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1.
Numerical Simulation of Dynamic Response and Collapse for Steel Frame Structures Subjected to Blast Load 总被引：4，自引：0，他引：4
The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA. The multi-material Eulerian and Lagrangian coupling algorithm was adopted. A flu-id-structure coupling finite element model was established which consists of Lagrange element for simulating steel frame structures and concrete ground, multiple ALE element for simulating air and TNT explosive material. Numerical simulations of the blast pressure wave propagation, struc-tural dynamic responses and deformation, and progressive collapse of a five-story steel frame structure in the event of an explosion near above ground were performed. The numerical analysis showed that the Lagrangian and Eulerian coupling algorithm gave good simulations of the shock wave propagation in the mediums and blast load effects on the structure. The columns subjected to blast load may collapse by shear yielding rather than by flexural deformation. The columns and joints of steel beam to column in the front steel frame structure generated enormous plastic defor-mation subjected to intensive blast waves, and columns lost carrying capacity, subsequently lead-ing to the collapse of the whole structure. The approach coupling influence between struc-tural deformation and fluid load well simulated the progressive collapse process of structures, and provided an effective tool for analyzing the collapse mechanism of the steel frame structure under blast load. 相似文献
2.
The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA.The multi-material Eulerian and Lagrangian coupling algorithm was adopted.A fluid-structure coupling finite element model was established which consists of Lagrange element for simulating steel frame structures and concrete ground,multiple ALE element for simulating air and TNT explosive material.Numerical simulations of the blast pressure wave propagation,structural dynamic responses and deformation,and progressive collapse of a five-story steel frame structure in the event of an explosion near above ground were performed.The numerical analysis showed that the Lagrangian and Eulerian coupling algorithm gave good simulations of the shock wave propagation in the mediums and blast load effects on the structure.The columns subjected to blast load may collapse by shear yielding rather than by flexural deformation.The columns and joints of steel beam to column in the front steel frame structure generated enormous plastic deformation subjected to intensive blast waves,and columns lost carrying capacity,subsequently leading to the collapse of the whole structure.The approach coupling influence between structural deformation and fluid load well simulated the progressive collapse process of structures,and provided an effective tool for analyzing the collapse mechanism of the steel frame structure under blast load. 相似文献
3.
Based on the characteristics of an L-shaped column composed of concrete-filled square steel tubes, the axial compression experiment and nonlinear finite element analysis were carried out to study the mechanical property of the L-shaped column. The load-displacement curve for the L-shaped column, the deflection and load-strain curves for the mono columns were obtained by the axial compression experiment. The results show that the L-shaped column exhibits a flexural-torsional buckling failure mode. The numerical simulation by the finite element analysis shows that the bearing capacity and failure mode are in accordance with those of the axial compression experiment and the feasi- bility of the finite element analysis is proved. For the calculation of the bearing capacity of the L-shaped column com- posed of concrete-filled square steel tubes, an analytical method is proposed based on the theory of the elastic stability and spatial truss model. The results of the analytical method are in good agreement with those of the axial compression experiment and the finite element analysis. 相似文献
4.
采用有限元分析方法考察梁和柱的截面尺寸、角型连接件尺寸、铆钉直径及端距等对节点性能的影响,根据计算得到的弯矩-转角曲线拟合出三参数模型中形状系数n 值的近似计算公式。结果表明,柱翼缘厚度和角型件厚度对节点初始刚度和极限承载力影响显著,梁高和铆钉端距的影响次之。形状系数建议公式计算结果与试验结果吻合较好,可为该类连接节点设计方法提供理论依据。 相似文献
5.
Seismic behavior of diaphragm-through connections of concrete-filled square steel tubular columns and H-shaped steel beams 总被引：1，自引：1，他引：0
Based on the introductions of a type of diaphragm-through connection between concrete-filled square steel tubular columns (CFSSTCs) and H-shaped steel beams,a finite element model of the connection is developed and used to investigate the seismic behavior of the connection.The results of the finite element model are validated by a set of cyclic loading tests.The cyclic loading tests and the finite element analyses indicate that the failure mode of the suggested connections is plastic hinge at the beam with inelastic rotation angle exceeding 0.04 rad.The suggested connections have sufficient strength,plastic deformation and energy dissipation capacity to be used in composite moment frames as beam-to-column rigid connections. 相似文献
6.
