scholarly journals CHANGES IN VIBRATION CHARACTERISTICS OF STEEL BEAM-COLUMN CONNECTIONS WITH COMPOSITE BEAMS UNDER CYCLIC LOADING

2014 ◽  
Vol 79 (703) ◽  
pp. 1271-1278 ◽  
Author(s):  
Masahiro KURATA ◽  
Kaede MINEGISHI ◽  
Zhenyun TANG ◽  
Masayoshi NAKASHIMA
Keyword(s):  
Cyclic Loading ◽  
Composite Beams ◽  
Vibration Characteristics ◽  
Steel Beam

Finite Element Analysis of the Vibration Characteristics of Castellated Composite Beams

2014 ◽  
Vol 513-517 ◽  
pp. 91-94
Author(s):  
Bao Chu Yu ◽  
Guo Dong Wang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Dynamic Characteristics ◽  
Vibration Frequency ◽  
Composite Beam ◽  
Composite Beams ◽  
Vibration Characteristics ◽  
Steel Beam ◽  
Element Analysis ◽  
New Form

Steel-concrete castellated composite beams are a new form, also widely used in bridges and buildings. But the research for the vibration characteristics of the composite beams is less. In this paper, by using the principle of the finite element, it mainly analyzes the influence of some related elements, such as the steel beam web part of the opening location, the size, the location and so on, on composite beam vibration frequency to lay the foundation of further study on the dynamic characteristics of the castellated composite beam.

Vibration-based delamination evaluation in GFRP composite beams using ANN

2021 ◽  
pp. 096739112110033
Author(s):  
TG Sreekanth ◽  
M Senthilkumar ◽  
S Manikanta Reddy
Keyword(s):  
Finite Element ◽  
Natural Frequency ◽  
Composite Structures ◽  
Composite Beams ◽  
Vibration Characteristics ◽  
Mode Shapes ◽  
Aviation Industry ◽  
Frequency Data ◽  
Fiber Reinforced ◽  
Back Propagation Algorithm

Delamination is definitely an important topic in the area of composite structures as it progressively worsens the mechanical performance of fiber-reinforced polymer composite structures in its service period. The detection and severity analysis of delaminations in engineering areas like the aviation industry is vital for safety and economic considerations. The existence of delaminations varies the vibration characteristics such as natural frequencies, mode shapes, etc. of composites and hence this indication can be effectively used for locating and quantifying the delaminations. The changes in vibration characteristics are considered as inputs for the inverse problem to determine the location and size of delaminations. In this paper Artificial Neural Network (ANN) is used for delamination evaluationof glass fiber-reinforced composite beams using natural frequency as typical vibration parameter. The Finite Element Analysis is used for generating the required dataset for ANN. The frequency-based delamination prediction technique is validated by finite element models and experimental modal analysis. The results indicate that the ANN-based back propagation algorithm can predict the location and size of delaminations in composites with good accuracy for numerical natural frequency data but the accuracy is comparitivelyless for experimental natural frequency data.

Monotonic and fatigue assessment of steel-concrete composite beams strengthened with externally post-tensioned tendons

2018 ◽  
Author(s):  
◽  
Ayman Elzohairy
Keyword(s):  
Numerical Model ◽  
Composite Beam ◽  
Composite Beams ◽  
Fatigue Tests ◽  
Flexural Behavior ◽  
Bending Test ◽  
Steel Beam ◽  
Premature Failure ◽  
Post Tensioning ◽  
Post Tensioned

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The steel-concrete composite beam represents a structural system widely employed in both buildings and girder bridges. The coupling between steel beams and concrete flanges assures both economic and structural benefits because of quick construction of steel structures and large increase in stiffness due to the presence of concrete. Strengthening with external post-tensioning (PT) force is particularly effective and economical for long-span steel-concrete composite beams and has been employed with great success to increase the bending and shear resistance and correct excessive deflections. Applying external PT force to the steel-concrete composite beam is considered an active strengthening technique that can create permanent internal straining action in the beam which is opposite to the existing straining action due to the applied service loads. The most benefits of using this system of strengthening are an elastic performance to higher loads, higher ultimate capacity, and reduction in deformation under the applied loads. Under service loads, bridge superstructures are subjected to cyclic loads which may cause a premature failure due to fatigue. Therefore, fatigue testing is critical to evaluate existing design methods of steel-concrete composite beams. ... This research presents static and fatigue tests on four steel-concrete composite specimens to evaluate the effect of externally post-tensioned tendons on the ultimate strength and fatigue behavior of composite beams. Fatigue tests are conducted to a million cycles under a four-point bending test. In addition, final static tests are performed on fatigued specimens to evaluate the residual strength of the strengthened specimen. A numerical model is described to predict the fatigue response of the composite beam by considering the fatigue damage in the concrete flange. The accuracy of the developed numerical model is validated using the existing test data. The static test results indicate that the external post-tensioning force improves the flexural behavior of the strengthened specimen by increasing the beam capacity and reducing the tensile stress in the bottom flange of the steel beam. The fatigue results demonstrate that the external post-tensioning significantly decreases the strains in the shear connectors, concrete flange, and steel beam. The tendons demonstrated an excellent fatigue performance, with no indication of distress at the anchors.

scholarly journals INELASTIC BEHAVIOR OF STEEL BEAM TO COMPOSITE COLUMN CONNECTIONS : Test under Cyclic Loading

1981 ◽  
Vol 301 (0) ◽  
pp. 65-75
Author(s):  
MORIHISA FUJIMOTO ◽  
KOICHI ASAI ◽  
MAMORU KIMURA ◽  
KATSUHIKO SAITO
Keyword(s):  
Cyclic Loading ◽  
Steel Beam ◽  
Inelastic Behavior ◽  
Composite Column

