Study on the effects of Stone Mastic Asphalt on the ability to resist rutting and cracking on asphalt concrete pavement in Vietnamese conditions

1. The thesis has analyzed the scientific basis of the formation of stone-on-stone contact, the role of coarse aggregate skeleton to increase resistance to irreversible deformation, the role of binder and fiber additives asphalt concrete.
2. The thesis analyzed, evaluated and selected the Marshall method to design the SMA mixture with the Nominal Maximum Aggregate Size of 12.5mm. Proposing material requirements, technical specifications of SMA12.5mm in Vietnam.
3. The thesis has conducted experiments to evaluate the superiority of the mixture of SMA mixture compared to the hot mix asphalt through mechanical criteria such as: Internal Friction Coefficient (tgφ), Cohesion (C); Plasticity Coefficient (m); Viscous Strain Activation Energy (U); Moisture Resistance; Static Modulus; Dynamic Modulus; Flexural Strength; Rutting Resistance; Shear Resistance and Cracking Resistance (CTIndex).
4. The thesis has conducted experiments to compare some technical criteria of SMA mixtures and asphalt concrete applying the hot and warm mixing techniques. Using Sasobit additive reduces 30°C when mixing and compacting to save energy, reduce environmental impacts and increase the transport and construction time of the asphalt concrete layers.
5. The thesis has proposed pavement structure using SMA and proved this is a good solution to reduce thickness, enhance the rutting and cracking resistance of the surface layer for road with large traffic volume.
6. The results of the laboratory tests show that the material SMA12.5 mixtures meets the technical requirements of the road construction materials according to the current Vietnamese standards, while ensuring the rutting and cracking resistance. Therefore, it is qualified as a surface layer for expressway in Vietnamese conditions.