scholarly journals The Assessment of the Slip Influence on the Deflection of the Steel Plate-Concrete Composite Beams

2016 ◽  
Vol 62 (2) ◽  
pp. 59-76 ◽  
Author(s):  
D. Kisała ◽  
K. Furtak

Abstract The aim of this paper is to present an assessment of the slip influence on the deflection of the steel plate-concrete composite beams, which are a new type of a design concept. The proposed method is based on the procedure included in the PN-EN 1992-1-1, which has been modified with taking into consideration interface slip. The theoretical analysis was verified by experimental studies.

2015 ◽  
Vol 19 (5) ◽  
pp. 525-543 ◽  
Author(s):  
Guang P Zou ◽  
Pei X Xia ◽  
Xin H Shen ◽  
Peng Wang

The interface slip will appear between the steel plates and concrete while the steel–concrete–steel composite beam under loading. It may influence the mechanical properties of the composite beam. In this paper, through theoretical analysis of the steel–concrete–steel composite beam, differential equation of interface slip is established at first. By simulating the real boundary, the formulas of interface slip are calculated under uniform and arbitrary concentrated load. Then, the axial force, the sectional curvature, and deformation of composite beams are obtained. In order to validate the reliability of the theoretical analysis, the deformation of 18 samples is calculated by using the deformation formulas of steel–concrete–steel composite beam. The results are in good agreement with the experimental consequences. Through an example, the mechanical properties of composite beams (axial force, sectional curvature, and deformation) are analyzed under interfacial slip. With the decreasing of interfacial slip, axial force of upper plate increases, and sectional curvature and deflection decrease. For lower steel plate, the interfacial slip has smaller effect.


2012 ◽  
Vol 594-597 ◽  
pp. 749-752
Author(s):  
Jian Jun Yu ◽  
Lian Guang Wang

Cold-formed U-shaped steel and concrete composite beam is a kind of composite beam which the steel and the concrete are integrated by welding connections on the cold-formed U-shaped steel and then pouring concrete on the steel. Now, many experts and scholars have carried out many experimental research and theoretical analysis about it. But, prestressed Cold-formed U-shaped steel and concrete composite beams have not been studied. Based on the structure , the nonlinear analysis mode of prestressed cold-formed U-shaped steel and concrete composite beams is proposed, the calculating program is researched. The calculating results show that the bearing capacity of composite beam increases with the increments of thickness of steel plate and concrete strength, and the thickness of steel plate has a larger effect than the width of the flange plate of concrete, applying prestress can enhance the bearing capacity and flexural rigidity of the composite beam.


2019 ◽  
Vol 23 (6) ◽  
pp. 1168-1178
Author(s):  
Wan Hong ◽  
Yuchen Jiang ◽  
Yong Fang ◽  
Xiamin Hu

Ductile shear connectors are often applied in timber-concrete composite beams. The relative interface slip of such kind of composite beams will affect the mechanical performance of the composite beams and result in structural nonlinearity. Gamma method which adopts effective bending stiffness to reflect semi-rigid connection is recommended in Eurocode 5. The effective bending stiffness is irrelevant to external loads and calculation points of the composite beam. However, actual bending stiffness distribution along the beam is variable due to that shear connectors are subjected to different shear force. In order to verify the accuracy of gamma method, four-point bending tests of a total of three glulam-concrete composite beams with lag screw connectors and one pure glulam beam were conducted in this article. The failure mode, bearing capacity, and load–deflection relationship were investigated in the experiment. Meanwhile, push-out tests of composite beams were also conducted for determination of the force–displacement relationship of ductile shear connectors. Then, numerical simulation using beam-truss model was established for investigation on the mechanism of composite beams. Finally, theoretical analysis of composite beams considering the effect of interface slip was also presented. Comparing results from gamma method with the presented method, it is shown that both methods can calculate deflection at serviceability limit state with high precision. However, non-uniform distribution of actual bending stiffness cannot be reflected by gamma method.


2010 ◽  
Vol 163-167 ◽  
pp. 846-853
Author(s):  
Xue Jun Zhou ◽  
Ting Zhang ◽  
Yuan Zhi Zhang

U-section steel-encased concrete composite beams is the new type composite beam.This kind of composite beam takes thick steel plate as bottom plate and thinner cold-formed thin-walled steel as web which are connected through a u-shaped section by welding, and then concrete are poured in the u-shaped. In this paper an experimental study was conducted on six full size simple supported U-section steel-encased concrete composite beams.The relationships of the load-deflection curves of the composite beams were obtained. From the experimental results,the variation laws of deflection are analysed,and three defletion formulas are analysed and compared. Based on actual code. A theoretical formula is proposed for defletion. The results of theoretical formula are proved to be in good agreement with the experimental results.


