CFRP加固损伤钢梁有限元分析

研究了碳纤维复合材料粘贴损伤H型钢梁翼缘表面用于结构补强与加固的技术特点,对不同层数CFRP布加固受弯钢梁进行有限元分析。得到了加固前后的荷载-应变曲线和荷载-挠度曲线,分析CFRP用量对钢梁的破坏模式、屈服和极限荷载、刚度的影响。结果表明,加固钢梁屈服、极限荷载和刚度有不同程度的提高,随着加固层数的增加对结构极限状态的影响要高于对屈服状态的影响。     

焊接钢梁残余应力有限元分析

采用通用有限元软件ANSYS模拟分析焊接工字梁的焊接过程,对焊接残余应力场进行数值模拟并进行有限元分析,从而得到焊接钢梁残余应力的大小及分布规律,以便设计人员在进行相关焊缝设计时对残余应力的大小进行估算,为工程实践应用提供一定的指导。     

工字钢与波折腹板H型钢梁的有限元分析

本文采用有限元的分析方法,分别建立了实腹式工字钢梁和波折腹板H型钢梁的有限元模型。通过有限元分析对比,说明了普通工字钢梁与波折腹板H型钢梁的承载力、变形曲线的差异。分析结果表明,在钢梁上翼缘(受压区翼缘)无可靠约束时,盲目采用波折腹板H型钢梁可能会带来一定的安全隐患,在实际工程设计时应予以注意。     

冷弯型钢梁受力特性有限元分析

为了准确的研究冷弯型钢的力学性能以及各种截面的型钢对其力学性能的影响,主要针对目前国内使用最广泛的C型钢,Z型钢进行了分析,采用有限元软件模拟冷弯型钢梁在外荷载作用下的综合力学性能进行分析,给出了截面优化和提高的方案。     

点蚀钢梁承载力试验与有限元分析

为研究点蚀对钢梁极限承载力的影响,采用机械加工的方法模拟点蚀锈坑,对6根点蚀钢梁进行极限承载力试验,并进行有限元分析。根据试验和有限元数据,分析极限承载力和钢梁应力与锈蚀程度的关系。结果表明,所采用的有限元法可以较好地模拟点蚀钢梁受力性能;钢梁极限承载力随点蚀体积损伤(DOPV)的增大而下降;蚀坑深度是影响钢梁极限承载力的关键因素。     

折线形腹板钢梁静力非线性有限元分析

把工字形钢梁腹板加工成折板,是提高腹板抗屈曲能力的一种途径,考虑几何非线性和材料非线性,对折线形腹板钢梁和设置腹板加劲肋的钢梁进行了有限元分析,研究了折线形腹板钢梁的受力性能及钢梁应力和挠度的发展过程.研究表明,折线形腹板相邻板件互为支承,明显提高了腹板屈曲承载力,但屈曲后强度的提高不如设置加劲肋的腹板,钢梁有限元分析结果和实测值比较吻合.     

持荷加固钢梁的有限元研究

对荷载作用下采用焊接钢板加固的W型钢梁的性能和承载力进行有限元研究。通过6个荷载作用下的焊接钢板加固的钢梁试验验证有限元模型。采用该模型对加固梁,焊接时预载的大小,未加固梁的初始缺陷等几个主要参数的影响进行分析。数值分析结果表明:加固时预载大小的增加导致加固梁侧扭屈曲破坏极限承载力降低,与每个翼缘都用焊接钢板相比,只在受拉翼缘焊接钢板,承载力降低更显著。研究也显示,未加固梁的初始缺陷变化影响了加固梁的极限承载力。当预载的大小及初始缺陷的影响达到临界状态时,梁发生屈服破坏。     

铁路钢梁桥检查车三维有限元分析

应用SUPERSAP程序中的BEDIT梁工具箱对铁路钢梁桥检查车的主要受力杆件——内桁架梁和外桁架梁分别进行了三维有限元分析，然后通过虚拟梁单元将其组装进行总体计算。     

钢管混凝土柱—钢梁节点的有限元分析

文中借助有限元软件ABAQUS对往复加载下4个钢管混凝土柱—钢梁节点进行了有限元分析,结果表明:有限元模型计算获得的的试件破坏形态、刚度退化、峰值承载力、滞回环面积均基本符合实验结果,计算的峰值承载力、最外圈滞回环面积与试验相对误差在20％以内,证明了模型的有效性,为组合结构节点研究提高参考.     

