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Explore solutions to plane elasticity problems using Biharmonic equations, beam bending under various loadings, stress fields, and more. Theoretical concepts and practical applications are covered in depth.
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Application Solutions of Plane Elasticity Professor M. H. Sadd
Airy Representation y x Biharmonic Governing Equation Traction Boundary Conditions S R Solutions to Plane ProblemsCartesian Coordinates
y T T 2c x 2l Uniaxial Tension of a Beam
y M 2c M x 2l Pure Bending of a Beam Note Integrated Boundary Conditions
w wl wl 2c x y l/c = 2 l/c = 3 l/c = 4 Dimensionless Distance, y/c 2l x/w - Elasticity x/w - Strength of Materials Bending of a Beam by Uniform Transverse Loading
w wl wl 2c x y 2l Bending of a Beam by Uniform Transverse Loading Note that according to theory of elasticity, plane sections do not remain plane For long beams l >>c, elasticity and strength of materials deflections will be approximately the same
y P x N 2c L Cantilever Beam Problem Displacement Field Stress Field
p x A B L y Cantilever Tapered Beam Stress Field x = L x = L
Airy Representation Biharmonic Governing Equation Traction Boundary Conditions S R y r x Solutions to Plane ProblemsPolar Coordinates
p2 r1 p1 r2 r1/r2 = 0.5 /p r /p r/r2 Dimensionless Distance, r/r2 Thick-Walled Cylinder Under Uniform Boundary Pressure Internal Pressure Case
y a T T x r/a Stress Free Hole in an Infinite Medium Under Uniform Uniaxial Loading at Infinity
T T T T T T Unaxial Loading T Biaxial Loading T T Biaxial Loading Stress Concentrations for Other Loading Cases K=3 K=2 K=4
y a x b Stress Concentration Around Elliptical Hole ()max/S Circular Case (K=3)
Y X x r C y xy/(Y/a) y/(Y/a) Dimensionless Distance, x/a Half-Space Under Concentrated Surface Force System (Flamant Problem) Normal Loading Case (X=0) y = a
y r x = 2 - Notch-Crack Problems Contours of Maximum Shear Stress
Two-Dimensional FEA Code MATLAB PDE Toolbox • - Simple Application Package For Two-Dimensional Analysis Initiated by Typing “pdetool” in Main MATLAB Window • Includes a Graphical User Interface (GUI) to: - Select Problem Type - Select Material Constants - Draw Geometry - Input Boundary Conditions - Mesh Domain Under Study - Solve Problem - Output Selected Results
FEA Notch-Crack Problem (vonMises Stress Contours)
P r a b Theory of Elasticity Strength of Materials a/P = /2 b/a = 4 Dimensionless Distance, r/a Curved Beam Problem
Disk Under Diametrical Compression P = D P Flamant Solution (1) + + Radial Tension Solution (3) Flamant Solution (2)
y P r1 1 x r2 2 P Disk Under Diametrical Compression = + +
Photoelastic Contours Theoretical Contours of Maximum Shear Stress Finite Element Model(Distributed Loading) (Courtesy of Dynamic Photomechanics Laboratory, University of Rhode Island) Disk ResultsTheoretical, Experimental, Numerical