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Hot In-Place Recycling

"Hot in-place recycling (HIR) has proven to be a viable technique for rehabilitation of pavements at low cost by using existing in place materials." - FHWA SA-98-042

Quick, Cost-Effective and Environmentally Friendly

The Hot in-place Recycling (HIR) process involves heating and scarifying the existing pavement to a depth of ¾ to 1½ inches, and treating the scarified material with an asphalt rejuvenator. There are a couple of different methods for the HIR process. In one, the train of equipment scarifies and recycles the old pavement, then lays the recycled mix and a virgin hot mix wearing surface. This special equipment has two screeds—the first screed lays the recycled mix as a leveling course, and virgin hot mix is fed through the second screed for the surface course. This one-pass process moves quickly with minimal traffic delay. In another process, the recycled mix is re-laid with a paver and compacted. This may be left as is, or resurfaced later with a new hot mix.

The asphalt rejuvenator may be emulsified, cutback or a soft asphalt cement, and it may have rejuvenator oils, polymers or other additives; or it may be unmodified asphalt. During the mixing of the scarified material with the rejuvenator, additional aggregate or other additives may also be blended in to correct the gradation or improve the mix.

Martin Asphalt Products for HIR

Martin Asphalt Product	Description
AES-300	High float, anionic asphalt emulsion
AES-300RP	High float, anionic asphalt emulsion with rejuvenating oil.
MS-2, MS-1	Anionic medium setting asphalt emulsions.
CSS-1	Cationic slow setting asphalt emulsion.
ETR-1	Cationic emulsified rejuvenator oil.
ARA-1	Anionic emulsified rejuvenator oil.
SCM-1, SCM-2	High performing cutback cold mix asphalts.
CM-300	Non-emulsion solventless cold mix asphalt .

Benefits of Hot In-Place Recycling

Aged, distressed pavements are replaced with recycled asphalt mix.
In-place recycling reuses the existing aggregate and asphalt, reducing new raw material and hauling costs.
Cracks are filled.
Deformations such as potholes, ruts, bumps and shoved pavement are removed.
Clearances under bridges and curb height can be restored.
With the proper choice of materials, aged asphalt can be rejuvenated, and poor aggregate gradations can be corrected with added aggregate material.
In-place recycling minimizes the time a lane is closed for re-construction.
There is excellent public acceptance of recycled materials.
The recycled pavement can, itself, be recycled when its time has come.

Where to Use HIR

Hot in-place recycling is the ideal solution for severely distressed pavement surfaces with cracking, shoving, ruts, and/or oxidation. The pavements need to have a structurally sound base as this process does not correct base failures. The pavements should be sufficiently thick to support the equipment. The existing pavement should be analyzed and the recycled mix designed in a laboratory. It is important to understand the reason for the pavement surface distresses, and correct any deficiencies that may pose problems for the recycled pavement.

Martin Asphalt Makes It Easy

Through Martin Asphalt, you get Everything Asphalt—a full range of products for constructing, maintaining, recycling and rehabilitating your pavements. In addition, you receive technical assistance in selecting the right materials and application. The company's AASHTO Certified Laboratory makes sure the products meet your specifications. And your products are delivered both on spec and on time via Martin’s Gulf Coast network of production plants, storage facilities and transportation fleet including ocean-going and inland barges, rail cars and tanker trucks. Contact us for more information on products for your stabilization projects.