Reliability analysis of shear connection in composite beams with profiled steel sheeting

2011 ◽  
Vol 8 (1) ◽  
pp. 29-34
Author(s):  
M. Youcef ◽  
M. Mimoune ◽  
F. Mimoune
Keyword(s):  
Reliability Analysis ◽  
Failure Modes ◽  
Composite Beams ◽  
Steel Beam ◽  
British Standard ◽  
Shear Connectors ◽  
Shear Connection ◽  
Composite Slabs ◽  
European Code ◽  
Headed Stud

This paper describes the reliability analysis of shear connection in composite beams with profiled steel sheeting. The profiled steel sheeting had transverse ribs perpendicular to the steel beam. The level of safety of shear connection, and failure modes were determinate. An extensive parametric study was conducted to study the effects on the safety and behaviour of shear connection by changing the profiled steel sheeting geometries, the diameter and height of headed stud, as well as the strength of concrete. We compared the level safety 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 overestimated the level safety of shear connection.

Experimental study on vertical vibration characteristics of medium-low speed maglev vehicle when standing still on steel beams

2021 ◽  
pp. 095440972110324
Author(s):  
Miao Li ◽  
Xiaohao Chen ◽  
Shihui Luo ◽  
Weihua Ma ◽  
Cheng Lei ◽  
...  
Keyword(s):  
Coupled System ◽  
Vertical Vibration ◽  
Vibration Characteristics ◽  
Steel Beams ◽  
Steel Beam ◽  
Air Spring ◽  
Low Speed ◽  
Maglev Vehicle ◽  
Excited Vibration ◽  
Eigen Frequencies

Levitation stability is the very basis for the dynamic operation of Electromagnetic Suspension (EMS) medium-low speed maglev trains (MSMT). However, self-excited vibration tends to occur when the vehicle is standing still above the lightweight lines, which remains a major constraint to the promotion of medium-low speed maglev technology. In order to study the vertical vibration characteristics of the coupled system of MSMT when it is standing still above lightweight lines, levitation tests were carried out on two types of steel beams: steel beam and active girder of the turnout, with a newly developed maglev vehicle using levitation frames with mid-set air spring. Firstly, modal tests were carried out on the steel beam to determine its natural vibration characteristics; secondly, the acceleration signals and the dynamic displacement signals of the air spring obtained at each measurement point were analyzed in detail in both the time and frequency domains, and the vertical ride comfort was assessed by means of the calculated Sperling index. Subsequently, theoretical explanations were given for the occurrence of self-excited vibration of coupled system from the perspective of the vehicle-to-guideway vibration energy input. Results show that the eigen frequencies of the vehicle on the steel beam and the turnout are 9.65 Hz and 2.15 Hz, respectively, the former being close to the natural frequency of the steel beam while the latter being close to the natural frequency of the air spring suspension system, thus causing the self-excited vibration of the coupled system. It is recommended to either avoid the main eigen frequencies of the coupled system or to increase the damping of the corresponding vibration modes to guarantee a reliable coupled system for its long-term performance. These results may provide valuable references for the optimal design of medium-low speed maglev systems.

Cyclic loading test for concrete-filled U-shaped steel beam–RC column connections

2012 ◽  
Vol 36 ◽  
pp. 325-336 ◽  
Author(s):  
Hong-Gun Park ◽  
Hyeon-Jong Hwang ◽  
Cheol-Ho Lee ◽  
Chang-Hee Park ◽  
Chang-Nam Lee
Keyword(s):  
Cyclic Loading ◽  
Steel Beam ◽  
Loading Test ◽  
Cyclic Loading Test ◽  
Rc Column

Behaviour of headed studs in composite beams: push-out tests

1988 ◽  
Vol 15 (2) ◽  
pp. 240-253 ◽  
Author(s):  
B. S. Jayas ◽  
M. U. Hosain
Keyword(s):  
Composite Beams ◽  
Shear Capacity ◽  
Concrete Slabs ◽  
Steel Beam ◽  
Principal Mode ◽  
Pull Out ◽  
Factor Design ◽  
Headed Stud ◽  
Load And Resistance Factor ◽  
Push Out

This paper briefly summarizes the results of tests conducted on 18 full-size push-out specimens and 4 pull-out specimens. The objective of the project was to study the behaviour of headed studs in composite beams with ribbed metal decks perpendicular and parallel to the steel beam. The longitudinal spacing of the headed studs and the rib geometry of the metal decks were the principal experimental parameters.Five of the push-out specimens had solid concrete slabs, in five specimens the ribbed metal deck was placed parallel to the steel beam, and in the remaining eight specimens the metal deck was perpendicular to the steel beam. In most cases 38 mm deck and 16 × 76 studs were used.Test results obtained by the authors appear to indicate that with some exceptions the current Canadian Standards Association and Load and Resistance Factor Design codes are able to predict stud strength correctly for specimens with solid slabs and with parallel ribbed slabs only when failure occurs owing to stud shearing, i.e., when the studs are spaced sufficiently apart. It is recommended that these codes include a provision to check the possibility of concrete-related failures when the longitudinal stud spacing approaches or falls below six times the stud diameter for solid and parallel ribbed slabs.Stud pull-out was the principal mode of failure in the specimens with perpendicular ribbed metal decks. An equation recently proposed by Hawkins and Mitchell appears to underestimate the capacity for specimens with 38 mm deck. For specimens with 76 mm deck, their equation overestimates the stud capacity. The authors have proposed two separate but similar empirical equations for specimens with 38 and 76 mm deck. Key words: composite beam, headed stud, stud shear capacity, stud pull-out failure, minimum stud spacing, perpendicular deck, parallel deck.

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