2.3 Consider an infinite periodic array of equally spaced cracks along the x-axis in an infinite plate subjected to equal uniform stresses σ along the x- and y-axes at infinity (Fig. 2.14). Verify that the Westergaard function is sin(πZr/λ), where Z is the complex variable, r is the distance from the crack, and λ is the crack spacing.
Fig. 2.14: An infinite periodic array of equally spaced cracks in an infinite plate subjected to equal uniform stresses at infinity.
Then show that the stress intensity factor is given by KI = σ√(πa), where a is the crack length.