ABSTRACT
Abstract The existence of cracks appears to significantly modify the transfer properties of con crete structures. The cracks can result from mechanical or thermal loading, due to the response to service loads, but they can also simply result from shrinkage, even if no external loading is applied. When concrete is cracked, the nature of the percolating fluid becomes a parameter of secondary importance if compared to the crack pattern. Experimental results showing the big influence of cracking and classical tools for mo delling are presented in this chapter and some conclusions for structural design are drawn.
