连续正交异性板模型在楼板抗振设计中的应用

将双向多跨连续楼板简化为有限数量的正交异性板，提出一种简化的连续正交异性板模型，有限元动力分析与现场实测结果表明：简化连续正交异性板模型能够较好地模拟连续梁板组合楼盖动力学特性，所得设计结果精确可靠，设计过程简便易行，适于在工程中推广应用。     

基于分条壳单元模拟带压型钢板组合楼板抗火性能

火灾下带压型钢板组合楼板的温度分布较为复杂,其平面内的力学性能各向异性,这给组合楼板有限元模拟带来了很大的难度。基于分条壳单元模型,采用不同厚度的壳单元分别模拟组合楼板板肋厚板和肋间薄板,通过与常温和高温试验结果的对比,对分条壳单元模拟组合楼板的准确性和有效性进行验证。结果表明:该模型可用于组合楼板的传热-结构耦合分析,板肋形状和腹板对组合楼板常温和高温力学性能的影响较大,纵向钢筋的位置对组合楼板抗火性能影响较大,常用的均布钢筋层分析方法会导致偏不安全的结果。     

悬索桥静动力特性分析的有限板壳单元法

本文提出一种基于正交异性板壳单元悬索桥静动力分析方法，以实际工程为例。分别按梁单元模型与正交异性板壳单元模型对其进行了静力与动力分析，并对计算结果进行了详细的比较分析。计算表明，正交异性板单元模型克服了梁单元模型中存在的问题，对大跨度悬索桥整体动力性能与局部的静力性能都能做出更加精确的模拟计算。     

大跨度钢筋混凝土空间曲面板壳结构分析及设计

成都大慈寺文化商业综合体项目中酒店一层中庭楼板造型复杂,为保证建筑功能和美观要求,采用大跨度钢筋混凝土空间曲面开洞板壳结构形式。楼板设计采用细化弹性有限元线性分析和分层壳单元非线性分析。     

基于等效模型的波形钢腹板渡槽结构静力性能研究

淠河总干渠渡槽工程采用桁架式梁拱组合体系,主跨跨径达到110 m。槽身侧壁挡水板采用波形钢腹板。针对波形钢腹板结构,目前多采用建立三维精细化板壳模型的方法开展其结构性能研究,建模过程繁琐且计算效率较低。基于刚度等效原理提出一种将三维波形钢腹板简化为二维正交异性平钢板的等效分析方法。首先建立渡槽工程三维波形钢腹板精细化模型及采用简化方法等效的正交异性平钢板模型,然后开展自重和水荷载下结构静力性能分析,最后对比分析两类模型的静力分析结果及相对误差。研究表明:等效平钢板模型与三维精细化板壳模型计算结果吻合较好,等效分析方法具有较高的准确性和可靠性,可为波形钢腹板结构提供一种简便的分析方法,并显著提高计算效率。     

横隔板缺口形式对正交异性钢桥面板疲劳性能的影响研究

以梯形及矩形截面形状的纵向加劲肋组合3种缺口类型的横隔板,建立正交异性闭口加劲钢桥面板有限元实体模型进行加载,用ANSYS程序计算分析了横隔板不同缺口形式的正交异性钢桥面板力学性能、正交异性钢桥面板、纵肋、横隔板三者连接处的应力状态以及不同缺口形式的正交异性钢桥面板疲劳性能,研究了横隔板缺口形式对正交异性钢桥面板静力力学性能以及疲劳性能的影响。     

公轨两用钢桁梁斜拉桥桥面系横隔板疲劳性能分析

传统正交异性钢桥面板中横隔板与U肋交叉处疲劳损伤严重,公轨两用钢桁梁斜拉桥的板桁组合桥面系上横梁横隔板与上弦杆相接处存在与该构造细节类似的情况.本文基于空间板壳有限元模型,对板桁组合桥面系三个不同位置的横隔板与上弦杆相接处进行疲劳计算,研究其疲劳性能.计算结果表明,该处结构细节的剪应力幅主要由公路荷载引起,正应力幅主要...     

中柱失效工况下钢框架结构倒塌全过程分析

正本文选取钢框架结构为研究对象,考虑了材料的损伤性能以及组合楼板中各组件之间的复杂接触行为,采用ABAQUS建立了压型钢板组合楼板钢框架结构精细化有限元模型;同时以中柱失效工况为例,对其进行了全过程倒塌分析,揭示了钢框架结构抗连续倒塌受力机理,分析了各部件在倒塌过程中的抗力机制。1ABAQUS有限元模型建立本文将结合压型钢板组合楼板梁板子结构的壳-实体有限元模型对ABAQUS有限元建模方法、非线性材料     

