I. Rolling Speed Control

General Principle: Slow first, then fast; low speed and uniform speed.

1. Subgrade (soil, sand & gravel)Speed: 2–4 km/hFast rolling is strictly prohibited to avoid surface compaction and internal looseness.

2. Cement-stabilized baseSpeed: 2–3 km/hExcessively high speed easily causes peeling, looseness and poor flatness.

3. Asphalt pavement

• Initial rolling: 1.5–2 km/h

• Secondary rolling: 2–3 km/h

• Final rolling: 3–4 km/hMust be slow at high temperatures to prevent asphalt displacement and cracking.

II. Rolling Passes Control

General Principle: Light first, then heavy; edge first, then middle; overlapping rolling.

1. Subgrade compaction

• Static rolling: 1–2 passes

• Vibratory rolling: 3–5 passesContinue until the compaction degree meets the standard with no obvious wheel marks.

2. Cement-stabilized base

• Static rolling: 1–2 passes

• Vibratory rolling: 3–4 passesTotal passes: generally 4–6 passes.

3. Asphalt pavement

• Initial rolling: 1–2 passes (stabilization)

• Secondary rolling: 3–4 passes (densification)

• Final rolling: 1–2 passes (removing wheel marks)Total passes: generally 5–7 passes.

III. Key Rolling Points

• Keep uniform speed; do not brake, turn or stop halfway.

• Overlap width: 1/3–1/2 of the wheel width.

• Roll the road edge first, then the middle to prevent material displacement.