加载点位置变化对狗骨式钢梁影响分析

文章应用ANSYS有限元分析软件,对狗骨式钢梁进行非线性结构分析。通过7个不同的加载点位置条件下狗骨式钢梁变形情况的分析,总结出一系列加载点位置的变化对狗骨式钢梁影响的规律。     

圆孔蜂窝钢梁非线性屈曲有限元分析

采用有限元分析软件ANSYS,对圆孔蜂窝钢梁进行非线性屈曲分析,探讨了几何非线性和材料非线性对非线性屈曲抗弯承载力的影响,从而为进一步研究圆形蜂窝梁提供了参考。     

基于ANSYS软件的焊接工字型截面梁残余应力的有限元分析

根据热弹塑性应力理论、有限元理论 ,用大型有限元软件ANSYS对焊接工字型截面梁进行残余应力分析 ,分析结果表明 ,焊接残余压应力的分布与截面几何参数有关 ,为用有限元分析焊接工字型截面梁残余应力提供了一种方法。     

方钢管混凝土柱—钢梁外隔板式节点非线性有限元分析

选择合适的材料本构模型,利用三维实体单元,对方钢管混凝土柱-钢梁外隔板式节点建立了同时考虑几何非线性和材料非线性的有限元分析模型,模拟分析了单调加载下节点的受力性能,较为精确地分析了节点区应力分布.结果表明,由有限元模型所得的位移曲线与试验所得的低周反复荷载作用下的骨架曲线极为相似,由有限元模型所得的应变分布和发展规律与试验结果一致.外隔板式节点的梁端弯矩一部分通过柱腹板两侧隔板传递到柱钢管腹板和核心混凝土,另一部分则主要通过柱角两内侧各0.25倍柱宽范围内的隔板直接传递给柱钢管翼缘和核心混凝土,柱角附近的隔板出现严重的应力集中,节点因受压翼缘屈曲、梁翼缘变截面最窄处形成塑性铰而破坏.节点核心区混凝土符合斜压杆受力机制.     

Elastic shear buckling characteristics of LiteSteel beams

LiteSteel beam (LSB) is a new cold-formed steel hollow flange channel beam. The unique LSB section is produced by a patented manufacturing process involving simultaneous cold-forming and dual electric resistance welding. To date, limited research has been undertaken on the shear buckling behaviour of LSBs with torsionally rigid, rectangular hollow flanges. For the shear design of LSB web panels, their elastic shear buckling strength must be determined accurately including the potential post-buckling strength. Currently the elastic shear buckling coefficients of web panels are determined by assuming conservatively that the web panels are simply supported at the junction between the flange and web elements. Therefore finite element analyses were carried out to investigate the elastic shear buckling behaviour of LSB sections including the effect of true support conditions at the junction between their flange and web elements. An improved equation for the higher elastic shear buckling coefficient of LSBs was developed and included in the shear capacity equations of Australian cold-formed steel codes. Predicted ultimate shear capacity results were compared with available experimental results, both of which showed considerable improvement to the shear capacities of LSBs. A study on the shear flow distribution of LSBs was also undertaken prior to the elastic buckling analysis study. This paper presents the details of this investigation and the results including the shear flow distribution of LSBs.     

