Nonlinear analysis for PC box-girder with corrugated steel webs under pure torsion

A three dimensional finite element model of PC box-girder with corrugated steel webs taking material nonlinearity into consideration is established to investigate the behavior under pure torsion. The torque–twist curves and ultimate torsional strength predicted by FEM show good agreement with test data. Results obtained from finite element model indicate that specimens go through three stages subjected to pure torsion and the shear flow in concrete top or bottom flange is not equal to that in corrugated steel webs. Parametric study is carried out including effect of corrugation, effect of thickness of web, effect of strength of concrete, and effect of prestressed tendons. It is shown that the ultimate torsional strength of specimens is in linear proportion to shear modulus and thickness of corrugated steel webs and to compressive strength of concrete.     

Shear behavior of partially encased composite I-girder with corrugated steel web: Numerical study

Shear behavior of partially encased composite I-girders with corrugated web has been investigated analytically and numerically in this paper. A 3-D finite element model with geometric and material nonlinearity is established and verified by the experiments. Subsequently, a parametric study is carried out to examine the effects of geometric and material properties on the shear behavior which includes corrugation, height, thickness, connection degree between steel web and concrete encasement. It is found that the ultimate shear strength of steel I-girders is improved with increases in the thickness, height and yield strength of corrugated web, while the ultimate shear strength of partially encased composite I-girders increases with the thickness, yield strength of corrugated web and the thickness, compressive strength of concrete encasement. However, the stud stiffness has little influence on the ultimate shear strength. Moreover, the concrete encasement improves the shear strength of steel I-girders, the degree of improvement increases with the thickness and compressive strength of the concrete, but decreases drastically with the thickness of corrugated web. Therefore, it is suggested that concrete should be poured on the corrugated web with thin thickness or low yield strength to prevent buckling occurrence before yielding of steel web. Finally, shear strength prediction equations are proposed and verified by numerical results. The calculated shear strength agree well with the numerical results for steel I-girders before and after composite with concrete, which indicates that the proposed analytical equations can be applied to predict the shear strength of such partially encased composite girders with corrugated web.     

具有钢翼缘的波形钢腹板的面内刚度计算

针对波形钢腹板与混凝土板的连接形式,通过有限元模拟分析,提出对于具有钢翼缘的波形钢箱梁应考虑其腹板面内刚度的必要性。通过对国外已建34座波形钢腹板箱梁桥的腹板进行统计分析,得出波形钢腹板面内刚度受波形腹板的腹板高度与腹板厚度比值的影响较大的结论,并引入“有效宽度”的概念,提出了能包罗常用波形腹板有效宽度的简单有效的面内刚度计算公式。     

竖波钢板组合剪力墙等效塑性铰长度研究

竖波钢板组合剪力墙因内嵌波形钢板的几何形状优势，表现出良好的抗震性能。在基于性能的抗震设计要求下，竖波钢板组合剪力墙等效塑性铰长度的确定对合理评估其塑性变形能力至关重要，但国内外已有公式均难以体现其复杂的组合作用，有待提出针对性的简化计算式。基于课题组前期试验成果，通过对竖波钢板组合剪力墙试验破坏现象和受力机理的分析，采用OpenSEES软件，建立有限元模型。扩展研究波形钢板几何参数、约束边缘H型钢柱、分布钢筋配置、混凝土强度、设计轴压比以及剪力墙高宽比等参数对等效塑性铰长度的影响规律，发现使用波形钢板含钢率可以更有效地反映波形钢板几何参数对等效塑性铰长度的影响，而混凝土强度和分布钢筋配箍率与等效塑性铰长度呈负相关。通过理论分析和推导提出多参数控制的竖波钢板组合剪力墙等效塑性铰长度简化计算式，该式适合于估算竖波钢板组合剪力墙的塑性变形能力，可以用于该类剪力墙的弹塑性分析。     