大纵肋正交异性组合桥面板混凝土结构层的有效宽度研究

大纵肋正交异性钢桥面板在疲劳性能和经济性等方面具有突出优势,但局部强度不足的问题突出,在钢桥面板上设置混凝土结构层而发展的大纵肋正交异性组合桥面板,是有效改善新型大纵肋正交异性钢桥面板关键疲劳易损部位抗疲劳性能的新型结构体系。大纵肋正交异性组合桥面板在剪力滞效应的影响下,混凝土层纵向应力沿横向分布不均匀,有效宽度是该类结构设计和计算的基本参数。文章建立大纵肋正交异性组合桥面板参数化有限元模型,研究荷载形式、刚性铺装厚度、刚性铺装材料强度、跨中横隔板等因素对混凝土结构层在弹性极限状态下有效宽度的影响。研究结果表明:在不同的加载模式下,有效宽度沿梁跨表现出不同的变化规律;混凝土强度等级和混凝土厚度对有效宽度的影响不显著;跨中设置横隔板能够在一定程度上改善横隔板附近区域混凝土结构层的剪力滞效应。     

城轨钢箱梁U肋正交异性钢桥面板疲劳应力的 正交化计算方法

针对城轨钢箱梁正交异性桥面板关键构造疲劳应力问题,基于有限元方法提出正交化计算方法。首先计算典型正交异性钢桥面构造疲劳应力在城轨A型车和B型车作用下的纵向影响范围及最不利加载位置,并分析减振垫、吊点横隔板、轨下纵梁和道床板等参数的影响。然后根据大量工程实桥设计参数统计提出轨道交通桥梁正交异性板钢箱梁基准计算模型,并建立基准计算模型的空间有限元模型,通过数值计算得到顶板厚度、横隔板高度、横隔板间距、轨下纵梁高度及2种常见开孔形式等关键设计参数的影响系数,基于正交化方法提出不同设计参数条件下正交异性桥面板结构细节的疲劳应力计算公式。最后通过算例验证了正交化计算方法的可靠性和适用性。结果表明:城轨A型车在疲劳荷载作用下结构受力最不利; 轨下纵梁刚度对疲劳应力有显著影响。     

Seismic behavior of tall buildings using steel–concrete composite columns and shear walls

For the seismic design of tall building structures, the behavior under severe earthquakes should be carefully considered and the upper limit of inter‐story deformations are often defined by the design codes. To improve the performance of structures under severe earthquakes, composite structural members, including steel reinforced column and steel plate reinforced shear wall, are often adopted. In the present work, the seismic behavior of tall buildings using steel–concrete composite columns and shear walls is investigated numerically. Fiber beam–column element models and multilayer shell models are adopted to establish the finite element model of structure, and the material nonlinearities are described by the plasticity and damage models. The accuracy of the developed models is verified by the experimental results of a single shear wall. Systematic numerical simulations are performed for the tall building structures subjected to different earthquakes. The comparative study indicates that the nonlinear redistribution of internal forces plays a very important role for the performance of tall buildings under severe earthquakes.     

高层建筑结构分析中对楼板的模型简化

在复杂高层建筑结构分析中,对楼板的模型简化至关重要.本文从工程实用角度出发,对楼板给出了多种简化假定,并在高层建筑结构空间有限元分析与设计软件SATWE中实现了这些假定.在使用中可根据工程实际需要,灵活应用.SATWE软件还具有弹性楼板单元自动划分.自动生成各节点主从隶属关系等功能,从而可大大提高复杂高层建筑结构的分析精度和分析效率.     

Inelastic behaviors of steel shear tab connections

Inelastic behaviors of shear tab connections commonly used in modern steel buildings are investigated in this work. Full‐scale steel shear tab connections with and without concrete slab physically tested by other researchers are closely simulated by non‐linear finite element (FE) method. Different nonlinear FE features (inelastic materials, surface‐based contacts and large geometric options) are included, and different solution strategies (Newton method and Explicit Dynamic method) are employed to balance computational effort and solution accuracy. The simulations extend our understandings on shear tab connections at micro levels, including stress distribution in the connection zone, movement of the neutral axis along the beam sections and normal stress distributions along steel shear tabs and concrete slabs. It is found that the shear tabs contribute to flexural strength of the beam‐to‐column connection and the elastic–plastic theory explains the observed behavior well only when concrete slab is not present. The composite steel shear tab connections have unsymmetrical behavior under negative and positive bending moments. The compressive concrete slabs significantly increase the flexural stiffness and strength of composite shear tab connections. It is also verified that the shear studs near steel columns play a key role for the composite connections. Copyright © 2013 John Wiley & Sons, Ltd.     

