Pass counts, asphalt temperature windows, padfoot vs smooth drums, compaction force in kN and Tier 4 regen habits — explained by Hamm application engineers.
Vibration drives vertical energy into the mat or lift; oscillation uses horizontal shear that densifies thin lifts without hammering bridge decks or nearby structures. Many Hamm tandem classes let operators switch modes from the cab when the paving plan moves from thick binder to thin wearing course.
For a common 60 mm wearing course inside a healthy temperature window, a 10–13 t tandem often reaches target density in roughly five to seven passes. Mix design, wind and ambient temperature change the window — application engineers can sketch a rolling pattern for your corridor.
Padfoot drums suit cohesive soils with higher plasticity where kneading action matters. Smooth drums suit granular fills and asphalt mats. If plasticity index sits near the boundary, we often stage both shells so the crew can swap when lift conditions change after rain.
Conventional hot-mix usually wants breakdown rolling while the mat is still hot enough to move, then finish rolling before the mix cools below the project's finish temperature. Warm-mix designs shift the window lower. Cab temperature aids and pass maps help crews stop guessing when wind picks up.
Published centrifugal force and static line load describe the energy available at a given amplitude and frequency. Your QC plan should call out the class and amplitude setting, then verify with density tests or EVIB trends rather than chasing a single marketing number.
Intelligent compaction packages can record pass counts and stiffness indicators for export into contractor quality reports. Availability varies by class — ask for the mapping option when you request a highway tandem quote.