Study on compaction characteristics and mechanical performance deterioration of large stone porous asphalt mixes

Abstract

Large stone porous asphalt mixes (LSPM) have advantages in promoting pavement performance, including cracking resistance, rutting resistance, and moisture susceptibility. Engineering practice demonstrates that performance degradation is crucial and has an impact on the durability and service life of asphalt pavement. Therefore, this paper aims at investigating the damage characteristics of LSPM as well as proposing the corresponding control methods. Firstly, a simulation device is designed to carry out the temperature cooling testing of LSPM in the laboratory. Then, the variation of air void contents in LSPM was analyzed with different testing temperatures, loading times, and freeze–thaw cycles. LSPM macro-mechanical strengths and cracking resistance were measured during freeze–thaw cycles. The outcome demonstrates that different sections cool at various rates and for varying lengths of time. The effective compaction time and compactness are directly related to the ambient temperature. Paving at medium and high temperatures is an efficient way to increase the compactness of LSPM. The testing temperature, loading time, and freeze–thaw cycles have significant influences on the change of air void contents, while the influence of load strength is low. The penetration shear strength decreases as the number of freeze–thaw cycles increases, and the change trend gradually decreases. Freeze-thaw cycles will lessen the anti-cracking performance of LSPM. Strictly regulating construction parameters, air void content, and drainage conditions could increase the LSPM asphalt pavement's durability and service life. The change in pore structure composition is the primary factor influencing the damage performance of LSPM.