Numerical Simulation of GTM Asphalt Mixture Design Parameters Based on Discrete Element

摘要

The laboratory compaction method produces a huge effect on the design of mix proportion and performance testing of asphalt mixes. For the result of a performance test to yield reliable physical properties, it is necessary to ensure that laboratory specimens are fabricated in a manner that adequately simulates field compaction. However, the laboratory compaction based on Gyratory Testing Machine (GTM) is closed to field compaction. This study simulated the compacting process of asphalt mixes based on GTM, and analyzed the displacement, stress and strain to changes in mold in order to reveal the physical properties during compacting by using discrete element theory. The results indicated that the design method based on GTM is reasonable and adaptability, and the basic requirements that GSI must be less than or equal to 1.0, and GSF must be great than or equal to 1.0 is scientific. What is more, the study presents the reasonable value range of design parameters to GSI and GSF for engineering application, which is referred to in the study as GSI can be less than or equal to 1.05, and GSF can be great than or equal to 1.3.