首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到17条相似文献,搜索用时 125 毫秒
1.
受火侵袭波纹腹板钢梁的侧向弯扭屈曲及其参数分析   总被引:1,自引:0,他引:1  
王传慧  席丰 《地震学刊》2012,(1):117-123
基于ANSYS的有限元数值计算,考查了简支波纹腹板钢梁在火灾作用下的侧向弯扭屈曲。通过与平腹板钢梁的临界温度作比较,研究了波纹腹板钢梁分别在纯弯矩和集中载荷作用下的抗火性能,并分析了栽荷比、初始缺陷等因素对波纹腹板钢梁抗火性能的影响。分析表明,波纹腹板钢梁与平腹板钢梁在火灾作用下有相同的侧向弯扭屈曲性能。  相似文献   

2.
高温下受弯钢梁的弹塑性弯扭屈曲分析   总被引:1,自引:0,他引:1  
基于弹塑性理论,通过建立钢梁截面的弯矩曲率关系作弯矩作用平面内的弹塑性分析等几个步骤,对火灾高温作用下受弯简支钢梁在弹塑性阶段的弯扭屈曲性能变化进行了分析,给出了钢梁的临界屈曲弯矩的计算表达式。通过算例分析了钢梁弹塑性阶段临界屈曲弯矩随温度的变化,并利用ANSYS有限元软件模拟了钢梁在火灾燃烧不同时刻的竖向变形。结果表明,随着温度的升高,钢梁弹塑性阶段的临界弯矩呈现出逐渐降低的趋势,而其竖向变形则逐渐增大,文中对这2个变量在不同温度条件下的具体变化情况分别进行了详细的分析和描述。  相似文献   

3.
位于冷弯薄壁型钢构件腹板的槽孔,可延长构件两边的热量传递路线,减弱冷弯薄壁钢构件作为墙板龙骨引起的冷桥效应。常温下冷弯薄壁构件的屈曲破坏模态已非常复杂,包括整体屈曲、局部屈曲和畸变屈曲等,且不同的屈曲破坏模态可能会相互影响。火灾下冷弯薄壁构件的破坏机理将更为复杂,根据常规的稳定理论难以求解其火灾下的临界荷载。本文利用有限元方法对火灾下腹板开槽冷弯薄壁卷边槽钢的受力性能进行了模拟,研究了单元类型、材料模型、初始几何缺陷以及求解方法等因素对分析结果的影响,为同类构件抗火性能的有限元模拟分析提供了建模依据。  相似文献   

4.
本研究系统地对低硬度橡胶隔震支座的材料及力学性能进行了试验研究。研究用低硬度橡胶天然及铅芯橡胶隔震支座18种规格总计近30个大直径隔震支座。研究内容涉及低硬度橡胶隔震支座的基本力学性能,温度、压力、剪切变形、老化及徐变等相关性能,压缩界限、拉伸界限、极限剪切变形等界限性能和屈曲特性,以及橡胶材料性能和隔震工程应用等方面。本文主要介绍低硬度橡胶天然及铅芯隔震支座的压缩、拉伸、剪切等界限性能和屈曲应力与剪切应变的相关特性,文中提出了基于刚度因子建立的橡胶支座的界限压缩和界限拉伸应力评价方程,同时还给出了剪切变形状态下的屈曲应力评价方法。  相似文献   

5.
利用腹板屈曲后强度,可以充分发挥钢材的性能,降低钢材用量。为检验利用柱腹板屈曲后强度的钢框架节点板域的抗震性能,设计了边柱和中柱节点,对其进行了低周反荷载下的试验,本文介绍了试验概况,分析了试验结果。  相似文献   

6.
结合两边连接及波纹钢板的优点,提出一种新型的侧边加劲波纹钢板墙。建立了侧边加劲波纹钢板墙的有限元精细化分析模型,采用有限元软件ANSYS对其进行抗剪屈曲分析,推导了波纹钢板墙的弹性抗剪屈曲强度。研究了墙板参数、波纹参数及加劲肋参数对屈曲模态和抗剪屈曲承载力的影响规律。研究结果表明,所提出的波纹钢板墙,其抗剪屈曲承载力较平钢板墙显著提高;在不同的参数下具有整体屈曲和局部屈曲两种不同的屈曲模态;其临界剪切屈曲应力值随跨高比的增加而大致保持不变,随高厚比的增大而逐渐减小,随波纹倾角及子板宽的增大皆先增大后减小。因此,实际工程应用中应合理选择波纹钢板墙参数,以避免发生局部屈曲而导致角部连接失效以及不稳定承载,从而使之具有较大的弹性屈曲承载力,更好地发挥钢材的强度和延性。  相似文献   

7.
运用有限元ANSYS软件和欧洲规范EUROCODE3给出的钢材在高温环境下的热物理及力学特性参数,建立了3个不同顶底角钢厚度的带双腹板顶底角钢梁柱连接的有限元分析模型。运用热-力耦合分析方法,对双腹板顶底角钢梁柱连接在高温下的抗火性能进行了深入研究,探讨了顶底角钢厚度变化对连接在高温环境下受力机理以及螺栓预紧力受温度影响的规律,所得结果对该类节点的抗火设计具有一定的参考价值。  相似文献   

