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Article
Publication date: 1 March 1996

Itaru Mutoh, Shiro Kato and Y. Chiba

Presents an alternative lower bound to the elastic buckling collapse of thin shells of revolution, in comparison with results from geometrically non‐linear elastic…

Abstract

Presents an alternative lower bound to the elastic buckling collapse of thin shells of revolution, in comparison with results from geometrically non‐linear elastic analysis. The numerical finite element method is based on axisymmetric rotational shell elements whose strain‐displacement relations are described by Koiter’s small finite deflection theory, with displacements expanded circumferentially using a Fourier series. First, compares the reduced stiffness linear analysis, based on the buckling equation without incremental linear in‐plane energy components corresponding to the lowest eigenmode (for a particular cylindrical shell under external pressure), with the results obtained by Batista and Croll. Second, the non‐linear astatic (quasi‐static) elastic analysis to clamped spherical caps under uniform external pressure is carried out in order to compare the results from a reduced stiffness analysis from viewpoints of not only buckling loads, but also total potential energy. Argues that the astatic buckling loads may relate to reductions due to a specific imperfection effect on elastic buckling collapses.

Details

Engineering Computations, vol. 13 no. 2/3/4
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 13 June 2016

Athanasios Bouboulas and Nikolaos Anifantis

– The purpose of this paper is to investigate the effect of crack surfaces contact on the post-buckling behavior of a slender column with a non-propagating crack.

Abstract

Purpose

The purpose of this paper is to investigate the effect of crack surfaces contact on the post-buckling behavior of a slender column with a non-propagating crack.

Design/methodology/approach

In this paper a 3D finite element model has been implemented to study the post-buckling behavior of a slender column with a non-propagating crack. According to this model, the column is discretized into three-dimensional solid elements. Contact conditions are considered between the crack surfaces. The non-linear equations for this model are solved using an incremental-iterative procedure, and the equilibrium path of the cracked column is extracted.

Findings

Load-displacement curves are presented for a cantilever column with a transverse surface crack of either uniform or non-uniform depth across the column cross-section. For both crack shapes, the load-displacement curves are presented for various values of crack depth and position. The results of this study are in good agreement with the results available in the literature. Comparisons with the results of the always-open crack were performed. The post-buckling behavior of a column with a uniform depth crack is more sensitive to variations in crack depth and position than the post-buckling behavior of a column with a non-uniform depth crack.

Originality/value

A 3D finite element approach for the post-buckling behavior of a transversely cracked column including contact between crack surfaces.

Details

International Journal of Structural Integrity, vol. 7 no. 3
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 23 September 2020

Fatimah De'nan, Nor Salwani Hashim and Lim Cheng Kuan

Tapered section can resist maximum stress at a single location while the stresses are considerably lower at the rest of the member; therefore, it could have higher…

Abstract

Purpose

Tapered section can resist maximum stress at a single location while the stresses are considerably lower at the rest of the member; therefore, it could have higher structural efficiency compared to conventional section. It could also satisfy functional requirements while reducing weight and cost in many fields of civil construction. Perforation in the steel section also eases the integration of Mechanical and Electrical (M&E) services such as ventilation pipes and electrical cables within the structural depths of the beam. In this analysis, the structural efficiency of tapered steel section with perforation under lateral-torsional buckling behaviour is investigated.

Design/methodology/approach

A total of 81 models are analysed using LUSAS software and five variables are investigated which involved perforation sizes, perforation shapes, perforation layout, tapering ratio and flange and Web thickness. Buckling moment is obtained from the analysis results in LUSAS software, while self-weight and structural efficiency are manually calculated.

Findings

Perforation size of 0.75 D has the highest structural efficiency, although it can withstand a smaller buckling load. This is due to its lower self-weight compared to other perforation sizes. The square perforation shape also has the highest structural efficiency compared to circular perforation and diamond perforation. An increment of percentage in structural efficiency of the square perforation shape with 0.75 D is the highest at 3.07%. The circular perforation shape with 0.75 D (Open-Open-Open perforation layout) has the highest increment of percentage in structural efficiency which is 2.37%. The tapering ratio of 0.3 is the most efficient and an increment of percentage in structural efficiency is 114.36%. The flange thickness of 0.02 m and Web thickness of 0.015 m has the highest structural efficiency at 45.756 and 29.171, respectively.

