THE SIZE EFFECT EXPRESSION FOR AN ELASTIC-SOFTENING MATERIAL

Earlier work has led to the derivation of a size effect expression which relates the maximum sustainable load for an elastic-softening material, such as concrete, to a solid's dimensions, provided these are large. The derivation depends on assumptions made with regard to the behaviour of the elastically equivalent softening zone size and the fracture energy, as the maximum load state is approached. The present paper provides underpinning for the size effect expression as it applies to a positive geometry, and also as it applies to a negative geometry when the expression gives the load required for a softening zone to be fully developed.