;距高比影响最小,可以忽略。     

简支蜂窝梁极限承载力简化设计方法

在分析均布荷载、跨中集中荷载对蜂窝梁极限承载力的影响的基础上,找出蜂窝梁的破坏规律,得出不同跨高比下,简支蜂窝梁在两种荷载情况下的极限承载力精确值。在与目前计算公式对比的基础上,提出便于工程应用的设计承载力简化计算公式。     

六边形孔折线形蜂窝梁力学性能研究

该文利用ABAQUS软件对六边形折线形蜂窝梁在荷载作用下的受力情况进行了模拟计算。通过全过程受力分析进一步了解六边形孔折线形蜂窝梁的受力表现。明确了孔型对折线形蜂窝梁承载能力的影响程度。验证了折线形蜂窝梁桥趾截面正应力计算公式适用性。     

加腋梁工程特性有限元参数分析

近年来随着加腋梁在工程中应用日趋广泛,对加腋梁的力学性能分析提出了要求。本文采用平面应力单元模拟加腋梁在承受均布荷载作用下的弹性变形和内力,通过60组模型给出了一系列加腋参数下加腋梁对应的内力和弹性变形,并对加腋后梁的弹性受力性能进行分析,给出了仅和加腋高比α、加腋长比β有关的支座弯矩系数、跨中位移系数的取值计算图表。     

爆炸荷载下预应力混凝土梁抗爆性能数值模拟

利用有限元软件LS-DYNA 对预应力混凝土梁在爆炸荷载作用下的力学性能进行数值研究。对4 组预应力混凝土梁在爆炸荷载作用下的抗爆性能进行数值模拟,研究预应力大小和混凝土强度对梁抗爆性能的影响。提取跨中最大位移、残余位移、裂缝形态、钢筋应力和支座附近混凝土剪应力,通过与相同爆炸荷载作用下无预应力混凝土梁的性能进行对比,得到预应力对钢筋混凝土梁抗爆性能的影响规律。     

梁不同扩张比蜂窝门式刚架抗震性能分析

通过设置蜂窝门式刚架梁不同扩张比,采用ABAQUS有限元软件模拟分析梁扩张比对蜂窝门式刚架整体抗震性能的影响。研究了蜂窝门式刚架在水平循环荷载作用下的破坏规律,对比分析了各个模型的滞回曲线、骨架曲线、刚度退化、延性和耗能能力。研究结果表明:蜂窝门式刚架较原实腹刚架屈服荷载提高了15.2%~33.3%,极限荷载提高了9.2%~28.5%;梁扩张比小于1.45时,扩张比越大承载力越高,扩张比超过1.45时,随扩张比越大承载力下降;扩张比在1.3~1.4范围内蜂窝门式刚架整体受力较为合理。     

钢筋混凝土圆孔梁的抗震性能及其设计方法

采用钢筋混凝土圆孔梁是一种降低高层建筑层高的有效途径。由于梁腹开孔后破坏了钢筋混凝土梁的受剪机理，尤其当孔洞设置在框架梁端附近时，在地震作用下，使高层建筑框架梁端塑性铰区域的受力性能更为复杂。为解决这类框架梁的设计问题，本文通过２４根圆孔梁及２根对比实腹梁的低周反复荷载试验和静力荷载试验，结合对国内外有关试验的研究，基本摸清了圆孔梁的静力性能及抗震性能。根据受力特征和破坏形态的机理分析，提出了圆孔梁的实用强度计算方法及有效的配筋构造措施。     

六边形孔蜂窝梁挠度的数值模拟与分析

利用有限元软件ANSYS,采用板壳单元和双线性随动模型,对六边形开孔的蜂窝梁在均布荷载作用下的挠度进行了数值模拟与分析,确定了影响其挠度的主要因素,并与实腹梁相对比,给出了适用于工程应用的挠度设计公式。     

