PSI - Issue 2_A

M. Nourazar et al. / Procedia Structural Integrity 2 (2016) 2415–2423 Author name / Structural Integrity Procedia 00 (2016) 000–000

2418

4

∫ ∫ +∞ −∞ +∞ −∞

− + ) y h h α

y

(

1 α

α

e

− α α α α α α − ) ) 2 1 e e

(

)

α

2

2

− e d i x λ

z

2

= w x y b ( , )

+ λ λ πδ ) i

y h

( ( )

0

,

λ

< <

2

(

π

2 1

(9)

− + ) y h h α

y

(

1 α

1 α

e

(

)

α

2

− e d i x λ

z

2

= w x y b ( , )

+ λ λ πδ ) i

− ∞ < < y

( ( )

0,

λ

2

(

π

2 1

2

2 2 2

2

2 2 2

where ( ) λ δ is the Dirac delta function and . It is elementary to show that Eqs. (9) satisfy the first condition (5). The associated stress components by virtue of Eqs. (1) and (9), are given by: ) λ α , ( f = − + + 1 α ζ ζ ) λ α ( f = − − + 2 ζ ζ α

∫ ∫ +∞ −∞ +∞ −∞

y

) α α h

y

+ − (

y

1 α

α

2

ζ

b e

e

− e e d i x λ ) 2

(

− α α α α α α − ) ) 2 1 h

0 µ

α

2 1

x z

2

( , ) x y

y h

0

,

< <

λ

=

σ

zx

2

(

π

2 1

(10)

y

y

+ − (

) α α

y

1 α

1 α

2

ζ

b e

e

− e e d i x λ )

(

0 µ

α

2 1

x z

2

( , ) x y

− ∞ < < y

0,

λ

=

σ

zx

2

(

π

2 1

+∞

y

2

ζ

i

b e

1 2 1 α α α + − ( y

h

y

)

α

0 µ

e

e

(

)

2 1 α α

2

∫ ∫

y z

i x e d λ −

( , ) x y

y h

0

,

=

< <

σ

λ

zy

2

2 1 λ α α − (

)

π

−∞ +∞

(11)

y

2

ζ

i

b e

1 2 1 α α α + − ( y

h

y

)

1 α

0 µ

e

e

(

)

2 1 α α

y z

i x e d λ −

( , ) x y

y − ∞ < <

0

=

σ

λ

zy

2

2 1 λ α α − (

)

π

−∞

The integrals in (10) and (11) can be evaluated with the contour integration. For the sake of brevity, the details of manipulation are not given here. The final results are

∞ ∫

1 ∫ ∞ −

y

2

ζ

2

2

z b e

0 µ ζ x

u

u

1

1

r

) f u

) R f u ζ α

(

(

ζ α

( , ) x y

r

e

du R −

e

du

(

)

=

σ

zx

2

u

u

2 ( ) f π α

1 2

1 ∫ ∞

1 ∫ ∞

y

ζ

2

b e

0 µ ζ

u

u

1

1

r

) f u

) R f u ζ α

(

(

ζ α

x z

e

du

e

du

(

)

+

2

2

2 ( ) f π α

u

u

y

ζ

b e

( K r f ζ α

( K R f ζ α

0 µ ζ

)

)

x z

1

1

y

( 2 ) y h

(

)

+

− −

r

R

4

π

1 ∫ ∞

1 ∫ ∞

y

2

ζ

2

2

e b x ζ

0 µ

yu u

( 2 ) y h u u −

1

1

r f

u

R f

u

(

) ζ α

(

) ζ α

x

z

e

du

e

du

(

)

+

2

2

4

π

x

x

3 2

3 2

( r u

( R u

)

)

2

2

r

R

y

ζ

( x b e k r f ζ α z

µ ζ

( k R f ζ α

)

)

y

0

1

1

( , ) x y

(

),

σ

=

(12)

zy

r

R

2

π

2

2 2 α

2

2

2 2 2

where 1 (.) k is the modified Bessel function of the second kind and . From Eqs. (12), it is obvious that stress components are Cauchy singular at dislocation position which is a well known feature of stress fields due to Volterra dislocation. f y r x α = + , ( 2 ) y h − f R x = +

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