Originality/value

In conclusion, a section should be able to resist the large buckling moment and has a lower self-weight to achieve high structural efficiency.

Details

World Journal of Engineering, vol. 17 no. 6
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 6 December 2020

Fatimah De'nan, Nor Salwani Hashim and Zafira Nur Ezzati Mustafa

The purpose of this study is to know the buckling capacity for cold-formed C-column with perforation. Cold-formed C-column have been used in interior wall construction…

Abstract

Purpose

The purpose of this study is to know the buckling capacity for cold-formed C-column with perforation. Cold-formed C-column have been used in interior wall construction. The concept of web perforation in the column has been introduced to the construction sector to overcome the issue of material cost.

Design/methodology/approach

Initially, the determination of the suitable spacing for the space column for the affordable house is investigated. Analysis house frame has been done in STAAD Pro. (Staad Pro, 2003) software using cold-formed C-column without perforation. Perforation with circular shape has been used in this study with the size of 0.4, 0.6 and 0.8 D (D = 180 mm). Perforation spacing is 150, 250 and 350 mm are adopted.

Findings

For the specimen with 0.4 D perforation and the edge distance is 539 mm have the highest buckling capacity (26.59 kN). Reduction of buckling capacity is 5.31% from cold-formed C-column without perforation and reduction of the volume is −2.16%. For the same case with 0.8 D perforation, the buckling capacity reduces with 22.52% and volume is −6.85%.

Originality/value

The conclusion of this analysis, C-column without perforation have higher buckling capacity compare to C-column with perforations.

Details

World Journal of Engineering, vol. 18 no. 2
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 1 August 1998

Ron Postle and Jacqueline Rebecca Postle

The buckling behaviour of engineering materials has been researched extensively since the 1890s and more recently, thin shell theory has generalised the analysis to…

Abstract

The buckling behaviour of engineering materials has been researched extensively since the 1890s and more recently, thin shell theory has generalised the analysis to include complicated boundary conditions. However, the approximations and assumptions which form the basis of engineering models make them inappropriate for textile materials. Very small stresses on textile materials cause extremely large strains so that the deformations are highly nonlinear. In this paper, we develop a nonlinear mathematical method. In the final section, the nonlinear differential equations used are generalised into a nonlinear evolution equation which is completely integrable and thus solved analytically obtaining dynamical solution for three‐dimensional fabric drape. These analytical solutions are applicable under all conditions and are not subject to computational difficulties associated with finding numerical solutions for highly nonlinear problems. The use of this analytical approach to fabric mechanics and dynamics provides us with a very powerful tool to formulate and solve many long‐standing problems in fabric and clothing technology.

Details

International Journal of Clothing Science and Technology, vol. 10 no. 3/4
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 1 February 1992

M. Govindaraj, B. Chen and J. Koechling

Deals with the development of a control system for fabric pick‐and‐place operators based on the Clupicker device. Fabric mechanical properties are analysed for their…

Abstract

Deals with the development of a control system for fabric pick‐and‐place operators based on the Clupicker device. Fabric mechanical properties are analysed for their influence on the motions performed in picking up fabric pieces from a stack. The performance of the picking device on various woven fabrics has been studied. A stepping motor drive to the crank of the Clupicker enabled us to control the normal force applied by the picking wheel on the fabric stack. By controlling the normal force we could make the Clupicker perform well for fabrics with very different properties. A linear regression was found between the minimum normal force required for effective performance of the picker and bending rigidity of the fabric.

Details

International Journal of Clothing Science and Technology, vol. 4 no. 2/3
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 20 April 2012

David McEntire

The following article seeks to expand comprehension of the concept of vulnerability in order to promote further scholarship in this area and provide policy guidance for…

Abstract

Purpose

The following article seeks to expand comprehension of the concept of vulnerability in order to promote further scholarship in this area and provide policy guidance for practitioners.

