Vibration of unreinforced pavement concrete

The interim report for this research project indicated that a substantial amount of vibration is transmitted to pavement concrete by the mesh and mesh depressors. When plain (unreinforced) pavements were specified, concern arose over the possibility of insufficient consolidation. The Department thus instructed contractors to install three additional spud vibrators on their finishing machines. To check consolidation on a contract with plain pavement, cores were extracted at known distances from any spud vibrator. Density and entrapped air measurements on these cores agree with the findings of the earlier report. Adequate consolidation was achieved without the mesh and depressors, and no segregation of aggregate nor increase in entrapped air was found. Further, the additional three vibrators in a 24-ft width specified by the Department are not considered necessary.