Jeffrey Doyon

HW#2

Due 10/20/08

List of References:

(a) Callister, William D. (2000). Materials Science And Engineering, An Introduction, 5th Edition. John Wiley & Sons, Inc.

(b) Budynas, Richard G. (1999). Advanced Strength and Applied Stress Analysis, 2nd Edition. McGraw-Hill.

1. The Airy stress function Ф(x,y) is applicable to 2D plane elasticity problems where body forces don’t exist, and is defined such that:

Solving for compatibility yields the biharmonic equation:

Written out for rectangular coordinates, this biharmonic equation is:

2.From the notes, for an isotropic linear elastic solid,

Values of E or υ are given for this problem as stated below.

E = 210 GPa

υ = .3

from Ref (b)


#3. A 2D plate element model was created using PATRAN software that represented linear-elastic (small deflections), isotropic material. All nodes at x=0 were fixed (All DOFs=0), and a point load of 105 was applied to one node at the edge of the beam (at x=1) and in the middle of the breadth (at z=0.5). Below the deflected shape is represented in red and the undelfected shape is in black. The predicted maximum deflection is 0.00358.

,

=-.004 From Beam Theory closed form solution.


#4.a and b

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4c.

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4d. If there is not stress then there is no strain as they are directly proportional in linear elastic theory.

4e. See 4c.

4.g

4.f

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5.a The solutions seen below can be obtain from the notes.

b.

c.

d.

Sigma_z=0

E.

Hoop stress

Displacement

Sigma_r

Esilon_phi

Epsilon_r

6.a Creep compliance is equal to the ratio of elasticity to anelatisity or E/neta.

b. Assume propertie of steel. E=30X10^6psi=206842MPa. Assume strain an instant before the stress is released at t=10^3