基于钢管混凝土柱的梁柱混合节点研究进展分析

钢管混凝土柱具有强度高、塑性好、抗震性能优越和施工便捷等优势,广泛应用于高层建筑、大跨度空间结构、桥梁结构和工业建筑等领域。型钢混凝土梁、钢筋混凝土梁及其预应力梁因建造成本较低等原因常与钢管混凝土柱连接,形成了新型混合连接节点,然而其节点的设计和施工依然存在挑战。文章综述了此类梁柱混合节点的连接类型、试验研究、数值模拟、理论分析及其工程应用,并依托广汕铁路新塘站项目候车层的钢管混凝土柱-预应力钢筋混凝土梁混合节点,设计加工了缩尺混合节点试件,进一步研究其抗震性能并提出相应设计方法,为此类新型混合节点的工程应用提供技术支撑。     

钢管混凝土柱螺栓连接钢梁节点的抗震性能分析

为了改进施工过程,同时确保房屋的抗震性能,提出了一种新型的连接类型,用于钢管混凝土柱和钢梁的连接处设计。该连接具有外伸端板的特性,出厂前与钢梁焊接在一起,然后在现场用高强钢将其与钢管混凝土柱螺栓连接。对这种螺栓连接端板节点的抗震性能进行试验研究,并通过对3个足尺节点模型进行试验,评估了混凝土楼板和削弱型梁截面对其的影响。试验结果表明:楼板对节点强度的作用显著,削弱型梁截面能有效地将屈曲区域转移到远离焊接点的位置。同时,螺栓连接端板节点的分析模型也采用OPENSEES1.7.3模拟了试验结果。     

新型装配式楼板与钢梁连接节点的承载性能有限元分析

提出一种应用于装配式交错桁架结构的新型空心楼板与钢梁的连接方式,并建立基于ABAQUS的有限元模型对其受力性能进行了研究。通过17个梁板连接节点的有限元模型,研究了T型连接钢板高度、强度以及埋置深度、螺栓强度、锚固钢筋直径、有无锚固钢筋和后浇混凝土强度等参数对梁板节点承载力的影响。研究结果表明:设置T型连接钢板影响后浇混凝土的破坏位置,会造成应力集中现象;随着T型连接钢板高度的增加,梁板节点的刚度也不断增加,但其对极限承载力影响不大;T型连接钢板的埋置深度是影响梁板节点承载力的关键因素,埋置深度越大,承载力越大;T型连接钢板的强度、螺栓强度、锚固钢筋直径对承载力影响较小,后浇混凝土强度对梁板节点承载力有一定影响,强度越大,承载力越大;梁板节点的受剪承载力随着抗剪钢筋直径的增加而逐渐增加,钢筋直径大于20 mm时,承载力增幅有限,其最大剪切应力能满足实际工程的需要。     

预制装配式混合框架屈曲约束狗骨式节点抗震性能试验研究

为充分发挥装配式混凝土结构施工便捷的特性及钢结构中狗骨式钢梁的抗震性能优势,提出了预制装配式混合框架屈曲约束狗骨式节点。该混合框架节点由预制钢筋混凝土柱和预制钢-混凝土混合梁通过高强螺栓连接而成,其中混合梁由屈曲约束狗骨式钢梁段与混凝土梁段采用高强螺栓连接。完成了2个框架中节点及2个框架边节点的低周往复加载试验。通过对节点的破坏形态、滞回曲线、骨架曲线、耗能能力及变形能力、承载力及刚度退化的研究,对节点类型及梁内是否布置预应力筋对该节点抗震性能的影响进行了分析。研究结果表明：该节点的拼装方式采用全螺栓连接,施工便捷;节点的破坏主要集中于钢梁段,达到了塑性铰外移的目的;节点梁内布置预应力筋能明显提高混凝土梁段的抗裂性能及节点整体抗震能力;提出了该节点中梁端受弯承载力计算方法,试验值与计算值吻合较好。     

双边钢次梁插入混凝土框架主梁的节点承载力试验研究

钢次梁插入混凝土框架主梁的节点连接是一种新型的节点连接形式.通过采用节点性能试验的方法,对这种连接节点的受力性能和工程适用性进行了研究.试验结果表明,钢次梁插入主梁的连接节点为半刚性连接节点,抗弯能力有限,且当上翼缘焊接板与翼缘板的横向面积比控制在0.45～0.60时,节点的破坏始于钢次梁上翼缘连接焊板的拉伸屈服,属于次要构件的塑性破坏,满足安全设计和承载力的要求.     