8.
钢框架厂房火灾后的破坏形态   总被引:1,自引:0,他引:1  
端部约束不同的构件在火灾中的破坏形态不同,研究整体结构构件在火灾中的破坏形态,可以为钢结构抗火研究与设计提供依据。某钢结构框架厂房发生火灾,大火历时3个多小时,火场最高温度达1000°C以上。火灾后,框架梁均有不同程度的破坏,钢梁端部下翼缘屈曲破坏较普遍;由于钢梁顶没有设置抗剪键,钢梁与顶部的混凝土现浇楼板脱开,火灾后残留有较大的挠屈变形;钢柱在火灾后未有明显的破坏现象,但有侧向变形产生。这些现象与实验室中标准试验的结果不同。  相似文献   

9.
刘淼鑫  魏路  伍阳  钟维浩 《华南地震》2014,(Z1):148-152
以某实际高层框筒结构工程为例,根据规范设定较高的抗震性能目标,研究分析屈曲约束支撑体系对提高结构的整体抗震性能的效果。分别进行多遇地震作用下的弹性反应谱分析和罕遇地震作用下的推覆分析,结果表明:加设屈曲约束支撑后结构的抗震性能得到明显加强。在多遇地震作用下,屈曲约束支撑体系减小层间位移角;在罕遇地震作用下,屈曲约束支撑体系有效耗散地震能量,减小主体结构变形和损伤,形成合理的整体型结构屈服机制。  相似文献   

10.
升—降温全过程中约束钢梁的有限元与试验分析   总被引:1,自引:0,他引:1  
以轴向支撑连接方式,利用自制的加热炉对约束钢梁进行了升—降温全过程的试验研究。重点研究了钢梁的跨中挠度随温度变化的规律,以及梁端不同轴向支撑刚度和钢柱不同轴压比条件下约束钢梁的屈曲模式及其梁端轴向支撑的破坏形态。基于ANSYS有限元软件,采用温度场和结构耦合中的间接法,对升-降温全过程中的约束钢梁进行了有限元分析。数值计算结果与试验结果吻合较好,验证了有限元模型和参数设置的合理性。根据对比分析,讨论了我国现行钢结构防火技术规范中存在的关键问题,特别提出了钢结构抗火设计应有的内涵,为钢结构抗火研究提供了新的思路。  相似文献   

11.
钢板组合剪力墙在强震作用下受损严重,震损修复问题较为突出。现设计一片以方钢管作为边缘约束构件的竖波钢板组合剪力墙,在最大弹塑性层间位移角时的震损情况进行分析:竖波钢板组合剪力墙边缘约束方钢管刚度较大,与墙体不匹配,最终发生方钢管从地梁拔动的脆性破坏模式。对竖波钢板组合剪力墙进行震损修复,得到墙趾可更换竖波钢板组合剪力墙,然后进行拟静力试验。试验结果表明:(1)在震损后的竖波钢板组合剪力墙的墙趾处安装阻尼器,其抗震性能基本得到恢复。(2)修复后的竖波钢板组合剪力墙承载力较修复前降低了23%,但延性和耗能能力显著提升。(3)改变了竖波钢板组合剪力墙的破坏模式,由脆性破坏转化为延性破坏。借助有限元软件详细讨论了内嵌竖向波形钢板厚度和波角、轴压比、阻尼器腹板数量对修复后竖波钢板组合剪力墙抗剪承载力的影响,结果表明:改变内嵌竖向波形钢板厚度对试件抗剪承载力影响较大,而改变内嵌竖向波形钢板波角、轴压比和阻尼器腹板数量对试件抗剪承载力影响较小。结合有限元算例,提出修复后竖波钢板组合剪力墙抗剪承载力的计算公式,可为工程实际提供参考。  相似文献   

12.
SRC框格复合墙是在普通RC密肋复合墙基础上结合型钢混凝土概念而提出来的一种复合墙板,以轻钢龙骨代替框格内原有纵向受力钢筋,通过焊接或螺栓连接在梁柱轻钢龙骨节点处实现刚性或半刚性连接.在SRC框格复合墙模型试验基的础上,利用ANSYS程序对墙体受力过程进行了非线性有限元分析,提出了SRC框格复合墙抗剪承载力的实用计算公式,并对框格含钢率、轻钢强度等影响因素进行了有限元分析.研究结果表明:所提出的SRC框格复合墙抗剪承载力计算公式,与非线性有限元计算结果吻合较好,能够适应框格含钢率等不同因素变化的计算精度要求;提高肋梁中轻钢强度或含钢率可以有效提高墙体抗剪承载力,而不宜单独采用提高混凝土强度的方法.  相似文献   