Interaction of buckling modes in castellated steel beams

This paper investigates the behaviour of normal and high strength castellated steel beams under combined lateral torsional and distortional buckling modes. An efficient nonlinear 3D finite element model has been developed for the analysis of the beams. The initial geometric imperfection and material nonlinearities were carefully considered in the analysis. The nonlinear finite element model was verified against tests on castellated beams having different lengths and different cross-sections. Failure loads and interaction of buckling modes as well as load-lateral deflection curves of castellated steel beams were investigated in this study. An extensive parametric study was carried out using the finite element model to study the effects of the change in cross-section geometries, beam length and steel strength on the strength and buckling behaviour of castellated steel beams. The parametric study has shown that the presence of web distortional buckling causes a considerable decrease in the failure load of slender castellated steel beams. It is also shown that the use of high strength steel offers a considerable increase in the failure loads of less slender castellated steel beams. The failure loads predicted from the finite element model were compared with that predicted from Australian Standards for steel beams under lateral torsional buckling. It is shown that the Specification predictions are generally conservative for normal strength castellated steel beams failing by lateral torsional buckling, unconservative for castellated steel beams failing by web distortional buckling and quite conservative for high strength castellated steel beams failing by lateral torsional buckling.     

简支蜂窝梁整体稳定承载力有限元分析

应用通用有限元程序ANSYS得到了不同情况下简支蜂窝梁的临界荷载值,分析了各种不同参数对其整体稳定性的影响;将有限元计算结果与能量法结果进行了比较,验证了有限元结果的可行性,可为工程设计提供参考。     

蜂窝梁的设计应用

讨论了蜂窝梁在各国的应用以及相应的规范，以某工程为例，简单地介绍了该工程中应用到的蜂窝梁的设计过程，以使蜂窝梁得到更广泛地应用。     

Bracing requirements for inelastic castellated beams

Lateral-torsional buckling can be avoided by properly spaced and designed lateral bracing. Bracings are usually assumed to be elastic, and so may be characterized by their elastic stiffnesses. It is well known that an elastic lateral brace restricts partially the lateral buckling of slender beams and increases the elastic buckling moment. However, a full study of the effect of lateral braces on inelastic buckling has not been made especially for castellated beams, and it is not known whether the limiting stiffness for elastic buckling can be applied to castellated beams that buckle inelastically. This paper develops a three dimensional (3-D) finite-element model using a finite-element program and uses it to investigate the effect of elastic lateral bracing stiffness on the inelastic flexural-torsional buckling of simply supported castellated beams with an elastic lateral restraint under pure bending. It was found that for inelastic castellated beams, the effect of bracing initially is increased to some extent as the lateral unbraced length increases and then decreased until the beam behaves as an elastic beam. In other words, the effect of bracing depends not only on the stiffness of the restraint but also on the modified slenderness of the beam. Also, the results show that Winter’s simplified method to determine full brace requirements cannot be applied to inelastic castellated beams. Therefore, a general equation is proposed to determine the value of optimum stiffness in terms of the beam’s slenderness, applicable to all castellated beams under pure bending.     

蜂窝梁的稳定性能研究进展

对蜂窝梁破坏模式的研究表明，失稳是其结构性能失效的重要破坏模式。为此，在回顾蜂窝梁结构特性研究的基础上，总结归纳了蜂窝梁失稳的3种主要模式：整体弯扭失稳、梁墩屈曲、畸变屈曲。结合国内外近30多年来对蜂窝梁稳定性的试验研究成果，对影响蜂窝梁稳定性的主要因素进行分析。采用蒙特卡洛法得到纯弯简支蜂窝梁弯扭失稳临界荷载的概率分布和影响因子的敏感度。将部分具有代表性的试验成果与欧洲规范EN 1993-1-1计算结果进行对比，根据中国规范GB 50068—2001《建筑结构可靠度设计统一标准》提供的抗力分项系数，计算了不同荷载组合下蜂窝梁整体弯扭失稳临界荷载的可靠度指标，为国内规范的制订提供依据。最后，总结了当前蜂窝梁稳定性研究中存在的不足，指明了进一步研究的方向。     

蜂窝梁设计规范的比较研究

本文介绍了蜂窝梁的应用及发展，对比研究了各国有关规范和标准关于蜂窝梁的强度、刚度、稳定性等设计的理论基础及计算方法，期望能对我国尽早将蜂窝梁设计列入相关规范起参考作用。     

基于ANSYS的蜂窝梁受力性能分析

蜂窝梁作为一种经济合理的构件形式在工程中得到了广泛的研究和应用,但是关于孔洞对蜂窝梁弹塑性性能影响的研究还不够深入。利用非线性有限元分析方法对六边形孔蜂窝梁进行了弹塑性分析,研究了孔洞对蜂窝梁的应力分布、塑性区分布及挠曲变形的影响,并与实腹梁的受力性能进行了分析比较,对工程设计提出了建议。