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Book part
Publication date: 5 October 2018

Nasir Bedewi Siraj, Aminah Robinson Fayek and Mohamed M. G. Elbarkouky

Most decision-making problems in construction are complex and difficult to solve, as they involve multiple criteria and multiple decision makers in addition to subjective…

Abstract

Most decision-making problems in construction are complex and difficult to solve, as they involve multiple criteria and multiple decision makers in addition to subjective uncertainties, imprecisions and vagueness surrounding the decision-making process. In many instances, the decision-making process is based on linguistic terms rather than numerical values. Hence, structured fuzzy consensus-reaching processes and fuzzy aggregation methods are instrumental in multi-criteria group decision-making (MCGDM) problems for capturing the point of view of a group of experts. This chapter outlines different fuzzy consensus-reaching processes and fuzzy aggregation methods. It presents the background of the basic theory and formulation of these processes and methods, as well as numerical examples that illustrate their theory and formulation. Application areas of fuzzy consensus reaching and fuzzy aggregation in the construction domain are identified, and an overview of previously developed frameworks for fuzzy consensus reaching and fuzzy aggregation is provided. Finally, areas for future work are presented that highlight emerging trends and the imminent needs of fuzzy consensus reaching and fuzzy aggregation in the construction domain.

Details

Fuzzy Hybrid Computing in Construction Engineering and Management
Type: Book
ISBN: 978-1-78743-868-2

Keywords

Article
Publication date: 8 May 2018

Xudong Chen and Andrew Chan

This paper aims to investigate the responses of laminated glass under soft body impact, including elastic impact and fracture/fragmentation consideration.

Abstract

Purpose

This paper aims to investigate the responses of laminated glass under soft body impact, including elastic impact and fracture/fragmentation consideration.

Design/methodology/approach

The simulation uses the combined finite-discrete element method (FDEM) which combines finite element mesh into discrete elements, enabling the accurate prediction of contact force and deformation. Material rupture is modelled with a cohesive fracture criterion, evaluating the process from continua to discontinua.

Findings

Responses of laminated glass under soft impact (both elastic and fracture) agree well with known data. Crack initiation time in laminated glass increases with the increase of the outside glass thickness. With the increase of Eprojectile, failure mode is changing from flexural to shear, and damage tends to propagate longitudinally when the contact surface increases. Results show that the FDEM is capable of modelling soft impact behaviour of laminated glass successfully.

Research limitations/implications

The work is done in 2D, and it will not represent fully the 3D mechanisms.

Originality/value

Elastic and fracture behaviour of laminated glass under soft impact is simulated using the 2D FDEM. Limited work has been done on soft impact of laminated glass with FDEM, and special research endeavours are warranted. Benchmark examples and discussions are provided for future research.

Details

Engineering Computations, vol. 35 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 March 1995

D.R.J. Owen, S.Y. Zhao and J.G. Loughran

A finite element solution to the rolling of two‐phase materials ispresented and applied to the rolling of prepared sugar cane. The generalizedBiot theory is extended and…

Abstract

A finite element solution to the rolling of two‐phase materials is presented and applied to the rolling of prepared sugar cane. The generalized Biot theory is extended and modified to suit the present problem and the velocity of the solid skeleton and the pore pressure are taken as the primary unknowns. The finite element approach is applied to the governing equations for spatial discretization, followed by time domain discretization by standard difference methods. A constitutive relation evaluated from a finite element simulation of experiments performed on a constrained compression test cell is employed. The computational model of the rolling of prepared cane with two rolls is presented. The material parameters of prepared cane are described and their variation during the rolling process are derived and discussed. Numerical results are presented to illustrate the performance and capability of the model and solution procedures.

Details

Engineering Computations, vol. 12 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 March 1988

A. Gens and D.M. Potts

Elasto‐plastic models based on critical state formulations have been successful in describing many of the most important features of the mechanical behaviour of soils…

Abstract

Elasto‐plastic models based on critical state formulations have been successful in describing many of the most important features of the mechanical behaviour of soils. This review paper deals with the applications of this class of models to the numerical analysis of geotechnical problems. After a brief overview of the development of the models, the basic critical state formulation is presented together with the main modifications which have actually been used in computational applications. The problems associated with the numerical implementation of this type of models are then discussed. Finally, a summary of reported computational applications and some specific examples of analyses of geotechnical problems using critical state models are presented.

Details

Engineering Computations, vol. 5 no. 3
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 1 June 1992

L. JENDELE, A.H.C. CHAN and D.V. PHILLIPS

This paper deals with the well known degenerated shell element of Ahmad. The main concern focuses on the rank of the element stiffness matrix and the zero energy modes…

Abstract

This paper deals with the well known degenerated shell element of Ahmad. The main concern focuses on the rank of the element stiffness matrix and the zero energy modes. Element formulation includes geometrical and material non‐linearities. The Lagrangian, heterosis and serendipity variants of displacement approximation are studied using full, selective or reduced in‐plane numerical integration. In the third direction the layered concept is adopted. The obtained results do not fully coincide with those published in References 2 and 3. The Figures presented in this paper, showing the displacement modes, clarify in a convenient form some of the element properties associated with particular element formulations. The work also shows the influence of the plastic and cracked material conditions on the stiffness matrix of the element.

