Two more important observations were made by studies \citep{Firmo2015,Benzarti2011,leone2009effect}. First, increasing the exposure temperature shifts the stain distribution into a linear form, particularly for low and moderate load level, due to the dropping in the epoxy stiffness that smooths the stress/strain distribution \citep{Firmo2015}. Second, it is detected that raising the temperature can also increase the effective bond length (least length required to transfer tensile stress from the concrete substrate to FRP strips/sheet by direct shear)  more than the minimum length recommended by some design guidelines \citep{Leone2009,Benzarti2011,Kabir2016,Firmo2015}