膜结构建筑与其它传统建筑结构性能对照优势

优势1.膜结构建筑是一种新型的建筑结构形式。从设计、结构体系及受力形式上完全区别于其他传统建筑结构,它以优良的建筑织物为材料以柔性钢索或钢性支撑结构将其绷紧,从而形成具有一定刚度、张力、能覆盖大跨度空间结构体系,国际超过200m跨度的大型膜结构建筑很多。2.膜结构建筑景观效果最佳,可以充分发挥建筑师的想象,那些曲线曲率是其他建筑达不到的,能充分体现自然美、技术美、艺术美,而且与周围建筑环境相容性很强。     

强降雨作用下具有初始凹陷的充气膜结构袋状效应研究

采用向量式有限元法对强降雨作用下具有初始缺陷的充气膜结构的袋状效应进行了研究.探讨了基于向量式有限元的膜单元内力公式、膜结构初始缺陷施加方式、强降雨模拟方法以及膜结构破坏准则等问题,提出了强降雨作用下膜结构袋状效应研究的基本假定和积水荷载计算方法,建立了膜结构袋状效应分析流程.最后通过编写MATLAB程序,对一正方形充气膜结构在强降雨作用下从袋状效应形成直至结构破坏的全过程进行模拟,验证了本文方法的正确性和有效性.     

随州高铁站ETFE伞状索膜结构分析设计

随州高铁站主体结构采用"伞状单元体"索膜结构,为实现随州高铁站站房中"伞状单元体",提出了一种大曲率索膜协同作用伞状单层ETFE膜结构方案.首先根据建筑方案,提出2种不同的布索方案.采用小弹性模量法对索膜进行协同找形分析,并对预应力态和荷载态下的索膜结构进行计算分析,对比了不同布索方案、不同膜厚度的ETFE膜结构的膜面应力、索力等.研究表明,小弹性模量法适用于单层ETFE与索网协同找形分析,大曲率索膜协同作用ETFE膜结构可用于实际工程,本工程选用布置5道横向索时,索膜结构应力均匀,满足设计要求.     

索膜结构自振特性的温度作用影响研究

研究了不同温度作用下预应力索膜结构的自振特性问题.在建立索膜结构自振特性分析的有限元方法的基础上,对索膜结构自振特性的温度作用影响进行了研究,通过算例分析给出了结构的自振频率、模态,得到了不同温度作用下索膜结构的自振特性规律.算例分析表明温度作用对索膜结构自特性影响不可忽略,研究成果为索膜结构后续的动力分析奠定了坚实的基础.     

索膜结构的二次找形法

本文首先分析索膜结构找形分析的几种主要方法,发现这些方法均没有考虑重力的影响,因此提出考虑重力作用的二次找形法,给出二次找形法的基本原理和计算框图,编制相应的程序,并通过两个算例来验证.算例分析发现,索膜结构在找形分析时,若考虑重力作用,膜面和索的曲率比未考虑重力时大,因此二次找形法获得的结果更接近实际的情况,同时该方法还具有收敛速度快、收敛性好的优点.     

膜结构风致振动响应的数值分析

膜结构属于张拉力结构,质轻而柔且不具有抗弯刚度,外荷载作用下结构的变形比较显著,这些特点决定了膜结构对风荷载十分敏感。利用ANSYS仿真软件对膜结构的流固耦合现象进行分析,研究了结构流固耦合效应的分压分布规律,同时给出具有柔性边界的流固耦合效应。     

预应力索膜结构的温度效应研究

对预应力张拉索膜结构由于温度变化对结构初始平衡形状和静力效应的影响进行研究.考虑温度作用对索膜结构形态和受力特性的影响,在推导索膜结构在温度作用下找形分析和静力分析的非线性有限元方程的基础上,进一步研究温度对索膜结构初始平衡形状和静力特性的作用效应.通过算例分析,探讨不同温度变化作用下的索膜结构初始几何形态、内力和位移的作用效应,并提出工程建议.     

车辐式大跨度张拉索膜结构的风振响应分析

车辐式大跨度张拉索膜结构由于质量轻、刚度相对较弱,对地震作用具有良好的适用性,但对脉动风作用却比较敏感.国内外由动风荷载引起的大跨度索膜结构的破坏也屡见不鲜.本文运用非线性有限元动力时程方法对该类结构进行了参数化分析,其中主要讨论了不同预应力度和膜材张拉刚度对车辐式大跨度张拉索膜结构风振响应的影响,并对动风等效进行了初步分析,得到了可供工程实际参考的动风等效系数.     

