冷成型钢龙骨-玻特板自攻螺钉连接件力学性能数值模拟研究

冷成型钢龙骨-覆面板材自攻螺钉连接件的力学性能是冷成型钢剪力墙研究的重要组成,其目前研究主要通过试验手段,数值模拟工作相对较少。文章运用ABAQUS有限元软件,考虑螺钉两种剪力方向,对常温下冷成型钢龙骨-玻特板自攻螺钉连接件的力学性能进行数值模拟。有限元模型对实际试件进行简化,采用C3D8R实体单元,同时考虑材料非线性和接触非线性。最后将模拟得到的破坏模式、荷载-位移曲线等与试验结果进行对比,表明提出的有限元模拟方法是有效可靠的。     

ECC混凝土应用于开孔钢板连接件试验研究

基于6个孔内不设贯通钢筋的普通混凝土和ECC混凝土开孔钢板连接件试件的极限承载力试验,研究分析了ECC混凝土对连接件极限承载力和滑移的影响,提出了连接件极限承载力和滑移的计算公式。结果表明,采用ECC混凝土可明显提高混凝土的开裂荷载以及增大钢与混凝土间的相对滑移。通过与非线性有限元以及现有公式的计算结果比较,研究的公式、非线性有限元、Hosain及胡建华公式与试验结果吻合较好。     

集中荷载作用下拱形双钢板混凝土组合墙板的有限元分析

通过ANSYS/LS-DYNA平台对9个拱形双钢板混凝土组合墙板在集中荷载下的试验进行了有限元分析,对试件进行了精细化建模,有限元模型由锤头、上下钢板、混凝土、连接件和底板等部分组成。通过对比试验和有限元分析的力-位移曲线以及破坏特征,验证了有限元模型的准确性。通过该有限元模型分析了影响试件承载力的参数,主要包括混凝土厚度、钢板厚度、连接件间距、连接件直径和矢跨比,结果表明,钢板厚度为影响承载力的主要因素,连接件间距的减小和直径的增加可以提升试件的组合性能,合理的矢跨比应在1/4～1/3之间。     

钢结构集成房屋模块间十字形板-端板连接节点轴压性能研究

现有钢结构模块化建筑的连接节点大多难以用于集成房屋模块间的连接,为此,提出一种十字形板.端板连接件.通过对两个节点试件进行轴压试验,研究节点在轴压荷载作用下的破坏模式和承载力.采用ABAQUS建立试件的有限元模型,有限元分析结果与试验结果吻合较好,验证了有限元模型的正确性.采用该有限元模型分析了十字形板厚、端板厚和柱壁...     

Shear capacity of connect construction between corrugated steel web and concrete lower slab

为改善波形腹板与底板连接构造混凝土浇筑质量与耐久性能,提出翼缘钢板下移至混凝土板底面,开孔板连接件垂直焊接于波形钢板并贯穿钢筋的下包型连接构造。通过设计具有不同开孔板厚度、形状及焊接宽度等参数的连接构造试件,开展标准推出试验,研究其受剪承载力、抗剪刚度、剪切破坏模式以及相对滑移特征。在试验研究的基础上,考虑钢材理想弹塑性、混凝土塑性模型以及钢-混凝土界面非线性接触,建立适用连接构造受剪分析的精细有限元模型,分析结果与试验结果吻合较好。通过验证的有限元模型进行参数分析,结果表明,增加开孔钢板的厚度和混凝土的抗压强度可有效提高受剪承载力。最后,基于模型试验与有限元参数分析结果,提出布置开孔板连接的下包型构造受剪承载力的计算式,可对开孔钢板连接面外受剪承载力进行较为准确地预测。     

