ESEM FBG FOS FTIR History of engineering & technology RAP gradation air voids alkali-activated materials artificial neural network asphalt asphalt content asphalt pavement binder–aggregate adhesion cohesion complex modulus coring drainage effective binder content falling weight deflectometer falling weight deflectometer (FWD) fatigue cracking fiber Bragg grating (FBG) sensors fiber optics sensors (FOS) flow number hot mix asphalt hot mix asphalt dynamic modulus hot-mix asphalt ignition test interface bonding laser Doppler vibrometer (LDV)