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Ecodur 201: Asphalt Coating (After Many Years)


Asphalt in its naturally occurring tar­like form, has had various uses over the past two thousand years, mostly as a type of adhesive or water­proofing mixture. However, by the 1830s in the UK and 1870s in the US, it was starting to be used as a paving material.

Today, by far the largest use of asphalt/bitumen is for making asphalt concrete for road surfaces which accounts for about 85% of the asphalt used in the United States. It is almost entirely a petroleum derived product and the road surface mixes are typically composed of 5% asphalt/bitumen cement and 95% aggregates that are stone, sand, and gravel.

Being a petroleum based product, it contains locked in chemicals that under high temperature and exposure to ultraviolet rays, off gas and the asphalt eventually cracks allowing water to get in which can freeze in winter, further hastening road surface deterioration to the point where, under heavy traffic loads, it starts failing altogether with the aggregate breaking off.

Nearly four years ago in Higley, Arizona, a concrete construction company’s main asphalt entrance was showing signs of the surface failing due to heavy traffic and effects of high doses of UV. Rather than have the entire surface ripped up and repaved, it needed an alternative solution that would cause less disruption and cost.

Ecodur in its original formulation has over 20 years of testing on asphalt road surfaces with original test strips still in existence showing how it not only stands up to vehicular traffic but also how it retains its bond integrity with asphalt. Being free of Volatile Organic Compounds (VOCs), and completely waterproof and non­toxic, it does not expose applicators to the kinds of risks normally associated with many conventional epoxy coatings.

Ecodur also has exceptional adhesion and, most importantly, retains a significant degree of flexibility for its entire life and can be readily repaired as it re­bonds to original coatings at the molecular level. This ability to ‘give’ under load is a standout feature as most conventional epoxy coatings rapidly micro­crack when stressed allowing moisture to creep into substrates that can become a major source of damage during freezing periods.

Application Results
After nearly four years, the Ecodur treated asphalt surface shows no measurable wear and full integrity with the asphalt below has been totally maintained. This is directly in line with previous long term testing on asphalt in Canada. The original application had caused no disruption to vehicular traffic and was performed quickly.

With rapid curing and final inspection and release of the site within 24 hours, the job was completed more quickly than had a conventional epoxy coating been used. All indications are that the treated areas will remain maintenance free far longer than that anticipated for untreated asphalt areas.