门式刚架平齐式端板梁柱节点有限元与试验分析

对4个不同构造的门式刚架平齐式端板连接节点进行承载力试验及相应的有限元分析,以了解实际工程中该类节点的力学性能,并对节点在正负弯矩作用下的性能进行有限元分析。研究表明,节点域设置加劲肋可显著提高承载力,仅加厚梁端扳对承载力提高作用不明显,平齐式节点非线性特性出现较早。     

门式刚架轻钢结构端板连接节点承载性能的有限元分析

采用ANSYS有限元软件建立了考虑接触和螺栓预拉力的三维有限元模型,对带加劲肋的外伸式端板连接节点进行了非线性分析,讨论了端板厚度、连接形式对端板连接节点的承载力和节点刚度特性的影响,同时对现行规范的相关设计原则进行了分析和验证,并提出了一些设计建议。     

门式刚架半刚性节点的试验研究及有限元分析

门式刚架结构是目前国内外单层工业厂房及单层大跨民用建筑中应用最广泛的结构,转角节点是门式刚架的主要连接部分,其连接性能将直接影响到门式刚架结构在荷载作用下的整体行为.同时,该类节点的构造特点也决定了其刚度特征为半刚性.本文将通过数值模拟和试验方法,就不同标准的梁柱腹板高厚比、翼缘外伸宽厚比以及转角节点区高宽比的门式刚架转角半刚性节点进行系统的研究.建立了三折线弯矩-转角模型,得出了弯矩-转角关系曲线表达式.     

端板初始变形对外伸式端板连接性能的影响

针对门式刚架外伸式无肋端板连接中端板普遍存在初始变形的问题 ,采用有限元法对有初始变形的典型端板连接做了模拟分析 ,重点研究了端板初始变形对连接的内力、变形等性能的影响 ,并结合工程实际提出了设计建议     

外伸式端板螺栓连接节点的有限元分析

利用有限元ANSYS对外伸式端板螺栓连接节点受力性能进行了分析,从改变端板厚度和螺栓直径方面进行了节点受力性能研究,提出了钢框架结构设计节点时可按构造形式划分螺栓受力模型。     

变截面门式刚架端板平放试验分析

本试验对一组三个1:2的门式刚架端板平放试件加载至破坏,获取全过程应力-应变的滞回性能曲线及不同现象的破坏。通过对比分析,从而得到门式刚架端板平放受力性能,以及指出在设计时所应注意的问题。     

门式刚架轻型房屋钢结构端板连接的有限元与试验分析

结合门式刚架轻型房屋钢结构中普遍应用的端板连接方式 ,本文对梁柱节点和梁拼接节点进行了试验和有限元分析 ,对外伸式端板连接的承载力和转动刚度特性进行了研究 ,讨论了我国现行规范关于外伸式端板连接的设计方法中存在的问题 ,同时给出了改进建议 ,特别是提出了在建立钢结构节点刚度分类标准方面应该注意的问题。根据比较分析的结果 ,本文还提出了一种新的外伸式端板连接螺栓拉力分布模型及相应的设计方法 ,试验证明 ,该方法在保证安全可靠的前提下 ,能够更好地符合螺栓端板连接的实际受力状态 ,发挥螺栓和端板的承载能力     

门式刚架轻型钢结构端板连接节点性能研究与设计

针对门式刚架轻型钢结构中普遍应用的端板连接方式,介绍了工程上通常采用的端板连接形式,并采用有限元模型对连接节点进行了内力和变形分析,研究了此类节点的性能和设计计算方法,并结合工程实际提出了设计建议.     

