A new finite-element program has been developed in order to analyze the stress-intensity factor K and J-integral for surface cracked plates and shells. The program is composed of the flat shell elements and the line spring elements which are based upon the line spring model proposed by Rice. Summary of results analyzed by this program is as follows:

1. In the analysis of K for surface-cracked rectangular plates, the results have been in good agreement with the three-dimensional finite-element results obtained by Raju and Newman. The computing time is one order less than the three-dimensional finite-element analysis. 2. Nearly the same results as those by Parks have been obtained in the analysis of the J-integral for surface-cracked rectangular plates. 3. As a practical application of this program, K and J have been analyzed for surface-cracked part-circular cylindrical shells. The effect of curvature has been found to lower the values of K and J slightly. Therefore, estimates of K and J by those of flat plates for the equivalent crack configuration give conservative results.