Livingston Street Reconstruction with Tire Shreds
Tewksbury, MA
The Town of Tewksbury, Massachusetts has reconstructed an 800-foot length of Livingston Street using about 200,000 shredded scrap tires as lightweight fill - the first application of its kind in Massachusetts, and one of a handful of similar projects nationally.
Stephens Associates Consulting Engineers (SA) was retained by the civil engineer, at the request of the Town of Tewksbury, to provide a value-engineered design for the first-ever use of tire shreds as lightweight fill in a roadway embankment in Massachusetts. The Town has experienced problems with Livingston Street for more than 40 years. The roadway traverses a wetland underlain by organic silt and peat. It was reconstructed in the late 1970’s, but the Town has applied 7 to 8 overlays to various portions of this section since then. Significant portions of the existing roadway embankment are petroleum-contaminated. SA recommended the use of tire shreds as lightweight roadway embankment fill and provided environmental guidance in addressing the petroleum contamination. SA designed the tire-shred-fill embankment. The Roadway reconstruction was funded under Massachusetts Highway Department (MassDOT) Chapter 90. The Town received approval from MassDOT to use those funds with this unique solution. The Contractor’s bid for the total reconstruction was about $500,000. The savings to the Town by using the tire shreds as lightweight fill are estimated to be more than $220,000. The construction provided for the beneficial use of about 200,000 scrap tires.
Why Lightweight Fill?
This section of roadway has been plagued for decades by poor performance caused by soft soils in the embankment and underlying foundation. The soft soils caused pavement cracking and deterioration due to settlement, requiring continuous maintenance and repairs. The roadway has settled up to 3 feet in some spots since the last reconstruction 24 years ago. The lightweight fill is designed to lighten and strengthen the embankment, substantially reducing settlement and improving long-term performance.
Why Tire Shreds?
Scrap tires present a significant waste problem for Massachusetts and the US. Americans discard about 280 million tires annually. About 25 percent go unused, being landfilled, stockpiled or illegally dumped. The stockpiles and illegal dumps look ugly, breed mosquitoes and rodents, and pose fire hazards. Disposing of tires and shreds legally in landfills unnecessarily wastes large volumes of valuable space. Tire shreds have beneficial properties that make them excellent lightweight fill. Tire shreds also appear to be the most cost-effective lightweight fill available.
Objectives
The Town of Tewksbury’s objectives for the reconstruction of Livingston Street were:
- A Smoother roadway surface;
- Enhanced long-term roadway performance;
- Reduced long-term roadway maintenance; and
- Reduced short-term construction costs.
Results
In addition to reducing and reusing a significant portion of the solid waste stream, the project has thus far fulfilled the objectives of the Town. Reconstruction was accomplished well under budget. Cost savings were about 33 percent, when compared to the estimated cost of the next viable lightweight fill alternative.