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1 – 10 of over 8000Gives 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.
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Mohannad Naser and Venkatesh Kodur
This paper aims to present results from numerical studies on the response of fire exposed composite girders subjected to dominant flexural and shear loading. A finite…
Abstract
Purpose
This paper aims to present results from numerical studies on the response of fire exposed composite girders subjected to dominant flexural and shear loading. A finite element-based numerical model was developed to trace the thermal and structural response of composite girders subjected to simultaneous structural loading and fire exposure. This model accounts for various critical parameters including material and geometrical nonlinearities, property degradation at elevated temperatures, shear effects, composite interaction between concrete slab and steel girder, as well as temperature-induced local buckling. To generate test data for validation of the model, three composite girders, each comprising of hot-rolled (standard) steel girder underneath a concrete slab, were tested under simultaneous fire and gravity loading.
Design/methodology/approach
The validated model was then applied to investigate the effect of initial geometric imperfections, load level, thickness of slab and stiffness of shear stud on fire response of composite girders.
Findings
Results from experimental and numerical analysis indicate that the composite girder subjected to flexural loading experience failure through flexural yielding mode, while the girders under shear loading fail through in shear web buckling mode. Further, results from parametric studies clearly infer that shear limit state can govern the response of fire exposed composite girders under certain loading configuration and fire scenario.
Originality/value
This paper presents results from numerical studies on the response of fire exposed composite girders subjected to dominant flexural and shear loading.
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CONSIDER a fuselage or wing structure in the form of a reinforced cylindrical tube. We shall base our analysis of the equilibrium conditions of this structure upon the assumptions…
Abstract
CONSIDER a fuselage or wing structure in the form of a reinforced cylindrical tube. We shall base our analysis of the equilibrium conditions of this structure upon the assumptions outlined in 2.6. In particular referring in the first place to a skin panel lying between adjacent stringers and rings, we remark that this panel carries only shear stresses and is free from external forces. It follows, as we have observed before, that this panel must therefore be in a state of uniform shearing and so must apply uniform shear flows at its lines of juncture with the adjacent panels and the reinforcing stringers and rings. The equilibrium conditions to be satisfied at a stringer‐skin joint are now clear. The panels adjacent to the stringer apply different, but uniform, shear flows, to the line of attachment. The reaction from the stringer is determined by the rate of variation of its end load, for this clearly gives the rate of load input into the stringer. Adopting a consistent sign convention for the shear flows in the several skin panels we can thus enunciate the following theorem:
The purpose of this paper is to provide a summarization and review of the present author's main investigations on failure modes of reticular metal foams under different loadings…
Abstract
Purpose
The purpose of this paper is to provide a summarization and review of the present author's main investigations on failure modes of reticular metal foams under different loadings in engineering applications.
Design/methodology/approach
With the octahedral structure model proposed by the present authors themselves, the fundamentally mechanical relations have been systematically studied for reticular metal foams with open cells in their previous works. On this basis, such model theory is continually used to investigate the failure mode of this kind of porous materials under compression, bending, torsion and shearing, which are common loading forms in engineering applications.
Findings
The pore-strut of metal foams under different compressive loadings will fail in the tensile breaking mode when it is brittle. While it is ductile, it will tend to the shearing failure mode when the shearing strength is half or nearly half of the tensile strength for the corresponding dense material and to the tensile breaking mode when the shearing strength is higher than half of the tensile strength to a certain value. The failure modes of such porous materials under bending, torsional and shearing loads are also similarly related to their material species.
Originality/value
This paper presents a distinctive method to conveniently analyze and estimate the failure mode of metal foams under different loadings in engineering applications.
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Abhishek K. Singh, Anirban Lakshman and Amares Chattopadhyay
The response of moving load over a surface is a subject of investigation because of its possible applications in determining the strength of a structure. Recently, with the…
Abstract
Purpose
The response of moving load over a surface is a subject of investigation because of its possible applications in determining the strength of a structure. Recently, with the enlargement of high-speed train networks, concern has been expressed about the effects of moving loads on the track, embankment and nearby structures. Earth surface and artificial structure are not always regular in nature. Irregularities are also responsible for structural collapse of long bridge and highway of plateau area under the action of moving loads. The purpose of this paper is to investigate the influence of irregularity on dynamic response due to a moving shear load.
Design/methodology/approach
At first the authors developed the mathematical model for the problem which is comprised of equation of motion together with boundary conditions. Perturbation technique has been used to derive the stresses produced in an irregular orthotropic half-space (which is influenced by gravity) due to a moving shear load. MATLAB and MATHEMATICA softwares have been employed for numerical computation as well as graphical illustration.
Findings
In this paper the authors have discussed the stresses produced in an irregular gravitating orthotropic half-space due to a moving shear load. The expression for shear stress has been established in closed form. Substantial effects of depth, irregularity factor, maximum depth of irregularity and gravitational parameter on shear stress have been reported. These effects are also exhibited by means of graphical illustration and numerical computation for an orthotropic material T300/5208 graphite/epoxy which is broadly used in aircraft designing. Moreover, comparison made through meticulous examination for different types of irregularity, presence and absence of anisotropy and gravity are highlighted.
Practical implications
A number of classical fatigue failures occur in aircraft structures. The moving load responsible for such fatigue failure may occur during manufacturing process, servicing, etc. Apart from these the aircraft structures may also experience load because of environmental damages (such as lightning strike, overheat) and mechanical damages (like impact damage, overload/bearing failure). Therefore the present study is likely to find application in the field of construction of highways, airport runways and earthquake engineering.
