Full Depth Reclamation of Roadways

Olympic View Drive, Phase I and Phase II Rehabilitation

The City of Lynnwood desired to reduce the time it would take to re-construct the pavement section along Olympic View Drive from 180th to 168th (Phase I) and 180th to 76th Avenue West (Phase II).

The existing roadway consisted of an HMA trafficking course of varying thickness over gravel base situated on fill or native moisture sensitive subgrade. Locally, portions of the roadway surface had been overlaid several times by additional layers of HMA. In addition, depending upon location, road grade was raised as much as 12 inches. Taking all this into consideration, the owner and construction management team determined that the project was an ideal candidate for full depth reclamation.

Full depth reclamation (FDR) is a process whereby in-place HMA and gravel base materials are recycled by pulverization, graded to the appropriate sub base elevation (which may locally require adding and mixing in additional gravel base to raise grade), addition of a stabilizing agent (Portland cement), moisture conditioning, mixing and compaction. Because this method utilizes an "assembly line" procedure as opposed to the traditional method of building a road section one layer at a time, considerable time savings was realized. Time savings combined with sustainable construction procedures that eliminate pavement removal by recycling in-place produced substantial project cost savings.