闭口型压型钢板-混凝土组合板振动特性研究

随着压型钢板-混凝土组合板结构在工业厂房、电厂以及城市桥梁中的应用,组合板振动特性逐渐受到业主和设计人员关注。本文对四种类型共16块两端简支的BONDEKⅡ型闭口型压型型钢板-混凝土组合板进行模态试验,得到了闭口型压型钢板-混凝土组合板第1阶至第3阶自振频率。采用ANSYS程序对四种类型试件进行了数值模态分析,并按现有规程提供方法计算了试件的第1阶自振频率。通过比较模态试验、数值模拟和理论计算三种方法的计算结果。对所采用数值模态分析技术进行了验证。最后进一步对一系列不同跨度和边界条件下的组合板进行数值模态分析,得到不同跨度和边界条件下组合板各阶振型和自振频率,为组合板振动设计提供有益的参考和依据。     

冷弯薄壁型钢-混凝土组合楼盖振动性能试验研究

对构造不同的四块足尺比例冷弯薄壁型钢-混凝土组合楼盖模型进行振动性能的动载试验。在正常使用阶段,研究压型钢板与冷弯薄壁型钢梁连接的螺钉间距、刚性支撑件、楼盖端部约束条件等构造设置和楼面活荷载对组合楼盖自振频率的影响。研究表明:组合楼盖的自振频率随楼面活荷载的增加而降低;减小压型钢板与冷弯薄壁型钢梁连接的螺钉间距、相邻楼盖梁的跨中位置设置刚性支撑件及加强楼盖端部约束均能提高组合楼盖的自振频率。采用ANSYS有限元程序对试验模型24种荷载工况的振动性能进行模态分析,有限元模态自振频率与试验自振频率吻合较好。提出的理论公式能够较好预测组合楼盖的自振频率。在正常使用阶段荷载标准组合下,建议组合楼盖的自振频率不小于10Hz。     

闭口型压型钢板-轻骨料混凝土组合板受力性能及动力特性试验研究

对6块闭口型压型钢板-轻骨料混凝土组合板试件进行了两点对称集中加载静力试验研究,考察了组合板在不同剪跨比下的破坏形态、钢板与混凝土应变发展、端部滑移和裂缝发展情况,研究了组合板的纵向剪切极限承载能力。研究结果表明,端部设置栓钉的闭口型压型钢板-轻骨料混凝土组合板具有较好组合作用,剪跨比较小的闭口型压型钢板-轻骨料混凝土组合板主要发生纵向剪切粘结破坏,而剪跨比较大的组合板主要发生接近于弯曲破坏的弯剪破坏;根据试验研究结果,建立了闭口型压型钢板-轻骨料混凝土组合板的承载能力计算公式,并给出了组合板刚度计算建议方法。为考察组合板的动力特性,对6块闭口型压型钢板-轻骨料混凝土组合板的前三阶自振频率和阻尼比进行了试验测试,测试结果表明闭口型压型钢板-轻骨料混凝土组合板阻尼比比较小,并结合自振频率实测结果对经验计算公式进行了对比验证,为闭口型压型钢板-轻骨料混凝土组合板动力特性计算及组合楼盖的竖向振动分析控制设计提供依据     

压型钢板组合楼盖受力分析及工程应用

压型钢板-混凝土组合结构在工程应用中,通常组合楼盖仅考虑单向受力,本文将压型钢板等价为正交各向异性平板,利用ANSYS中SHELL91单元建立组合板分层壳有限元模型,考虑压型钢板组合楼盖双向受力性能,通过在压型钢板垂直肋上翼缘贯通焊接剪力筋,增强垂直肋方向抗弯性能,利用有限元模型讨论不同约束及跨度比双向组合板弯曲性能。     

某钢管混凝土拱桥自振特性分析

采用有限元软件ANSYS,对一座下承式钢管混凝土桥的自振特性进行了分析。结果表明:该下承式钢管混凝土拱桥主要为桥面及拱肋横向振动、整体竖向振动和扭转振动三种振动形式,且振型越往后越复杂;该桥梁的桥面、拱肋的横向振动以及整体竖向振动、扭转振动,其相邻模态频率几乎接近,与其它该类桥梁大为不相同。另外,通过各种设计参数的改变,对自振特性进行分析,结果发现,考虑自重及改变混凝土弹性模量对结构自振频率影响不大;减少横撑则影响高阶模态振型;矢跨比对其自振频率的影响不大,但对振型的影响却不尽相同。     