Shear buckling strength and design of curved corrugated steel webs for bridges

This paper presents the shear buckling strength and design of curved corrugated steel webs for bridges considering material inelasticity. The inelastic buckling strength is determined from buckling curves based on the proposed shear buckling parameter, which is a function of the elastic shear buckling strength of steel web and the material shear yielding strength. A finite element analysis is carried out to study the geometric parameters affecting the shear buckling strength of curved corrugated steel webs for bridges. Based on the numerical results, a shear buckling parameter formula is proposed with no need to calculate either local, global, or interactive buckling parameters. But it depends on the geometric properties of the curved corrugated web profile. Another formula is presented to maximize the shear buckling capacity of curved corrugated web. The proposed formulae agreed well with the published experimental data. The curved corrugated webs produce a tremendous increase in the shear buckling strength and considerable weight saving in regard to the corresponding trapezoidal corrugated webs. The corrugation angle has a considerable effect on the behavior of curved corrugated webs, where higher corrugation angles produce a tremendous increase in the shear buckling strength of curved corrugated webs. It was found that the proposed approach provides a good prediction for the shear buckling strength of curved corrugated steel webs of bridges.     

波纹侧板-方钢管混凝土柱轴压性能研究

为研究波纹侧板-方钢管混凝土柱轴压性能,进行了1个1/2缩尺试件轴压试验,对其受力机理、破坏模式进行分析,发现该类柱具有较好的延性及较高的承载能力。同时对波纹侧板-方钢管混凝土柱进行了有限元分析,分析结果表明：由于波纹板具有较高的侧向刚度,使核心混凝土能够得到较好的约束,但是波纹板基本不承担轴向荷载;破坏形式为钢管局部屈曲、波纹板向外鼓曲、钢管内混凝土及核心混凝土被压碎;随着波纹板厚度增加,承载力、延性提高;随着波纹板强度提高,延性略有提高,对承载力影响不大;承载力随混凝土强度提高而提高,但是延性变差。提出了波纹侧板-方钢管混凝土柱轴压承载力实用计算式,计算值与有限元分析值、试验值吻合较好。     

波形钢腹板组合箱梁桥剪力滞效应研究

波形钢腹板组合箱梁由于其力学性能和经济性能比普通箱梁优越而正被广泛地使用,本文介绍了计算波形钢腹板组合箱梁桥剪力滞系数的能量变分法,用有限元分析软件ANSYS进行了波形钢腹板组合箱梁桥的建模,并采用能量变分法的结果加以验证。结果表明采用有限元法模拟波形钢腹板组合箱梁桥的剪力滞效应效果较好,分析了波形钢腹板组合箱梁桥横桥向和纵桥向剪力滞系数的变化规律。     

高轴压比SRC剪力墙抗震性能分析

采用MSC.Marc建立SRC剪力墙有限元分析模型,通过对5片SRC剪力墙试件的非线性有限元分析,验证了有限元模型的合理性和可靠性。对轴压比和钢骨配钢率对SRC剪力墙抗震性能的影响进行了参数分析。SRC剪力墙的承载能力随轴压比的增加而提高,变形能力随轴压比的增大而降低;承载能力随配钢率的增加而提高,变形能力也有所提高,但轴压比较高时不明显。     

Ultimate load behaviour of webs in steel–concrete composite plate girders

The paper is concerned with the tension field action in webs of steel–concrete composite plate girders. A three-dimensional finite element model has been used to carry out nonlinear analyses on composite plate girders. The results obtained from the finite element analyses are compared with those from experiments. It is observed from the comparative study that the proposed nonlinear finite element model is capable of predicting the ultimate load behaviour of steel–concrete composite plate girders to an acceptable accuracy. Results are presented to explain the development of the tension field action in the webs and to illustrate a measure of the contribution by the concrete slab acting compositely with the girder to the changes in tension field compared to a plain steel girder.     

