Tandem vibratory rollers are used primarily to compact paving materials, such as asphalt mixes and roller-compacted concrete. These machines have two steel drums that vibrate via an internal, eccentric mechanism, which often can be adjusted to vary the frequency and amplitude of the vibratory action. Some tandem vibratory rollers, equipped with satellite-navigation and proprietary software systems, continually report the degree of compaction and can map the jobsite’s compaction values for future reference.