大跨度U形钢-混凝土组合空腹夹层板楼盖舒适度实测分析

以贵州省博物馆红军长征馆为例,利用环境激励,采用频域法模态拟合方法对该大跨度U形钢-混凝土组合空腹夹层板楼盖进行了现场竖向振动模态测试和人员作用下的舒适度分析,得到了该楼盖结构前6阶竖向自振频率、振型、竖向加速度时程曲线以及实测加速度的最大值,采用有限元分析方法对实测自振频率和振型进行了对比分析。分析结果表明:模态分析中楼盖竖向第1阶自振频率的有限元分析结果和实测结果均满足现行规范要求;舒适度分析中楼盖竖向峰值加速度实测结果满足规范小于0.005g的要求,不会引起人员不适;由于隔墙和约束的原因导致有限元分析结果与实测结果不一样,但是相差大小在正常范围内。     

压型钢板组合梁滑移性能的有限元分析

利用ANSYS有限元软件对压型钢板组合梁模型进行了有限元数值模拟分析,将有限元分析结果与试验结果进行了比较,验证了模型的合理性,利用ANSYS软件对压型钢板组合梁在栓钉布置方式和混凝土板强度影响下交界面的滑移性能进行了探讨.     

压型钢板-混凝土组合板纵向抗剪性能研究进展

压型钢板-混凝土组合板具有承载力高、自重轻、施工便捷等优点,广泛应用于工业厂房、高层建筑及桥梁中。压型钢板-混凝土组合板的纵向抗剪性能是一个重要的研究方向,通过其对理论研究、试验研究以及数值模拟研究三方面进行梳理,分析了目前国内外压型钢板-混凝土组合板纵向抗剪性能的研究成果。结果表明：目前对组合板的纵向抗剪性能研究主要是以试验与数值模拟相结合的方式,基于试验结果建立的有限元模型,能够有效模拟组合板的受力状况。并基于研究现状,对压型钢板-混凝土组合板进一步的研究方向和思路提出建议,以期对下一步的研究应用提供参考。     

基于ANSYS的人行天桥自振特性分析

为研究人行天桥的自振特性,通过有限元分析软件ANSYS12.1对某人行天桥建立了有限元结构模型,进行了人行天桥的模态分析,通过模态分析得到了人行天桥的自振频率、自振周期、振型等自振特性。数值分析表明:人形天桥结构振型主要以竖弯为主,高阶振型还会出现横移、扭转等变形。     

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。     

闭口型压型钢板——混凝土组合板承载能力试验研究

闭口型压型钢板—混凝土组合板中,压型钢板能更好地起到受拉钢筋的作用,比开口型压型钢板—混凝土组合板有更多性能优势和更好的应用前景。通过八块采用新型BONDEKⅡ型闭口型压型钢板的组合板的静力性能试验研究和理论分析,着重考察剪跨比和组合板端部栓钉布置对组合板受力性能、破坏形态和极限承载能力的影响,提出了该类闭口型压型钢板的组合板的受弯承载力、竖向受剪承载力和纵向剪切粘结破坏承载力的计算方法及公式,为组合板设计计算提供依据。     

闭口型压型钢板-混凝土组合板的受弯性能

闭口型压型钢板可以作为组合楼板中的受力钢筋。为了得到闭口型压型钢板 -混凝土组合板的受弯性能 ,进行了 4块闭口型压型钢板简支组合板的试验。在普通钢筋混凝土板抗弯承载力计算方法的基础上 ,提出了闭口型压型钢板 -混凝土组合板抗弯承载力的计算公式     

闭口型压型钢板-混凝土组合板疲劳性能试验研究

为研究闭口型压型钢板-混凝土组合板的疲劳性能,完成14块闭口型压型钢板-混凝土组合板的疲劳试验研究。试验主要考察组合板端部栓钉布置、组合板板厚、疲劳荷载水平及组合板加载剪跨比等4个主要因素对组合板疲劳破坏模式及疲劳损伤程度的影响。试验过程中对组合板在各个关键阶段的动挠度、动滑移、压型钢板及混凝土应变、组合板残余挠度及组合板剩余承载能力等参数进行测量和分析。在试验研究基础上,根据组合板疲劳破坏形态及损伤发展情况,着重对组合板的疲劳性能进行较全面研究,初步提出组合板疲劳性能水平评估方法及组合板疲劳设计建议。试验研究结果表明,无栓钉组合板的疲劳性能明显差于带栓钉组合板,布置栓钉可大大提高组合板疲劳性能;无栓钉组合板的设计疲劳荷载上限可以取为40%的静力极限荷载,而带栓钉组合板的设计疲劳荷载上限可以取为60%的静力极限荷载。研究结果为闭口型压型钢板-混凝土组合板疲劳设计计算提供有利依据。     

Performance of shear connection in composite beams with profiled steel sheeting

This paper describes the structural performance of shear connection in composite beams with profiled steel sheeting. An accurate and efficient nonlinear finite element model was developed to study the behaviour of headed stud shear connectors welded through-deck. The profiled steel sheeting had transverse ribs perpendicular to the steel beam. The material nonlinearities of concrete, headed stud, profiled steel sheeting, reinforcement and steel beam were included in the finite element model. The capacity of shear connection, load-slip behaviour of the headed stud, and failure modes were predicted. The results obtained from the finite element analysis were verified against experimental results. An extensive parametric study was conducted to study the effects on the capacity and behaviour of shear connection by changing the profiled steel sheeting geometries, the diameter and height of the headed stud, as well as the strength of concrete. The capacities of shear connection obtained from the finite element analysis were compared with the design strengths calculated using the American Specification, British Standard and European Code for headed stud shear connectors in composite slabs with profiled steel sheeting perpendicular to the steel beam. It is found that the design rules specified in the American and British specifications overestimated the capacity of shear connection, but the design rules specified in the European Code were generally conservative.     