门式刚架端板连接节点在加劲肋作用下的性能研究

目前国内端板连接计算还没有设计规范,理论方面也在探讨研究中。我国现行规程关于端板连接承载力的设计计算方法还没有考虑端板加劲肋对节点承载力的影响。采用通用有限元软件ANSYS 10.0综合考虑三重非线性的影响,同时考虑螺栓预拉力的影响,对考虑端板厚度、端板加劲肋的设置、螺栓直径、摩擦系数等参数不同的3个系列28个门式刚架梁柱节点试件进行有限元数值模拟,对连接节点的性能进行分析研究,提出设计建议以供参考。     

门式刚架转角节点加劲肋设置试验研究及有限元分析

对在门式刚架转角节点处设置斜向加劲肋和无斜向加劲肋的试件进行了试验和有限元分析,对比荷载-位移曲线,转角节点处设置斜向加劲肋的构件承载力比没有设置斜向加劲肋的构件承载力提高了约40%。研究结果表明,在转角节点处设置斜向加劲肋可以提高试件的承载力。实际工程中,当外翼缘受拉时,建议在转角节点处设置斜向加劲肋,防止结构失稳,并能有效改善结构的延性。     

Finite element analysis on the static behaviour of wide-type large capacity end-plate connections

Compared to the traditional two-column-bolt layout, the wide-type end-plate connections with four bolts in a row could resist a greater moment. In this paper, a detailed verified finite element model is employed to analyse the static behaviour of six wide-type end-plate connections, where parameters such as the end-plate thickness, bolt layout, extended or flushed end plate and the geometry of the stiffener are covered. The simulation results demonstrate that (1) in the elastic range, the transferred tension force of the bolts far from the beam web is about 0.33～0.67 times that of the closer ones; (2) the shear force in the bolts is tiny; (3) at the ultimate state the bolts located far from the beam flange have a significant contribution to the loading capacity of the connection while it shows little contribution in the elastic state. In addition, a yield-line model of the tension part of the end plate is proposed.     

端板连接节点对门式刚架整体性能的影响分析

传统钢结构设计中将高强螺栓端板连接作为刚性节点,而实际情况下这种连接形式与计算结果有差异.采用有限元方法针对8种不同计算跨度的轻型门式刚架建立了三维整体有限元模型,分析了高强螺栓端板连接的节点刚度对门式刚架内力和位移的影响.计算结果表明,高强螺栓端板连接是一种半刚性连接形式,节点刚度对门式刚架整体结构的内力和变形将产生较大影响,在门式刚架的分析和设计中,应考虑节点半刚性的实际影响.     

超大承载力端板连接节点有限元分析和设计方法

超大承载力端板连接节点能够提供比普通构造的端板连接节点和大承载力端板连接节点更大的抗弯承载力,可以应用于大跨或重载钢结构中。由于超大承载力端板连接节点的螺栓拉力分布不均匀、端板受力状态复杂,现有的端板连接节点设计方法不能直接应用。此文建立超大承载力端板连接节点的有限元模型,通过已有试验验证模型的可靠性|利用有限元模型分析单调荷载下超大承载力端板连接节点的受力性能,提出弯矩作用下受拉区端板的屈服线模型和受拉区螺栓承担拉力的分布模型。在所提模型的基础上基于我国规范提出超大承载力端板连接节点的抗弯承载力设计方法。比较所提设计方法得到的节点抗弯承载力设计值与有限元得到的屈服承载力,在我国规范规定的高强度螺栓受拉极限状态条件下所提方法得到的设计结果偏于安全。     

门式刚架梁柱端板连接节点设计理论研究

参照欧美钢结构计算手册,并依据端板变形协调条件,推导出端板连接节点螺栓撬力及节点承载力计算公式,并得出了一些有益的结论,从而为端板连接节点的进一步研究和分析提供了理论基础。     

温度变化对某门式刚架影响的有限元分析

利用有限元方法 ,分析了 3 0℃和 40℃的温度变化对某车间门式刚架的力学影响 ,证明该结构在设计时应充分考虑温度荷载的影响 ,并对类似工程提出了建议     

半刚性端板连接节点性能的非线性有限元分析

采用三维接触单元来模拟端板与柱翼缘的接触面,预应力单元来模拟螺栓的预拉力,对半刚性端板连接节点性能进行了非线性有限元分析。计算结果的比较分析表明,节点域加劲肋、端板加劲肋、端板厚度、螺栓预拉力、应力集中等因素对半刚性端板连接节点域的受力性能均有较大影响。建议在设计中采取相应构造措施,考虑端板节点半刚性的不利影响。     

