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PROBLEM (*8.135) The strain readings at a point on the free surface of a steel bracket subjected
to plane stress (see Fig. 8.134) are
ε a = 400 μ
ε b = 350 μ
for
θa
= 0o,
θb
= 45°, and
θc
εc
= 800 μ
= 135°. Calculate:
(a) The maximum in-plane shearing strains.
(b) The true maximum shear strain (ν = 1/3).
Show the results found in part (a) on properly oriented distorted element.
*SOLUTION
Equations (8.43): ε x = 400 μ
350 = ε x (0.5) + ε y (0.5) + γ xy (0.5)
(1)
800 = ε x (0.5) + ε y (0.5) + γ xy ( −0.5)
(2)
γ xy = −450 μ
Subtract Eq. (2) from Eq. (1):
Equation (1) yields
350 = 200 + 0.5ε y − 225 ,
ε y = 750 μ
(a)
γ
2
(μ)
ε'
(400, 225)
ε'=
x
ε3
O
ε2
2θ p "
10
R = 1752 + 2252 = 285 μ
ε1
C
R
400 + 750
= 575 μ
2
ε(μ)
y
1
225
= 26.1o
2
175
= 2r = 570 μ ,
θ s " = 18.9o
θ p " = tan −1
γ max
ε 1 = 575 + 285 = 860 μ
ε 2 = 575 − 285 = 290 μ
Continued on next slide
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13
(400 + 750) = −575 μ
1−1 3
(γ max ) a = 860 + 575 = 1435 μ
(b) ε 3 = ε z = −
575 μ
570 μ
18.9o
575 μ
x
x’
Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or
instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other
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Copyright Act without the permission of the copyright owner is unlawful.
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