Investigation of crack resistance potential of stress absorbing membrane interlayers (SAMIs) under traffic loading

This study has investigated the crack resistance potential of selected SAMIs subjected to wheel loading. Tests were carried out in a wheel tracking facility and temperature-controlled environment to simulate field stress and strain conditions. The results indicate that the potential of SAMIs to retard crack growth depends on factors such as the SAMI stiffness and thickness, the overlay thickness, the load level and temperature. It was found that the relative benefit of SAMIs was higher when lower SAMI and overlay thicknesses were used. The study also showed the SAMIs to be effective at 20 °C and 30 °C but relatively ineffective at 10 °C.