网壳结构鼓型节点弹塑性分析及模型试验

铸钢节点是大跨空间结构广泛采用的一种节点型式,通过对重庆奥林匹克体育中心体育场网壳结构鼓型铸钢节点有限元弹塑性分析,得到铸钢节点应力、应变分布情况.通过鼓型铸钢节点结构的实体试验,得到各测点应力测试值.结合理论分析和实体试验,指出铸钢节点应力分布规律及特点,对鼓型铸钢节点的承载安全性做出评价,为鼓型铸钢节点设计提出几点建议.     

Experimental and numerical study on a full scale apex connection of cold-formed steel portal frames

In this paper, experimental and theoretical studies performed on apex connection of an industrial portal frame constructed with cold-formed back-to-back double sigma profile rafters are presented. By those experiments performed, local buckling behavior of the apex plate and load–displacement behavior of the system were investigated under monotonic vertical loading. This investigation was conducted for conditions that the gap between rafter ends at the apex plate are 90, 180, 360, and 450 mm and apex plate is unstiffened/stiffened. Experimental results for the model with 360 mm gap were compared to those of nonlinear quasi-static finite element analyses performed using a finite element software and a good agreement between those results was observed. The connection׳s behavior is controlled by the apex plate. No significant damage occurred on the profiles after the tests. According to the results, it is sufficient to increase the gap between rafter ends up to not higher than 360 mm in order to maximize the general load carrying capacity of the system and the stability of out of plane local buckling behavior of the apex plate. Furthermore, although stiffener plate significantly restricted local buckling of apex plate, no remarkable effect of this enhancement was observed on the flexural capacity of the system.     

端板厚度对梁柱外伸端板节点滞回性能的影响

对钢框架梁柱外伸端板连接节点的端板采用三种不同厚度进行有限元分析,得到其滞回性能曲线,分析了端板厚度对节点抗震性能的影响规律,指出端板厚度不宜过薄,边薄将降低承载力,但也不宜过厚,过厚将使延性变差。     

Influence of initial imperfection on the behaviour of extended bolted end-plate connections for portal frames

Initial imperfection in bolted end-plate connections is mainly induced by residual deformation of welding. Three typical initial imperfections, namely V-shape, C-shape and W-shape are identified in terms of the geometrical imperfection shapes for extended bolted end-plate connections based on a field study. Seven specimens of extended bolted end-plate connection, among which six specimens with V-shape initial imperfection and one without imperfection in the end-plates were tested, and the influence of the initial imperfection of the end-plate on the behaviour of the connections was investigated. Test results show that initial rotation stiffness of extended bolted end-plate joints decreases with increase of initial imperfection in the end-plate, however, the strength of the end-plate joints is only affected slightly by the imperfection. Besides, the thicker the end-plate is, the more reduction in the initial rotation stiffness relatively. Further parametric study on 14 extended bolted end-plate connections with three typical shapes of imperfections were conducted based on the finite element analysis. Among the three types of initial imperfection, the V-shape has the least influence, and the C-shape has the biggest influence on the initial rotation stiffness of the extended bolted end-plate joints. For initial geometrical imperfection in a V-shape, its influence on behaviour of extended bolted end-plate connections is negligible as far as the imperfection is limited to the criterion, giving H/300. The influence of initial imperfection in a W-shape on rotation stiffness should be acceptable if the initial imperfection is limited to the criterion. In the case of a C-shape initial imperfection in the end-plate, its influence on the rotation stiffness would be substantial; even it satisfies the requirement of the imperfection limit. The results of the study should be applicable to the bolted end-plate connections, whether flushed or extended end-plate beam to column joints in structural frames.