Contracting - Crack Sealing

CONTRACTING: CRACK SEALING

What is a Crack Sealing?

A When pavements fail they fail often by cracking. This can be caused by aging and embrittlement, low temperature effects, fatigue, or movements in the base caused by shrinkage or exiting cracks below the pavement surface. In many situations the best way to seal the surface again is by filling the cracks with an elastomeric asphaltic compound. Generally cracks that are 7-15mm are candidates for crack filling. Fatigue cracks are usually an intense pattern and more suited to overall treatments like asphalt rubber chip seals or Cape Seals.

What is it used for?

Crack Sealing is used as a preparation treatment before another type of surfacing , for example slurry , hot mix overlay or asphalt rubber seal.

Are there different types?

Crack sealants may be cold or hot pour. Cold crack sealants are emulsion based and usually latex modified. They are suitable for smaller cracks that are not very active. Such as age cracks. Hot pour crack fillers are generally crumb rubber or SBS modified at high concentrations ( 25% and 12% respectively).
These materials are highly elastomeric and stretch and recover with the movement of the crack.

How is Crack Sealing done?

The cracks are routed to remove debris and any weak material.
The cracks are cleaned with compressed air.
Crack sealer is poured or injected into the crack with a spray device.
The surface is finished with a shoe leveler or similar device on the spray wand.
The surface may be sanded , especially in the case of an emulsion crack filler. Unwashed sand or grit is suitable.

Emulsion crackfillers must be fully cured before overlaying. Cracksealing should not be overdone and a stage will be reached where there are too many cracks to fill and a different treatment should be considered.

What does it do?

Crack Sealing seals cracks preventing water getting into the pavement. Applied at the right time crack sealing will prevent or delay pothole formation. It should ideally be used with some sort of final overlay. Because cracks are a function of stress relaxation in the pavement, i.e. they can open up in places other than the filled areas. In instances where this is happening an overall membrane treatment is indicated.

What does it cost?

Crack sealing is the least expensive method of road maintenance. A VSS estimator will be pleased to estimate your job.

Specifications

For Contracting Products and Services contact pavements@slurry.com