Determination of Rutting and Water Susceptibility of Selected Pavement Materials using MMLS3

Abstract

Accelerated pavement testing (APT) has become an increasingly important research tool to evaluate and validate pavement materials. Model APT devices, such as MMLS3, which can be used in situ and in the laboratory, have been used very successfully for this purpose recently. This paper describes the results of testing 48 cores from different Swiss pavement structures (hot and cold thin surfacings, porous asphalt, gussasphalt and stone mastic asphalt SMA) using the MMLS3 load simulator. The research was conducted at Stellenbosch University where the MMLS3 test set-up has been modified to provide the ability for accelerated pavement tests on cylindrical asphalt specimens. Furthermore, the test set-up enables the study of the susceptibility to water damage of an asphalt structure. The aim of the investigation presented in this paper, was the comparison of dry and wet asphalt pavement materials in order to determine their susceptibility to rutting.
First results clearly indicate that the influence of water may reduce the performance of asphalt structures. In one case an increase of rutting up to 50% compared to dry testing was found.