Fig. 11.

Evaluation of the elasticity limit for one individual sample under compression: the number of damaged elements is defined as the sum of all elements with $(D>0)$ divided by the total number of elements in the structure. A piece-wise quadratic function is fitted to the initial part of the curve. The obtained elasticity limit (blue triangle) is usually lower than the 0.2% yield point (green rectangle). At the 0.2% yield point, already a sizeable amount of damage is present (see small images)