Experimental Study on the Flexural Behavior of Concrete-Filled Steel Box Slabs

Different to conventional reinforced concrete or steel material, a new type of concrete-filled steel box slab has been proposed by effectively integrating the combined benefits of both steel and concrete. By filling concrete, this type of slab could avoid the local bucking of steel plate and then could provide a high moment capacity. Therefore, this study aims to investigate the flexural behavior of concrete-filled steel box slabs through testing seven specimens and characterize their failure characteristics, stress distribution and ultimate moment capacity. A comprehensive parametric study focuses on the influence of the steel plate thickness, the stud and stiffening plate on the slab flexural behavior. The results show that concrete-filled steel box slabs had a high moment capacity and good ductility. The thickness of the steel plate had a significant influence on the moment capacity of the specimen. The stud led to the reduction of the moment capacity of the slab. The stiffening plate effectively improved the flexural behavior of the specimen. Moreover, a calculation method was formulated to describe the moment capacity of the slab and compared with experimental results. The results show that the proposed method for the moment capacity of the slab was conservative and reasonable.

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Simplified calculation method for flexural moment capacity of cold-formed steel built-up section beams

Advances in Structural Engineering ◽

10.1177/1369433220931208 ◽

2020 ◽

Vol 23 (14) ◽

pp. 3153-3167

Author(s):

Xinmei Yao ◽

Xuhong Zhou ◽

Yu Shi ◽

Yu Guan ◽

Yuxuan Zou

Keyword(s):

Calculation Method ◽

Flexural Behavior ◽

Moment Capacity ◽

Failure Characteristics ◽

Box Section ◽

Cold Formed Steel ◽

The Moment ◽

Simplified Calculation ◽

The Web ◽

Simplified Calculation Method

Cold-formed steel built-up section beams are commonly employed in cold-formed steel framing owing to their excellent mechanical performance. In order to develop a simplified approach for obtaining the flexural moment capacity of built-up section beams, both experimental study and numerical analysis on the flexural behavior of cold-formed steel built-up I-section and box section beams under flexural load were carried out in this study. The I-section beams are assembled from two back-to-back cold-formed steel lipped channels, and the box section beams consist of a cold-formed steel plain channel overlapping a lipped channel. First, four-point bending tests were performed on 30 simply supported specimens having 10 different configurations, and the moment capacities and failure modes of built-up section beams at ultimate loads were investigated. The failure characteristics observed were the interaction of local and distortional buckling of the web and top flange for I-section beams and local buckling of the web and top flange in pure bending for box section beams. Then, finite element models were developed to simulate the tested specimens and validated against the experimental results in terms of the moment capacities and failure characteristics. Moreover, extensive parametric studies, including section height-to-width ratio and flange width-to-thickness ratio, were conducted with the validated numerical models to identify the key factors influencing built-up section beams. Finally, a simplified calculation method considering the reduction factor of the gross section modulus of the built-up section to predict the flexural moment capacities of cold-formed steel built-up I-section and box section beams was proposed.

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Flexural Behavior of Steel Beam Strengthening by Prestressing Strands

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.20.26421 ◽

2018 ◽

Vol 7 (4.20) ◽

pp. 572

Author(s):

Dr. Mohammed M. Rasheed ◽

Mr. Ali F. Atshan ◽

Mr. Kamal Sh. Mahmoud

Keyword(s):

Reference Beam ◽

Flexural Behavior ◽

Radius Of Curvature ◽

Steel Beams ◽

Steel Beam ◽

Bottom Flange ◽

Moment Capacity ◽

External Prestressing ◽

Prestressing Strands ◽

The Moment

Seven simply supported steel beams were tested to explain the effect of strengthening by external prestressing strands. All of the beams have the same steel section, clear span length and the strengthening samples which implemented by two external prestressing strands. The tested beams are divided into two categories according to existing of external prestressing strands, the first category consists of one steel beam as a reference, while, the second group deals with steel beams strengthening by external prestressing strands and consists of six steel beams divided according to the eccentricity location of prestressing strand with jacking stress (815 MPa). From experimental results, it was found that the moment curvature curves behavior for the tested beams are stiffer and with less ductility than the reference beams and the ultimate moment capacity is increased with increasing the eccentricity location. While, the maximum radius of curvature at bottom flange decreases with increasing the eccentricity location as compare with the reference beam.

