scholarly journals The Influence of the Material Properties on the Ultimate Behaviour of Aluminium H-shaped Beams

2021 ◽  
Vol 15 (1) ◽  
pp. 176-188
Author(s):  
Rosario Montuori ◽  
Elide Nastri ◽  
Vincenzo Piluso ◽  
Alessandro Pisapia
Keyword(s):  
Material Properties ◽  
Slenderness Ratio ◽  
Bending Moment ◽  
Constitutive Law ◽  
Rotation Capacity ◽  
Moment Gradient ◽  
Dimensional Parameters ◽  
The Moment ◽  
Plastic Rotation Capacity ◽  
Ultimate Resistance

Background: In this paper, the influence of the Ramberg-Osgood exponent on the ultimate behaviour of the H-shaped (or I-shaped) aluminium beams subjected to non-uniform bending moment is investigated. Methods: In particular, the results of a wide parametric analysis recently carried out by the authors are herein exploited to point out the influence of the material properties. The flange slenderness, the flange-to-web slenderness ratio, and the non-dimensional shear length, accounting for the moment gradient, are the main non-dimensional parameters governing the ultimate resistance and the rotation capacity of H-shaped aluminium beams. Results: The influence of these parameters was investigated considering four different materials covering both low yielding-high hardening alloys and high yielding-low hardening alloys, which are characterised by significant differences in the values of the Ramberg-Osgood exponent of the stress-strain constitutive law of the material. Conclusion: Finally, empirical formulations for predicting the non-dimensional ultimate flexural strength and the plastic rotation capacity of H-section aluminium beams under moment gradient have been provided as a function of the Ramberg-Osgood exponent and all the above non-dimensional parameters.

Evaluation of Rotation Capacity of RHS Aluminium Alloy Beams by FEM Simulation: Temper T6

2016 ◽  
Vol 710 ◽  
pp. 281-287 ◽  
Author(s):  
Paolo Castaldo ◽  
Elide Nastri ◽  
Vincenzo Piluso
Keyword(s):  
Aluminium Alloy ◽  
Slenderness Ratio ◽  
Fem Simulation ◽  
Companion Paper ◽  
Constitutive Law ◽  
Geometrical Parameters ◽  
Rotation Capacity ◽  
Moment Gradient ◽  
The Moment ◽  
Material Constitutive Law

The aim of this work is the numerical assessment of the ultimate behaviour of aluminium alloy beams subjected to non-uniform bending. An extensive numerical analysis has been performed by means of FE code ABAQUS with reference to RHS sections considering different values of the main geometrical and mechanical parameters. In particular, regarding the geometrical parameters the flange slenderness, the flange-to-web slenderness ratio and the moment gradient parameter have been considered. In particular, their influence on the ultimate behaviour of such beams has been investigated by adopting the material constitutive law proposed by Eurocode 9 based on the Ramberg-Osgood model. The investigations concern these parameters considered separately as well as their interaction. The results are herein reported with reference to temper T6 and show the importance of the investigated parameters on the buckling strength and the rotational capacity of aluminium alloy beams. Temper T6 gives rise to a quite low hardening compared to temper T4, which is analysed in a companion paper.

Evaluation of Rotation Capacity of RHS Aluminium Alloy Beams by FEM Simulation: Temper T4

2016 ◽  
Vol 710 ◽  
pp. 288-294 ◽  
Author(s):  
Paolo Castaldo ◽  
Elide Nastri ◽  
Vincenzo Piluso
Keyword(s):  
Aluminium Alloy ◽  
Shape Factor ◽  
Fem Simulation ◽  
Constitutive Law ◽  
Buckling Strength ◽  
Rotation Capacity ◽  
Numerical Assessment ◽  
Moment Gradient ◽  
The Moment ◽  
Rotation Behaviour

The aim of this work consists in the numerical assessment of the moment-rotation behaviour of RHS aluminium alloy beams subjected to non-uniform bending through an extensive parametric analysis performed by means of FE code ABAQUS investigating the influence of the main geometrical and mechanical parameters. In particular, the influence of the flange slenderness, web stiffness and moment gradient are investigated by adopting the constitutive law proposed by Eurocode 9 based on the Ramberg-Osgood model whose shape factor characterise the hardening behaviour of the material. The investigations concern these factors considered separately as well as their interaction. The results are herein reported with reference to temper T4 and show the importance of some of the investigated parameters on both buckling strength and rotation capacity of aluminium alloy beams.

