抗震工程中的钢-混凝土组合结构体系分析

过去10年里,美国关于钢-混凝土组合结构体系抗震性能的研究显著增多。介绍了最近一系列组合横向抗力体系的研究成果,包括由钢梁和钢管混凝土柱或型钢混凝土柱组成的无支撑框架,带钢管混凝土柱的支撑框架及各种组合、混杂墙结构。相比于一般体系,该体系在正常使用或极限状态下的性能及材料与结构的经济性等方面都有许多优点。此外,介绍由带钢筋混凝土填充墙的部分约束钢框架组成的组合体系的深入研究成果。最后,总结了未来对这些组合体系设计的可能规定。     

国际期刊导读

1抗震工程中的钢-混凝土组合结构体系分析 摘要：过去10年里,美国关于钢-混凝土组合结构体系抗震性能的研究显著增多。介绍了最近一系列组合横向抗力体系的研究成果,包括由钢梁和钢管混凝土柱或型钢混凝土柱组成的无支撑框架,带钢管混凝土柱的支撑框架及各种组合、混杂墙结构。     

北美地区的组合或混合结构

在北美,越来越多的组合或混合结构应用于高层建筑的建造中。本文总结了目前北美地区在该领域内的做法,典型的结构体系分为五大类来介绍:1)由组合柱和混凝土托梁构成的框架;2)由混凝土柱和钢托梁构成的框架;3)由组合巨型柱和钢梁构成的框架;4)对角支撑框架;5)带有钢连梁的组合剪力墙。     

不同类型钢-混凝土组合剪力墙超高层结构抗震性能对比

采用结构分析软件Perform-3D对分别带有内置钢板混凝土组合剪力墙、内藏钢桁架混凝土组合剪力墙以及传统的型钢混凝土剪力墙的框架-核心筒结构进行静力和动力弹塑性分析,研究了三种剪力墙对整体结构的动力特性、位移反应和地震损伤的影响。研究表明,带有三种组合剪力墙的结构整体抗震性能优劣顺序依次为内置钢板混凝土组合剪力墙结构、内藏钢桁架混凝土组合剪力墙结构、型钢混凝土组合剪力墙结构。     

高层建筑中钢-混凝土混合结构的研究及应用进展

钢-混凝土混合结构体系兼有钢结构和混凝土结构的优点,在我国高层及超高层建筑中得到了广泛的应用,加强对高层建筑中组合结构构件及混合结构体系的研究很重。对近年在高层建筑中应用的新型组合构件、新型混合结构体系的研究进行了总结,包括巨型钢-混凝土组合柱、高强混凝土钢板组合剪力墙、高效组合剪力墙、型钢混凝土框架-混凝土核心筒结构...     

钢－混凝土组合结构体系研究新进展

以钢-混凝土组合框架结构和框架-核心筒混合结构为对象,综述了在钢-混凝土组合结构体系方面的一些研究新进展。针对组合框架中楼盖的空间组合作用进行了试验研究,发展了三种组合结构地震反应分析模型,重点讨论了在杆系模型中考虑楼盖空间组合作用的方法,从而实现组合框架结构体系的大规模计算。通过刚度解析和数值分析,对框架-核心筒混合结构体系中框架与核心筒的刚度匹配、位移限值指标的取值进行探讨,并对不同混合结构体系的位移特性、失效模式以及安全性能进行对比,为框架-核心筒混合结构的体系优化提供参考。最后,对组合结构体系的研究进行了展望,建议进一步完善组合结构体系的计算手段及其优化指标。图13表3参17     

地震作用下钢框架混凝土核心筒组合结构体系的抗震性能

钢框架混凝土核心筒组合结构体系是外框架采用钢结构,内筒采用混凝土剪力墙结构,形成钢框架混凝土内筒体系。采用ANSYS有限元软件对25层钢框架混凝土核心筒组合结构体系进行地震作用下的地震响应分析和稳定性分析,得到数据结果表明,该结构体系抗震性能比纯钢框架架结构的抗震性能更加优越。     

广义组合结构及其发展展望

本文对组合结构的发展历史和当前的研究及应用现状进行了综述。根据钢-混凝土组合结构的发展趋势和新材料的不断出现和应用,本文提出了广义组合结构的概念。广义组合结构不仅包括钢和混凝土的组合,而且包括更多新材料的组合,是对传统钢-混凝土组合结构的发展。广义组合结构将不同的材料或构件组合在一起共同工作,在设计时将各组成材料和构件的结构性能进行整体考虑,以最有效地发挥各种材料和构件的优势。此外,还对新型组合构件的研发、组合结构体系的创新、组合加固技术的发展以及组合结构在其他领域内的研究和应用进行了展望。     