Design/methodology/approach

Various findings from the academic literature pertaining to vulnerability are discussed in order to generate a more holistic understanding of this key factor of disaster.

Findings

This exposition defines vulnerability, illustrates the causes of vulnerability, identifies those who may be vulnerable to disasters, and suggests ways to reduce vulnerability.

Research limitations/implications

Because this paper offers a preliminary view that both includes and goes beyond the traditional social vulnerability school, additional research on this matter will undoubtedly be required. However, it is hoped that the breadth and complexity of challenges we are currently facing will be made manifest in this discussion.

Originality/value

This paper extends the author's prior work in this area and reinforces the need to give greater priority to the concept of vulnerability in disaster research and emergency management.

Details

Disaster Prevention and Management: An International Journal, vol. 21 no. 2
Type: Research Article
ISSN: 0965-3562

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Article
Publication date: 21 June 2011

David McEntire

This paper aims to expand comprehension of the concept of vulnerability in order to promote further scholarship in this area and provide policy guidance for practitioners.

Abstract

Purpose

This paper aims to expand comprehension of the concept of vulnerability in order to promote further scholarship in this area and provide policy guidance for practitioners.

Design/methodology/approach

Various findings from the academic literature pertaining to vulnerability are discussed in order to generate a more holistic understanding of this key factor of disaster.

Findings

This exposition defines vulnerability, illustrates the causes of vulnerability, identifies those who may be vulnerable to disasters, and suggests ways to reduce vulnerability.

Research limitations/implications

Because this paper offers a preliminary view that both includes and goes beyond the traditional social vulnerability school, additional research on this matter will undoubtedly be required. However, it is hoped that the breadth and complexity of challenges being faced currently will be made manifest in this discussion.

Originality/value

This paper extends the author's prior work in this area and reinforces the need to give greater priority to the concept of vulnerability in disaster research and emergency management.

Details

Disaster Prevention and Management: An International Journal, vol. 20 no. 3
Type: Research Article
ISSN: 0965-3562

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Article
Publication date: 1 June 1997

Jaroslav Mackerle

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…

Abstract

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

Details

Engineering Computations, vol. 14 no. 4
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 6 August 2018

Ebrahim Farajpourbonab, Hossein Showkati and Sunil Kute

The main function of the castellation process is making I-sections stiffer by increasing the height of web and supplying a higher moment capacity of primary axis than…

Abstract

Purpose

The main function of the castellation process is making I-sections stiffer by increasing the height of web and supplying a higher moment capacity of primary axis than plain-webbed members of the same weight. In addition, it optimizes the use of heavy, costly constructional steel material and provides good services accessibility. The purpose of this study was to investigate the strength and buckling behavior of axially loaded castellated cruciform steel columns using finite element analysis. Although a significant body of research exists on the failure of different columns, there is no proper criterion introduced to determine the point of buckling in the equilibrium path of an imperfect column.

Design/methodology/approach

This paper considers a wide range of practical geometric dimensions and various end conditions using ANSYS software. Findings are reported for about 224 samples of castellated cruciform I-shaped sections, and a simplified approach to evaluate buckling capacity of castellated columns, using the slenderness-load curve, is developed. In addition, the axial compressive capacities of those steel sections are investigated numerically in the current study.

Findings

The results of nonlinear analyses of these columns revealed that the load-carrying capacity of castellated cruciform steel columns far outweighs and is more appropriate than that of the traditional cruciform steel columns. In the present paper, new geometric criteria have been introduced having the ability to cover different types of columns. It shows the critical load of columns in the range of elastic and inelastic behavior.

Practical implications

This study can provide a background for practical engineering applications and design specifications for steel structures with castellated sections. In the present paper, new geometric criteria have been introduced having the ability to cover different types of columns. It shows the critical load of columns showing both elastic and inelastic behavior. Because this method showed reliable performance, it can be used during experimental tests for detecting buckling point.

Originality/value

This study can provide background for practical engineering applications and design specifications for steel structures with castellated sections; also, a physical criterion has been defined for calculating the buckling load of real columns.

Details

World Journal of Engineering, vol. 15 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

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