Load-carrying capacity of cold-formed beams subjected to overall lateral-torsional buckling and local plate buckling

Some particular and selected problems aimed at ultimate limit state and probability-based studies pertaining to lateral-torsional buckling of steel beams are described. Stochastic analysis of the ultimate limit state of a slender member IPE220 under bending was elaborated. The values of non-dimensional slenderness for which the statistical characteristics of random load-carrying capacity are maximal were determined. The stochastic computational model was created in the programme ANSYS. Geometric nonlinear solution was employed. In the conclusion of the article, the question of the random effect of the initial rotation of the cross-section on the load-carrying capacity is discussed.

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Inelastic Ultimate Load Analysis of Steel Frames Considering Lateral Torsional Buckling Under Distributed Loads

Periodica Polytechnica Civil Engineering ◽

10.3311/ppci.13513 ◽

2019 ◽

Author(s):

Mutlu Secer ◽

Ertugrul Turker Uzun

Keyword(s):

Carrying Capacity ◽

Ultimate Load ◽

Steel Frames ◽

Load Carrying Capacity ◽

Lateral Torsional Buckling ◽

Torsional Buckling ◽

Numerical Examples ◽

Buckling Behavior ◽

Load Carrying ◽

Load Analysis

Contemporary structural design approaches necessitates ways to determine realistic behavior of structures. For this purpose, inelastic ultimate load analysis methods are used widely since strength and stability of whole structure can be represented. In this study, a numerical method is proposed for determining inelastic ultimate load capacity of steel frames considering lateral torsional buckling behavior under distributed loads. In the analyses, inelastic material behavior, second-order effects and residual stresses of the structural frame system and its members are taken into account. Additionally, lateral torsional buckling behavior is considered in the analysis using finite difference method and it is used for determining the structural load carrying capacity of steel frames. Consequently, the problem associated with flexural capacity decreases due to lateral torsional buckling is precisely considered in the load increment steps of inelastic ultimate load analysis. In order to validate the proposed method, numerical examples from the literature are calculated considering the proposed method, AISC 360-16 design specification equations and approaches from the literature. Results of the numerical examples show that lateral torsional buckling is a key issue in determining structural load carrying capacity. Thus, proposed analysis method is shown to be an efﬁcient and consistent tool for inelastic ultimate load analysis.

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Experimental Research on Equivalent Rectangular Opening Castellated Beam with Fillet Corner

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.e7103.018520 ◽

2020 ◽

Vol 8 (5) ◽

pp. 5415-5420

Keyword(s):

Carrying Capacity ◽

Load Carrying Capacity ◽

Lateral Torsional Buckling ◽

Torsional Buckling ◽

Rectangular Section ◽

Flexure Mechanism ◽

Modes Of Failure ◽

Load Carrying ◽

Shear Buckling ◽

Castellated Beam

Nowadays the use of castellated beam has been admired due to its beneficial functions like a light in weight, easy to erect, economical and stronger. The castellated beam is manufactured from its parent solid I beam by cutting it in a zigzag pattern and again joining it by welding so that the depth of the beam increases. Hence, due to an increase in depth of beam load carrying capacity of the parent I section is increased with the same quantity of material and weight. The increase in depth of the castellated beam leads to web post-buckling and lateral-torsional buckling failure when these beams are subjected to loading. There are many other modes of failure like the formation of flexure mechanism, lateral-torsional buckling, and formation of Vierendeel mechanism, rupture of the welded joint in a web post and shear buckling of a web post which needs to be taken care of. Hence, in the present paper, an attempt has been made to evaluate existing literature, concerned with the strength of the beam by providing a rectangular opening and rectangular opening equivalent to diagonal & hexagonal opening with different angles of opening 300 , 450 & 600 . The fillet radius is provided to the corner of the rectangular opening as a result of a 54% increase in the load-carrying capacity of the rectangular section compared to the regular rectangular section.

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Experimental Investigation for Non and Partially Composite Cold-Formed Steel Floor Beams

Civil Engineering Journal ◽

10.28991/cej-2019-03091341 ◽

2019 ◽

Vol 5 (6) ◽

pp. 1407-1423

Author(s):

Tuka Mohammed Qasim ◽

Salah Rohaima Al-Zaidee

Keyword(s):

Carrying Capacity ◽

Single Channel ◽

Composite Model ◽

Load Carrying Capacity ◽

Lateral Torsional Buckling ◽

Torsional Buckling ◽

Buckling Modes ◽

The Third ◽

Load Carrying ◽

Cold Formed Steel

In this study, six full-scaled models of RC floors supported by cold-form steel sections have been tested. Each model consists of RC 75mm thick slab supported on two parallel cold-formed steel beams with a span of 3m and spacing of 500mm. The slab has an overhang part of 250mm on each side. In the first and fourth models, the slab has been casted directly on the top flanges with no shear connector to simulate the effectiveness of friction in resisting of the lateral-torsional buckling. Shear studs have been drilled in the second and fifth models to ensure the composite action. Finally, the flanges have been embedded for the third and sixth models. A single channel beam is used in the first, second, and third models while a built-up beam is used in the fourth, fifth, and sixth models. Each model has been loaded up to failure under a pure bending with two-line loads located at the third points. Data for loads, deformations, and strains have been gathered. Except the fourth and the sixth models that failed in local buckling modes, all other models failed in global lateral-torsional buckling modes. For the single beam models; the load carrying capacity of the non-composite model is 82.9% less than the capacity of the composite models with shear studs and embedded flange. For the built-up models; the load carrying capacity of the non-composite model is 44.2 % less than the loads of the composite model with shear stud and 48.7% less than the model with the embedded flange.

