Stephens Associates Consulting Engineers, LLC Receives ACEC/MA Engineering Excellence Award
Tewksbury reconstructs Livingston Street using recycled tires
Scrap tires present a significant waste problem for Massachusetts and the US. Americans discard more than 280 million tires annually. About 45 percent are landfilled, stockpiled or illegally dumped. These stockpiles look ugly, breed mosquitoes and rodents, and pose a fire hazard. Current reuse options include retreading, tire-derived fuel, feedstocks for manufactured products, and civil engineering applications.
Livingston Street has been plagued for decades by high maintenance and poor performance caused by soft soils. Tire shreds have excellent engineering properties that make them effective as a lightweight fill, including moderate strength, low unit weight, durability, and high permeability. In 1999 the Massachusetts Department of Environmental Protection issued the first Beneficial Use Determination to J.P. Routhier & Sons, Inc. of Littleton, for use of this innovative material as lightweight fill in civil engineering applications.
Cuoco & Cormier Engineering Associates, Inc. of Nashua, New Hampshire provided civil engineering on the project. Stephens Associates Consulting Engineers, LLC (SA) designed the tire shred embankment. SA worked closely with Professor Dana N. Humphrey, Ph.D., P.E., of the University of Maine to design the excavation and replacement of site soils to maximize lightweight fill. The Town, in cooperation with the Massachusetts Highway Department (MassHighway), has retained Stephens Associates to study the effect of the tire shreds in mitigating roadway settlement. The research is being jointly funded by the MassHighway and the Federal Highway Administration (FHWA). Stephens Associates will prepare a comprehensive research report, including standard specifications and design details to be used by MassHighway on future projects (See MassHighway Press Release, Amorello Announces Recycled Material Study, November 28, 2001).
To date the Project has been very successful. Construction cost estimates showed the tire shreds to be highly cost effective. Actual construction was accomplished well under budget. Cost savings were about $220,000, or about 33 percent, when compared to the next viable alternative. Despite being slowed by the presences and relocation of some unforeseen utilities, the Project and Stephens Associates have exceeded the Town’s expectations. The Town saved a significant percentage on construction costs while beneficially using a typical waste.
TRC Environmental provided consultation on contaminated soil found at the site. The Town engaged J.J. Phelan & Son, Inc. to reconstruct the Roadway. Tire shreds are supplied by J.P. Routhier & Sons, Inc.