Laboratory Evaluation of a Vertical Vibration Testing Method for an SMA-13 Mixture

Abstract

In order to simulate the on-site compaction conditions of a Stone Matrix Asphalt (SMA) mixture, The Vertical Vibration Testing Method (VVTM), Superpave Gyratory Compactor (SGC), and Marshall method are used to test the SMA-13 mixture, and the physical and mechanical properties of the asphalt mixture designed by these three methods are tested. Subsequently, the influences of the molding method on the mechanical properties are compared. The influence of vibration compaction time on the volume parameters of the SMA mixture is studied. Following the heavy traffic compaction standards, the vibration compaction time of the SMA mixture is determined. The results show that the densities of the heavy Marshall specimen, VVTM specimen, and SGC specimen are 1.018 times, 1.019 times, and 1.015 times greater than that of the standard Marshall specimen, respectively. The passing rate of the 4.75 mm aggregate of the standard Marshall specimen is 29.9%, and that of the VVTM specimen and SGC specimen is 31.1% and 30.5%, respectively, while that of the heavy Marshall specimen is 34.5%. The mechanical strength of the specimen can be greatly improved as the density increases. On the other hand, by the same compaction work, the mechanical strength of the VVTM specimens can be increased by at least 7% compared with the heavy Marshall specimen. The mechanical strength of the VVTM specimen is increased by at least 22% compared with the standard Marshall specimen. The results also show that under the optimal asphalt-aggregate ratio and the same compaction work, the compressive strength and shear strength of the VVTM specimens are increased by at least 6% and 9%, respectively, compared with the Marshall specimens. In summary, the performance of the asphalt mixture designed by the VVTM is superior, providing a wider choice for future asphalt mixture design.

Investigation on cement-improved phyllite based on the vertical vibration compaction method

“…The pores in the specimen become smaller, forming a compact overall structure, and the friction and intercalation between the phyllite particles are correspondingly larger. Therefore, the strength of the phyllite formed by VVCM is greater than that of the sample formed by the heavy compaction method [ 34 ].…”

“…During the rolling operation of the vibratory roller, the eccentric block is driven by the vibrating shaft to rotate rapidly, forming the interference force of the vibration system of the “roller-compressed material.”. Under the action of the interference force, the vibrating wheel vibrates with a frequency equal to that of the interference force [ 31 – 34 ]. The vibration is further transferred to the material to be pressed, making the material gradually denser.…”

“…The heavy compaction method currently used for compaction quality control does not match the rolling characteristics of on-site tools, and the heavy compaction method does not match the vibration compaction mechanism of the on-site roller. To address this problem, a VVCM that is more in line with the actual situation is introduced herein [31][32][33][34].…”

“…vibrates with a frequency equal to that of the interference force [31][32][33][34]. The vibration is further transferred to the material to be pressed, making the material gradually denser.…”

“…The vibration is further transferred to the material to be pressed, making the material gradually denser. In order to ensure the consistency of the indoor compaction effect and the on-site rolling effect and based on the working principle of the directional vibration roller, the vertical vibration testing equipment (VVTE) was used, as shown in Fig 1. Based on the existing research results [31][32][33][34], the parameters listed in Table 3 were used in the experiments.…”