13.
A gusset plate is subjected to forces induced from a buckling‐restrained brace (BRB) and frame action. In this study, a performance‐based design method of the gusset connections incorporating a BRB and frame actions is investigated. The force demands resulting from the BRB axial force are computed from the generalized uniform force method. The force demands induced from the frame action effects primarily result from beam shear. A conservative method, which considers the beam axial force effect and the thereafter reduced beam flexural capacity possibly developed at the gusset tips, is adopted in estimating the maximum beam shear. An improved equivalent strut model is used to represent the gusset plate subjected to the frame action effect. The total force demands of the gusset connection are combined from the BRB force and the frame actions. For design purposes, the stress distributions on the gusset interfaces are linearized. The maximum von Mises stress combining the normal and shear stresses is considered as the demand for the gusset plate design. In order to verify the effectiveness of the proposed design method, experiments on a two‐story full‐scale buckling‐restrained braced frame (BRBF) were performed. The chevron and single diagonal brace configurations were arranged in the second and the first stories, respectively. Two different corner gusset connection configurations including one single corner gusset and one coupled corner gusset connection, where two braces in adjacent stories joined at the same beam‐to‐column joint, were tested. The BRBF specimen was subjected to cyclically increasing lateral displacements with a maximum frame drift of 0.04 rad. The maximum story drifts reached 0.035 and 0.061 rad. in the first and the second stories, respectively. At the end of the tests, no fractures were observed on any of the gusset interfaces. Along the gusset interfaces, the normal and shear stress distributions computed from the proposed design procedures and the FEM analysis correlated well with the experimental results. This paper concludes with the procedure and recommendations for the performance‐based design of gusset connections. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

14.
An experimental investigation of the cyclic shear behaviour of steel box girders was conducted on one‐quarter scale models, comprising of two specimens with longitudinally unstiffened webs and one specimen with longitudinally stiffened webs. All the specimens exhibited ductile behaviour. The tests evidenced significant increases in the shear strength and energy dissipation capacity regarding the use of thicker webs and the provision of longitudinal web stiffeners. The web stiffeners also enhanced the stable hysteresis behaviour without substantial degradation in the energy dissipation due to pinching. The test results are compared with the shear behaviour simulated by inelastic large deformation analysis incorporated with a sophisticated constitutive model. The hysteresis behaviour, peak cyclic shear stresses, energy dissipation, and deformation shapes of the three specimens are satisfactorily predicted by the analysis. It is verified that the presented analytical method can be used precisely for further investigations of box girders in shear. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

15.
为研究方钢管混凝土柱-H型不等高钢梁框架节点的抗剪承载力,分析其破坏机理,建立适用于不等高钢梁节点的抗剪计算模型,提出了节点的抗剪承载力计算公式,比较了基于不同抗剪模型建立的抗剪承载力计算值与试验值的差异性。结果表明:节点域的破坏模式主要为上核心区的剪切斜压破坏;节点域抗剪承载力主要由钢管腹板、核心区混凝土主斜压杆及约束斜压杆共同承担。对比分析表明:提出的节点屈服抗剪承载力和极限抗剪承载力理论公式计算值更为接近试验值,验证了方钢管混凝土柱-不等高钢梁框架节点传力机理和承载力计算公式的正确性。  相似文献   

16.
A new buckling restrained braced frame system is proposed for reinforced concrete building structures, which is featured by the zigzag configuration of the braces and the corresponding connection details. The connection details tend to separate the vertical and horizontal components of force imposed by the braces to be resisted by independent structural components to make the behavior of the connection easier to estimate and control. The performance of the brace connection details was evaluated through cyclic load testing on 1/2‐scale subassemblies of the proposed system, each of which consisted of a reinforced concrete part and a set of buckling restrained braces. To simplify the test control, the specimens were rotated 90° in the test and were loaded by two displacement controlled actuators. The test results show that the normal and the shear resistance of the gusset plate connection are essentially independent of each other. However, the rotation of the gusset plate with respect to the beam‐to‐column joint may result in nonuniform force distribution of the anchor bolts, the primary resistance for tensile force. At the same time, such rotation may also subject the concrete corbels, the primary shear resistance, to unfavorable tensile force. In addition, it is also confirmed that the buckling restrained braces performed well in the proposed system. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

17.
This study details a new moment connection that overcomes difficulties in achieving field‐weld quality and eliminates steel beam buckling encountered in steel moment connections. This study presents cyclic test and finite element analysis results of full‐scale subassemblies using steel reduced flange plates (RFPs) to connect steel beam flanges and the column without any other direct connection. Since the RFP connection is designed as strong column‐strong beam‐weak RFPs, the RFP functions as a structural fuse that eliminates weld fractures and beam buckling. Test and analytical results show that (1) the connections transferred the entire beam flexural strength to the column and reached an interstorey drift of 4% with minor strength degradation, (2) failure of the connections was owing to buckling or fracturing of the RFP and not of the beam, and (3) the RFP connection subassembly, modelled using the nonlinear finite element computer program ABAQUS, exhibited hysteretic behaviour similar to that of the flange plate (FP) moment connection subassembly. The inelastic buckling force of the RFP was also evaluated by nonlinear regression analyses performed on a nonlinear model that relates buckling force to RFP geometries. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号