scholarly journals Leslie Sydney Dennis Morley FREng FRAeS. 23 May 1924 — 16 June 2011

2016 ◽  
Vol 62 ◽  
pp. 433-445
Author(s):  
A. J. Morris
Keyword(s):  
Finite Element ◽  
Shell Theory ◽  
Metal Structure ◽  
Singular Solutions ◽  
The Finite Element Method ◽  
Structural Behaviour ◽  
First Order ◽  
Plates And Shells ◽  
Shell Equation ◽  
Nonlinear Regimes

Leslie Morley's research focused on modelling structural behaviour, with particular emphasis on plates and shells. He developed the Morley shell equation, which has been acknowledged as the simplest equation consistent with first-order shell theory. As the finite element method rose to prominence he developed elements for both plates and shells. He then worked on developing a set of new finite elements able to handle complex shell behaviour in both the linear and nonlinear regimes. He also observed that it was possible to augment the finite element solution by using singular solutions to calculate the stress intensity factor at a crack tip in a thin-walled metal structure and thereby to compute crack propagation rates. In undertaking his research Morley probed into the mathematical and physical depths of the problems he confronted, and produced some outstanding and significant results.

scholarly journals Modelling Plates and Shells by Means of the Rigid Finite Element Method

2015 ◽  
Vol 62 (1) ◽  
pp. 101-114 ◽  
Author(s):  
Iwona Adamiec-Wójcik ◽  
Andrzej Nowak ◽  
Stanisław Wojciech
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Free Vibrations ◽  
The Finite Element Method ◽  
Hybrid Finite Element Method ◽  
Hybrid Finite Element ◽  
Rigid Finite Element Method ◽  
Plates And Shells ◽  
Single Set ◽  
Element Method

Abstract The rigid finite element method (RFEM) has been used mainly for modelling systems with beam-like links. This paper deals with modelling of a single set of electrodes consisting of an upper beam with electrodes, which are shells with complicated shapes, and an anvil beam. Discretisation of the whole system, both the beams and the electrodes, is carried out by means of the rigid finite element method. The results of calculations concerned with free vibrations of the plates are compared with those obtained from a commercial package of the finite element method (FEM), while forced vibrations of the set of electrodes are compared with those obtained by means of the hybrid finite element method (HFEM) and experimental measurements obtained on a special test stand.

Redesign of Structural Vibration Modes by Finite-Element Inverse Perturbation

1981 ◽  
Vol 103 (2) ◽  
pp. 319-325 ◽  
Author(s):  
K. A. Stetson ◽  
I. R. Harrison
Keyword(s):  
Finite Element ◽  
Equations Of Motion ◽  
Structural Vibration ◽  
Vibration Modes ◽  
Element Analysis ◽  
Jet Engine ◽  
First Order ◽  
Plate Elements ◽  
Plates And Shells ◽  
First Order Perturbation

A previously developed technique for redesigning the vibrational properties of structures, by inverting the first-order perturbation analysis of the equations of motion, has been applied to a NASTRAN finite element analysis for plates and shells. The program finds the minimal changes to the thicknesses of the plate elements necessary to effect a given set of changes in the modal frequencies and shapes. Results have been obtained for a flat cantilever plate, a cantilever segment of a cylinder, and for a compressor blade for a jet engine.

A New Method to Quickly Optimize the Thickness of Multi-Holes Plate

2014 ◽  
Vol 915-916 ◽  
pp. 205-208
Author(s):  
Sheng Bin Wu ◽  
Xiao Bao Liu
Keyword(s):  
Mathematical Model ◽  
Finite Element Method ◽  
Finite Element ◽  
Design Method ◽  
New Method ◽  
The Finite Element Method ◽  
Design Error ◽  
Theory Of Plates ◽  
Plates And Shells ◽  
Element Method

The theory of plates and shells is not adapted to design thickness for the multi-holes plates in engineering. A new method to quickly optimize the thickness based on the finite element method theory was put forward. The method combined the theory of plate with the finite element method to establish a mathematical model and analyzed the influences of load, constraint and complexity on design error. The practices demonstrated that the proposed design method is effective and feasible.

Use of Finite Element Method in Optimization of Quay Crane's Grab

2013 ◽  
Vol 837 ◽  
pp. 346-350
Author(s):  
Cristina Dragomir
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Permanent Deformation ◽  
Metal Structure ◽  
The Finite Element Method ◽  
Element Analysis ◽  
Modeling And Analysis ◽  
Quay Cranes ◽  
Tie Rods ◽  
Element Method

