Abstract
This paper presents the experimental studies of the flexural behavior of steel-concrete composite
beams. Herein, steel-concrete composite beams were constructed with a welded steel I section beam and
concrete slab with different material strength. Four simply supported composite beams subjected to two-point
concentrated loads were tested and compared to investigate the effect of high strength engineering materials on the overall flexural response, including failure modes, load deflection behavior, strain response and interface slip. The experimental results show that the moment capacity of composite beams has been improved effectively when high-strength steel and concrete are used. Comparisons of the ultimate flexural strength of beams tested are then made with the calculated results according to the methods specified in guideline Eurocode 4. The ultimate flexural strength based on current codes may be slightly unconservative for predicating the moment capacity of composite beams with high-strength steel or concrete.
Key Words
composite beam; high-strength concrete, flexural behavior.
Address
School of Civil Engineering, Tianjin University, China
Department of Geotechnical Engineering, Tongji University, China
Abstract
In current European Standard EN 1993, the moment-rotation characteristics of beam-to-column joints made from steel with a yield stress > 460MPa are obtained from elastic design procedures. The strength of the joint basic components, such as the column web subject to local transverse compression, is thus limited to the yield resistance rather than the plastic resistance. With the recent developments of higher strength steel grades, the need for these restrictions should be revisited. However, as the strength of the steel is increased, the buckling characteristics become more significant and thus instability phenomena may govern the design. This paper summarizes a comprehensive set of finite element parametric studies pertaining to the strength behaviour of high-strength steel unstiffened I-columns in transverse compression. The paper outlines the implementation and validation of a three-dimensional finite element model and presents the relevant numerical test results. The finite element predictions are evaluated against the strength values anticipated by the EN 1993 for conventional steel columns and recommendations are made for revising the specifications.
Key Words
column web in compression; component method; connections; eurocode 3(en 1993); finite element method; high-strength steel; joints; strength.
Address
Department of Structural and Building Engineering – Steel and Timber Structures, Faculty of Civil Engineering and Geosciences, Delft University of Technology, PO Box 5048, 2600 GS Delft, The Netherlands
Institute of Computers and Systems Engineering of Coimbra (INESC-Coimbra), Rua Antero de Quental 199, 3000-033 Coimbra, Portugal
Abstract
Proper material constitutive models for concrete-filled tube (CFT) columns of circular cross section and subjected to pure bending moment are proposed. These material models are implemented into the Abaqus finite element program and verified against experimental data. It has been shown that the steel tube does not provide good confining effect to the concrete core when the CFT columns is subjected to pure
bending moment. When the diameter-to-thickness ratio of the CFT columns is small, the behavior of the CFT column is the same as the steel tube without a concrete core.
Key Words
concrete-filled tube; lateral confining pressure; finite element analysis.
Address
Department of Civil Engineering and Sustainable Environment Research Center,National Cheng Kung University, Tainan, Taiwan 701, R.O.C.
School of Architectural, Civil and Mechanical Engineering, Victoria University,Footscray Park Campus, Ballarat Road, Vic 8001, Australia
Abstract
The current research presents a detailed methodology for generating air blast loading for use within a finite element context. Parameters describing blast overpressure loading on a structure are drawn from open literature sources and incorporated within a blast load generation computer code developed for this research. This open literature approach lends transparency to the details of the blast load modeling, as compared with many commonly used approaches to blast load generation, for which the details are not publicly available. As a demonstration, the load generation code is used with the finite element software LS-DYNA to simulate the response of a steel plate and girder subjected to explosions modeled using these parameters as well as blast parameters from other sources.
Key Words
air blast; extreme loading; explosion; blast load modeling; nonlinear finite element analysis.
Address
School of Civil and Env. Eng., Cornell University, Ithaca, NY, USA
Abstract
In this study, specimens were made with profile thicknesses and shear reinforcement as parameters. The bending and shear behavior were checked, and comparative analysis was conducted of the results and the theoretical values in order to see the applicability of T-section Modular Composite Profiled Beams (TMPB). In TMPB, the profiles of formwork functions play a structural role resisting the load. Also, the module concept, which is introduced into TMPB, has advantages: it can be mass-produced in a factory, it is lighter than an existing H-beam, it can be fabricated on the spot, and its section size is freely adjustable. The T1 specimens exhibited ductile behavior, where the whole section displayed strain corresponding to yielding
strain at least without separation between modules. They also exhibited maximum strength similar to the theoretical values even if shear reinforcement was not applied, due to the marginal difference between shear strength and maximum bending monment of the concrete section. A slip between modules was incurred by shear failure of the bolts in all specimens, excluding the T1 specimen, and therefore bending moment could not be fully displayed.
Key Words
T-section; modular; composite; profiled; slip; shear reinforcement.
Address
Department of Architectural, Sahm-Yook University, Seoul, Korea
