Trr No. 1171 Asphalt Materials And Mixtures, pp. 178-183
The purpose of this study was to determine which laboratory compaction procedure best reproduces the pore size distribution of rolled bituminous sand mix surface courses in the field. Mercury intrusion porosimetry tests were performed on laboratory-compacted samples and field cores to determine their pore size distributions. Comparison of fabric was accomplished by using curve descriptors constructed on differential and cumulative pore size distribution curves. Two gradations, two asphalt types, and four aggregate combinations were evaluated. Laboratory compaction was accomplished by varying the parameters of four laboratory compactors and by compacting at three mix temperatures. Analysis of the results of all compaction methods indicated that the gyratory compactor with a vertical ram pressure of ZO psi and 35 revolutions with a 1-degree gyratory angle plus 5 revolutions of leveling pressure (no applied gyratory angle) best reproduces the fabric produced by the rolling procedures presently used in the field.