Size effect on structural strength is normally understood as the effect of the characteristic structure size on the nominal strength of the structure when geometrically similar structures are compared. Fracture test are usually conducted on relatively small specimen and them this information is extrapolated to large structures. The question is that are we able to reproduce the size effect in the modern numerical techniques. Numerical calculations by computational code based on finite element have been done. The results show that in order to produce a size effect, it is necessary to use a regularization method.