波形或桁架式钢腹板的预应力钢混组合桥主梁的安全性能和使用性能评估

在许多国家,预应力混凝土箱梁被认为是中等跨径(30～50m)混凝土梁最有效的结构形式。但是当混凝土梁的单跨长度超过50m时,相对钢梁,混凝土箱梁自重问题成为其最大约束。因此,在韩国,中等跨径桥梁主要采用钢箱梁。在20世纪,研究者们多次尝试提高预应力混凝土箱梁结构的有效性,最终采用混凝土-钢混合梁以减轻结构自重。但是,混合桥采用不同类型钢腹板及不同连接形式,会引起结构安全性能和使用性能的变化。为了全面了解钢腹板梁及钢腹板连接形式的性能,对5根带腹板的预应力混凝土梁进行静力荷载试验。这5根试件中,有2根混合梁采用波形钢腹板,而另3根采用桁架式钢腹板。结果显示:通过加强钢腹板与预应力筋的连接节点,可以改善使用性能相关问题(开裂荷载和挠度)及安全性能相关问题(刚度和极限承载力)。     

异形空心构件螺栓端板连接节点设计与制作

国外某高铁站屋盖钢结构的主要构件采用十字形、U形等异形截面,主要节点均采用摩擦型高强螺栓端板连接,具有避免现场焊接、安装方便和施工快捷等优点。但由于采用内法兰连接时在端板附近要开手孔,会削弱构件在端板附近的截面尺寸,导致节点受力异常复杂。采用常规计算方法无法准确评估手孔对节点承载能力的影响,故采用考虑接触和螺栓预拉力的非线性有限元方法进行分析。对结构中3种关键螺栓端板连接进行了受力分析,总结出节点的受力性能和破坏形式,供结构设计与施工参考。     

型钢混凝土组合结构钢骨开孔与穿筋深化设计

甘肃省会展中心五星级酒店工程主体结构采用箱形钢管混凝土柱+钢框架梁+H型钢混凝土简体组合结构,地下为劲性钢-混凝土组合结构.本工程钢结构构件截面种类多,连接节点类型多、构造复杂.重点介绍了钢骨柱穿筋孔、钢骨梁穿筋孔以及钢骨其他开孔的形式,以及组合结构节点设计原则.另外指出,钢结构制作加工时,需预留穿筋孔眼,钢骨开孔要本着连接节点构造简单、等强受力、便于施工的原则.     

预应力预制混凝土框架节点形式及设计方法

构建了一种新型的预应力预制混凝土框架节点,该节点的梁、柱构件通过预应力筋、角钢以及高强螺栓连接而成,经试验验证该类节点兼具良好的自复位能力和耗能能力。为了便于推广应用,针对这种基于角钢-高强螺栓连接的预应力预制混凝土框架节点的梁柱连接,提出设计方法,包括使用阶段的承载能力极限状态和正常使用极限状态并考虑施工阶段节点的工作状态,提出确定预应力筋的面积、初始张拉力、角钢尺寸及螺栓连接位置等设计参数的方法。     

梁柱节点处不同强度等级混凝土的施工方法

一、梁柱节点处不同强度等级混凝土采取随梁浇筑方法 在通常情况下，为便于施工，可以与设计人员协商采用梁柱节点处的混凝土随梁一同浇筑的方法。具体措施：（1）若柱混凝土的强度等级比梁板混凝土的强度等级高一级时，梁柱节点处的混凝土可随梁一同浇筑；（2）若柱混凝土的强度等级超过梁板的混凝土强度等级大于二级，而柱四边均有现浇梁时，梁柱节点处的混凝土可随梁一同浇筑。     

Experimental study on joint of spliced steel-PSC hybrid girder, Part I: Proposed parallel-perfobond-rib-type joint

The object of this study is to determine and propose a suitable joint type for spliced hybrid I-girder bridges consisting of steel girders at the mid-span and PSC (prestressed concrete) girders at the supports. Three joint types are experimentally tested on small-scale steel-PSC hybrid beams to determine the type offering the best combination of structural capacity and constructional convenience. One joint type, first suggested and trialed in the present study, is composed of multiple perfobond rib connectors attached in parallel to upper and lower plates located between the steel girder and the PSC girder. The two other types incorporate the stud connectors, which are widely used in connecting steel and concrete, but differ in the amount of reinforcement. The test results reveal that a joint consisting of parallel perfobond ribs and a joint consisting of studs with sufficient reinforcement show the similar beam strength and failure modes resulting from the failure of the PSC components. Notably, beams of the proposed joint type consisting of perfobond ribs, compared to those with studs, show higher stiffness and strength prior to reaching their ultimate strength, as well as lower strains in the joint. Indeed, with the parallel-perfobond-rib-type joint, advances in constructional convenience as well as structural capacity can be anticipated. Thus, it is concluded that the proposed joint type is a more suitable system for spliced steel-PSC hybrid girder bridges.     