This Finite element method is one of the most advanced calculating methods for approximation of accurate solutions to engineering problems. Optimization of grabs quay cranes is necessary because most port operators use this type of equipment for loading and unloading bulk cargo. Initial research methods applied in this study are based on observations and surveys conducted on Bocşa 16 t - 32 m mobile quay cranes of MinMetal S.A. Constanta port operator. Modeling and analysis for grabs structure optimization was made with FEMAP and NX NASTRAN - version 10.3.1 applications, which use the finite element method and finite element analysis. After calculations and analysis, the following optimizations resulted:-to increase the grabs closing force (in order to minimize the loss of cargo between jaws and to increase digging force) the lower beam weight must be reduced.-to reduce the amount of cargo drained from the grabs jaws at loading, rubber jaws barriers can be fixed or bars can be welded at grabs jaws.- if cargo has high granulation, in order to reduce grabs weight the plate of the jaw can be cropped.-cups supporting tie rods could be replaced by hydraulic cylinders.The greatest tension is located in the cups supportive arms and in the area where cups are attached to arms. Shafts tensions are larger than the grabs metal structure and are located in shafts-arms contact areas, ie support bearings. In these areas, an optimization can be made by installing ball bearings to reduce friction. The largest deformations occur in the middle area of the arms. To increase safety in operation it is necessary to change the material of the four arms supporting cups, given that deformation of 89.7 mm (~ 9 cm) combined with external factors and / or shock loads can lead to permanent deformation or even material breaks. After changing the material, the model showed that the deformations in the middle area of the arms are substantially reduced, at only 4 mm. In the contact area of the upper arms with the two bars of the upper beam, hazardous tensions may be minimized if there are inserted bearings.

Structural Effects of Brick Arrangement and Span Length on Mid-Pointed Arches

2010 ◽  
Vol 133-134 ◽  
pp. 411-416 ◽  
Author(s):  
Mehrdad Hejazi ◽  
Farshad Jafari
Keyword(s):  
Finite Element ◽  
Brick Masonry ◽  
The Finite Element Method ◽  
Structural Effects ◽  
Structural Behaviour ◽  
Masonry Arches ◽  
Masonry Arch ◽  
Persian Architecture ◽  
Element Technique ◽  
Structural Engineers

One of the most important, valuable and remarkable elments of Persian architecture is brick masonry arch. Structural behaviour of Persian brick masonry arches has not been studied in details. Any investigation into their characteristics can be beneficial for maintenance, retrofit, restoration and reconstruction of such arches. The effect of a brick arrangement in the fabric of arches, such as Roman and barrel arrangements, on structural behaviour of brick masonry arches has been a serious controversy among architects and structural engineers for many years. In this study, micro-modelling finite element technique has been used to analyse mid-pointed arches with two different brick arrangements, i.e. Roman and barrel arrangements, under static weight load using the finite element method. Analyses have been carried out and obtained results have been discussed to describe the effect of brick arrangement on structural behaviour of analysed arches with three different span lengths.

scholarly journals Error control in FORM reliability analysis

2012 ◽  
Author(s):  
Laurent Gallimard
Keyword(s):  
Finite Element ◽  
Error Control ◽  
Sampling Technique ◽  
Error Estimator ◽  
The Finite Element Method ◽  
Element Mesh ◽  
First Order Reliability Method ◽  
First Order ◽  
Reliability Method ◽  
Importance Sampling Technique

This paper deals with the failure probability error induced by the coupling between the first-order reliability method (FORM) and the Finite Element Method (FEM). A FEM error estimator based on the concept of error in constitutive relation associated with goal-oriented error estimation is proposed. Furthermore an importance sampling technique is used to compute the error due to the FORM approximation. Both these errors are used to choose a finite element mesh adapted to the problem.

Structural design of high-speed rolling bearing test rig spindle with cantilever

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hui Li ◽  
Hao Li ◽  
Rongfeng Zhang ◽  
Yi Liu ◽  
Shemiao Qi ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Critical Speed ◽  
Testing Machine ◽  
Structure Design ◽  
Installation Space ◽  
The Finite Element Method ◽  
Content Type ◽  
First Order ◽  
Element Method

Purpose The purpose of this paper is to introduce the structure design process of the cantilever spindle with limited installation space and wishing to increase its critical speed. Design/methodology/approach In this paper, the finite element method was used to analyze the influence of the supporting stiffness and the structure of the spindle on the critical speed, and then the structure of the spindle was designed; moreover, the experiment was accomplished and the experiment results show that the spindle can work stably. Findings Through analyzing the influence of the supporting stiffness and the structure of the spindle on the critical speed, the following conclusions could be obtained: the shape of the first-mode is the bend vibration of the cantilever of the spindle; the first-order critical speed of the spindle gradually decreases with the diameter and length of the cantilever increasing; the first-order critical speed of the spindle increases with the depth and diameter of the blind hole increasing; and the experiment was accomplished and the experiment results show that the spindle can work stably. Originality/value In this paper, the finite element method was used to design the spindle of the testing machine, and satisfactory results were obtained. It can provide a theoretical reference for the design of a similar spindle.

scholarly journals Finite element analysis of Bridge Crane Metal Structure Based on ABAQUS

2018 ◽  
Vol 198 ◽  
pp. 01004
Author(s):  
Zhong Meng ◽  
Tong Yifei ◽  
LI Xiangdong
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Metal Structure ◽  
Design Parameters ◽  
Bridge Crane ◽  
The Finite Element Method ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Operation Conditions ◽  
Element Method

Taking the QD-type (50/10t-31.5) bridge crane as the research object and the finite element method as theoretical basis, the metal structure using ABAQUS software is analyzed. Firstly, the three-dimensional model of the metal structure is established according to the design parameters. Second, the bridge crane under three typical operation conditions is analyzed and the stress and displacement analysis results are presented. And, the strength and stiffness of the crane are verified based on the analysis results. Moreover, the maximum stress and displacement under dangerous conditions of the crane are calculated by theoretical calculation. By comparing the results of the theoretical method and the finite element method. The research can favor to increase the design efficiency.

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