Strategies to construct durable longitudinal joints in asphalt pavements: laboratory and field investigations

The primary objective of this research study is to identify the most effective strategy for constructing longitudinal joints in asphalt pavements. Laboratory experimental design includes density measurements and cracking susceptibility using an Indirect tensile strength test. Statistical analysis using Fischer's least significant difference method was employed to rank the construction strategies based on their performance. The results indicated that the restrained edge technique always provided higher densities and cracking resistance. High tack coat application (0.64 lit/m2) and Void Reducer strategies were determined to be superior to all other construction techniques. These results were also validated using the field core samples, wherein high tack coat application on the longitudinal joint and the hot pinch methods were recommended to be used together to improve the density and the cracking resistance. The proprietary Void Reducer product was also determined to enhance the density and lower the likelihood of cracking in in-situ conditions.