Evaluation of ductility and allowable moment redistribution in reinforced concrete structures

2000 ◽  
Vol 27 (6) ◽  
pp. 1286-1299 ◽  
Author(s):  
Adnan Shakir ◽  
David M Rogowsky
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beams ◽  
Bending Moment ◽  
Reinforced Concrete Beams ◽  
Bond Slip ◽  
Plastic Rotation ◽  
Moment Redistribution ◽  
Rotation Capacity ◽  
The Moment ◽  
Plastic Rotation Capacity

Designers can use moment redistribution to reduce the design bending moment envelope. Code provisions for moment redistribution are not entirely rational. They neglect the effects of important parameters on permissible moment redistribution and can be very conservative. To establish a realistic limit on permissible moment redistribution, one needs a rational model for predicting the plastic rotation capacity of critical sections (plastic hinges). This paper presents a model for computing the plastic rotation capacity, θp, and permissible moment redistribution, β, in reinforced concrete beams. Important parameters, affecting θp and β, are identified and incorporated in the model. The model is validated against experimental results and shows good agreement. A comparison of the moment redistribution limits is made between the model and CSA A23.3-94. Although the code provides a reasonable estimate of β for unfavourable combinations of parameters, the code can be very conservative when conditions are favourable for moment redistribution. Deeper beams with closely spaced stirrups allow significantly more moment redistribution than that predicted by the code.Key words: moment redistribution, ductility, plastic rotation capacity, bond-slip, shear cracking, reinforced concrete beams, c/d, ultimate concrete strain.

EFFECTS OF THE INITIAL DEFLECTION SHAPE ON THE MOMENT AMPLIFICATION FACTOR OF BEAM-COLUMNS

2018 ◽  
Vol 5 (2) ◽  
Author(s):  
Haruna Utsunomiya ◽  
Masayuki Haraguchi ◽  
Masae Kido ◽  
Keigo Tsuda
Keyword(s):  
Amplification Factor ◽  
Slenderness Ratio ◽  
Compressive Force ◽  
Bending Moment ◽  
Load Ratio ◽  
Longitudinal Direction ◽  
Initial Deflection ◽  
Axial Compressive Force ◽  
Beam Columns ◽  
The Moment

In the design of slender steel beam-columns, the moment amplification factor is used to estimate the maximum moment along with the longitudinal direction. While formulas for evaluating the factor have been presented on the basis of elastic or elastic-plastic analysis, the initial deflection of the column is not considered. The effect that the initial deflection on the strength and behavior of the column has been shown only when the initial deflection shape is half sine wave. This paper discusses the effect of the initial deflection shape on the value of the moment amplification factor by performing the analytical work. The analytical model is the hinged-end beam-column subjected to constant axial compressive force and end moments. First of all, the equilibrium differential equation which governs the problem is solved and the formula for calculating the bending moment is presented. In the parametric study, magnitude of initial deflection, initial deflection shape, axial load ratio, slenderness ratio and end moment ratio are selected as the parameters. In this paper, we discuss the effects of the amount of the initial deflection and the initial deflection shape.

MOMENT AMPLIFICATION FACTOR OF BEAM-COLUMNS WITH INITIAL DEFLECTION

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Haruna Utsunomiya ◽  
Masayuki Haraguchi ◽  
Masae Kido ◽  
Keigo Tsuda
Keyword(s):  
Amplification Factor ◽  
Slenderness Ratio ◽  
Compressive Force ◽  
Bending Moment ◽  
Load Ratio ◽  
Initial Deflection ◽  
Axial Compressive Force ◽  
Beam Columns ◽  
Moment Ratio ◽  
The Moment

In the design of slender steel beam-columns, the moment amplification factor is used to estimate the maximum bending moment. The formulas for evaluating the factor have been presented on the basis of the elastic or elastic-plastic analysis, however the initial deflection of beam-columns is not considered. This paper discusses the effect of initial deflection on the value of the moment amplification factor by performing the analytical work. The analytical model is a simply supported beam-column subjected to constant axial compressive force and end moments. First of all, the equilibrium differential equation which governs the problem is solved and the formula for calculating the bending moment is obtained. In the parametric study, magnitude of the initial deflection, the axial load ratio, the slenderness ratio and the end moment ratio are selected as the parameters. The effects of magnitude of the initial deflection and the end moment ratio on the moment amplification factor are discussed.