A parametric study on ultimate strength of single shear bolted connections with curling

Recommended procedures of finite element modeling for predicting the structural behaviors of single shear bolted connections in cold-formed austenitic stainless steel are presented in this paper. It was shown that predictions by FE analysis method were in a good correspondence with test results for ultimate behaviors such as failure mode, ultimate strength and out-of-plane curling. A parametric study on four-bolted connections with extended variables; plate thickness, end distance and edge distance is performed in order to consider the influence of curling on ultimate strength for practical design and ultimate strengths obtained from FE analysis results are also compared with those calculated by current design standards and recently modified equations by Kuwamura. It is found that Kuwamura's equations, which are specified by SSBA design manual are more valid for predicting ultimate strength of bolted connection without curling compared to other design specifications, while for specimens curled in FE analysis, Kuwamura's equations overestimated the ultimate strength due to strength reduction caused by curling and current other design standards showed a tendency to underestimate the ultimate strength of block shear fracture regardless of curling occurrence. Consequently, revised design formula for considering the effect of curling on bolted connection is proposed in this paper using correlations between strength reduction ratio and plate thickness. Furthermore, the validation of proposed design equations in predicting the ultimate strength is verified through comparisons with existing test results and additional FE analysis results.     

Application of corrugated plates as the web of steel coupling beams

Nowadays, steel coupling beams are used as an efficient alternative to reinforced concrete (RC) coupling beams. Particularly in the coupled shear walls system, coupling beams are the main members for dissipating seismic energy. In this paper, for the first time the application of corrugated plates as the web of steel coupling beams (rather than flat web and its stiffeners) is studied as a proposition for improving seismic behavior of such beams. The study addresses the linear elastic buckling analysis and non-linear analysis of steel coupling beams with flat and corrugated webs using finite element technique for which ANSYS software is employed. 160 models have been studied, considering parameters such as shape of web plate (flat and three corrugated types, including trapezoidal, curved, and zigzag), web thickness, number of corrugations, and corrugation angle. The finite element results are validated through comparison with the experimental results of a common steel coupling beam, tested by other researchers. In addition to the advantages of eliminating web stiffeners, results of this study show that the application of corrugated web with the proposed geometric criteria makes it possible to achieve further rotation capacity in comparison with common steel coupling beams. Finally, a design approach for corrugated web of steel coupling beams, accompanied by a practical example, is presented.     

大跨径波形钢腹板组合箱梁桥剪力滞效应

为了研究大跨径波形钢腹板组合箱梁桥的剪力滞效应,结合1座采用悬臂施工的大跨径波形钢腹板箱梁桥,分别建立平面杆系有限元模型和空间实体有限元模型,模拟施工过程,选取3个关键截面,研究了波形钢腹板组合箱梁桥在不同施工阶段的剪力滞效应分布规律。结果表明:大跨径波形钢腹板组合箱梁桥的剪力滞效应随着施工阶段的推移是一个动态变化过程,在悬臂施工阶段,剪力滞效应变化较快,在施工阶段后期,剪力滞效应变化缓慢;最大剪力滞效应发生在最大悬臂状态时的端部截面。     

改进型组合钢板剪力墙有限元分析与研究

为改进型组合钢板剪力墙设计了合理的有限元模型,对纯钢板和3种不同混凝土板厚度以及3种跨高比的组合墙进行了有限元对比模拟分析.结果表明：两侧混凝土板对组合墙的承载力影响不大但可提高其后期刚度,并可有效限制钢板的出平面屈曲;同时,随着跨高比的增大,结构整体承载力有所提高.在此基础上,比较了几组模型的抗剪承载力性能,以及预制墙板对其屈曲荷载的影响,并给予建议的简化模型.可以看出,改进型组合钢板剪力墙有较好的延性以及耗能性能,能充分利用材料的性能.     