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An Experimental and Numerical Study on the Flexural Performance of Over-Reinforced Concrete Beam Strengthening with Bolted-Compression Steel Plates: Part II

Applied Sciences ◽

10.3390/app10010094 ◽

2019 ◽

Vol 10 (1) ◽

pp. 94 ◽

Cited By ~ 1

Author(s):

Shatha Alasadi ◽

Zainah Ibrahim ◽

Payam Shafigh ◽

Ahad Javanmardi ◽

Karim Nouri

Keyword(s):

Failure Modes ◽

Steel Plate ◽

Numerical Study ◽

Load Capacity ◽

Plate Thickness ◽

Steel Plates ◽

Experimental Program ◽

Failure Characteristics ◽

Control Beam ◽

Concrete Failure

This study presents an experimental investigation and finite element modelling (FEM) of the behavior of over-reinforced simply-supported beams developed under compression with a bolt-compression steel plate (BCSP) system. This study aims to avoid brittle failure in the compression zone by improving the strength, strain, and energy absorption (EA) of the over-reinforced beam. The experimental program consists of a control beam (CB) and three BCSP beams. With a fixed steel plate length of 1100 mm, the thicknesses of the steel plates vary at the top section. The adopted plate thicknesses were 6 mm, 10 mm, and 15 mm, denoted as BCSP-6, BCSP-10, and BCSP-15, respectively. The bolt arrangement was used to implement the bonding behavior between the concrete and the steel plate when casting. These plates were tested under flexural-static loading (four-point bending). The load-deflection and EA of the beams were determined experimentally. It was observed that the load capacity of the BCSP beams was improved by an increase in plate thickness. The increase in load capacity ranged from 73.7% to 149% of the load capacity of the control beam. The EA was improved up to about 247.5% in comparison with the control beam. There was also an improvement in the crack patterns and failure modes. It was concluded that the developed system has a great effect on the parameters studied. Moreover, the prediction of the concrete failure characteristics by the FE models, using the ABAQUS software package, was comparable with the values determined via the experimental procedures. Hence, the FE models were proven to accurately predict the concrete failure characteristics.

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Experimental study on the flexural behavior of flat steel-concrete composite beam

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2019-0644 ◽

2020 ◽

Author(s):

Xianlei Cao ◽

Chao Cheng ◽

Min Wang ◽

Wen Zhong ◽

Zhengyi Kong ◽

...

Keyword(s):

Composite Beam ◽

Design Theory ◽

Shear Fracture ◽

Rapid Development ◽

Flexural Behavior ◽

Flexural Stiffness ◽

Moment Capacity ◽

New Type ◽

Flat Steel ◽

Ductility Capacity

In this study, a new type of composite beam named flat steel-concrete composite beam is suggested for the rapid development of assembly structure. The experiment of seven flat steel-concrete composite beams and one traditional steel-concrete composite beam are performed to investigate their flexural behaviors. The failure mode of bending-shear fracture for the flat steel-concrete composite beam is found while the traditional steel-concrete composite beam fails by compression-bending fracture. The plane cross-section assumption is applicable to the flat steel-concrete composite beam. Compared with the traditional steel-concrete composite beam, the flat steel-concrete composite beam exhibits higher flexural stiffness, higher moment capacity, and higher ductility capacity. Based on the design theory of the traditional steel-concrete composite beam, simplified models for estimating the flexural stiffness and ultimate moment capacity of the flat steel-concrete composite beam are proposed, and they agree well with test data.

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FLEXURAL BEHAVIOUR OF CONCRETE‐FILLED STEEL HOLLOW SECTIONS BEAMS

Journal of Civil Engineering and Management ◽

10.3846/1392-3730.2008.14.5 ◽

2008 ◽

Vol 14 (2) ◽

pp. 107-114 ◽

Cited By ~ 13

Author(s):

Arivalagan Soundararajan ◽

Kandasamy Shanmugasundaram

Keyword(s):