Bin Rong Rui Liu Zhenyu Li Changxi Feng Guangchao You Fafitis Apostolos 《天津大学学报(英文版)》2017,23(3):258-266
Finite element analysis and parametric studies were performed to investigate the flexural capacity of the panel zone of diaphragm-through joints between concretefilled square steel tubular columns and H-shaped steel beams.Through the comparisons of failure modes,load–displacement curves,and bearing capacity,it was found that the flexural capacity of the panel zone of diaphragmthrough joints was determined by the tensile action and influence of the web of H-shaped steel beams,and the axial load should be taken into account.The steel tube and the diaphragm were the major parts of the joint that resisted the bending moment.The contribution of in-filled concrete had little influence on the flexural capacity of the panel zone of the joint and could be neglected.According to the results of these numerical studies,a formula that considered the influence of the web of H-shaped steel beams and the axial load was developed based on the yield lines in the diaphragm and the steel tube.The results of the proposed formula were in good agreement with the numerical data of this investigation. 相似文献
7.
文章通过SAP2000程序,建立了半刚性组合节点理论分析模型,采用转动弹簧单元来模拟实际中钢管柱与组合梁的半刚性连接。通过分析比较节点在低周反复荷载作用下的荷载(P)-位移(Δ)关系滞回曲得到,组合节点的承载力、刚度和耗能能力有所提高,耗能较好,但承载力相差不大,所以在正常的施工条件下,应优先选用方钢管。 相似文献
8.
The National Swimming Center built for the 2008Beijing Olympic Games applies the polyhedron spatialframe structure, which is based on the foam physicstheory[1]. Its simple geometry is a square box of 170m×170 m×29 m. It can hold 17 000 people, theroof o… 相似文献
9.
Seismic behavior of steel reinforced ultra high strength concrete column and reinforced concrete beam connection 总被引：1，自引：1，他引：0
To investigate the seismic behavior of connections composed of steel reinforced ultra high strength concrete （SRUHSC） column and reinforced concrete （RC） beam, six interior strong-column-weak-beam connection specimens were tested subjected to reversal cyclic load. Effects of applied axial load ratio and volumetric stirrup ratio on ductility, energy dissipation capacity, strength degradation and rigidity degradation were discussed. It was found that all connection specimens failed in bending in a ductile manner with a beam plastic hinge. The ductility and energy dissipation capacity increased with the decrease of applied axial load ratio or increase of volumetric stirrup ratio. The displacement ductility coefficient and equivalent damping coefficient lay between those of steel reinforced ordinary concrete connection and those of reinforced concrete connection. The applied axial load ratio and volumetric stirrup ratio had less influence on the strength degradation and more influence on the stiffness degradation. The stiffness degraded sharply with the decrease of volumetric stirrup ratio or increase of applied axial load ratio. The experimental results indicate that SRUHSC column and RC beam connection exhibited better seismic performance and can provide reference for engineering application. 相似文献
10.
采用有限元法,全过程分析了考虑长期荷载作用下时构件的应变-荷载曲线。基于有限元模型,分析了长期荷载作用下圆端形钢管混凝土柱的工作机理。结果表明:考虑长期荷载作用影响对圆端形钢管混凝土柱的内力分布、变形有较大影响,对承载力影响不大,且随着高宽比的增大,构件的峰值荷载增大,延性减小。 相似文献
11.
欧智菁俞杰林上顺王金泽 《福建工程学院学报》2019,(6):511-517
以黄桷湾特大桥为工程背景,选取轴压比、梁墩刚度比、系梁布置形式及柱肢混凝土强度等级为设计参数,应用Midas Civil有限元软件构造了20座三跨对称桥梁计算模型。研究E1地震作用下钢管混凝土双肢格构墩连续梁桥主要控制截面参数地震响应,探讨各设计参数对钢管混凝土双肢格构墩连续梁桥抗震性能的影响规律,并对全桥进行优化验证。研究结果表明:轴压比对地震作用下结构内力和位移有一定影响,建议控制在0.15~0.25;梁墩刚度比对结构的抗震性能影响较大,控制在4.08~10.90时结构的内力分布更加合理;核心混凝土的强度在C40~C50时取值较为合理。 相似文献
12.
