Mode-I Stress-Intensity Factors for a Cracked Slab Under an Arbitrary Thermal Shock

A stress intensity factor solution for a cracked slab subjected to an arbitrary thermal shock on one surface has been derived. As a first step, the transient temperature distribution was calculated for an arbitrary surface loading through the use of Duhamul’s integral relationship and the unit response for a slab that is insulated on the other face. The arbitrary nature of the transient surface loading was accommodated by a versatile polynomial containing both integral- and half-order terms. Once the resulting transient stress states were determined via elasticity theory, the resulting stress intensification for an arbitrary crack was approximated using a weight-function approach. The procedure was checked with known stress intensity solutions for an edge-cracked plate subjected to a linear down shock followed by a constant temperature soak. Excellent agreement was observed for this test case for a variety of crack lengths.