Details

Engineering Computations, vol. 9 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Book part
Publication date: 19 November 2021

Alexandra C. H. Nowakowski, J. E. Sumerau and Lain A. B. Mathers

This chapter explores age-based variations in the healthcare experiences of transgender people. Specifically, we outline how transgender people narrate their experiences…

Abstract

This chapter explores age-based variations in the healthcare experiences of transgender people. Specifically, we outline how transgender people narrate their experiences with coming out and transition in later life as well as possibilities for future research and clinical practice concerning older transgender populations. To this end, we begin with a review of the limited literature on older transgender populations including the ways such findings converge and diverge from studies of younger transgender populations. Then, we analyze data gathered from older transgender people throughout the United States concerning their experiences with health events, healthcare providers, and healthcare settings. For this empirical analysis, we draw on over 250 qualitative responses from transgender people over the age of 40. The findings of this chapter demonstrate the importance of adjusting existing healthcare protocols to provide adequate care for aging transgender populations. Specifically, our analyses highlight gaps in access and quality of healthcare delivery as well as issues related to medical education, trans-inclusive protocols, and sex-gender segregated medical traditions. The implications of our work here reveal important possibilities for expanding transgender healthcare access as well as existing barriers to such access. We specifically utilize the case of our respondents and the existing literature to illuminate gaps in needs assessment and healthcare delivery concerning older transgender populations. We will conclude the chapter with recommendations for bridging such gaps in research, education, and system operation.

Details

Advances in Trans Studies: Moving Toward Gender Expansion and Trans Hope
Type: Book
ISBN: 978-1-80262-030-6

Keywords

Article
Publication date: 1 February 1991

A.H.C. CHAN

For those who are working with the finite element method, one may somehow wonder why a n point Gauss‐Legendre quadrature formula can integrate a 2n—1 order polynomial…

Abstract

For those who are working with the finite element method, one may somehow wonder why a n point Gauss‐Legendre quadrature formula can integrate a 2n—1 order polynomial exactly. The purpose of this note is to unravel the secret.

Details

Engineering Computations, vol. 8 no. 2
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 1 February 1989

A.H.C. Chan

The Lanczos method with the Golub and Kahan bidiagonalization algorithm is used to solve non‐symmetric diagonal dominant simultaneous equations. The method is very…

Abstract

The Lanczos method with the Golub and Kahan bidiagonalization algorithm is used to solve non‐symmetric diagonal dominant simultaneous equations. The method is very suitable for sparse matrix and vector computer. The problem with loss of orthogonal property is dealt with by restating the iteration. Numerical examples together with FORTRAN 77 routine are given to illustrate the algorithm. Both scalar and vector CPU times are given for comparison.

Details

Engineering Computations, vol. 6 no. 2
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 11 June 2021

Jichang Wang and Xiaoming Guo

A mesoscopic phase field (PF) model is proposed to simulate the meso-failure process of lightweight concrete.

253

Abstract

Purpose

A mesoscopic phase field (PF) model is proposed to simulate the meso-failure process of lightweight concrete.

Design/methodology/approach

The PF damage model is applied to the meso-failure process of lightweight concrete through the ABAQUS subroutine user-defined element (UEL). And the improved staggered iteration scheme with a one-pass procedure is used to alternately solve the coupling equations.

Findings

These examples clearly show that the crack initiation of the lightweight concrete specimens mainly occurs in the ceramsite aggregates with weak strength, especially in the larger aggregates. The crack propagation paths of the specimens with the same volume fraction of light aggregates are completely different, but the crack propagation paths all pass through the ceramsite aggregates near the cracks. The results also showed that with the increase in the volume fractions of the aggregates, the slope and the peak loads of the force-deflection (F-d) curves gradually decrease, the load-bearing capacity of the lightweight concrete specimens decreases, and crack branching and coalescence are less likely during crack propagation.

Originality/value

The mesostructures with a mortar matrix, aggregates and an interfacial transition zone (ITZ) are generated by an automatic generation and placement program, thus incorporating the typical three-phase characteristics of lightweight concrete into the PF model.

Details

Engineering Computations, vol. 38 no. 10
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 September 1996

M. Cervera, R. Codina and M. Galindo

Outlines a general methodology for the solution of the system of algebraic equations arising from the discretization of the field equations governing coupled problems…

Abstract

Outlines a general methodology for the solution of the system of algebraic equations arising from the discretization of the field equations governing coupled problems. Considers that this discrete problem is obtained from the finite element discretization in space and the finite difference discretization in time. Aims to preserve software modularity, to be able to use existing single field codes to solve more complex problems, and to exploit computer resources optimally, emulating parallel processing. To this end, deals with two well‐known coupled problems of computational mechanics – the fluid‐structure interaction problem and thermally‐driven flows of incompressible fluids. Demonstrates the possibility of coupling the block‐iterative loop with the nonlinearity of the problems through numerical experiments which suggest that even a mild nonlinearity drives the convergence rate of the complete iterative scheme, at least for the two problems considered here. Discusses the implementation of this alternative to the direct coupled solution, stating advantages and disadvantages. Explains also the need for online synchronized communication between the different codes used as is the description of the master code which will control the overall algorithm.

Details

Engineering Computations, vol. 13 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

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