波形钢板剪力墙抗震性能试验研究

为研究波形钢板剪力墙在水平荷载作用下的抗侧力性能,完成了水平波形和竖向波形的钢板剪力墙模型的低周往复加载试验,并采用ABAQUS有限元软件对波形钢板剪力墙模型进行了模拟分析。试验结果表明：波形钢板剪力墙结构具有较高的侧向承载力、较强的抗剪屈曲能力和稳定的滞回性能;竖向波形钢板剪力墙在加载过程中发生了沿墙体对角线的X形剪切破坏;水平波形钢板剪力墙在加载过程中未出现波形钢板的屈曲破坏。因此,水平波形钢板剪力墙的极限荷载比竖向波形钢板剪力墙的更高、延性更好、滞回曲线更加饱满。在水平受剪时,竖向波形钢板剪力墙易产生拉压效应,水平波形钢板剪力墙易发生H型钢柱屈曲。波形钢板与边缘约束H型钢柱之间的焊缝未出现开裂,焊缝连接保证结构的整体性能。对比有限元分析结果与试验得到的数据,水平波形钢板剪力墙的荷载、位移比竖向波形钢板剪力墙的更接近试验值。采用有限元法对不同波角和钢板厚度的水平波形钢板剪力墙的抗侧性能进行了分析,结果表明：当钢板比较薄的时候,容易发生波形钢板的剪切破坏;当钢板较厚的时候,容易发生边缘约束H型钢柱的过早屈曲,对结构的承载力和延性不利;当波形钢板的波角为45°时,波形钢板剪力墙的承载力以及延性性能最佳。波角过大或过小时,剪力墙承载力均有所降低。因此,水平波形钢板剪力墙宜采用45°波角与厚度适中的钢板。     

波形钢腹板-钢管混凝土翼缘组合梁桥疲劳性能的多尺度有限元分析

对波形钢腹板-钢管混凝土翼缘组合梁进行了多点约束界面连接及多尺度有限元建模,通过计算分析和理论公式对比,验证了疲劳寿命预测精度和计算分析效率。采用多尺度模型对波形钢腹板钢管翼缘连接部位应力特性进行了分析,比较了波形角以及波形转角曲率半径与波形高度比值对连接部位应力特性的影响。结果表明:采用多尺度模型可在不影响疲劳寿命预测精度的前提下,较为有效地提高波形钢腹板 钢管组合梁疲劳分析的计算效率,其计算分析时间比精细化模型可节约28.9%,而寿命预测相对误差可控制在2%以内;对于梁结构建模,采用多尺度模型计算分析时间比精细化模型可节约40.7%,而寿命预测相对误差可控制在5%以内;多尺度模型模拟连接部位主应力分布规律与精细化模型一致,最大主应力值相对误差在5%以内;该方法可较好地实现对波形钢腹板与钢管混凝土翼缘连接部位不利应力状态的模拟,可为波形钢腹板 钢管混凝土翼缘组合梁的相关疲劳损伤分析提供参考。     

On the hysteretic behavior of trapezoidally corrugated steel shear walls

At present, corrugated plates have numerous applications such as web of plate girders and aerospace applications. Higher out‐of‐plane stiffness and initial elastic strength of the corrugated plates compared with flat plates are reasons for consideration. This study investigates the behavior of trapezoidally corrugated steel plate shear walls (TCSPSWs) under monotonic and cyclic loadings. Finite element analyses that include both material and geometric nonlinearities are employed for the examination. The results from finite element analysis are verified through tested specimen findings. Moreover, the behavior of the steel shear walls with the flat infill panels and the corrugated plate infill panels is compared. The results show that explicit dynamic analysis is the most suitable analysis for the TCSPSWs under quasi‐static loading. Furthermore, although strength of the TCSPSWs obtained from the finite element analysis and the test are fully coincident in elastic region, nonetheless, they are fairly coincident in elastic–plastic and plastic region. Copyright © 2012 John Wiley & Sons, Ltd.     

