ABSTRACT
ABSTRACT: The definition of roughness characteristic of rupture crack surface (RCCS) is introduced. The results of RCCS investigation of different strength concretes on the special experimental installation are stated. The RCCS differences of normal and high strength concretes are displayed. On the RCCS basis the criterion of existence of interlock (CEI) of roughness on the crack sides is introduced. The model of resistance to shear in crack is worked out.
