OPTIMAL-DESIGN OF QUASI-BRITTLE ELASTIC BODIES WITH CRACKS

The problem of optimal design for quasi-brittle elastic bodies with cr acks is considered in cases of static and cyclic loading. Optimization problems considered consist of finding the boundary of a body such th at the optimized functional (volume of the body) attains an extremal v alue, while satisfying prescribed bounds on stress intensity factors a nd minimum number of cycles (structural durability). Such problems are characterized by incomplete information concerning crack size, locati on, and orientation. In this context, the paper presents some possible formulations of optimal structural design problems based on minimax ( guaranteed) approaches. Using these approaches, optimal designs are ob tained for beams and plates with surface and internal cracks.