Regulate and Overlay

Regulate and Overlay is a road rehabilitation method involving two primary stages:

Regulation – Modifying the existing road surface by milling high areas or filling low spots to correct surface irregularities, restore proper drainage, and achieve a uniform profile.
Overlay – Placing a new layer of asphalt (wearing and/or binder course) over the regulated surface to improve structural integrity, ride quality, and durability.

This treatment is recommended under the following conditions:

Existing pavement shows surface irregularities, minor rutting, or uneven settlement.
Drainage issues exist due to poor crossfall or slope.
The structural condition of the pavement is still sound (i.e., base/sub-base is intact), but surface distress warrants improvement.
To extend pavement life without full-depth reconstruction.

Methodology and process involved in Regulate and Overlay procedure

1. Site Assessment

Conduct a thorough assessment of the existing pavement to identify areas that require regulation. This includes inspecting for surface irregularities, distress, and drainage issues. Document the findings and determine the extent of regulation needed.

Use levels and surveying tools to measure crossfalls and determine required regulation depths.

2. Site Preparation

Clear the area of vegetation, debris, and loose materials.
Ensure proper temporary traffic control and site demarcation.
Grade the subgrade/sub-base where exposed, ensuring positive drainage.

3. Regulate

Milling high spots using a cold planer as per JKR standard milling depth (usually 50 mm or based on site needs).
Filling low areas using approved regulating material (e.g., asphaltic concrete or dense graded base) to match the desired profile.
Leveling and compacting using a grader and roller to ensure uniformity and density.

4. Overlay

Apply a prime coat (bitumen-based) at a rate of 0.5–1.0 L/m², adjusted according to ambient temperature (JKR guidelines: 25–45°C).
Ensure full curing before placing any overlay.