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Influence of Yield Strength Variability over Cross-Section to Steel Beam Load-Carrying Capacity

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2005.10.2.15129 ◽

2005 ◽

Vol 10 (2) ◽

pp. 151-160 ◽

Cited By ~ 3

Author(s):

J. Kala ◽

Z. Kala

Keyword(s):

Yield Strength ◽

Cross Section ◽

Carrying Capacity ◽

Bending Moment ◽

Statistical Characteristics ◽

Load Carrying Capacity ◽

Load Carrying ◽

Strength Variability ◽

Hot Rolled ◽

Hot Rolled Steel

Authors of article analysed influence of variability of yield strength over cross-section of hot rolled steel member to its load-carrying capacity. In calculation models, the yield strength is usually taken as constant. But yield strength of a steel hot-rolled beam is generally a random quantity. Not only the whole beam but also its parts have slightly different material characteristics. According to the results of more accurate measurements, the statistical characteristics of the material taken from various cross-section points (e.g. from a web and a flange) are, however, more or less different. This variation is described by one dimensional random field. The load-carrying capacity of the beam IPE300 under bending moment at its ends with the lateral buckling influence included is analysed, nondimensional slenderness according to EC3 is λ¯ = 0.6. For this relatively low slender beam the influence of the yield strength on the load-carrying capacity is large. Also the influence of all the other imperfections as accurately as possible, the load-carrying capacity was determined by geometrically and materially nonlinear solution of very accurate FEM model by the ANSYS programme.

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Fuzzy Sets Theory in Comparison with Stochastic Methods to Analyse Nonlinear Behaviour of a Steel Member under Compression

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2005.10.1.15135 ◽

2005 ◽

Vol 10 (1) ◽

pp. 65-75 ◽

Cited By ~ 5

Author(s):

Z. Kala

Keyword(s):

Fuzzy Sets ◽

Carrying Capacity ◽

Stochastic Methods ◽

Nonlinear Behaviour ◽

Load Carrying Capacity ◽

Load Carrying ◽

Input Parameters ◽

Stochastic Solution ◽

Fuzzy Solution ◽

Sets Theory

The load-carrying capacity of the member with imperfections under axial compression is analysed in the present paper. The study is divided into two parts: (i) in the first one, the input parameters are considered to be random numbers (with distribution of probability functions obtained from experimental results and/or tolerance standard), while (ii) in the other one, the input parameters are considered to be fuzzy numbers (with membership functions). The load-carrying capacity was calculated by geometrical nonlinear solution of a beam by means of the finite element method. In the case (ii), the membership function was determined by applying the fuzzy sets, whereas in the case (i), the distribution probability function of load-carrying capacity was determined. For (i) stochastic solution, the numerical simulation Monte Carlo method was applied, whereas for (ii) fuzzy solution, the method of the so-called α cuts was applied. The design load-carrying capacity was determined according to the EC3 and EN1990 standards. The results of the fuzzy, stochastic and deterministic analyses are compared in the concluding part of the paper.

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Pavement Damage Due to Conventional and New Generation of Wide-Base Super Single Tires

Tire Science and Technology ◽

10.2346/1.2174344 ◽

2005 ◽

Vol 33 (4) ◽

pp. 210-226 ◽

Cited By ~ 6

Author(s):

I. L. Al-Qadi ◽

M. A. Elseifi ◽

P. J. Yoo ◽

I. Janajreh

Keyword(s):

Carrying Capacity ◽

Material Properties ◽

Three Dimensional ◽

Fe Analysis ◽

Load Carrying Capacity ◽

Inflation Pressure ◽

3D Finite Element ◽

Load Carrying ◽

Pavement Damage ◽

New Generation

Abstract The objective of this study was to quantify pavement damage due to a conventional (385/65R22.5) and a new generation of wide-base (445/50R22.5) tires using three-dimensional (3D) finite element (FE) analysis. The investigated new generation of wide-base tires has wider treads and greater load-carrying capacity than the conventional wide-base tire. In addition, the contact patch is less sensitive to loading and is especially designed to operate at 690kPa inflation pressure at 121km/hr speed for full load of 151kN tandem axle. The developed FE models simulated the tread sizes and applicable contact pressure for each tread and utilized laboratory-measured pavement material properties. In addition, the models were calibrated and properly validated using field-measured stresses and strains. Comparison was established between the two wide-base tire types and the dual-tire assembly. Results indicated that the 445/50R22.5 wide-base tire would cause more fatigue damage, approximately the same rutting damage and less surface-initiated top-down cracking than the conventional dual-tire assembly. On the other hand, the conventional 385/65R22.5 wide-base tire, which was introduced more than two decades ago, caused the most damage.

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