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• Dynamic response of asphalt mixture was monitored in SGC test by SmartRock sensors. • Understanding of compaction characteristics between PAC, SMA and AC mixtures. • Effect of nominal maximum aggregate size on compaction of mixture is investigated. Compaction degree is an essential parameter to characterize the construction quality and performance of asphalt pavement. Under the same compaction conditions, asphalt mixtures with different aggregate sizes and gradation may exhibit different compaction characteristics. Accordingly, this paper aims to study the compaction characteristics of asphalt mixture at the meso -scale through particle response of the mixture by using SmartRock sensor. Firstly, a laboratory test scheme of the asphalt mixture is designed and the SmartRock sensors are used to obtain the internal stress of the mixture during compaction. By comparing the particle stress with the height of the specimen, it is inferred that the stress state of the particles can reflect the compactness of the compacted material, and the change rate of compaction degree in logarithmic coordinates is proposed to characterize the compaction performance of the asphalt mixture. Furthermore, the quantitative analysis is comprehensively conducted related to the different nominal maximum aggregate size (NMAS), locations and gradation types. The results reveal that the asphalt mixture with larger NMAS has a better compactibility in terms of forming a stable skeleton structure, and the mixture in the middle of specimen can be compacted more easily than that in the top and bottom area of specimen. It can be aslo found that the gradation type affects the compaction performance through the probability of coarse aggregates interlocking with each other. The open-graded mixture (i.e, PAC-16) is relatively faster to achieve the target compaction degree than gap-graded and dense-graded mixtures (i.e, SMA-16 and AC-16, respectively). Although the asphalt mixture with larger NMAS and coarser gradation can reach a certain compaction degree with a rapid speed, it doesn't mean the mixture can achieve higher compaction degree finally under the action of subsequent compaction work. The test result shows that the asphalt mixture with coarser aggreages is relatively difficult to compact with lower final compactness. The experimental research sheds substantial light on the internal relationships between the response of the particles and compaction charateristics of asphalt mixture at meso -scale. [ABSTRACT FROM AUTHOR]

• Dynamic response of pavement and vibrating drum were monitored by SR and HCF sensors. • High frequency signals were used to analyze the dynamic response in vibrating compaction. • Linear relation was established between acceleration of vibrating drum and compactness. • Understanding of compaction mechanism in terms of acceleration and stress for particles. Although compaction is one of the most critical steps during the construction of asphalt pavements, effective real-time technologies to detect the compactness of the asphalt mixture non-destructively are still rare. Currently, most methodologies in practice are experience-based, and few studies have provided insight into the particle interaction characteristics and quantitative response during the vibration compaction of asphalt pavements. Accordingly, both field and laboratory tests are conducted in this study to investigate the response of an asphalt mixture quantitatively under a vibrating compaction load at the meso-scale. First, a field test program is designed, and sensors (e.g., SmartRock and acceleration sensors) are used to measure the dynamic response of an asphalt pavement and the vibrating drum during vibrating compaction. The quantitative analysis reveals that the first three rolling impacts exert a significant and dominant compact effect on the asphalt mixture. Subsequently, a linear relationship between the acceleration of the vibrating drum and the vertical stress in the asphalt pavement is demonstrated. Furthermore, the SmartRock sensor is also employed in the laboratory test to detect the internal dynamic response under gyratory compaction, and the relationship between the compaction degree and the vertical stress in the asphalt mixture is established. Finally, three assessment methods for asphalt mixture compactness are proposed as characterization of the compactness by the acceleration of a vibrating drum, intermediate variables such as the stress of the mixture under a gyratory compaction, or acceleration and stress of the pavement. Comparison of the results illustrates that the dynamic response inside the mixture during the compaction can directly reflect the compaction degree of the asphalt mixture, and the compaction degree and the peak acceleration of the vibrating drum exhibit a strong linear correlation during the vibration rolling process. [ABSTRACT FROM AUTHOR]