Why does the modified Arrhenius' law fail to describe the hydration modeling of recycled aggregate?

Why does the modified Arrhenius' law fail to describe the hydration modeling of recycled aggregate?

Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Thermochimica Acta - Volume 626, 20 February 2016, Pages 13-30

Jena Jeong, Hamidréza Ramézani, Nordine Leklou,