Ductility and linear analysis with moment redistribution in reinforced high-strength concrete beams

2005 ◽  
Vol 32 (1) ◽  
pp. 194-203 ◽  
Author(s):  
Ricardo N.F do Carmo ◽  
Sérgio M.R Lopes
Keyword(s):  
High Strength Concrete ◽  
Concrete Beams ◽  
High Strength ◽  
Linear Analysis ◽  
Strength Concrete ◽  
Plastic Rotation ◽  
Moment Redistribution ◽  
Rotation Capacity ◽  
The Moment ◽  
Plastic Rotation Capacity

The evaluation of the ductility of reinforced concrete beams is very important, since it is essential to avoid a fragile collapse of the structure by ensuring adequate deformation at the ultimate limit state. One of the procedures used to quantify ductility is based on deformations, namely, the plastic rotation capacity. Knowledge of the plastic rotation capacity of certain regions of the structure is important for a plastic analysis or a linear analysis with moment redistribution. An experimental program is described in this article. It is composed of 10 tests designed to study the moment redistribution and ductility of continuous high-strength concrete beams. Particular care was given to analysing how the tensile reinforcement ratio and the transverse reinforcement ratio influence the plastic rotation capacity of the beams. A comparative study was carried out on several codes related to the moment redistribution permitted and the experimental findings. It was found that some of the recommendations are unsafe. It was also found that high-strength concrete beams, when properly designed, have enough deformation capacity to be used in plastic analysis.Key words: structural concrete, plastic rotation, moment redistribution, high-strength concrete.

Experimental study of moment carrying behavior of typical Tibetan timber beam-column joints

2021 ◽  
pp. 136943322110015
Author(s):  
Ting Guo ◽  
Na Yang ◽  
Huichun Yan ◽  
Fan Bai
Keyword(s):  
Bending Moment ◽  
Structural Performance ◽  
Test Results ◽  
Timber Beam ◽  
Rotational Stiffness ◽  
Trilinear Model ◽  
Column Joint ◽  
Loading Tests ◽  
The Moment ◽  
Relationship Of

This study aimed to investigate the moment carrying behavior of typical Tibetan timber beam-column joints under monotonic vertical static load and also evaluate the influence of length ratio of Gongmu to beam (LRGB) and dowels layout on the structural performance of the joint. Six full-scale specimens were fabricated with same construction but different Gongmu length and dowels position. The moment carrying performance of beam-column joints in terms of failure mode, moment resistance, and rotational stiffness of joints were obtained via monotonic loading tests. Test results indicated that all joints are characterized by compressive failure perpendicular to grain of Ludou. Additionally, it was found that greater LRGB leads to greater initial rotational stiffness and maximum moment of the joint by an increase of restraint length for beam end; however, offsetting dowels toward column resulted smaller stiffness and ultimate bending moment of joints, particularly, offsetting Beam-Gongmu dowels toward column changed the moment-rotation curve pattern of the beam-column joint, accompanied by a hardening stiffness at last phase. Furthermore, a simplified trilinear model was proposed to represent the moment-rotation relationship of the typical Tibetan timber beam-column joint.

Ultimate resistance and rotation capacity of low yielding high hardening aluminium alloy beams under non-uniform bending

2019 ◽  
Vol 135 ◽  
pp. 123-136 ◽  
Author(s):  
Vincenzo Piluso ◽  
Alessandro Pisapia ◽  
Elide Nastri ◽  
Rosario Montuori
Keyword(s):  
Aluminium Alloy ◽  
Rotation Capacity ◽  
Ultimate Resistance

Experimental Evaluation of the Ultimate Bending Moment of a Slender Thin-Walled Box Girder

2015 ◽  
Vol 137 (2) ◽  
Author(s):  
José Manuel Gordo ◽  
C. Guedes Soares
Keyword(s):  
Residual Stresses ◽  
Progressive Collapse ◽  
Bending Moment ◽  
Bending Test ◽  
Postbuckling Behavior ◽  
Box Girder ◽  
Collapse Mode ◽  
Collapse Analysis ◽  
The Moment ◽  
Progressive Collapse Analysis

The results of a four points bending test on a box girder are presented. The experiment is part of series of tests with similar configuration but with different thickness and span between frames. The present work refers to the slenderest plate box girder with a plate's thickness of 2 mm but with a short span between frames. The experiment includes initial loading cycles allowing for partial relief of residual stresses. The moment curvature relationship is established for a large range of curvature. The ultimate bending moment (UM) of the box is evaluated and compared with the first yield moment and the plastic moment allowing the evaluation of the efficiency of the structure. The postbuckling behavior and collapse mode are characterized. Comparison of the experiment with a progressive collapse analysis method is made taking into consideration the effect of residual stresses on envelop of the moment curvature curve of the structure.

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