Finite element computer program to analyze cracked orthotropic sheets

A two dimensional orthotropic sheet with through-the-thickness cracks and temperature gradient was analyzed. The program includes special crack tip elements that account for singular stress fields associated with crack opening and crack sliding displacements at the crack tip. The program also includes a linear spring element and a constant strain, triangular element. A number of problems for which closed form solutions exist were analyzed to demonstrate the capabilities of the program.