钢—压型钢板混凝土组合梁非线性分析

用ANSYS程序对4个简支钢-压型钢板混凝土组合梁试件的受力性能进行非线性分析,在组合梁的有限元模型中,采用弹簧单元考虑了混凝土翼缘板同钢梁间的滑移;梁单元来模拟混凝土所受到的栓钉对其的局部压力;非线性材料本构模型考虑了钢材和混凝土的材料非线性特性。通过与试验结果的对比分析发现该模型可以准确地模拟出钢-压型钢板混凝土组合梁的荷载-挠度曲线、交接面荷载-滑移曲线以及压型钢板组合板的开裂过程,因此,可以利用有限元方法研究组合梁的工作性能。     

波形钢腹板与混凝土底板连接构造受剪承载力研究

为改善波形腹板与底板连接构造混凝土浇筑质量与耐久性能,提出翼缘钢板下移至混凝土板底面,开孔板连接件垂直焊接于波形钢板并贯穿钢筋的下包型连接构造。通过设计具有不同开孔板厚度、形状及焊接宽度等参数的连接构造试件,开展标准推出试验,研究其受剪承载力、抗剪刚度、剪切破坏模式以及相对滑移特征。在试验研究的基础上,考虑钢材理想弹塑性、混凝土塑性模型以及钢-混凝土界面非线性接触,建立适用连接构造受剪分析的精细有限元模型,分析结果与试验结果吻合较好。通过验证的有限元模型进行参数分析,结果表明,增加开孔钢板的厚度和混凝土的抗压强度可有效提高受剪承载力。最后,基于模型试验与有限元参数分析结果,提出布置开孔板连接的下包型构造受剪承载力的计算式,可对开孔钢板连接面外受剪承载力进行较为准确地预测。     

开孔钢板剪力连接件的钢-混凝土组合板有限元分析及参数研究

采用有限元软件ABAQUS对带PBL剪力连接件的钢-混凝土组合板进行了三分点加载模拟,有限元中考虑了混凝土的非线性本构关系、钢板与混凝土之间的非线性接触关系。将模拟结果与试验数据进行对比,结果表明:有限元分析能较好地模拟钢-混凝土组合板的受力全过程。在探讨误差产生的原因的同时,对影响组合板受力性能的因素进行分析。结果表明:孔距和贯穿钢筋对组合板的抗弯极限承载力影响较小,对组合板的刚度影响较大。最后提出了带PBL剪力连接件的钢-混凝土组合板的抗弯承载能力理论计算公式,对参数进行重要性分析后得到满足实际工程应用的简化计算方法。     

侧扭屈曲的波形钢腹板钢筋混凝土连续组合梁的转动刚度

在负弯矩区,连续组合梁将达到由腹板刚度以及混凝土板和剪力连接刚度所产生的侧扭屈曲的极限状态。这3种刚度构成了组合梁的转动刚度。EC4在平面钢腹板组合梁中定义了这种刚度,但对于波形钢腹板组合梁结构中的刚度尚未有结论性研究。文中提出了一个公式,并基于以下几点来对波形腹板型材组合梁的转动刚度进行评估:1)倒U框架模型的4种代表性的试验结果;2)使用ANSYS有限元软件对数值模型进行构建和标定;3)68个数值模型的计算过程。在这些模型中,研究人员试图改变影响转动刚度的所有参数,例如腹板高度和厚度、平板的大小与类型(混凝土板或组合板)、横截面的剪力连接件的数量以及连接件的纵向间距。     

组合结构螺栓连接件初始弹性行为研究

采用通用有限元分析软件ABAQUS对钢和混凝土组合结构摩擦型高强螺栓连接件初始弹性行为进行分析,有限元模型不考虑钢梁、混凝土板、螺栓连接件等材料非线性,并通过已有的试验结果进行验证.通过已验证的有限元模型,分析比较螺栓、钢梁和混凝土等参数变化对初始弹性刚度的影响,并对抗剪模型和剪拉模型两种工况下的不同向初始弹性行为进行...     