Experimental study on joint of spliced steel-PSC hybrid girder, part II: Full-scale test of spliced hybrid I-girder

A full-scale test is conducted on a spliced steel-PSC (prestressed concrete) hybrid I-girder of 40 m length, in order to verify a new type of joint splicing steel and PSC segments. The spliced hybrid girder offers a competitive solution to medium-span bridges, with its various benefits such as a transportation constraint solution, high quality girders, span-length flexibility, the advantage of a hybrid system, and others. At the same time, it requires a proper joint connecting its PSC and steel segments at a site. A new type of joint consisting of parallel perfobond ribs, encased prestressed concrete, and steel plates, is adopted and tested to remove the vulnerabilities from joint areas where PSC I-section and steel I-section are connected. After the PSC segments with the joint and the steel segment are fabricated in a factory, they are transported to a test site and spliced into one girder. The experimental results show that the spliced steel-PSC hybrid I-girder is of sufficient strength, ductility, and stiffness without giving failure of joint. Indeed, the joint clearly transfers the load between the steel and PSC segments without incurring damage. It is concluded that the applied joint can be an effective system guaranteeing sound performance up to the ultimate capacities of the spliced steel-PSC hybrid I-girder.     

高性能钢梁混杂设计方法及整体稳定性分析

阐述高性能钢梁的混杂设计概念,通过必要实例说明高性能混杂钢梁的优点,并运用ANSYS有限元程序,分析焊接H型混杂简支梁在跨中集中荷载作用下的整体稳定性。     

轻型格栅支护与围岩共同作用的力学性能试验研究

本文采用在实验室条件下、小比例格栅支护模型，对轻型格栅支护作为一种施作及时，与围岩紧密相贴的柔性支护的作用机理进行了截面为三弦杆、四弦杆单独作用、与喷砼共同作用、有无仰拱，毛洞、素喷砼等不同试验组合的对比研究。从围岩与支护共同作用出发，在多榀格栅联合支护下，通过量测格栅弦杆上的应变、洞室的位移、支护结构与围岩间的接触应力，探索格栅支护的力学性能及破坏机理，对格栅支护的作用效果及力学性能做出客观的综合评价。     

多钢种混用工字钢梁抗弯极限承载力研究

以受弯构件弯扭屈曲理论作为理论基础,对25根上翼缘加强型单轴对称混用工字钢梁及相同跨径与截面尺寸的匀质钢梁进行极限承载力有限元计算,研究多钢种混用钢梁同匀质钢梁在破坏模式、极限承载力等方面的差异性.对有限元计算结果进行回归分析,得出了可用于设计的临界弯矩计算公式.研究结果表明,合理采用混用钢梁的构造理念,可以在满足承载力要求的同时优化钢材搭配,降低工程造价,做到物尽其用.     

三塔结合梁斜拉桥结合段刚度匹配研究

结合梁斜拉桥主跨结合梁和边跨混凝土梁因为材料以及截面形式不同,所以二者在刚度上存在较大的差异,为保证应力和变形沿桥纵向顺畅协调地传递,需使主梁刚度在结合段处平稳过渡。该文结合武汉二七路长江大桥,首先建立其结合段空间有限元模型,然后在此基础上增大、减小结合段钢梁板材厚度以及加劲肋密度建立结合段刚度匹配优化模型,通过对此5个模型在其最不利工况下的计算结果进行对比分析,得出结合段最佳的刚度匹配形式。结果表明,增大钢梁板材厚度以及加劲肋密度为结合段最佳的刚度匹配形式,可以改善结合段纵向正应力传递。     

Hybrid steel plate girders subjected to patch loading, Part 2: Design proposal

The resistance of plate girders subjected to patch loading has been studied thoroughly for the case of homogenous girders. The particular case of hybrid girders has been generally treated identically than for homogenous specimens. In this paper, the current EN1993-1-5 formulation is evaluated and some peculiarities concerning the treatment of hybrid girders subjected to patch loading are pinpointed. It is numerically demonstrated that the moment capacity of the flanges does not play any role in the resistance of plate girders to patch loading as predicted in EN1993-1-5. Accordingly, a design proposal which corrects the current EN1993-1-5 formulation is presented at the end of the paper.     

斜拉-悬吊协作体系桥的颤振稳定性研究

运用多模态颤振有限元分析方法 ,分别从悬索的矢跨比、吊跨比、斜拉索索面布置形式、边跨辅助墩的设置以及桥面主梁构成等设计参数着手 ,对主跨 14 0 0m的斜拉 -悬吊协作体系桥进行了颤振稳定性分析 ,指出了影响斜拉 -悬吊协作体系桥颤振稳定性的关键设计参数 ,并从抗风性能角度探讨了斜拉 -悬吊协作体系桥的合理结构型式。     

Longitudinally stiffened hybrid steel plate girders subjected to patch loading

Hybrid girders subjected to patch loading have been analyzed in a detailed fashion for the case in which the plates that assemble the girders are transversally stiffened. Scant work, however, is available for the case in which the girders are hybrid and, simultaneously, longitudinally stiffened. The driving force for developing the present research work is to complete the knowledge of the patch loading field for the particular structural alternative of a hybrid steel plate girder assembled with a longitudinal stiffener. In the current paper, a numerical database of 255 simulations on longitudinally stiffened steel girders subjected to patch loading developed by the authors is presented. The results obtained are used for assessing the resistance of longitudinally stiffened hybrid steel plate girders subjected to patch loading. Some discrepancies between the numerical and EN1993-1-5 results are pinpointed. A design proposal which enhances the current EN1993-1-5 formulation is given at the end of the paper.