Contracting - Cape Seal

CONTRACTING: CAPE SEAL

What is Cape Seal?

Cape Seal uses the advantages of two a sealing and rehabilitation methods combined. It is the application of a chip seal followed within a few days by a slurry or microsurfacing.

What is it used for?

Cape Seals are used where a chip seal is too rough and requires a smooth finish, for example in residential streets. In instances where cracking is a problem a polymer or asphalt rubber modified chip seal can alleviate cracking and the slurry provide the smooth and hard wearing surface.

Are there different types?

Cape Seals may vary from treatments to protect a pavement and provide a long lasting seal, to treatments for heavy duty pavements, to crack treatments.

Using a chip seal as a base provides a thick asphalt membrane that is impermeable and durable. The durability of any asphaltic material depends on how thick the membrane is. A typical seal will have a membrane over 1mm thick and up to 3mm. An asphalt mixture has typically only 8 microns. The addition of a slurry capping not only makes the surface smooth but locks the aggregate of the chip seal in place eliminating stone loss.

The base must be sound for a conventional cape seal and if large cracks are present then crack sealing should be used (>10mm). Potholes should always be filled. For alligator cracks or smaller cracks a polymer modified chip seal might be required. Asphalt Rubber modified chip seals especially are effective. Pavements can have life extensions of upwards of 10 years.

How is Cape Seal Coating done?

After preparation of the surface a chip seal is applied using standard application methods. A special cape seal design is carried out to ensure the right combined amount of binder is used.

The chip seal uses the correct binder to tackle the distress in the pavement.

After seal curing of between 48 hours and a week the slurry layer is placed and allowed to cure.

The finished work is a smooth and hard wearing surface.

What does it do?

Cape Seal lasts longer, can treat cracks, is smoother than a chip seal, more durable than a slurry and will last as long as a hot mix overlay at a lower price.

What does it cost?

Conventional Cape Seal is less expensive than asphalt hot mix overlay and will last as long. When applied to cracked surfaces, modified cape seals are more expensive than a conventional one inch overlay but will extend pavement life often by 10 years or more, compared to failure in 1-2 years.

Specifications

For Contracting Products and Services contact pavements@slurry.com