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951.
钢管混凝土轴压长柱试验分析   总被引:1,自引:0,他引:1  
本文通过对 3种长度的方形钢管混凝土柱和 2种长度的矩形钢管混凝土柱的试验分析 ,比较了 2种计算柱子轴压稳定系数的方法 ,得出了现行公式能很好地计算方形钢管混凝土柱的轴压稳定系数 ,但对于矩形钢管混凝土柱的轴压稳定系数计算 ,还必须进一步修正。  相似文献   
952.
Two large bolted steel moment-resisting connections were studied by experiments. These connections were single-sided beam-to-column assemblies that are representative of exterior beam-to-column connections, and they were composed of W36×150 Grade 50 beams and W14×283 Grade 50 columns. T-stubs were cut from W40×264 sections of Grade 50 steel. The T-stub stems were welded to the beams and prestressed by bolts to the beam flanges in the shop. Final beam-to-column assembly required no additional welding: the T-stub flanges were bolted to the column and the column shear tab was bolted to the beam web. The specimens had two symmetrically located T-stubs with different stem geometry: Specimen 1 had rectangular-shaped stems, whereas Specimen 2 had U-shaped stems. During the cyclic testing the beam deformation was minimal controlled by active participation of the T-stub flanges: a separation between T-stub flanges and the column flanges was observed. This separation was caused by bending plastic deformation in the T-stub flanges and plastic deformation in the high-strength bolts. This phenomenon allowed energy dissipation and prevented severe buckling of the beam flanges and beam web.  相似文献   
953.
The availability of high strength steels and concrete leads to the use of thin steel plates in concrete-filled steel tubular beam-columns. However, the use of thin steel plates in composite beam-columns gives a rise to local buckling that would appreciably reduce the strength and ductility performance of the members. This paper studies the critical local and post-local buckling behavior of steel plates in concrete-filled thin-walled steel tubular beam-columns by using the finite element analysis method. Geometric and material nonlinear analyses are performed to investigate the critical local and post-local buckling strengths of steel plates under compression and in-plane bending. Initial geometric imperfections and residual stresses presented in steel plates, material yielding and strain hardening are taken into account in the nonlinear analysis. Based on the results obtained from the nonlinear finite element analyses, a set of design formulas are proposed for determining the critical local buckling and ultimate strengths of steel plates in concrete-filled steel tubular beam-columns. In addition, effective width formulas are developed for the ultimate strength design of clamped steel plates under non-uniform compression. The accuracy of the proposed design formulas is established by comparisons with available solutions. The proposed design formulas can be used directly in the design of composite beam-columns and adopted in the advanced analysis of concrete-filled thin-walled steel tubular beam-columns to account for local buckling effects.  相似文献   
954.
高功能结构用钢板的发展   总被引:5,自引:1,他引:5  
日本钢铁业近年来在建筑结构用钢的研发上,投注了相当多的人力资源,开发出一系列所谓的高功能结构用钢板,附予这些钢材各种不同的规格外性质保证,达到增加钢结构物安全性、造型美观、降低钢结构物建造成本等效益。由于地域关系,台湾的钢构及建筑业多少亦受到日本相关产业的影响,因此近年来业界对这类高功能结构用钢材的需求逐渐浮现,本文的主要内容,即在说明高功能结构用钢包括了高入热量焊接结构用钢、耐火钢、低降伏比钢、狭降伏强度变异钢、极低强度吸震钢板在日本的发展状况,以及中钢现有的研发成果,提供钢构及建筑业将来在选料用料上参考。  相似文献   
955.
华中地区钢铁企业植物配置探讨   总被引:6,自引:0,他引:6  
肖剑  胡志华  赵红 《中国园林》2004,20(11):50-53
钢铁企业为重污染企业,依据华中地区钢铁企业的立地条件提出了在华中地区钢铁企业环境建设中,植物品种的选择和植物配置的原则,得出在华中地区钢铁企业中植物配置的方法.并通过武汉钢铁(集团)公司和涟源钢铁(集团)公司中多年的实地栽培经验介绍适合华中地区钢铁企业的植物配置.  相似文献   
956.
One of the most common types of hybrid systems is represented by a hybrid coupled shear wall consisting of steel coupling beams and reinforced concrete shear walls, known as a hybrid wall system. This paper addressed the shear strength of connection between structural steel coupling beams and reinforced concrete shear walls. No specific guidelines are available for predicting the panel shear strength of steel coupling beam-wall connections in a hybrid coupled shear wall system. The panel shear strength of steel coupling beam-wall connections in a hybrid coupled shear wall system is examined through results of an experimental research programme where three 2/3-scale specimens were tested under cyclic loading. Panel shear strength reflects enhancement achieved through mobilization of the reinforced concrete panel using face bearing plates and/or horizontal ties in the panel region of steel coupling beam-wall connections. The results and discussion presented in this paper are compared with ASCE design guidelines for RCS composite joints, which form a similar structural system. Finally, this paper provides the background for design guidelines that include a design model to calculate the panel shear strength of steel coupling beam-wall connections.  相似文献   
957.
孙云  邓勇刚 《特种结构》2004,21(2):63-65
体外预应力加固方法是提高钢梁承载能力、改善其受力性能的一种简单易行的方法。本文对体外预应力加固简支实腹钢梁时体外预应力筋的线形布置、预应力损失以及内力增量的计算和体外预应力筋截面面积的确定进行了分析 ,并且对加固后钢梁的设计计算进行了研究 ,最后通过一实例进行了设计计算  相似文献   
958.
水柏铁路北盘江大桥主桥桥型为上承式钢管混凝土拱桥,跨度236m,施工所采用的单铰平面转体重量达104000kN。本文介绍该主桥的结构设计和采用的转体施工方法。  相似文献   
959.
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.  相似文献   
960.
Engineering decisions concerning the performance of existing structures must be made in the presence of uncertainties. The remaining capacity of corroded steel structures provides a good example of different aspects of uncertainty. These include: an unknown or partially known extent of damage; a variability in loading and an uncertain reserve of structural capacity depending on the mode of failure. The theory of structural reliability has been developed to provide a method of analysis for structural safety. In this paper, methods are proposed to compute the component reliability of corrosion-damaged steel members. The application of a recently developed theory called interval probability theory for system reliability is illustrated using the data obtained from actual samples of corroded beams.  相似文献   
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