离散微分几何在膜结构设计中的运用

基于有限元分析的离散模型,将离散微分几何领域的最新成果运用于膜结构设计,求解曲面曲率,法向量,主方向及测地线,进行结构分析设计。算例表明此方法快速简便,避免多次曲面拟合。     

某地铁站台膜结构平均风压分布系数数值模拟研究

膜结构比较轻柔,为风敏感性结构。膜结构在风荷载作用下的变形和振动会影响到结构表面的风压分布情况,即会产生流固耦合效应。在结构设计中,平均风压分布系数在强度设计中具有非常重要的作用。本文采用通用有限元软件ADINA进行了考虑流固耦合作用的地铁站台屋盖膜结构平均风压分布数值模拟。数值模拟简洁、高效,可以供复杂工程的风荷载设计参考。     

Stability analysis of prestressed space truss structures based on the imperfect truss element

Prestressed space truss structures have been widely used in various public buildings in recent years. However, because of its large span, the length of its members also increases. Therefore the member initial curvature will probably affect the stability of the structure. This paper focuses on the truss element with initial geometrical imperfection under high axial load. The relation between axial force and deformation, the expression of axial tangent stiffness, and the concept of initial curvature coefficient for truss element are established. With the example of prestressed cable-stayed arch-truss structure, the influence of member initial curvature on nonlinear stability performance of the structure under various prestress values is studied. The result indicates that member initial curvature has little influence on global stiffness of the structure before buckling, but has great influence on the performance of the structure after buckling and on limit load of the structure. Under different prestress values, the limit load-member initial curvature curves are parallel and almost linear. The proposed method in this paper can be widely applied into nonlinear stability analysis of various prestressed space truss structures with large span, so that the influence of member initial curvature on structural stability can be estimated.     

圆钢管混凝土结构非线性有限元分析

基于合理的钢管混凝土拉、压材料数值本构模型,采用U.L.列式单元增量平衡方程,引入分层梁单元材料非线性分析理论,通过调整截面形心应变和曲率,使梁端内外力平衡,完善了分层单元法,编制了相应的非线性有限元程序,并对已有钢管混凝土结构面内受力,如钢管混凝土偏压柱、不等端弯矩钢管混凝土偏压柱、钢管混凝土压弯构件和钢管混凝土模型拱肋等试验资料进行双重非线性有限元分析。结果表明:几组钢管混凝土模型拱和钢管混凝土压弯构件的荷载-变形曲线和极限承载力与试验结果最接近,验证了本文方法与程序的可靠性,通过与其他学者计算结果相比,表明本文方法具有较高的计算精度。     

Elasto-plastic stability of single-layer reticulated domes with initial curvature of members

Initial curvature of members is an inevitable geometrical imperfection for reticulated domes. To investigate the stability of single-layer domes with initial curvature of members, the multi-beam method was presented to simulate the initial curvature of members, and two modeling methods were adopted to introduce the initial curvature of members for reticulated domes by means of ANSYS. First, the random imperfection mode method was introduced according to the randomness of initial curvature of members. The example of a Kiewitt-8 dome was used to explain the method and investigate the influence of angle and amplitude random variables on the stability of reticulated domes. Second, the modified consistent imperfection mode method was obtained, which was an efficient method to evaluate the lowest buckling load of the structure with initial curvature of members. Based on this method, the Kiewitt-6 and Kiewitt-8 single-layer reticulated domes were taken as examples to analyze the stability of structures with initial curvature of members, and the influences of initial curvature of members on the ideal structure and the structure with nodes deviation were obtained quantitatively. The results show that, for the ideal structure and the structure with nodes deviation, initial curvature of members can decrease the buckling load of the structure obviously. Initial curvature of members can change the buckling mode and plasticity development of the structure. The influence of initial curvature of members on the elasto-plastic stability of single-layer reticulated domes cannot be neglected.     

