Chip seal construction process

Johan Gerber, Zutari (Pty) Ltd

Abstract and Videos

The video, Chip Seal Construction Process, summarizes the construction process of a triple seal in South Africa. A triple seal has three layers of aggregate; 20mm + 7mm + 7mm; and three spray coats of binder, typically but not restricted to; S-R1 + S-E1 + Cat65%. The second video, Abaqus 3D Chip Seal Model, is a digital copy of the chip seal construction process. The chip seal model was developed in Abaqus, has a load consisting of a 20 kN truck wheel inflated to 800 kPa, rolling at 10 km/h. Stress and strain results were obtained at the aggregate-binder interface as an approach to quantify the environment conducive for ravelling.

Chip Seal Construction Process:

Abaqus 3D Chip Seal Model:

Final Thoughts

Why do this?
Observe behavior that is difficult to measure in the field.
Use this approach to refine aspects of chip seal design.
Inexpensive method to compare Chip Seal designs.