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Article
Publication date: 30 November 2021

Supen Kumar Sah and Anup Ghosh

The purpose of this article is to carry out the thermal buckling analysis of power and sigmoid functionally graded material Sandwich plate (P-FGM and S-FGM) under uniform, linear…

Abstract

Purpose

The purpose of this article is to carry out the thermal buckling analysis of power and sigmoid functionally graded material Sandwich plate (P-FGM and S-FGM) under uniform, linear, nonlinear and sinusoidal temperature rise.

Design/methodology/approach

Thermal buckling of FGM Sandwich plates namely, FGM face with ceramic core (Type-A) and homogeneous face layers with FGM core (Type-B), incorporated with nonpolynomial shear deformation theories are considered for an analytical solution in this investigation. Effective material properties and thermal expansion coefficients of FGM Sandwich plates are evaluated based on Voigt's micromechanical model considering power and sigmoid law. The governing equilibrium and stability equations for the thermal buckling analysis are derived based on sinusoidal shear deformation theory (SSDT) and inverse trigonometric shear deformation theory (ITSDT) along with Von Karman nonlinearity. Analytical solutions for thermal buckling are carried out using the principle of minimum potential energy and Navier's solution technique.

Findings

Critical buckling temperature of P-FGM and S-FGM Sandwich plates Type-A and B under uniform, linear, non-linear, and sinusoidal temperature rise are obtained and analyzed based on SSDT and ITSDT. Influence of power law, sigmoid law, span to thickness ratio, aspect ratio, volume fraction index, different types of thermal loadings and Sandwich plate types over critical buckling temperature are investigated. An analytical method of solution for thermal buckling of power and sigmoid FGM Sandwich plates with efficient shear deformation theories has been successfully analyzed and validated.

Originality/value

The temperature distribution across FGM plate under a high thermal environment may be uniform, linear, nonlinear, etc. In practice, temperature variation is an unpredictable phenomenon; therefore, it is essential to have a temperature distribution model which can address a sinusoidal temperature variation too. In the present work, a new sinusoidal temperature rise is proposed to describe the effect of sinusoidal temperature variation over critical buckling temperature for P-FGM and S-FGM Sandwich plates. For the first time, the FGM Sandwich plate is modeled using the sigmoid function to investigate the thermal buckling behavior under the uniform, linear, nonlinear and sinusoidal temperature rise. Nonpolynomial shear deformation theories are utilized to obtain the equilibrium and stability equations for thermal buckling analysis of P-FGM and S-FGM Sandwich plates.

Article
Publication date: 2 October 2009

B. Namiranian, S. Shaikhzadeh Najar and A. Salehzadeh Nobari

The purpose of this paper is to evaluate some important parameters in plate buckling of fused interlining worsted fabric with different weight and laying‐up direction. The article…

Abstract

Purpose

The purpose of this paper is to evaluate some important parameters in plate buckling of fused interlining worsted fabric with different weight and laying‐up direction. The article compares the formability of fused fabric composite by two different methods (Lindberg's hypothesis and fabric assurance by simple testing method).

Design/methodology/approach

Plate buckling compression behavior of fused fabric composite is investigated using a special designed clamp according to Dahlberg's test method.

Findings

The result shows that fusible interlining lay‐up angle significantly influences on buckling parameters. It is indicated that the buckling behavior of fused fabric composite against lay‐up interlining direction is in accordance with interlining buckling behavior. The result of research suggests that the formability behavior of fused fabric composite with interlining lay‐up direction is predictable according to Lindberg's method.

Research limitations/implications

Experimental design is limited at low speed. Further research works are needed to perform buckling behavior of fused fabric composites at higher speeds as well as under cyclic loading conditions.

Originality/value

Compression plate buckling behavior of fused interlining fabrics is predictable against interlining laying‐up direction. The result of this research could be used in the area of garment quality serviceability.

Details

International Journal of Clothing Science and Technology, vol. 21 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 4 February 2020

Yanni Bouras and Zora Vrcelj

Concrete arch structures are commonly constructed for various civil engineering applications. Despite their frequent use, there is a lack of research on the response and…

Abstract

Purpose

Concrete arch structures are commonly constructed for various civil engineering applications. Despite their frequent use, there is a lack of research on the response and performance of concrete arches when subjected to fire loading. Hence, this paper aims to investigate the response and in-plane failure modes of shallow circular concrete arches subjected to mechanical and fire loading.

Design/methodology/approach

This study is conducted through the development of a three-dimensional finite element (FE) model in ANSYS. The FE model is verified by comparison to a non-discretisation numerical model derived herein and the reduced modulus buckling theory, both used for the non-linear inelastic analysis of shallow concrete arches subjected to uniformly distributed radial loading and uniform temperature field. Both anti-symmetric and symmetric buckling modes are examined, with analysis of the former requiring geometric imperfection obtained by an eigenvalue buckling analysis.

