Assessment of the influence of compaction method on asphalt concrete resistance to moisture damage

Research work in the area of asphalt concrete stripping reflects general agreement among researches that existing adhesion theories do not completely describe the stripping phenomenon. The stripping mechanisms fail to specify the source of water necessary for stripping to start and progress with time. Locating the water source and route to the pavement interior is of great significance to effort seeking a preventive measure against stripping. This paper reports on the investigation of the influence of various construction variables focusing on compaction-induced cracks, referred to as checking, on pavement resistance to stripping. A new compaction technique was used to produce a crack-free asphalt concrete surface which offered a much higher resistance to stripping compared with conventionally compacted surfaces. Other factors associated with construction, which can influence the stripping susceptibility of compacted asphalt concrete pavements, were also considered. Cores recovered from field-compacted pavements were used throughout the investigation. The results of the experimental investigation indicated that construction has a significant influence on the compacted mix resistance to stripping. The study also identified surface water as the water source and construction cracks as the route for surface water to the pores inside the mix. Vacuum saturation, used as part of the moisture conditioning procedure, has in the past obscured the influence of construction-induced cracks on stripping susceptibility