半刚性部分组合框架-钢板剪力墙抗震性能试验研究

在钢框架-钢板剪力墙结构体系中,以部分填充混凝土型钢柱替代纯钢柱,形成半刚性部分组合框架-钢板剪力墙体系,为研究其抗震性能,通过一榀缩尺比为1∶3的单跨3层半刚性部分组合框架-钢板剪力墙的拟静力试验研究,并与已有的半刚性钢框架-钢板剪力墙试验做对比,分析了二者承载力、滞回性能、柱变形和破坏模式等方面的差异,同时采用理论对比分析了钢柱和考虑横向系杆作用的部分填充混凝土型钢柱局部屈曲承载力差异,以及横向系杆和部分填充混凝土对钢柱及双重抗侧力体系的作用效应。研究结果表明,该双重抗侧力体系协同工作性能良好,滞回性能稳定,整体位移延性系数可达3.42。以部分填充混凝土型钢替代纯钢柱,抑制了框架柱的局部屈曲和平面外的整体失稳,为内嵌钢板提供了足够的锚固刚度,从而充分发挥了钢板剪力墙的承载能力、延性和耗能能力。相较于纯钢柱框架-剪力墙体系,部分组合框架-剪力墙结构整体位移提高58.6%,一层柱的整体内凹变形角降低40.9%,实现了钢板剪力墙平面内的合理破坏模式,形成了"强框架,弱墙板"、"强柱弱梁"的钢板剪力墙体系。     

多层组合结构住宅的设计与对比分析

设计某6层钢-混凝土组合结构住宅,采用框架结构体系,柱为方钢管混凝土,梁为钢-混凝土组合梁,楼板为压型钢板组合楼板.在承载力水平相同情况下,对钢管混凝土柱和钢柱的用钢量进行对比;分析结构体系中设置中心支撑对结构体系内力及变形的影响;对比设置支撑前后钢管混凝土柱截面尺寸及用钢量的变化.分析结果表明:在结构体系中采用钢管混...     

Composite steel and concrete structural systems for seismic engineering

Research within the United States on seismic engineering of buildings using composite steel/concrete structural systems has increased dramatically in the past decade. This paper summarizes recent research on a number of these composite lateral resistance systems, including unbraced moment frames consisting of steel girders with concrete-filled steel tube (CFT) or steel reinforced concrete (SRC) columns; braced frames having concrete-filled steel tube columns; and a variety of composite and hybrid wall systems. The benefits of these structural systems relative to more common systems include their performance characteristics when subjected to service or ultimate loads, and their economy with respect both to material and construction. In addition, more in-depth research results will be presented on one of these composite systems, consisting of partially-restrained steel frames with composite reinforced concrete infill walls. The paper concludes with a summary of probable future design provisions for these composite systems.     

圆钢管混凝土边框多重组合低矮剪力墙的抗震性能

为了解钢管混凝土边框内藏钢桁架剪力墙这种新型多重组合剪力墙的抗震性能,进行了3个剪跨比为1.0的低矮剪力墙低周反复荷载试验,包括1个普通混凝土剪力墙、1个圆钢管混凝土边框剪力墙和1个圆钢管混凝土边框内藏钢桁架剪力墙;对比分析了3个低矮剪力墙的实测承载力、延性、刚度及其退化过程、滞回特性、耗能能力及破坏特征;使用简化力学模型计算了各剪力墙的承载力,计算结果与试验结果吻合较好。结果表明:圆钢管混凝土边框内藏钢桁架低矮剪力墙的抗震性能比普通混凝土低矮剪力墙显著提高,比圆钢管混凝土边框低矮剪力墙明显提高。     

Analytical behavior of frames with steel beams to concrete-filled steel tubular column

This paper reports the mechanism of composite frames with steel beams connected to concrete-filled square hollow section (SHS) columns. Detailed analysis was carried out on longitudinal stress in steel beams, axial stress distribution in concrete, and concrete stress along the column height and at the connection panel. Parametric studies were conducted to investigate the influence of axial load level, beam-to-column linear stiffness ratio on the structural behavior of composite frames. Simplified hysteretic lateral load (P) versus lateral displacement (Δ) models are proposed for such composite frames.     

Nonlinear analysis of concrete-filled thin-walled steel box columns with local buckling effects

Local buckling of steel plates reduces the ultimate loads of concrete-filled thin-walled steel box columns under axial compression. The effects of local buckling have not been considered in advanced analysis methods that lead to the overestimates of the ultimate loads of composite columns and frames. This paper presents a nonlinear fiber element analysis method for predicting the ultimate strengths and behavior of short concrete-filled thin-walled steel box columns with local buckling effects. The fiber element method considers nonlinear constitutive models for confined concrete and structural steel. Effective width formulas for steel plates with geometric imperfections and residual stresses are incorporated in the fiber element analysis program to account for local buckling effects. The progressive local and post-local buckling is simulated by gradually redistributing the normal stresses within the steel plates. Two performance indices are proposed for evaluating the section and ductility performance of concrete-filled steel box columns. The computational technique developed is used to investigate the effects of the width-to-thickness ratios and concrete compressive strengths on the ultimate strength and ductility of concrete-filled steel box columns. It is demonstrated that the nonlinear fiber element method developed predicts well the ultimate loads and behavior of concrete-filled thin-walled steel box columns and can be implemented in advanced analysis programs for the nonlinear analysis of composite frames.     