Fly Ash ◽

Beam Specimen ◽

Theoretical Studies ◽

Flexural Behaviour ◽

Moment Capacity ◽

Strength Concrete ◽

Ultimate Moment ◽

Low Strength ◽

The Moment ◽

Low Strength Concrete

This paper presents an experimental study of normal mix, fly ash, quarry waste and low strength concrete (brick‐bat lime concrete) contribution to the ultimate moment capacity of square steel hollow sections. Fifteen simply supported beam specimens of 1200‐mm long steel hollow sections filled with normal mix, fly ash, quarry waste and low‐strength concrete and identical dimensions of hollow sections were experimented. Extensive measurements of such material properties, strain and deflection were carried out. Theoretical studies of ultimate moment capacity of a beam specimen were also calculated in this study for comparison's sake. These experimental investigation results showed that normal mix, fly ash, quarry waste and low‐strength concrete enhance the moment carrying capacity of steel hollow sections. Furthermore, in these studies it can be found that normal mix, fly ash and quarry waste concrete can be used in composite construction to increase the flexural capacity of steel hollow sections. Santrauka Pateikiamas normalaus, lakiųjų pelenų, akmenų skaldymo atliekų ir mažo stiprumo (skaldytųjų plytų kalkinio) betonų įtakos kvadratinio skerspjūvio plieninių vamzdžių ribinei lenkiamajai galiai eksperimentinis tyrimas. Išbandyta penkiolika dviatramių sijų bandinių iš 1 200 mm ilgio plieninių tuščiavidurių profiliuočių, pripildytų normalaus, lakiųjų pelenų, akmenų skaldymo atliekų ir mažo stiprumo betonų ir identiškų matmenų tuščiavidurių profiliuočių. Atlikti didelės apimties medžiagų savybių, santykinių deformacijų ir įlinkių matavimai. Lyginant teoriškai apskaičiuota sijų laikomoji galia. Eksperimentinio tyrimo rezultatai parodė, kad normalus, lakiųjų pelenų, akmenų skaldymo atliekų ir mažo stiprumo betonai didina plieninių tuščiavidurių profiliuočių lenkiamąją galią. Be to, iš šio tyrimo galima matyti, kad normalus, lakiųjų pelenų ir akmenų skaldymo atliekų betonus galima naudoti kompozitinių konstrukcijų plieninių tuščiavidurių profiliuočių lenkiamajai galiai didinti.

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Flexural Behavior of Double-Skin Steel Tube Beams Filled with Fiber-Reinforced Cementitious Composite and Strengthened with CFRP Sheets

Materials ◽

10.3390/ma13143064 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3064

Author(s):

Ahmed Al-Nini ◽

Ehsan Nikbakht ◽

Agusril Syamsir ◽

Nasir Shafiq ◽

Bashar S. Mohammed ◽

...

Keyword(s):

High Performance ◽

Steel Tube ◽

Flexural Behavior ◽

Cementitious Composite ◽

Fiber Reinforced ◽

Moment Capacity ◽

Cfrp Sheets ◽

High Performance Fiber ◽

Double Skin ◽

The Moment

The concrete-filled double skin steel tube (CFDST) is a more viable option compared to a concrete-filled steel tube (CFST) due to consisting a hollow section, while degradation is enhanced simply by using carbon fiber-reinforced polymer (CFRP). Hence, the stabilization of a concrete’s ductile strength needs high- performance fiber-reinforced cementitious conmposite. This study investigates the behavior of high-performance fiber-reinforced cementitious composite-filled double-skin steel tube (HPCFDST) beams strengthened longitudinally with various layers, lengths, and configurtion of CFRP sheets. The findings showed that, with increased CFRP layers, the moment capacity and flexural stiffness values of the retrofitted HPCFDST beams have significantly improved. For an instant, the moment capacity of HPCFDST beams improved by approximately 28.5% and 32.6% when they were wrapped partially along 100% with two and three layers, respectively, compared to the control beam. Moreover, the moment capacity of the HPCFDST beam using two partial layers of CFRP along 75% of its sufficient length was closed to the findings of the beam with two full CFRP layers. For energy absorption, the results showed a vast disparity. Only the two layers with a 100% full length and partial wrapping showed increasing performance over the control. Furthermore, the typical failure mode of HPCFDST beams was observed to be local buckling at the top surface near the point of loading and CFRP rapture at the bottom of effect length.

