Flexible pavement with SMA as an anti-fatigue layer

Josipa Domitrovic, Luka Krišto, Tatjana Rukavina

Last modified: 2022-06-08


"Asphalt Pavement Alliance has defined the perpetual pavement as ˝an asphalt pavement designed and built to last longer than 50 years without requiring major structural rehabilitation or reconstruction and needing only periodic surface renewal…˝. The perpetual pavement design approach assumes that one can design against certain types of failure or distress by choosing the right materials and layer thicknesses. This can be achieved by providing enough stiffness in the upper pavement layers to preclude rutting and enough total pavement thickness and flexibility in the lowest layer to avoid fatigue cracking from the bottom of the pavement structure. One way to reduce the bottom up fatigue cracking in pavement structure is to add an additional anti-fatigue layer to standard asphalt layers. This layer can be an extra layer that increases the total asphalt layers thickness, or it can be layer separated from the standard asphalt base layer by reducing its thickness.
The presented research aimed to evaluate the suitability of application, Croatia traditionally used asphalt mixtures within the concept of perpetual pavements. Among traditional asphalt mixtures, the stone mastic asphalt was selected as a mixture for the anti-fatigue layer. The analysis was carried out for proposed perpetual pavements of different thicknesses and/or position of stone mastic asphalt anti-fatigue layer. Calculation of pavement layers stresses and strains was done in CIRCLY software, taking into account the seasonal variations in asphalt layers properties.
The analyses have shown that the addition of stone mastic asphalt layer as an anti-fatigue layer can extend flexible pavement design life."


flexible pavement; perpetual pavement; anti-fatigue layer; stone mastic asphalt