Comments on “Is the cause of size effect on structural strength fractal or energetic-statistical?” by Bažant & Yavari [Engng Fract Mech 2005;72:1–31]

Aim of this letter to the Editor is at replying to the criticisms raised by Bažant and Yavari [Bažant ZP, Yavari A. Is the cause of size effect on structural strength fractal or energetic – statistical? Engng Fract Mech 2005;72:1–31] against the fractal approach to the size-scale effects on the mechanical properties of materials and the concept of the Multi-Fractal Scaling Law presented by Carpinteri [Carpinteri A. Scaling laws and renormalization groups for strength and toughness of disordered materials. Int J Solids Struct 1994;31:291–302]. These criticisms will be analysed thoroughly, showing how they also contain some mistakes and misunderstandings. The presented elucidations should redirect the discussion to a more correct scientific debate.