Finite‐Elemente‐Berechnungen zum Trag‐ und Verformungsverhalten von Kopfbolzendübeln

Finite Element Calculation of load bearing and deformation behavior of headed studs. In the scope of numerical simulations the composite joint between concrete slab and steel girder is represented by springs or interface elements considering bi‐linear as well as tri‐linear shear‐slip behavior. This method is established to determine the global load bearing behavior for any degree of shear connection. In order to illustrate the concentrated load introduction a three‐dimensional modeling of the shear connector is required. This paper describes a three‐dimensional nonlinear finite element model, which offers the possibility to investigate the local load bearing and deformation behavior of headed studs under shear load. It has been calibrated on shear tests performed by the Institute for Structural Concrete, of University of Technology, Aachen. On the basis of parametrical studies the influence of the concrete strength, the length of the stud as well as the formation of the welded collar have been determined. Furthermore, the limits of the simulation of shear tests are detected.     

九堡大桥引桥组合梁焊钉受力性能研究

九堡大桥引桥为多跨连续组合箱梁桥,截面为开口梯形钢梁与混凝土桥面板组合形式,钢梁与混凝土板间设置了大量的圆柱体焊钉连接件,连接件受力形式与传统钢板梁组合桥不同。文中结合该工程,采用ANSYS有限元程序建立其空间实体模型,采用弹簧单元详细模拟了焊钉,计算了焊钉连接件的受力,分析了焊钉连接件的受力特点。结果表明:焊钉连接件不仅承受沿纵桥向的剪力,还承受沿横桥向的剪力及沿竖向的拉拔力,连接件所受的剪力和拉拔力在全桥范围分布规律复杂。     

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.     

Performance of cellular composite floor beams at elevated temperatures

This paper describes an experimental and numerical study at both ambient and elevated temperatures on the behaviour of full-scale composite floor cellular steel beams. A total of four specimens, comprising two different steel geometries and loading conditions were tested under monotonic loading and at elevated temperatures. All beams were designed for a full shear connection between the steel beam and the concrete flange using headed shear studs. The beams were designed to fail by web-post buckling, which was observed in all the tests. Failure temperature observed in the fire tests indicated that failure by web-post buckling of cellular beams in fire cannot simply be estimated by applying temperature dependent reduction factors on stiffness, as given in codes. A finite element model is then established with both material and geometrical non-linearity using shell elements to compare against the experimental results. The comparison between the finite element prediction and actual test results are quite good in terms of failure modes, load deflection behaviour and ultimate loads.     

Analysis of composite beams in the hogging moment regions using a mixed finite element formulation

Cracking of the concrete slab in the hogging moment region decreases the global stiffness of composite steel-concrete structures and also reduces the effect of continuity, thus making the structural behaviour highly nonlinear even for low stress levels. In this paper, the behaviour of continuous composite beams with discrete shear connection is investigated using a nonlinear mixed finite element model. The model includes appropriate nonlinear constitutive relationships for the concrete, the steel and tension stiffening effect. Furthermore, the discrete nature of the shear connection is embedded in the model and the tension stiffening effects are introduced in the analysis by using a concrete constitutive model proposed in the CEB-FIB Model Code 1990 which incorporates embedded steel. Special attention is paid to the hogging moment regions, where cracking occurs. Comparisons between the numerical analyses and experimental results in the current literature are undertaken to validate the accuracy of the model. Furthermore, a parametric study is carried out to study the influence of span length and degree of shear connection on the strength and ductility of continuous composite beams.     