Findings

The FE results show that anti-symmetric bifurcation buckling is the dominant failure mode in shallow concrete arches under mechanical and fire loading. Additionally, parametric studies are presented which illustrate the influence of various parameters on fire resistance time.

Originality/value

Fire response of concrete arches has not been reported in the open literature. The authors have previously investigated the stability of shallow concrete arches subjected to mechanical and uniform thermal loading. It was found that temperature greatly reduced the buckling loads of concrete arches. However, this study was limited to the simplifying assumptions made which include elastic material behaviour and uniform temperature loading. The present study provides a realistic insight into the fire response and stability of shallow concrete arches. The findings herein may be adopted in the fire design of shallow concrete arches.

Details

Journal of Structural Fire Engineering, vol. 11 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

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 plain-webbed…

102

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

Article
Publication date: 4 January 2016

Pankaj V Katariya and Subrata Kumar Panda

The purpose of this paper is to develop a general mathematical model for laminated curved structure of different geometries using higher-order shear deformation theory to evaluate…

Abstract

Purpose

The purpose of this paper is to develop a general mathematical model for laminated curved structure of different geometries using higher-order shear deformation theory to evaluate in-plane and out of plane shear stress and strains correctly. Subsequently, the model has to be validated by comparing the responses with developed simulation model (ANSYS) as well as available published literature. It is also proposed to analyse thermal buckling load parameter of laminated structures using Green–Lagrange type non-linear strains for excess thermal distortion under uniform temperature loading.

Design/methodology/approach

Laminated structures known for their flexibility as compared to conventional material and the deformation behaviour are greatly affected due to combined thermal/aerodynamic environment. The vibration/buckling behaviour of shell structures are very different than that of the plate structures due to their curvature effect. To model the exact behaviour of laminated structures mathematically, a general mathematical model is developed for laminated shell geometries. The responses are evaluated numerically using a finite element model-based computer code developed in MATLAB environment. Subsequently, a simulation model has been developed in ANSYS using ANSYS parametric design language code to evaluate the responses.

Findings

Vibration and thermal buckling responses of laminated composite curved panels have been obtained based on proposed model through a customised computer code in MATLAB environment and ANSYS simulation model using ANSYS parametric design language code. The convergence behaviour are tested and compared with those available in published literature and ANSYS results. Finally, the investigation has been extended to examine the effect of different parameters (thickness ratios, curvature ratios, modular ratios, number of layers and support conditions) on the free vibration and thermal buckling responses of laminated curved structures.

Practical implications

The present paper intends to give sufficient amount of numerical experimentation, which may lead to help in designing of finished product made up of laminated composites. Most of the aerospace, space research and defence organisation intend to develop low cost and high durable products for real hazard conditions by taking combined loading and environmental conditions. Further, case studies might lead to a lighter design of the laminated composite panels used in high-performance systems, where the weight reduction is the major parameter, such as aerospace, space craft and missile structures.

Originality/value

In this analysis, the geometrical distortion due to temperature is being introduced through Green–Lagrange sense in the framework of higher-order shear deformation theory for different types of laminated shells (cylindrical/spherical/hyperboloid/elliptical). A simulation-based model is developed using ANSYS parametric design language in ANSYS environment for different geometries and loading condition and compared with the numerical model.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 88 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 11 January 2023

Nor Salwani Hashim and Fatimah De’nan

It is generally known that the perforated section such as the castellated section is good to sustain distributed loads but inadequate to sustain highly concentrated loads…

Abstract

Purpose

It is generally known that the perforated section such as the castellated section is good to sustain distributed loads but inadequate to sustain highly concentrated loads. Therefore, it is possible to design the opening in a different arrangement of web opening to achieve section efficiency, thus improving the strength and torsional behaviour of the section with web opening. This study aims to focus on the finite element analysis of I-beam with and without openings in steel section dominated to lateral-torsional buckling behaviour.

Design/methodology/approach

In this work, the analysis of different sizes, shapes and arrangements of web opening is performed by using LUSAS application to conduct numerical analysis on lateral-torsional buckling behaviour. This involves three diameter sizes of web opening, five types of opening shapes and two criteria of the model.

Findings

The section with c-hexagon web opening was placed about 200-mm centre to centre and 100-mm edge distance, contribute to 7.26% increase of buckling capacity. For the section with 150-mm centre to centre and 50-mm edge distance, the occurrence of local buckling contributes to decrease of lateral buckling section capacity to 19.943 kNm, where pure lateral-torsional buckling mostly occurred because of prevented section. Besides that, the web opening diameter was also analysed. The web crippling was observed because of the increase of opening diameter from 0.67 to 0.80 D.

Originality/value

This contributes to a decrease in buckling capacity as figured in the contour of the deformed shape. For Model 1, an increase of buckling capacity (31.46%) is observed when the opening diameter are changed from 0.67 to 0.80 D.