在冲击荷载作用下,钢框架结构的动态响应是一个复杂的非线性过程。运用ANSYS/LS-DYNA建立了钢框架的三维模型,对冲击荷载作用下钢框架的动态响应和破坏形态进行研究。采取多点积分算法,有效避免沙漏问题,保证计算结果精确。以冲击块与钢框架的碰撞冲击为例,研究了冲击速度、冲击块质量、冲击位置等参数对钢框架在横向冲击作用下动力响应的影响,并分析冲击荷载下钢框架的破坏形态。结果表明:冲击块的质量、速度、冲击位置的增加都会不同程度地加剧钢框架的动态响应;在冲击作用下,高应变主要出现在被冲击柱子的冲击区域、柱脚处和梁柱节点处;冲击荷载下钢框架的破坏形态为整个框架发生侧移,受冲击柱在冲击处翼缘出现局部屈曲,受冲击区域的截面发生弯扭,未受冲击柱出现倾斜。 相似文献
13.
Recent research has shown that circular hollow section (CHS) joints may exhibit non-rigid behavior under axial load or bending.
The non-rigid behavior significantly affects the mechanical performance of structures. This paper is concerned with the parametric
formulae for predicting axial stiffness of CHS X-joints while braces are in tension. The factors influencing the axial stiffness
of CHS X-joints under brace axial tension are investigated, including the joint geometric parameters, the axial force of the
chord, and bending moments of braces in two directions, etc. Effects of various parameters on axial stiffness of CHS X-joints
are examined by systematic single-parameter nonlinear analysis using shell finite element methods. The analysis is implemented
in a finite element code, ANSYS. The observed trends form the basis of the formulae for calculating the joint axial stiffness
under brace axial tension by multivariate regression technique. In order to simplify the formulae, two non-dimensional variables
are introduced. The proposed formulae can be used to calculate the joint axial stiffness in the design of single-layer steel
tubular structures. 相似文献
14.
随着钢结构的发展,钢管搭接节点应用越来越广泛.钢结构中节点受力最复杂,目前对平面K型钢管搭接节点的静力研究有很好的基础.但是在低周往复荷载下节点滞回性能的分析还比较少.采用有限元法对平面K型圆钢管搭接节点在弦杆轴向荷载作用下节点的承载力进行研究,对比分析不同几何参数与节点焊接形式下的极限承载力和破坏形式. 相似文献
15.
魏瑞演 《福建工程学院学报》2002,(2)
在高温 (火灾 )条件下钢结构材料力学性能试验研究的基础上 ,建立高温下钢材的屈服强度 ,极限强度、弹性模量和极限应变等力学性能随温度变化的力学模型 ,利用广义clough模型 ,对平面钢框架进行分析 ,建立高温 (火灾 )条件下框架梁、柱杆件的单元刚度方程。 相似文献
16.
以三跨一联钢管混凝土格构式高墩连续梁桥为研究对象,探讨了梁墩刚度比、缀管布置形式和有无减隔震装置设计参数对格构墩地震响应（墩底轴力、墩底弯矩和墩顶位移）的影响规律。研究结果表明:随着梁墩刚度比值的增大,桥墩的地震响应值先急剧下降之后逐渐趋于平缓减小;缀管布置形式参数对格构墩的弯矩响应值影响较为敏感,而轴力和位移值受其影响较小;减隔震装置对该类桥梁的隔震效果显著,隔震率随梁墩刚度比值的增大而减小。设防烈度等级越高,轴力隔震效果越明显,弯矩和位移的隔震率受设防烈度等级影响较小。该研究可为同类桥梁抗震概念设计提 相似文献
17.
因为异形柱经常承受偏心受压加受扭的复杂受力,所以理论计算比较复杂。本研究使用有限元分析软件ABAQUS对T形截面型钢混凝土柱的抗扭性能进行了数值模拟分析,并考虑混凝土塑性发展探讨不同轴压比与钢骨率对型钢混凝土T形截面柱延性与抗扭承载力的影响。利用已有的实验数据,建立构件的受压有限元模型,通过对比荷载-位移曲线验证有限元材料本构的有效性。建立三组模型分析不同轴压比与钢骨率对构件抗扭力学性能的影响,为今后型钢混凝土异形柱的应用提供参考。 相似文献
18.
19.
通过对填充墙钢框架和同尺寸纯钢框架结构的数值模拟,从两种不同形式的框架结构在单调荷载作用下的荷载——位移曲线、低周反复荷载作用下的滞回曲线、骨架曲线及刚度退化曲线,分析得知填充墙钢框架体系是一种理想的抗侧力体系,其优势表现在该结构的耗能能力、极限承载能力、延性、变形恢复能力及抗侧刚度均优于纯钢框架。 相似文献