波形钢腹板组合槽型梁静载试验与有效预应力分析

波形钢腹板组合槽型梁是一种新型下承式开口薄壁桥梁结构,对4片按照1/4相似比进行设计的试验梁进行两点对称加载和有限元分析,研究两组试验梁在对称荷载作用下的荷载位移关系、截面应变分布、裂缝发展规律和破坏形态等,分析张拉预应力和释放预弯力后试验梁底板混凝土的有效预压应力。研究表明：竖向荷载作用下试验梁符合平截面变形规律,应忽略波形钢腹板对抗弯刚度的贡献和底板混凝土对抗弯承载力的抵抗作用;试验梁混凝土受压区受限于上翼缘板,其应变分布为梯形而非常规的三角形分布;下承式槽型截面的中性轴偏低,波形钢腹板预弯钢梁反弹能够有效地对混凝土施加预压应力;采用波形钢腹板能有效提高槽型梁的预应力施加效率,文中建议的波形钢腹板组合梁预应力等效荷载法,能准确计算此类结构的混凝土有效预压应力;两组试验梁由于配筋量的不同分别发生塑性和脆性弯曲破坏;波形钢腹板组合槽型梁的自重轻、抗弯刚度较大、具有较好的延性和抗裂性能。     

波纹腹板H型钢梁柱刚接节点静力性能

波纹腹板H型钢能以较薄的钢板获得较高的抗剪屈曲能力,从而可以大量节约钢材。但传统的H型钢梁柱刚接节点的构造形式不适用于波纹腹板H型钢梁,为此提出了2种构造形式的波纹腹板H型钢梁柱刚接节点的构造形式。通过静力试验考察这2种节点的承载力以及各截面的内力分布,并对比了试验结果与有限元分析结果及实用设计公式的计算结果,验证了有限元分析的合理性以及实用设计公式的可靠性。使用有限元分析软件ABAQUS对节点进行了参数分析,研究了端板厚度、连接板厚度与波纹断点对节点承载力的影响。     

波形钢板组合结构稳定性及抗剪能力数值分析

为了研究波形钢板混凝土组合墙的稳定性及对拉螺栓的抗剪能力,以三层波形钢板混凝土组合墙为基础,采用有限元软件建立了波形钢板组合墙的有限元模型,模型中混凝土、波形钢板及对拉螺栓均建立实体模型模拟,考虑了材料非线性。研究了螺栓的抗剪能力,分析了钢板与混凝土间协调工作对承载能力及抗剪能力的影响,并与规程计算公式的结果进行了对比。研究结果表明,螺栓的抗剪能力能够满足规程要求,波形钢板与混凝土间的共同工作对承载能力的影响较为明显。     

U形钢板-混凝土高强螺栓连接组合空腹夹层板楼盖结构研究与应用

提出一种多层大跨度结构体系--U形钢板 混凝土高强螺栓连接组合空腹夹层板楼盖,该结构体系由U形钢板-混凝土组合下肋、钢筋混凝土上肋和上下肋间设置的钢筋混凝土剪力键形成的需考虑夹芯层剪切变形的空间楼盖。介绍了该楼盖结构体系的简化计算模型、弹性连续化理论分析方法和实用分析方法,通过仿真模型试验及实际工程应用,验证了弹性连续化理论分析方法与实用分析方法的正确性。研究结果表明：采用由上、下表层薄膜刚度和具有一定抗剪刚度的剪力键夹芯层组成的U形钢板-混凝土高强螺栓连接组合空腹夹层板楼盖简化计算模型进行弹性连续化理论分析,其分析结果与仿真模型试验结果基本相符,相对误差最大不超过5%;按等强和等刚度原则将U形钢板-混凝土组合空腹夹层板折算成钢筋混凝土实腹梁的实用分析方法,其计算结果与仿真模型试验结果基本相符,相对误差最大不超过4%。以黑龙江中医药大学文体中心B区57 m×39 m+57 m×36 m双跨多层（地下1层、地上3层）工程为算例,并与原位测试结果进行比较,说明U形钢板-混凝土高强螺栓连接组合空腹夹层板楼盖安全可靠,且具有较好的经济性。