2021 ◽  
Vol 719 (2) ◽  
pp. 022036
Author(s):  
Song Yang ◽  
Fan Chen ◽  
Zubin Ai ◽  
Lingyuan Zhou ◽  
Zhensheng Cao

2020 ◽  
pp. 136943322098166
Author(s):  
Weiwei Lin

In this study, straight composite steel-concrete beams were tested to investigate their mechanical performance under combined negative bending and torsional moments. Two specimens were used in this study, and different ratios between the applied negative bending and torsional moments were induced. Load and deflection relationships, strain development on the steel main girder and shear connectors (stud), and the slip development on the steel-concrete interface were recorded in the test and reported in this paper. The results indicate that increase of torsional moment will result in the significant decrease of the load-carrying capacities (e.g. yield load and ultimate load) of the specimens. It was also found that the normal strains of stud shear connectors in such beams are very large and non-negligible compared to their shear strains. In addition, the maximum interface slip was found occurring at around the 1/4 span, and the support conditions and serious crack of the concrete were considered to be the main causes. The research results obtained in this study can provide references for the design and analysis of steel-concrete composite beams subjected to the combined negative bending and torsional moments.


Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 626
Author(s):  
Riccardo Scazzosi ◽  
Marco Giglio ◽  
Andrea Manes

In the case of protection of transportation systems, the optimization of the shield is of practical interest to reduce the weight of such components and thus increase the payload or reduce the fuel consumption. As far as metal shields are concerned, some investigations based on numerical simulations showed that a multi-layered configuration made of layers of different metals could be a promising solution to reduce the weight of the shield. However, only a few experimental studies on this subject are available. The aim of this study is therefore to discuss whether or not a monolithic shield can be substituted by a double-layered configuration manufactured from two different metals and if such a configuration can guarantee the same perforation resistance at a lower weight. In order to answer this question, the performance of a ballistic shield constituted of a layer of high-strength steel and a layer of an aluminum alloy impacted by an armor piercing projectile was investigated in experimental tests. Furthermore, an axisymmetric finite element model was developed. The effect of the strain rate hardening parameter C and the thermal softening parameter m of the Johnson–Cook constitutive model was investigated. The numerical model was used to understand the perforation process and the energy dissipation mechanism inside the target. It was found that if the high-strength steel plate is used as a front layer, the specific ballistic energy increases by 54% with respect to the monolithic high-strength steel plate. On the other hand, the specific ballistic energy decreases if the aluminum plate is used as the front layer.


2016 ◽  
Vol 19 (2) ◽  
pp. 231-258 ◽  
Author(s):  
Mahmood Heshmati ◽  
Bandar Astinchap ◽  
Masoud Heshmati ◽  
Mohammad Hosein Yas ◽  
Yasser Amini

In this paper, a set of numerical and experimental studies are performed to improve mechanical and vibrational properties of carbon nanotubes-reinforced composites. First, at a design concept level, linear distribution patterns of multi-walled carbon nanotubes through the thickness of a typical beam is adopted to investigate its fundamental natural frequency for a given weight percent of multi-walled carbon nanotubes. Both Timoshenko and Euler-Bernoulli beam theories are used in the derivation of the governing equations. The finite element method is employed to obtain a numerical approximation of the motion equation. Next, based on the introduced distribution patterns, laminated multi-walled carbon nanotubes-reinforced polystyrene-amine composite beams are fabricated. Static and experimental modal tests are performed to measure the effective stiffness and fundamental natural frequencies of the fabricated composite beams. Also, in order to generate realistic model to investigate the material properties of fabricated composite beams, the actual tensile specimens of multi-walled carbon nanotubes/polystyrene-amine composites are successfully fabricated and the tensile behaviors of both pure matrix and composites are investigated. To better interfacial bonding between carbon nanotubes and polymer, a chemical treatment is performed on carbon nanotubes. It is seen that the addition of a few wt. % of multi-walled carbon nanotubes make considerable increase in the Young's modulus and the tensile strength of the composite. It is observed from the free vibration tests that the uniform distribution of multi-walled carbon nanotubes results in an increase of 9.5% in the fundamental natural frequency of the polymer cantilever beam, whereas using the symmetric multi-walled carbon nanotube distribution increased its fundamental natural frequency by 17.32%.


Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 451
Author(s):  
Vladimir Balakshy ◽  
Maxim Kupreychik ◽  
Sergey Mantsevich ◽  
Vladimir Molchanov

This paper presents the results of theoretical and experimental studies of anisotropic acousto-optic interaction in a spatially periodical acoustic field created by a phased-array transducer with antiphase excitation of adjacent sections. In this case, contrary to the nonsectioned transducer, light diffraction is absent when the optical beam falls on the phased-array cell at the Bragg angle. However, the diffraction takes place at some other angles (called “optimal” here), which are situated on the opposite sides to the Bragg angle. Our calculations show that the diffraction efficiency can reach 100% at these optimal angles in spite of a noticeable acousto-optic phase mismatch. This kind of acousto-optic interaction possesses a number of interesting regularities which can be useful for designing acousto-optic devices of a new type. Our experiments were performed with a paratellurite (TeO2) cell in which a shear acoustic mode was excited at a 9∘ angle to the crystal plane (001). The piezoelectric transducer had to nine antiphase sections. The efficiency of electric to acoustic power conversion was 99% at the maximum frequency response, and the ultrasound excitation band extended from 70 to 160 MHz. The experiments have confirmed basic results of the theoretical analysis.


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