The Photoelastic Analysis of Transverse Bending of Plates in the Standard Transmission Polariscope

1942 ◽  
Vol 9 (4) ◽  
pp. A161-A164
Author(s):  
D. C. Drucker
Keyword(s):  
Thick Plate ◽  
Three Dimensional ◽  
Similar Material ◽  
Photoelastic Method ◽  
Initial Tension ◽  
Transverse Bending ◽  
Photoelastic Analysis ◽  
Concentration Factors ◽  
Usual Theory ◽  
Stress Concentration Factors

Abstract In this paper the ideas of three-dimensional photo-elasticity are applied to the analysis of plates under transverse bending, resulting in a simple photoelastic method, employing the standard two-dimensional transmission polariscope. The procedure used is to “freeze” a fairly high initial tension in bakelite or similar material, cut out the model at some angle to the direction of the tension, bend, and observe. Results of various tests are given; photographs of two cases, the circular hole and the semicircular notch, are included. Stress-concentration factors are also obtained and analyzed. The problem of the thick plate as contrasted with the thin plate, assumed in the usual theory, is discussed briefly.

Stress-Concentration Factors for a Countersunk Hole in a Flat Bar in Tension and Transverse Bending

1978 ◽  
Vol 45 (4) ◽  
pp. 929-932 ◽  
Author(s):  
Y. F. Cheng
Keyword(s):  
Stress Concentration ◽  
Stress Concentration Factor ◽  
Concentration Factor ◽  
Maximum Stress ◽  
Three Dimensional ◽  
Neutral Plane ◽  
Transverse Bending ◽  
Concentration Factors ◽  
Stress Concentration Factors ◽  
Maximum Stresses

A series of three-dimensional photoelastic experiments was performed to determine the maximum stresses and stress-concentration factors at countersunk holes in a flat bar in tension and transverse bending. In the tension case, the maximum stress was found at the base of the countersunk and the stress-concentration factor was approximately 33 percent higher than those found in a straight hole. In the bending case, the neutral plane was shifted toward the surface containing the straight part of the hole and the stress-concentration factor was practically the same as those found in straight holes.

Fatigue Assessment of Dented Rigid Risers

2019 ◽  
Author(s):  
Elvis J. O. Santander ◽  
Bianca Pinheiro ◽  
Carlos Magluta ◽  
Ney Roitman
Keyword(s):  
Stress Concentration ◽  
Structural Integrity ◽  
Three Dimensional ◽  
Element Model ◽  
Oil Fields ◽  
Dimensional Finite Element ◽  
Concentration Factors ◽  
Stress Concentration Factors ◽  
Three Dimensional Finite Element ◽  
Remaining Fatigue Life

Abstract In the development of oil fields, submarine pipelines are used in various applications. These pipelines and risers are subject to accidents that may occur during operation, such as shocks between risers or shocks between a riser and an anchor, rock, or any equipment or heavy object, which may cause mechanical failure, such as dents. The objective of this work is to study of the effect of the introduction of plain dents on the structural integrity of rigid risers under fully reversed bending. A three dimensional finite element model was developed to estimate the stress concentration on dented risers under bending. Several numerical simulations were carried out to evaluate stress concentration factors (SCFs) for varying dimensions of dents and risers, in a parametric study. These SCFs can be used in the prediction of the remaining fatigue life of dented rigid risers.

