Compaction of Noise-Reducing Asphalt Mixes in the Laboratory

This paper investigates the impact of compaction methods on the performance of quiet (porous) asphalt mixes. Four different compaction methods are included: Marshall impact compaction, Hveem kneading compaction, Superpave gyratory compaction, and rolling wheel compaction. The rolling wheel compaction was selected as a surrogate for field compaction. Specimens of four different porous mixes with the nominal maximum aggregate size (NMAS) varying from 4.75 mm to 19 mm were compacted by the four methods, and were tested for various performance indices, including permeability, sound absorption, friction, surface macrotexture, moisture sensitivity, resistance to raveling and aging, and rutting resistance. It is found that difference exists among performances of a porous asphalt mixture compacted by different methods. The compaction effect varies with aggregate gradation and the performance being evaluated. Recommendations are given in the paper on selection of compaction methods based on the nominal maximum aggregate size.