Originality/value
To the best of the authors’ knowledge no problem related to moving load on irregular orthotropic half-space under influence of gravity has been attempted by any author till date. Furthermore comparative study for different types of irregularity, presence and absence of anisotropy and influence of gravity on the dynamic response of moving load are novel and major highlights of the present study.
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Jiawei Wang, Jinliang Liu, Guanhua Zhang and Jigang Han
Considering the “size effect” and the properties degradation of building materials on the strengthened engineering, in this paper, the technology of pasting steel plate was…
Abstract
Purpose
Considering the “size effect” and the properties degradation of building materials on the strengthened engineering, in this paper, the technology of pasting steel plate was adopted to shear strengthen a 16 m prestressed concrete hollow slab, which had serviced 20 years in cold regions. The shear properties of shear strengthen beams are analyzed.
Design/methodology/approach
Shear loading test of the shear strengthened beam and the contrast beam was conducted. Then the mechanical characteristics, failure mechanism, the mechanical response and shear capacity of shear strengthened beam and contrast beam had been discussed.
Findings
The failure mode of shear strengthened beam and contrast beam was shear compression failure, and the bond failure between concrete and prestressed reinforcement happened in both of test beams. The shear strengthening method of pasting steel plate can effectively improve the mechanical response for the shear strengthened beam. Compared with the contrast beam, the cracking load and failure shear capacity for the shear strengthened beam can be effectively increased by 12.2 and 27.6%, respectively.
Originality/value
The research results can be a reference for the detection and evaluation of shear strengthened bridges, which are strengthened by pasting steel plate. Engineers can refer to the shear strengthening method in this paper to strengthen the existing bridge, which can guarantee the safety of shear strengthened bridges.
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A DSIR Sponsored Research Programme on the Development and Application of the Matrix Force Method and the Digital Computer. This work presents a rational method for the structural…
Abstract
A DSIR Sponsored Research Programme on the Development and Application of the Matrix Force Method and the Digital Computer. This work presents a rational method for the structural analysis of stressed skin fuselages for application in conjunction with the digital computer. The theory is a development of the matrix force method which permits a close integration of the analysis and the programming for a computer operating with a matrix interpretive scheme. The structural geometry covered by the analysis is sufficiently arbitrary to include most cases encountered in practice, and allows for non‐conical taper, double‐cell cross‐sections and doubly connected rings. An attempt has been made to produce a highly standardized procedure requiring as input information only the simplest geometrical and elastic data. An essential feature is the use of the elimination and modification technique subsequent to the main analysis of the regularized structure in which all cutouts have been filled in. Current Summary A critical historical appraisal of previous work in the Western World on fuselage analysis is given in the present issue together with an outline of the ideas underlying the new theory.
The following items were examined:
Fatimah De’nan, Nor Salwani Hashim, Xing Yong Sua and Pui Yee Lock
Due to economic development, tapered members are commonly applied in steel frames, namely, industrial halls, warehouses, exhibition centres, etc. In the design of cantilever steel…
Abstract
Purpose
Due to economic development, tapered members are commonly applied in steel frames, namely, industrial halls, warehouses, exhibition centres, etc. In the design of cantilever steel beam structures in cities building design, tapering is introduced at the web profile to achieve utmost economy and suit the bending moment distributions. The cross-sectional shape of the beam is varied linearly to the moment gradient to achieve the target of higher efficiency with lower cost.
Design/methodology/approach
The shear deformation pattern and efficiency of the tapered steel section with perforation were investigated using finite element analysis. In addition, I-beam with web opening is studied numerically via LUSAS software for different parameters of tapering ratio, perforation shape and perforation size and perforation layout.
Findings
The highest contributing parameters for the highest shear buckling capacity and efficiency of the section were due to the small opening size and tapering ratio. Whilst the variation of perforation layout and spacing give a major effect on the shear strength and efficiency of the tapered steel section with perforation. Besides that, the highest efficiency model is found when the section is designed with 0.4 D diamond perforation in Layout 3 under a tapering ratio of 0.3. The critical shear buckling load and efficiency is reduced 14.39% and 13.91%, respectively, when perforations are added onto the tapered steel sections.
Originality/value
The tapered steel section with perforation has lower critical shear buckling load and efficiency compared to the tapered section without perforation but obtains a higher critical shear buckling load and efficiency compared to the uniform section without perforation.
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Python codes are developed for the versatile structural analysis on a 3 spar multi-cell box beam by means of idealization approach.
Abstract
Purpose
Python codes are developed for the versatile structural analysis on a 3 spar multi-cell box beam by means of idealization approach.
Design/methodology/approach
Shear flow distribution, stiffener loads, location of shear center and location of geometric center are computed via numpy module. Data visualization is performed by using Matplotlib module.
Findings
Python scripts are developed for the structural analysis of multi-cell box beams in lieu of long hand solutions. In-house developed python codes are made available to be used with finite element analysis for verification purposes.
Originality/value
The use of python scripts for the structural analysis provides prompt visualization, especially once dimensional variations are concerned in the frame of aircraft structural design. The developed python scripts would serve as a practical tool that is widely applicable to various multi-cell wing boxes for stiffness purposes. This would be further extended to the structural integrity problems to cover the effect of gaps and/or cut-outs in shear flow distribution in box-beams.
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