Details

World Journal of Engineering, vol. 21 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 4 October 2011

Jurgita Domskienė, Eugenija Strazdienė and Paule Bekampienė

The purpose of this paper is to optimise parameters of digital image analysis to investigate the deformation behaviour of woven sample and to detect the onset and variation of…

Abstract

Purpose

The purpose of this paper is to optimise parameters of digital image analysis to investigate the deformation behaviour of woven sample and to detect the onset and variation of wrinkling that occurs due to bias‐tensioned fabric buckling.

Design/methodology/approach

Using models of predescribed shape, the relationship between the digitized gray scale intensities and wrinkles of the surface are analysed and conditions of specimen illumination and filtering procedures are chosen.

Findings

It is proposed to convert acquired images to binary to record the onset of buckling and to estimate critical buckling parameters of stretched woven samples. The threshold value is determined as mean value of approximated histogram of stretched specimen centre line. It is defined that profile curve and gray scale disperse presented by parameter CV can be used to obtain additional information and to compare behaviour of different samples during bias tension.

Research limitations/implications

Proposed image analysis technique allows detection of the onset of buckling wave formation and evaluation of surface waviness changes in woven samples different in colour and weave type tension. However, the behaviour of fabric samples with sharp multicoloured and complicated patterns cannot be assessed by gray scale imaging.

Originality/value

The proposed approach can be adjusted to investigate different wrinkling problems – buckling during simple shearing or picture frame test, seam puckering, draping.

Details

International Journal of Clothing Science and Technology, vol. 23 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 2 August 2018

Mohammad Malikan

Thermal buckling of double-layered piezoelectric nanoplates has been analyzed by applying an external electric voltage on the nanoplates. The paper aims to discuss this issue.

93

Abstract

Purpose

Thermal buckling of double-layered piezoelectric nanoplates has been analyzed by applying an external electric voltage on the nanoplates. The paper aims to discuss this issue.

Design/methodology/approach

Double-layered nanoplates are connected to each other by considering linear van der Waals forces. Nanoplates are placed on a polymer matrix. A comprehensive thermal stress function is used for investigating thermal buckling. A linear electric function is used for taking external electric voltages into account. For considering the small-scale effect, the modified couple stress theory has been applied. An analytical solution has been used by taking various boundary conditions.

Findings

EEV has a considerable impacted on the results of various half-waves in all boundary conditions. By increasing EEV, the reduction of critical buckling temperature in higher half-waves is remarkably slower than lower half-waves. By considering long lengths, the effect of EEV on the critical temperature will be markedly decreased.

Originality/value

This paper uses electro-thermal stability analysis. Double-layered piezoelectric nanoplates are analyzed. A comprehensive thermal stress function is applied for taking into account critical temperature.

Open Access
Article
Publication date: 3 October 2019

Lin Qi, Wenbo Zhang, Ronglai Sun and Fang Liu

Giant orthogonal grid barrel vault is generated by deleting members in the inessential force transfer path of the two-layer lattice barrel vault. Consisting of members in the…

1372

Abstract

Purpose

Giant orthogonal grid barrel vault is generated by deleting members in the inessential force transfer path of the two-layer lattice barrel vault. Consisting of members in the essential transfer path only, giant orthogonal grid barrel vault is a new type of structure with clear mechanical behavior and efficient material utilization. The paper aims to discuss this issue.

Design/methodology/approach

The geometrical configuration of this structure is analyzed, and the geometrical modeling method is proposed. When necessary parameters are determined, such as the structural span, length, vault rise, longitudinal and lateral giant grid number and section height to top chord length ratio of the lattice member, the structure geometrical model can be generated.

Findings

Numerical models of giant orthogonal grid barrel vaults with different rise–span ratios are built using the member model that can simulate the pre-buckling and post-buckling behavior. So the possible member buckle-straighten process and the plastic hinge form–disappear process of the structure under strong earthquake can be simulated.

Originality/value

Seismic analysis results indicate that when the structure damages under strong earthquake there are a large number of buckling members and few endpoint plastic hinges in the structure. Dynamic damage of giant orthogonal grid barrel vault under strong earthquake is caused by buckling members that weaken the structural bearing capacity.

Details

International Journal of Structural Integrity, vol. 11 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 1 January 1939

F.R. Shanley

MOST of the structural analysis problems that have resulted from the use of “thin‐walled” construction seem to fall into two general classes: Stress distribution and buckling

1117

Abstract

MOST of the structural analysis problems that have resulted from the use of “thin‐walled” construction seem to fall into two general classes: Stress distribution and buckling. Even these classes cannot be entirely separated, as the stress distribution can be greatly affected by buckling phenomena. A thorough understanding of the general principles of buckling (or structural instability) is therefore essential for efficient and safe design of modern aircraft structures.

Details

Aircraft Engineering and Aerospace Technology, vol. 11 no. 1
Type: Research Article
ISSN: 0002-2667

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