Cracking Resistance and Fracture Behavior of Modified Asphalt Mixtures

Abstract

Cracking is a physical failure-finite in size—that occurs due to repeated loading by traffic, both traffic and environmental factors. In this study, the fracture and cracking resistance of glass fiber reinforced (SBS) polymer modified mixtures is analyzed. Four formulations were designed: Conventional Asphalt with and without GF (CA, CA-GF) and SBS modified asphalt with and without GF (SBS, SBS-GF). The performances under loading were evaluated on the basis of Marshall properties, ITS and SCB tests. Marshall stability of the modified SBS was 26% higher than that for those with GF, and the others were also improved by adding GF to CA mixture up to 22% and SBS mixture by 12.5%. The increase in ITS of SBS-modified asphalt reached to 93.4 % due to the addition of GF and up to about 23.5% using CA mixture and up to about 10% for SBS blend. The combination of SBS+GF showed the higher cracking tolerance (CT index = 239.755), this means that, both modified by SBS and reinforced by GF increased in CT Index with 71.7% and 18.8%, and when combined between CA/SBS's mixtures also represented an increase in CT index equal to 37%. indicating that ductility and fracture resistance were improved. The SCB test has also displayed improvement in Gf with (164.4%) when SBS modified asphalt, and densification by (22.5%) for CA and (30.1%) for SBS have been approximately achieved due to the fibrer glass additions. F Unsurprisingly, these findings indicate that incorporating SBS and GF together could effectively enhance asphalt pavement during service as well as its crack resistance, particularly at high stress and variable temperatures.