Nonlinear behavior of concrete-filled stainless steel stiffened slender tube columns

This paper investigates the nonlinear behavior of concrete-filled high strength stainless steel stiffened slender square and rectangular hollow section columns. The stiffened slender tubes had overall depth-to-plate thickness (D/t) ratios ranging 60–160. The concrete strengths covered normal and high-strength concrete. The investigation focused on short axially loaded columns. A nonlinear finite element (FE) model has been developed to study the behavior of the concrete-filled stiffened tube columns. A parametric study was conducted to investigate the effects of cross-section geometry and concrete strength on the behavior and strength of the columns. The results of the concrete-filled stiffened tube columns were compared with the results of the companion concrete-filled unstiffened tube columns. It is shown that the concrete-filled stiffened slender tube columns offer a considerable increase in the column strength and ductility than the concrete-filled unstiffened slender tube columns. The column strengths obtained from the FE analysis were compared with the design strengths calculated using the American specifications and Australian/New Zealand standards. A design equation was proposed for concrete-filled stainless steel stiffened slender tube columns. It is shown that the proposed modified equation provides more accurate design strengths compared to the American and Australian/New Zealand predictions.     

塑-钢管混凝土短柱力学性能的试验研究

在复式钢管混凝土短柱和塑管混凝土短柱的研究基础上,提出一种新型的组合柱：实心塑—钢管混凝土短柱,即以塑管来取代复式钢管混凝土短柱的外钢管而形成的承压构件。通过改变内钢管的径厚比、外塑管的厚度以及混凝土的强度等级来研究该新型组合柱的基本力学性能,同时还研究了FRP的加固方式对组合柱承载能力的影响,包括组合柱在轴向荷载作用下的宏观变形特征、破坏模式以及荷载和纵向应变的关系。     

Seismic behavior of CFRSTC composite frames considering slab effects

This paper reports on an experimental and numerical investigation conducted on the seismic behavior of concrete-filled rectangular steel tubular columns (CFRSTC) composite frames. The experimental study was conducted by subjecting two full-scale composite frames to simulated seismic loads. Both frames were composed of CFRSTC and steel beams. One specimen was placed on a reinforce concrete (RC) floor slab and the other was not. The purpose of the test was to investigate the elasto-plastic performance of the CFRSTC composite frame system and to examine the effects of composite action on the behavior of composite frames. The test results showed that the stiffness, strength and energy-dissipating capacity of the CFRSTC frame increased significantly with the presence of the floor slab. Compared with a bare steel beam, the composite beam experienced a decrease in the rotation capacity from 0.046 rad to 0.026 rad. The shear deformation of the panel zone grew because of the composite action, which delayed the fracture of the beam. Finite element (FE) models were established to simulate the tested frames. The results of the FE model fit well with that of the test model in terms of stiffness, strength, hysteretic behavior and component deformation.     

Fire resistance of axially loaded concrete filled steel tube columns

The behaviour of axially loaded square and circular concrete-filled steel tube (CFST) columns when exposed to elevated temperatures is investigated in this paper. The fire resistance of this kind of composite tubes is calculated. Comparison of the square and circular columns in the fire resistance shows that, for columns with the same steel and concrete cross-section areas, the circular column has slightly better fire resistance than the square column.     

双钢管混凝土复合柱的耐火性能及参数影响分析

双钢管混凝土复合柱在普通钢管混凝土柱基础上设置了内部钢管,由于内管受到外层混凝土的高温保护,因此其耐火性能得到改善。文章通过精细化数值模拟方法对此类双钢管混凝土复合柱的耐火性能开展研究,全面分析了内管径厚比、外管径厚比、内外管直径比等参数的影响,并且对比分析了在相同的含钢率条件下不同截面组合型式（内圆外圆、内方外圆和内圆外方）双钢管混凝土短柱的耐火极限。结果表明：在直径不变时增大内钢管的厚度以及在厚度不变时增加内钢管的直径,都有利于耐火极限的提高;在保持整体含钢率不变的条件下,不同截面组合形式的双钢管混凝土柱耐火极限相差不大,但总体上双圆钢管混凝土短柱的耐火性能偏优;另外,双钢管混凝土复合柱的耐火性能比普通钢管混凝土柱有较大提高。