The idea that the diagonal shear failure of reinforced concrete beams without or with stirrups exhibits a strong non-statistical size effect has been generally accepted in the fracture research community since the 1980's and during the last few years is…
The idea that the diagonal shear failure of reinforced concrete beams without or with stirrups exhibits a strong non-statistical size effect has been generally accepted in the fracture research community since the 1980's and during the last few years is gaining ground among design engineers as new evidence from properly scaled tests of large beams is emerging. Several competing theories to explain this size effect have been advanced. After mentioning the problems with some theories, the paper reviews the energetic theory of size effect and its recent application to the classical truss model (or strut-and-tie model). The formulae previously derived by energy analysis of the fracturing truss model are compared with numerous test data avail- able in the literature~ and a good agreement is demonstrated.