The Prediction of Three-Dimensional Stress Concentration Factors

1959 ◽  
Vol 63 (585) ◽  
pp. 549-551 ◽  
Author(s):  
I. M. Allison
Keyword(s):  
Stress Concentration ◽  
Mathematical Analysis ◽  
Three Dimensional ◽  
Stress Raiser ◽  
Two Dimensions ◽  
Two Dimensional ◽  
Torsional Loading ◽  
Loading System ◽  
Concentration Factors ◽  
Stress Concentration Factors

Two-Dimensional Stress concentration factors may be obtained more quickly and simply than the corresponding three-dimensional factors, either by experiment or mathematical analysis. It would be convenient to obtain information, for varying geometry in the two-dimensional case of a particular type of stress raiser, e.g. a shoulder, groove or hole, and use this either to predict the three-dimensional stress concentration factors or to extend the range of existing three-dimensional results. Clearly a comparison is only possible if the three-dimensional stress raiser embodies a plane of symmetry (which gives the geometry of the similar two-dimensional stress raiser), and if the loading conditions can be reproduced in both the two- and three-dimensional cases. The latter requirement restricts the correlation to the stress concentration factors obtained in tension and in bending. The three-dimensional torsional loading system has no plane of symmetry which can be simulated in two dimensions.

scholarly journals DESCRIBING STRESS CONCENTRATION FACTORS OF AN INTERNALLY PRESSURIZED CYLINDER WITH AN IMBEDDED HOLE BY NEW FORMULATION

2020 ◽  
Author(s):  
javad jafari fesharaki
Keyword(s):  
Stress Concentration ◽  
Three Dimensional ◽  
Fe Analysis ◽  
Internal Diameter ◽  
Concentration Factors ◽  
Stress Concentration Factors ◽  
New Formulation ◽  
Von Mises ◽  
Von Mises Stresses ◽  
Pressurized Cylinder

The purpose of this paper is to investigate the stress concentration factor(SCF) for an internallypressurized cylinder with hole and based on detailed three-dimensional elastic FE analysis, a newcomprehensive set of formulas for SCFs are proposed. These stress concentration factors are presentedand discussed as a function of the ratio of cylinder diameter to the thickness of cylinder and hole diameter.The first ratio “D/100t” is equal to 1, 1.25, 1.5, 1.75, 2, 2.5, 2.75, 3, 3.25 and 3.5 and the second ratio“D/10d”, cylinder internal diameter to the hole diameter, varies from 0.6, 0.9, 1.2, 1.5, 1.8, 2, 2.3, 2.7,3.1and 3.5. Results are also presented for SCF of longitudinal, circumferential and Von Mises stresses.

Using the Palm Computer to Augment the Design of Machine Elements

2000 ◽  
Author(s):  
Terry E. Shoup
Keyword(s):  
Stress Concentration ◽  
Stress Analysis ◽  
Three Dimensional ◽  
The Other ◽  
Machine Design ◽  
State Of Stress ◽  
Machine Elements ◽  
Concentration Factors ◽  
Stress Concentration Factors ◽  
Computational Processes

Abstract This paper discusses the utility of the palm sized computers for augmenting the design of machine elements. Two palm computer programs are presented for handling frequently occurring problems in stress analysis in order to demonstrate the utility of the palm computer in this environment. One of these programs handles the manipulation of a three dimensional state of stress and the other program handles stress concentration factors. These modules facilitate computational processes that would not be possible with a traditional hand-held calculator. These programs are useful for students of machine design and practitioners as well.

Photoelastic Investigation of a Thick Plate With a Transverse Crack

1975 ◽  
Vol 42 (1) ◽  
pp. 9-14 ◽  
Author(s):  
G. Villarreal ◽  
G. C. Sih ◽  
R. J. Hartranft
Keyword(s):  
Plane Stress ◽  
Thick Plate ◽  
Three Dimensional ◽  
Stress Variation ◽  
Thick Plates ◽  
Stress Components ◽  
Photoelastic Investigation ◽  
Photoelastic Analysis ◽  
Moderately Thick Plates ◽  
Transverse Variation

The purpose of this investigation was to experimentally test one of the assumptions of a recent modified version of the theory of generalized plane stress. The form postulated by the theory for the stress variation through the thickness of a plate containing a crack will be compared with that obtained by three-dimensional photoelastic analysis. Specimens covering the range from thin to moderately thick plates were examined by the frozen stress technique. The experimentally measured transverse variation of the in-plane stress components σx and σy was in excellent agreement with that postulated by the theory.