张拉膜结构荷载分析过程的若干问题探讨

膜结构是一种柔性结构 ,影响其荷载分析的各要素与砼结构等刚性结构不同。本文在参考国内外文献的基础上 ,结合笔者在膜结构工程设计过程中所积累的经验 ,对与膜结构荷载分析有关的各要素 ,包括荷载种类、荷载组合、初张力、荷载效应等进行了分析 ,为膜结构设计的标准化、规范化做了一定的理论准备工作。     

夹层钢管混凝土梁-柱在循环荷载作用下的性能分析

夹层钢管混凝土(CFDST)在桥梁和建筑的建设中具有很大的潜能。轴力和循环加载的弯曲荷载作用下,弯矩曲率曲线(M-(?)),柱侧向荷载-侧移曲线(P-Δ)模型的研究信息非常有限。建立了一个力学模型,用于分析轴向恒荷载和循环加载的弯曲荷载作用下的CFDST梁-柱。预测的组合梁柱的循环反应性能与试验结果一致。基于这个理论模型,对组合梁柱有关弯矩曲率曲线(M-(?)),侧向荷载-侧移曲线(P-Δ)的性能进行了参数分析。最后,提出了计算弯矩曲率曲线(M-(?)),侧向荷载-侧移曲线(P-Δ)的简化模型。     

Behaviour of curved and continuous compression members

Several modern lightweight space structures utilize curved and continuous compression members, although the behaviour of these members is not well understood. In many cases, the members are subjected to eccentric loading, which creates another difficulty in predicting their behaviour. Understanding the behaviour of curved and continuous members is certainly essential for the accurate modelling of the structures that use them, and for the reliable prediction of their strength, ductility and overall performance. The generic study presented in this paper uses theoretical and nonlinear numerical analyses to quantify the effect of curvature, continuity and load eccentricity on the behaviour of compression members. The work, although fundamental in nature, is of significant benefit to practical designs involving curved compression members.     

考虑悬链线效应的钢筋混凝土框架结构抗连续倒塌能力分析

为了研究悬链线效应对钢筋混凝土（RC）框架结构抗连续倒塌能力的影响,基于OpenSees建立可以考虑悬链线效应的RC框架宏模型,通过两个RC框架子结构在移除中柱后的竖向承载力试验结果对比,验证了所采用宏模型的合理性,并研究了悬链线效应对RC框架子结构抗连续倒塌能力的影响。分别采用备用荷载路径法中的非线性静力方法和非线性动力方法对1栋10层RC框架结构进行抗连续倒塌能力分析,研究悬链线效应对RC框架整体结构抗连续倒塌能力的影响。结果表明：不考虑悬链线效应的影响将低估RC框架结构的抗连续倒塌能力;在移除底层中柱情况下,不考虑悬链线效应分析得到的荷载放大系数最大值小于2.0,而考虑悬链线效应分析得到的荷载放大系数最大值则超过2.0。     

Elasto-plastic analysis of perforated core structures subjected to applied torque

This paper presents a method of analysis, based on Vlasov's thin-walled beam theory in conjunction with the continuum approach, for investigating the elasto-plastic behaviour of perforated core structures subjected to torsional loading. A closed section analogy is utilized in the analysis. It is assumed that the plastic hinges form at the ends of the lintel beams and the lintel beams will fail prior to any yielding of the walls when the limiting rotational ductility is reached. The analysis enables the behaviour of a perforated core structure to be traced from working load to ultimate condition.     

基于曲率模态的钢筋混凝土梁损伤检测研究

阐明了曲率模态的基本原理。对钢筋混凝土简支梁进行逐级加荷-卸荷试验,每次卸荷后进行动态检测试验,用DASP系统对试验数据进行分析,得到位移模态。利用二阶差分法,由位移模态得到了曲率模态。结果表明,曲率模态能较为准确地识别钢筋混凝土简支梁的损伤,且对微小损伤较为敏感,高阶的曲率模态对于损伤的敏感性高于低阶曲率模态。利用曲率模态能够较好地判定损伤的位置以及损伤的相对程度。     

国家自然科学基金委双层膜结构设计

介绍了国家自然科学基金委顶层膜结构的设计计算过程 ,包括薄膜结构的找形设计、荷载分析、裁剪设计 ;钢结构设计及索膜节点设计等。该工程的建成对以后类似的双层膜工程有一定的参考价值。