Research on Gyratory Compaction Characteristics of Low Void Modified Asphalt Concrete Materials

Abstract

AbstractThe compaction characteristics of asphalt concrete materials have a decisive impact on the degree of field compaction. Therefore, the study of the compacting law of composite modified asphalt mixture has important guiding significance for the field construction of pavement. This study used a gyratory compactor (SGC) to analyze the compaction characteristics of composite modified asphalt concrete materials from the two dimensions of asphalt-aggregate ratio and gradation. The test added 10% PE modifier by mass of asphalt and 0.2% polymer fiber. The compaction characteristics of LA-10 (low-void asphalt concrete materials), SMA-10, and AC-10 gradations under asphalt-aggregate ratio of 7.5%, 8.0%, and 8.5% were studied and compared with the compaction situation of the commonly used EA-10 for steel bridge deck pavement. The results showed that with changes in the asphalt-aggregate ratio, the trend of the mixture voidage and compaction curve was consistent. The LA-10 mixture reached the target voidage range at an asphalt-aggregate ratio of 7.5%, with good workability, while the AC-10 and SMA-10 mixtures reached the target voidage range at an asphalt-aggregate ratio of 8.0%, and were easier to compact. The compaction density energy index was SMA-10 > AC-10 > LA-10 > EA-10, and the compaction ease of LA-10 was relatively close to that of epoxy asphalt mixture EA-10. According to the above compaction characteristics, LA-10 is suitable for the lower layer of pavement, and SMA-10 and AC-10 are suitable for the upper layer of pavement.