Three-dimensional photoelastic analysis in axially loaded thick plate with hole

1973 ◽  
Vol 8 (3) ◽  
pp. 220-227 ◽  
Author(s):  
N A Rubayi ◽  
V Yadava
Keyword(s):  
Circular Hole ◽  
Thick Plate ◽  
Maximum Stress ◽  
Three Dimensional ◽  
Tensile Loading ◽  
Stress Concentrations ◽  
Precise Location ◽  
Stress Variation ◽  
Photoelastic Analysis ◽  
Different Thickness

In this study three-dimensional photoelasticity is used to analyse the stress variation through different layers of a thick plate containing a circular hole and subjected to uniform tensile loading. The effect of the thickness/diameter ratios on the stress concentrations with thickness is investigated. The experimental results are correlated with the existing three-dimensional theoretical solutions. The data establish, both experimentally and theoretically, the precise location of the maximum-stress layers in plates having different thickness/diameter ratios and thus resolves the discrepancies which existed in previous studies.

Studies in Three-Dimensional Photoelasticity: Stresses in Bent Circular Shafts With Transverse Holes—Correlation With Results From Fatigue and Strain Measurements

1944 ◽  
Vol 11 (1) ◽  
pp. A10-A16
Author(s):  
M. M. Frocht
Keyword(s):  
Stress Concentration ◽  
Three Dimensional ◽  
Fatigue Tests ◽  
Pure Bending ◽  
Simple Method ◽  
Strain Measurements ◽  
Concentration Factors ◽  
Stress Concentration Factors ◽  
Considerable Work ◽  
Maximum Stresses

Abstract Bent circular shafts with holes in the plane of bending are of frequent occurrence in modern machines. They often form a part of the lubricating system as, for example, in the crankshafts of aircraft engines. Considerable work has been done to determine the maximum stresses and the factors of stress concentration in such shafts. The author presents a simple method of calculating such stresses for transverse holes in pure bending. Experimental photoelastic evidence that led to this method is given. A comparison of the stress-concentration factors obtained by it is made with the published results from fatigue tests and strain measurements from large steel shafts, which were performed a number of years ago at the Westinghouse Research Laboratories.

Determination of stress concentration factors for shafts under tension

2020 ◽  
Vol 62 (4) ◽  
pp. 413-421
Author(s):  
Murat Tolga Ozkan ◽  
Fulya Erdemir
Keyword(s):  
Stress Concentration ◽  
Three Dimensional ◽  
Circular Cross Section ◽  
Numerical Data ◽  
Practical Method ◽  
Ann Model ◽  
Element Analysis ◽  
Design And Optimization ◽  
Concentration Factors ◽  
Stress Concentration Factors

Abstract Computer-based design and optimization have become increasingly important in recent years. This paper has investigated the stress concentration factors (SCF) Kt for shoulder filleted shafts with a hole and without a hole. This study contains two types of shoulder filleted shafts, i. e., a stepped bar of circular cross section with shoulder filleted and a tube with filleted shafts under tension stresses. Investigations on SCF that have been carried out in experimental and theoretical studies, were updated and validated for 2 types of shafts. The charts have been converted into numerical value using high precision computer techniques. Dimensional ratios and SCF were determined using previous work charts. This study determines maximum stresses for shoulder filleted shafts by three dimensional finite element analysis (FEA) and artificial intelligence techniques. A set of SCF charts was converted into numerical values and this data was organized and stored in an Excel file. ANSYS models were created and applied the boundary conditions on the models. And also mesh optimizations were performed. Artificial neural networks (ANN) models were designed using previously collected and verified data. Previous works, ANSYS and ANN results were compared to each other. As a result, ANN model and chart results show a good agreement. The usage of ANN model does not require any mathematical formulae or converting the numerical data action for determining the Kt result for shafts. ANN model usage was identified as a very useful and practical method.

Sign in / Sign up

Export Citation Format

Share Document