高层建筑楼板水平地震内力的计算

复杂体形高层建筑,阴角部位的楼板常发生较严重的震害,其抗震分析应该包含楼板水平地震内力的计算。地震区的简单平面高层建筑,哪些情况可以采用装配式楼板,也需要通过楼板接头的抗震强度验算来判定。本文提出“串并联多质点系”力学模型及相应的数学模型,给出在地震作用下高层建筑各层楼板水平变形和内力的通用计算方法。此外,还选取了一定数量的框-墙结构高层建筑实例,对可能影响楼板水平剪力数值的各种因素,进行了系列的地震反应分析。     

多层、高层建筑结构弹塑性动力、静力分析

应我国高层、超高层建筑发展需要,我们对建筑结构弹塑性动力反应分析软件进行了探索研究,在“高层建筑结构空间有限元分析与设计软件SATWE”的基础上,开发了一套简单实用的建筑结构弹塑性动力、静力分析软件EPDA。目前的EPDA软件提供了两种弹塑性分析方法,一种是弹塑性动力时程分析法,其力学模型有三种:层模型、平面模型和空间模型;另一种是弹塑性静力分析方法,就是通常所说的静力推覆分析方法。EPDA软件是我国第一套商品化的弹塑性分析软件,可以按任意给定方向计算结构的弹塑性时程响应,适用于各种材料的高层及超高层建筑结构,包括钢筋混凝土结构、钢结构和钢与混凝土混合结构,同时,程序中还考虑了多塔、转换层等结构特性。EPDA软件具有如下特点:(1)前后处理功能强,自动读取SATWE和Sat2000的设计分析结果,对钢筋混凝土构件,给出自动选筋结果,用户可以交互修改成实配钢筋;(2)采用纤维束模型模拟梁、柱、支撑等一维构件,纤维束模型的适用性好,不受截面形式和材料限     

压型钢板-混凝土组合楼板抗火性能非线性分析

压型钢板-混凝土组合楼板是目前广泛运用的一种新型结构构件,但由于缺乏对组合楼板抗火性能的研究,现有设计方法并没有充分发挥材料的性能。本文在建立室内火灾传热模型基础上,在空间上运用有限单元法和在时间上运用有限差分的混合解法,编制计算程序解算出火灾下组合楼板在不同时刻的温度场,进而利用钢筋混凝土非线性有限单元法,对多种工况下组合楼板的抗火性能进行了分析,为组合楼板的抗火设计及研究提供了一定的基础。     

New evaluation and modeling procedure for horizontal shear bond in composite slabs

A new method for modeling the horizontal shear bond in steel deck-concrete composite slabs is proposed. The method considers the slab slenderness as the strength parameter that affects the accuracy of horizontal shear bond modeling. A calculation procedure called the Force Equilibrium method is developed to generate shear bond stress versus end slips relationship (shear bond property) from bending tests. An interpolation procedure is also presented to estimate the shear bond property curves for slabs of varying slenderness using two sets of bending test data. The shear bond property curves are applied to connector elements of finite element models to model the horizontal shear bond behavior in composite slabs. The results of this study show that the shear bond of composite slabs under bending varies with the slenderness parameter, and hence influences the slab strength and behavior, as well as affecting the accuracy of the finite element analyses. The finite element analyses conducted on slabs with different slenderness utilizing a single shear bond property, which are not varied according to the slenderness parameter, may lead to either safe or unsafe results, depending on the geometry of the slabs.     

A novel steel section for concrete-filled tubular columns

In modern structural constructions, concrete-filled steel tubular (CFT) columns have gradually become a central element in structural systems like tall buildings, bridges and so forth. The effective parameters on load carrying capacity of CFT columns are the bond between the steel and internal concrete, local buckling strength of steel tube, creep of concrete and loading conditions of column at connections. Considering these effective parameters, a novel section is suggested which can be used for columns of tall buildings and bridges with large spans. The main characteristic of the suggested steel section is internal longitudinal symmetric stiffeners. In the present study, a comparative investigation into the behavior of this novel section (with circular and octagonal shapes) and the most common used sections of CFT columns has been carried out under axial and cyclic loading. Having verified the finite element modeling, several different analyses have been undertaken. The results of the analyses clearly exhibit the increase in strength and ductility of the suggested novel section under axial and cyclic loading and therefore, its application is recommended in construction practice.     

Experimental and numerical study on restrained composite slab during heating and cooling

In this paper, a series of fire tests on restrained composite slabs, carried out at the University of Manchester, is presented. A total of six composite slabs were tested under different fire scenarios, with different load ratios. The tests were particularly concerned with the variation of internal forces within the slabs during both heating and cooling phases. In addition to the testing programme, two separate nonlinear finite element models have been developed to simulate the thermal and mechanical behaviour of composite slabs during heating and cooling, which is introduced in detail in this paper. In the thermal analysis model, plane elements were adopted to obtain a detailed thermal behaviour. In the structural analysis model, the concrete, steel deck and mesh were simulated by solid elements, shell elements and truss elements respectively. The interaction between the concrete and steel sheet was simplified to spring elements. According to the experimental results and FE modelling, the behaviour of composite slabs was analysed in detail. At last, the parametric study was performed where the effect of concrete strength, steel deck thickness and mesh size was analysed.