EnviRoad’s Ambient Mix Asphalt Technology – The Ex Situ Aggregate Base Stabilization Process

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EnviRoad’s Ambient Mix Asphalt (AMA) is an emerging green technology comprising of several cold-mix processes. All of the AMA processes utilize Earthbind® products. Presently, the AMA technology includes, but not limited to the:

  • Ex Situ Aggregate Base Stabilization process
  • Alternative Paving process
  • Stabilized Full Depth Reclamation process, and
  • Cold In-Place Recycling process.

This overview is the first part of upcoming blogs that will feature all four of the AMA processes in more detail. This particular blog will focus on the Ex Situ Aggregate/soil Base Stabilization Process.

The Ex Situ Aggregate/Soil Base Stabilization (AMA) Process

It is well known that the performance of a paved and unpaved road is significantly impacted by the stability of the base and/or underlying soils. Consequently, natural in situ soils may not provide the support that is needed to achieve acceptable performance under traffic loading and environmental conditions. When such conditions exist, it can be important to stabilize the sub-grade, sub-base, and or the road base.

Normally, chemical base stabilization processes entail mixing a stabilizer into a base material, in-place, using a motorgrader or milling machine. The AMA process instead is an ex-situ construction process where excavated existing or virgin road material is thoroughly mixed in a pugmill with a pre-determined amount of Earthbind® solution. The advantages of using a pugmill vs. a milling machine or motorgrader is that the material is more thoroughly mixed and coated therefore increasing the efficacy of the particle to product contact and bonding.

The AMA blended material from the pugmill is then transported to the project site and constructed into a new base using a paving machine. This AMA mixing process is typically done in close geographical proximity to the project location…close enough where the Earthbind treated material remains fresh. The AMA methods for native soil/aggregates is a base stabilization method and not considered paving.

EnviRoad’s Earthbind® Stabilizer product is used in the ambient mix process. Earthbind® Stabilizer is specifically engineered to be an effect, environmentally friendly soil stabilizer. The benefits of stabilization of sub-grade, sub-base, and road base with Earthbind® Stabilizer include:

  • Improves the strength and durability of the soils/aggregate;
  • Adds water-resistance/waterproofs the treated material;
  • Reduces dusting and conserves fines and aggregate material;
  • Decreases the “erosivity” of the road material;
  • Upgrades marginal material that are typically undesirable for the sub-grade or for road base construction;
  • Greatly reduces maintenance activities and maintenance costs
  • Helps reduce/eliminate wash-boarding;
  • Helps minimize potholes (in combination with adequate drainage);
  • Provides temporary or permanent (with maintenance) wearing surfaces on unpaved low-volume roads.
  • Can reduce pavement thickness requirements on road bases that will be paved.
  • A significant increase in cohesion.
  • Acquiring flexural strength due to the visco-elastic properties of Earthbind®.
  • Improved moisture resistance and durability.

The benefits of using the AMA process with Earthbind® Stabilizer will definitely help maximize the long-term performance of your road. For more information on how Earthbind® Stabilizer can work for your project, please contact an EnviRoad sales engineer at 1-800-536-2650.