Bending performance analysis of precast composite beams with precast ECC plate

A timber–lightweight−concrete (TLC) composite beam connected with a ductile connector in which the ductile connector is made of a stainless−steel bolt anchored with nuts at both ends was proposed. The push−out results and bending performance of the TLC composite specimens were investigated by experimental testing. The push−out results of the shear specimens show that shear–slip curves exhibit good ductility and that their failure can be attributed to bolt buckling accompanied by lightweight concrete cracking. Through the bending tests of ten TLC composite beams and two contrast (pure timber) beams, the effects of different bolt diameters on the strengthening effect of the TLC composite beams were studied. The results show that the TLC composite beams and contrast timber beams break on the timber fiber at the lowest edge of the TLC composite beam, and the failure mode is attributed to bending failure, whereas the bolt connectors and lightweight concrete have no obvious breakage; moreover, the ductile bolt connectors show a good connection performance until the TLC composite beams fail. The ultimate bearing capacities of the TLC composite beams increase 2.03–3.5 times compared to those of the contrast beams, while the mid-span maximum deformation decrease nearly doubled.

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Flexural Behavior of Fiber-Reinforced Self-Stressing Concrete T-Shaped Composite Beams

Advances in Civil Engineering ◽

10.1155/2020/8810440 ◽

2020 ◽

Vol 2020 ◽

pp. 1-17 ◽

Cited By ~ 1

Author(s):

Boxin Wang ◽

Ruichang Fang ◽

Qing Wang

Keyword(s):

Composite Beam ◽

Mechanical Analysis ◽

Composite Beams ◽

Experimental Results ◽

Flexural Behavior ◽

Fiber Reinforced ◽

Beam Test ◽

Test Beam ◽

Bending Performance ◽

Laminated Layer

Given the excellent crack resistance performance of steel fiber-reinforced self-stressing concrete (SFRSSC), the bending performance of some composite beams with SFRSSC laminated layers was studied. The experiment conducted in this study comprised a single-span composite beam test (including 3 test beams) and a two-span continuous composite beam test (including 2 test beams). All the test beams were T-shaped. The cracking load, yielding load, and ultimate load of all the test beams were recorded and comparatively analyzed. Experimental results showed that the cracking load of the test beam with an SFRSSC laminated layer is significantly increased. Mechanical analysis and numerical simulation of the test beams were conducted, and the obtained results agreed well with the experimental results. The composite beams under different working conditions were also numerically simulated. Through the simulation, reasonable ranges of precompressive stress and length of the SFRSSC laminated layer at intermediate support of continuous composite beam were obtained.

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Nonlinear Analysis on Flexural Behavior of Externally Prestressed Composite Beam

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.1596 ◽

2011 ◽

Vol 71-78 ◽

pp. 1596-1600

Author(s):

Yun Long Zhang

Keyword(s):

Composite Beam ◽

Constitutive Relations ◽

Composite Beams ◽

Flexural Behavior ◽

Nonlinear Material ◽

Bending Performance ◽

Bending Process ◽

Steel Bars ◽

Anchor Points ◽

Nonlinear Constitutive Relations

Steps loading method was used to caculate the whole bending process of a composite beam loaded verticaly in order to accurately analyze the bending performance of composite beams. It has taken into account a variety nonlinear constitutive relations of different materials and based on the layered-step sections transformed method. The displacement of external prestressed steel bars were expressed with rotation angles at anchor points using finite bar elements method. This method is proved reasonable and reliable by comparative analysis of the calculating and the experimental results. It is feasible to analyze the forces and deformations of composite beams which were effcted by nonlinear material factors with layered-step sections transformed method.

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Numerical Analysis on the Bending Performance of Prestressed Superposing-Poured Composite Beams

Advances in Civil Engineering ◽

10.1155/2020/8897621 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Jianmin Wang ◽

Chengfeng Zhu ◽

Ziqiang Xiao ◽

Qijun Zhao ◽

Junzhe Liu

Keyword(s):

Lightweight Aggregate ◽

Composite Beams ◽

Normal Weight ◽

Lightweight Aggregate Concrete ◽

Bending Performance ◽

Interval Time ◽

Normal Weight Concrete ◽

Prestressing Force ◽

Bonding Performance ◽

Interlayer Slip

Aiming at the bending performance of the prestressed superposing-poured concrete beam, the numerical simulation on the composite beams poured with the normal weight concrete (NWC) superposed on the fibred ceramsite lightweight aggregate concrete (LWAC) was conducted. Three kinds of prestressing schemes, straight linear prestressing force, curved prestressing force not across the casting interface, and curved prestressing force across the casting interface, were simulated for comparison, and the influence of the casting interval time was also considered. Results indicate that the stiffness of the superposing-poured beam can be effectively strengthened by considered schemes of the prestressing force; in addition, there are certain increases on the ultimate load except imposing the straight linear prestressing force. As the curved prestressing force is imposed across the casting interface, the maximal interlayer slip of the casting interfacial transition zone (C-ITZ) approximately equals to that without the prestressing force. The scalar stiffness degradation (SDEG) of the C-ITZ for the casting interval time being 14 days is obvious because of the weakening on the bonding performance of the C-ITZ. Comparatively, the SDEG variation of the C-ITZ in the model with the curved prestressing force across the casting interface is smoother and smaller on the whole than the other two prestressed schemes for the case of the casting interval time being 14 days.

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Improving four-point bending performance of marine composite sandwich beams by core modification

Journal of Composite Materials ◽

10.1177/0021998319874502 ◽

2020 ◽

Vol 54 (8) ◽

pp. 1049-1066

Author(s):

F Balıkoğlu ◽

N Arslan ◽

TK Demircioğlu ◽

O İnal ◽

M İren ◽

...

Keyword(s):

Bending Strength ◽

Mechanical Performance ◽

Composite Beams ◽

Bending Stiffness ◽

Bending Test ◽

Sandwich Composite ◽

Foam Core ◽

Sandwich Beams ◽

Bending Performance ◽

Four Point Bending

The aim of this study was to improve four-point bending performance of foam core sandwich composite beams by applying various core machining configurations. Sandwich composites have been manufactured using perforated and grooved foam cores by vacuum-assisted resin transfer moulding method with vinyl-ester resin system. The influence of grooves and perforations on the mechanical performance of marine sandwich composite beams was investigated under four-point bending test considering the weight gain. Bending strength and effective bending stiffness increased up to 34% and 61%, respectively, in comparison to a control beam without core modification. Analytical equations were utilised for calculating the mid-span deflection, equivalent bending stiffness and ultimate bending strength of the sandwich beams. Finite element analysis was also performed to analyse the flexural response of the specimens taking into account the combined effect of orthotropic linear elasticity of the face sheet and the non-linear behaviour of the foam core.

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