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Experimental study on the flexural behavior of large-scale rectangular concrete-filled steel tubular beams

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952017000400007 ◽

2017 ◽

Vol 10 (4) ◽

pp. 895-905

Author(s):

J. M. Flor ◽

R. H. Fakury ◽

R. B. Caldas ◽

F. C. Rodrigues ◽

A. H. M. Araújo

Keyword(s):

Large Scale ◽

Flexural Behavior ◽

Test Results ◽

Rigid Plastic ◽

Moment Capacity ◽

Hollow Section ◽

And Performance ◽

The Moment ◽

Concrete Filling ◽

Rectangular Tubes

ABSTRACT This paper presents a series of test results of large-scale rectangular concrete-filled steel tubular (CFST) beams to explore their performance under pure bending. Concrete-filling tests were initially carried out on two beam specimens of 12-m in length to investigate the feasibility of casting horizontally large-scale rectangular tubes. A total of six 6-m long specimens were subjected to flexural test afterward, including four CFST beams and two steel hollow section (SHS) beams for comparison. The test results showed that the rectangular CFST beams behaved in a relatively ductile manner. The concrete infilling enhanced the flexural behavior and performance of the steel tubes. Finally, the rigid-plastic theory showed suitable to predict the moment capacity of CFST compact beams.

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Flexural Behavior of Steel Plate-Concrete Composite Beams

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.400-402.37 ◽

2008 ◽

Vol 400-402 ◽

pp. 37-42 ◽

Cited By ~ 3

Author(s):

Jian Guo Nie ◽

Jie Zhao

Keyword(s):

Composite Beam ◽

Steel Plate ◽

Concrete Strength ◽

Plate Thickness ◽

Reinforced Concrete Beams ◽

Flexural Behavior ◽

Connection Degree ◽

Three Point Bending ◽

Shear Connection ◽

Load Carrying

In this paper, the steel plate-concrete composite (SPCC) beam is developed, in which traditional steel beam in the steel-concrete composite beam is replaced by a steel plate. The aim to develop this type of composite beam is to provide a theoretical basis for design of SPCC structures and SPCC-strengthened structures. In order to investigate the flexural behavior of SPCC beams, tests were conducted on five specimens with loading cases of four-point or three-point bending. All the beams were identical in geometry, longitudinal reinforcement, stirrup, and concrete strength but various in steel plate thickness, shear connection degree, shear span length and cut-off position of steel plate. The structural behavior of the tested SPCC beams, including strain, deflection, crack width, load carrying capacity and deformability, etc., were measured and analyzed. Based on test results, it can be concluded that by means of appropriate shear connection degree and anchorage length, steel plate and concrete can work together very well and the SPCC beams have a very good ductility. The ultimate strength of the SPCC beams can be calculated by means of the same plastic method as reinforced concrete beams.

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Flexural Resistance of Steel-Coconut Shell Concrete-Steel Composite Beam with Normal and J-Hook Shear Studs

International Journal of Integrated Engineering ◽

10.30880/ijie.2020.12.09.025 ◽

2020 ◽

Vol 12 (9) ◽

Author(s):

Lakshmi Thangasamy ◽

◽

Gunasekaran Kandasamy ◽

Keyword(s):

Concrete Strength ◽

Steel Plates ◽

Coconut Shell ◽

Core Material ◽

River Sand ◽

Concrete Core ◽

Conventional Concrete ◽

Moment Capacity ◽

The Moment ◽

Core Concrete

Many researches on double skin sandwich having top and bottom steel plates and in between concrete core called as steel-concrete-steel (SCS) were carried out by them on this SCS type using with different materials. Yet, use of coconut shell concrete (CSC) as a core material on this SCS form construction and their results are very limited. Study investigated to use j-hook shear studs under flexure in the concept of steel-concrete-steel (SCS) in which the core concrete was CSC. To compare the results of CSC, the conventional concrete (CC) was also considered. To study the effect of quarry dust (QD) in its place of river sand (RS) was also taken. Hence four different mixes two without QD and two with QD both in CC and CSC was considered. The problem statement is to examine about partial and fully composite, moment capacity, deflection and ductility properties of CSC used SCS form of construction. Core concrete strength and the j-hook shear studs used are influences the moment carrying capacity of the SCS beams. Use of QD in its place of RS enhances the strength of concrete produced. Deflections predicted theoretically were compared with experimental results. The SCS beams showed good ductility behavior.

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