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 beam finite element including shear lag effect for the time-dependent analysis of steel–concrete composite decks

The paper presents a beam finite element for the long-term analysis of steel–concrete composite decks taking into account the shear lag in the slab and the partial shear interaction at the slab–girder interface. Using the displacement approach, beam kinematics is developed from the Newmark model for composite beams with partial shear connection; warping of the slab cross section is caught with the product of an established function which describes the warping shape, and an intensity function that measures the warping magnitude along the beam axis. Time-dependent behaviour is considered through an integral-type viscoelastic creep law for the concrete. The numerical solution is obtained by means of the finite element method and a step-by-step procedure for evolution in time. A refined, locking free, 13-dof beam finite element is derived considering second and third order hermitian polynomials in order to ensure consistent interpolation of the displacements. The convergence test results and comparisons with the experimental results of composite beams subjected to sustained loads demonstrate the precision of the proposed method. Further applications to realistic cases show the accuracy of the proposed element and its ability to describe the elastic and the time-dependent behaviour of bridge composite decks.     

Effect of shear connector spacing and layout on the shear connector capacity in composite beams

A three dimensional nonlinear finite element model has been developed to study the behaviour of composite beams with profiled sheeting oriented perpendicular to its axis. The analysis of the push test was carried out using ABAQUS/Explicit with slow load application to ensure a quasi-static solution. Both material and geometric nonlinearities were taken into account. Elastic-plastic material models were used for all steel components and the Concrete Damaged Plasticity model was used for the concrete slab. The post-failure behaviour of the push test was accurately predicted, which is crucial for realistic determination of shear capacity, slip and failure mode. The results obtained from finite element analysis were verified against the experimental push tests conducted in this research and also from other studies. After validation, the model was used to carry out an extensive parametric study to investigate the effect of transverse spacing in push tests with double studs placed in favourable and staggered positions with various concrete strengths. The results were also compared with the capacity of a single shear stud. It was found that shear connector resistance of pairs of shear connectors placed in favourable position was 94% of the strength of a single shear stud on average, when the transverse spacing between studs was 200 mm or more. For the same spacing, the resistance of staggered pairs of studs was only 86% of the strength of a single stud. The strength of double shear studs in favourable position was higher than that of the staggered pairs of shear connectors.     

Behaviour of embedded steel plate in composite coupling beams

Plate-reinforced composite (PRC) coupling beam is fabricated by embedding a vertical steel plate into a conventional-reinforced concrete coupling beam to enhance its strength and ductility. Shear studs are welded on the steel plate surfaces to allow for proper load transfer between the concrete and steel plate. The present study focuses on the evaluation of internal load distributions and load sharing on the embedded steel plate as well as at the shear studs in composite coupling beams using the nonlinear finite element package ATENA. The proposed two-dimensional finite element model is able to simulate the overall load-deflection behaviour and internal load distributions of coupling beams subjected to bending and shear forces. The reliability of the model is demonstrated by comparisons with the available experimental results. This is followed by an extensive and carefully planned parametric study using the calibrated finite element model. Numerical results on the effects of steel plate geometry, span-depth ratio of beams and steel reinforcement ratios at beam spans and in wall regions are presented and discussed in this paper. The finite element model provides a better understanding of the behaviour of shear studs as well as plate anchorage in the wall regions and embedded beam region. Based on the numerical results, equations for quantifying the shear stud forces are established and a set of non-dimensional design charts for determining the internal forces of the embedded steel plates is constructed. Both of them are useful for engineers to design PRC coupling beams.     

Modelling semi-rigid composite joints with precast hollowcore slabs in hogging moment region

In this paper, using the general purpose software ABAQUS, a three dimensional (3-D) finite element model was built to simulate semi-rigid composite connection with precast hollowcore slabs. 3D continuum elements are used for all parts of the composite connections and the contact conditions between all the components are explicitly modelled. The model also incorporates nonlinear material characteristics and non-linear geometric behaviour. A simplified method to simulate the bolted end plate connection is introduced and validated. The proposed simulation method of the longitudinal shear transmission can accurately simulate the plastic state of the longitudinal rebars after cracking. Different materials are chosen by the authors to simulate the concrete slab, and the elastic-plastic material property is adopted which can accurately simulate the moment-rotation response of the connections. Numerical results are presented and compared with the experimental data and good agreement is obtained.