Dynapac has launched a new series of tandem asphalt rollers equipped with "Oscillation" compaction technology. In traditional vibratory rollers, the drum uses an eccentric weight to create vertical "up-and-down" impacts. While effective for deep compaction, this vertical force transmits waves through the ground, which can crack adjacent building foundations, rupture underground pipes, or disturb sensitive equipment in hospitals and laboratories.
The Dynapac Oscillation system uses a dual-eccentric shaft design. The two shafts rotate in opposite directions, cancelling out the vertical forces. Instead, they generate a purely horizontal "back-and-forth" torque on the drum. This horizontal force creates a shearing action between the asphalt particles, rearranging them into a dense matrix without the "bouncing" effect of vertical vibration.
From an engineering perspective, the key benefit is the "Resonance-Free" operation. Vertical vibrations can cause the roller drum to bounce at specific frequencies, leading to uneven compaction marks on the pavement surface. The oscillation drum stays in constant contact with the road, providing a smooth, mat-finishing action. Additionally, the system is equipped with "Soft-Start" logic. When the operator engages the vibration, the eccentric shafts ramp up to full speed gradually. This eliminates the shock load on the drum bearings and the asphalt mat, preventing the "crazing" (hairline cracks) often seen at the start of a rolling pass. This technology allows construction crews to work at night in sensitive urban zones without noise complaints or structural damage risks.