Performance and design of shear connectors in composite beams with parallel profiled sheeting at elevated temperatures

This paper describes an extensive experimental and numerical study conducted to evaluate the thermo-structural response of shear connectors embedded in composite slabs with steel sheeting parallel to the steel beam, with particular focus on opentrapezoidal profiles. For this purpose, eight push-out tests were carried out at different levels of temperature. A threedimensional finite element model was developed in Abaqus and its accuracy was validated against the experimental measurements collected as part of this study. The model was then used to perform a parametric study to gain insight into the structural response at different temperatures. The experimental and numerical results were then used to evaluate the accuracy of available European guidelines for predicting the capacity of shear connectors at elevated temperatures (when embedded in composite slabs with the profiled sheeting parallel to the steel beam). Finally, a new design equation was proposed to calculate the degradation factor defining the resistance of shear connectors for different levels of temperature.     

压型钢板-混凝土组合楼板剪切粘结性能研究

为研究YX75-200-600和YX76-344-688压型钢板-混凝土组合楼板的剪切粘结承载力和剪切粘结性能,进行了18块足尺寸简支压型钢板-混凝土组合楼板的载荷试验,并进行了相关的分析。试验结果表明:18个试件的破坏形态均为剪切粘结破坏,影响剪切粘结性能的主要因素有剪跨、压型钢板厚度和栓钉。由试验数据分析得到的端部有栓钉YX75-200-600压型钢板-混凝土组合楼板的剪切粘结系数m,k为228.12,-0.015,YX76-344-688压型钢板-混凝土组合楼板的剪切粘结系数m,k为246.9,-0.0028。     

Behaviour of headed stud shear connectors for composite steel-concrete beams at elevated temperatures

The behaviour of composite steel-concrete beams at elevated temperatures is an important problem. A three-dimensional push test model is developed herein with a two-dimensional temperature distribution field based on the finite element method (FEM) and which may be applied to steel-concrete composite beams. The motivation for this paper is to increase the awareness of the structural engineering community to the concepts behind composite steel-concrete structural design for fire exposure. The behaviour of reinforced concrete slabs under fire conditions strongly depends on the interaction of the slabs with the surrounding elements which include the structural steel beam, steel reinforcing and shear connectors. This study was carried out to consider the effects of elevated temperatures on the behaviour of composite steel-concrete beams for both solid and profiled steel sheeting slabs. This investigation considers the load-slip relationship and ultimate load behaviour for push tests with a three-dimensional non-linear finite element program ABAQUS. As a result of elevated temperatures, the material properties change with temperature. The studies were compared with experimental tests under both ambient and elevated temperatures. Furthermore, for the elevated temperature study, the models were loaded progressively up to the ultimate load to illustrate the capability of the structure to withstand load during a fire. It is concluded that finite element analysis showed that the shear connector strength under fire exposure was very sensitive. It is also shown that profiled steel sheeting slabs exhibit greater fire resistance when compared with that of a solid slab as a function of their ambient temperature strength.     

Analysis of deflections of composite slabs with profiled sheeting up to the ultimate moment

This paper deals with an investigation of the deflections of composite slabs. The deflection of composite slabs depends directly on the shear stiffness of the connection between profiled steel sheeting and concrete. A method for calculating deflections of slabs is presented in this paper. This method is based on a theory of built-up bars, which allows one to take into account directly the shear stiffness of the connection. Influences on the stiffness of the structure of normal cracks in the concrete layer and plastic deformations of concrete that has been subjected to compression are also taken into account in the analysis method. The method gives one an opportunity to assess variations of these factors at all stages of the slab’s behaviour from the start of loading up to the ultimate moment. Results of the experimental investigations of a connection (contact) between steel profiled sheeting (Holorib type) and concrete are presented in this paper. In the results of these investigations, three stages of behaviour of the contact are distinguished. A connection shear characteristic is determined for each stage, which is used for calculating the deflection of the slab.Experimental investigations were performed on deflections of composite slabs with a Holorib type of profiled sheeting. Variations in experimental deflections of slabs were explored from the beginning of loading up to the ultimate moment.Theoretical calculations of deflections for the experimental slabs were made. Calculations were performed according to the method proposed by the authors. A comparison of experimental and theoretical values of deflections revealed that agreement between these values was sufficiently good at all stages of the slab’s behaviour.