方钢管混凝土柱-钢梁外隔板节点拟静力试验研究

通过对2个方钢管混凝土柱-工字钢梁外隔板式节点试件进行的拟静力加载试验,研究节点在反复循环荷载作用下的滞回性能、耗能能力、延性、应力分布和传力机制。试验结果表明,节点具有较高的承载力以及较好的延性和耗能能力,外隔板式节点的梁端弯矩一部分通过柱腹板两侧隔板传递到柱钢管腹板和核心混凝土,另一部分则主要通过柱角两内侧各0.25倍柱宽范围内的隔板直接传递给柱钢管翼缘和核心混凝土。柱角附近的隔板出现严重的应力集中,影响节点的耗能和延性。对节点建立同时考虑几何非线性和材料非线性的有限元分析模型,模拟分析了节点的受力性能。结果表明,由有限元分析所得的位移曲线与试验所得的骨架曲线极为相似,由有限元模型所得的应变分布规律与试验结果一致。     

Load capacity and deflection of fire-resistant steel beams

The methodology of defining safety of constructions in fire has not yet been sufficiently verified and agreed upon. This paper includes calculation results for steel beams, which prove that the ultimate load-bearing capacity predicted by plastic design theory, which is valid in engineering calculations, is not sufficient for determining the critical temperature. The reason is that this temperature tends to be limited in some cases by large deflections of beams in fire.     

钢板深梁填充钢框架静力弹塑性分析

本文对一个六层纯钢框架和钢框架内填钢板深梁结构进行静力弹塑性分析,对比两者在多遇地震与罕遇地震作用下层间位移角与层间位移的大小,找出多遇和罕遇地震下的性能点,对建筑物进行地震评估。     

Experiment on restrained steel beams subjected to heating and cooling

This paper describes the performance of restrained steel beams in fire experiments that were completed recently in the Fire Laboratory of Tongji University. It is shown that restrained steel beams have better fire-resistant capability than isolated steel beams. At the beginning of heating due to fire, an internal axial compression force was produced in the restrained beams by thermal expansion. When the temperature was up to a certain value, the internal axial compression force in the beams began to decrease, and eventually the compression force vanished and the tension force was initiated, due to the increase in the deflection of the beams causing a catenary action. This phenomenon explains why a restrained steel beam has higher fire-resistant capacity than an isolated steel beam. After the fire went out, a larger tension force was produced in the restrained steel beams by contraction as the temperature decreased. In addition, local buckling at the bottom flange of the beams near the ends was observed in the experiments. According to the results from the experiments, the stiffness of the axial restraint plays an important role in the behavior of restrained steel beams subjected to heating and cooling in a fire.     

弯曲型摩擦钢桁架连梁(BFTCB)抗震性能研究

文章提出一种弯曲型摩擦钢桁架连梁(BFTCB),其主要利用位于下弦杆的摩擦装置的滑移代替下弦杆的塑性变形,从而保护钢桁架主体不发生破坏,同时由于摩擦装置具有良好的耗能能力,从而获得稳定的耗能能力。首先通过循环往复加载试验对弯曲型摩擦钢桁架连梁的变形及耗能能力进行研究。试验结果表明:连梁的梁端位移主要集中在摩擦装置的滑移上,弯曲型摩擦钢桁架连梁具有稳定的滞回行为。之后建立准确有效的有限元模型,并利用试验结果进行标定。通过有限元分析对弯曲型摩擦钢桁架连梁的受力机理以及摩擦装置的性能进行详细研究。通过有限元参数分析,研究不同摩擦起滑力、连梁跨高比对其抗震性能的影响,最后给出了弯曲型摩擦钢桁架连梁的承载力计算方法。     

粘钢加固钢筋混凝土梁非线性有限元分析

采用分层有限元法对钢筋混凝土梁进行非线性分析 ,将梁沿轴向分段 ,并将梁横截面分层 ,用c语言编制了计算程序 ,得到其荷载 挠度全过程曲线 ,计算结果与试验结果较一致。