< Back Lake Jonathan Flats Five-story apartment complex next to a highway Year Completed: 2018 This five-story apartment complex constructed on Lake Jonathan Flats in Chaska (MN) required a design that reduced the lateral soil load against the east side of the building’s 20-foot-tall pre-cast-concrete foundation wall. The north side underground parking garage is under extra stress because 270 feet away is highway 41, which runs parallel to the building and which is 45 feet above the building’s grade. Engineers designed for a total depth of 14 feet of TDA (Tire Derived Aggregate) to be backfilled against the 12-inch-thick wall. TDA reduces the lateral load and helps control drainage and moisture running from Highway 41 to the nearby lake. Additional benefits of TDA include the following: Reduced Lateral Load: 1/2 the lateral load of soil, which can reduce retaining wall costs. Lightweight: 1/3 weight of soils (600 spare pounds per loose volume cubic yard). Interlocking: Creates a foundation for overlying structures. Permeability: Up to 50% better drainage than gravel. Project Gallery Previous Next

< Back Lexington Avenue (Shoreview, MN) Six inches of rain doesn't derail 5-day construction Year Completed: 2004 The public works department at Ramsey County, MN promised the city of Shoreview, a suburb of St. Paul, that a repair of 300-feet of Lexington Ave. wouldn’t take more than five days last summer. The road has roughly 8,000 vehicles each day accessing adjacent businesses and neighborhoods. Five days would be a long time for some of the impacted people. Jerry Auge, the general supervisor of maintenance and construction for the county, didn’t anticipate the extra challenge of a six-inch rain during construction. But because the county chose TDA (Tire Derived Aggregate) to use as lightweight fill, the water wasn’t as big of a hassle. “The rain slowed us up a little, but with the tires, the water didn’t affect us that much,” Auge said. “We pumped the area dry. We didn’t have to dry out the tires.” Other types of fill have been used on different county projects. On this job, when TDA was compared to alternatives, like dirt, wood chips, or styro foam blocks, TDA came out ahead. TDA is lightweight, cost effective and less labor intensive than some of the alternatives. Auge had worked with TDA on another county project and knew the lightweight factor was important for the Lexington Avenue job. The problem on Lexington was the road had settled between 2.5 to 3 feet. When the road was built roughly 10 years earlier, conflicts with utilities stopped the county from dealing with the boggy soil under the road. The road began to sink within two years of construction. Now, when the county wanted to fix the road, utilities were still an issue. The solution was to excavate two feet of dirt off the top of the roadbed and replace it with three feet, or 1,500 cubic yards, of TDA and build the road back up. “Had we used dirt, chances are the road would have settled again because of the weight added to the top,” Auge said. “With lightweight fill, we’re able to keep the weight off.” …and keep 8,000 vehicles moving every day. Project Gallery Previous Next

< Back Purgatory Creek Recreation Area Stable foundation for recreational area Year Completed: 2002 This existing land (which is now Purgatory Creek Recreation Area) was made up of soft, muddy soil at a low-lying grade next to a small lake. Engineers needed to cost-effectively design a stable foundation that could be built on without the risk of the overlying structures sinking into the soil below. A lift of TDA (Tire Derived Aggregate) placed directly on the existing grade created a strong foundation that eliminated the risk of differential settlement or other failures of the park features. The irregular shape of the individual tires pieces created an internal reinforcement; a "snowshoe effect" that spread throughout the site and prevented individual areas from sinking. The high permeability and thermal insulation properties of TDA help create a capillary break, so moisture can't wick its way towards the surface. In addition, TDA has about 8 times better thermal insulation than soil, which helps prevent frost activity. "With conventional embankment construction, there was a high risk of embankment failure," said Bill Cody Principal Engineer for American Engineering Testing, Inc.. "To achieve the grades the city wanted and reduce the risk of failing the new embankment, lightweight fill materials were a top consideration." Project Gallery Previous Next

< Back Parking Lot Retaining Wall (New Hope, MN) Reducing lateral load on lower lot retaining wall Year Completed: 2000 This project involved building a safe, stable retaining wall in between two parking lots that are side by side, but have an approximate 20 foot elevation difference. This retaining wall isn't holding back a gradual slope; it is instead supporting what is more of a cliff-like embankment that the higher parking lot is situated on. To reduce the lateral load pressing against the retaining wall, TDA was installed. With 592 cubic yards of volume to fill, if this wall had been backfilled with dirt, the total weight of the placed fill would've been 1,518,480 lbs when dry, and 1,998,000 lbs when wet (2,565 lbs/cy and 3,375 lbs/cy, respectively).TDA weighs approximately 600 lbs/cy, making the total weight of the TDA fill for this project 355,200 lbs. This weight cannot be compromised, as shredded tires do not absorb water, and they are relatively free-draining. Project Gallery Previous Next

(Back) Projects: Landfill Landfill Burnsville, MN 2006 Berm fill, new cell liner. Read More Landfill Mora, MN 2003 Gas collection, new cell base, 2 new roads and leachate collection. Read More Landfill Sioux Falls, SD 2010 New cell base and gas collection. Read More County Landfill Lyon County, MN 2003 New cell lining. Read More Crow Wing Landfill Brainerd, MN 2002 & 2005 Landfill used TDA for a Leachate Liner and water dispersion. Read More Veolia Landfill Eau Claire, WI 2009 ? Read More

< Back Previous Next < Back American Engineering Testing (St. Paul, MN) Saving limited valuable real estate space Year Completed: 2018 Stearns Bank N.A. Equipment Finance Division in Albany needed to add parking lot space for employees and visitors. The new space, however, is more than just a place to park vehicles. Underneath the layers of asphalt and Class 5 gravel, around 95,000 shredded and compacted scrap car tires, or tire-derived aggregate (TDA), serve as a filter and drainage system for storm water runoff. “When you add more parking, you add more flat surfaces and you have more water to deal with,” said Shawn Robinson, superintendent with Miller Architects & Builders. Storm water ponds are constructed to mitigate and filter excess water runoff. Holding ponds, however, often require space that could be used by business and home owners for other purposes. “Open water ponds are a mosquito breeding ground,” said Curt Hoffman, TDA specialist with TDA Manufacturing. “They can also be dangerous to kids. Kids like to climb fences.” Miller Architects & Builders out of St. Cloud designed and oversaw the project, while TDA Manufacturing, a division of First State Tire based in Isanti, provided the TDA. Craig Bardson Excavating Inc. of Albany supplied the gravel and did the compacting, while Knife River did the paving. All the water will come off the parking lot and flow into the drainage system underneath. “Not only does the TDA slow water down and deal with the capacity, it treats it, as well,” Robinson said. Hoffman agreed. “The carbon in the rubber and the steel banding in the tires attracts phosphorus, nitrates and other contaminants,” he said. Also, TDA is less expensive than traditional aggregate and it lasts longer. “The TDA provides a capillary break,” he said. “It can withstand freeze-thaw cycles and you don’t have to worry about fissures or cracking.” First State Tire shreds about 2.5 million tires a year, creating 65,000-75,000 cubic yards of aggregate that is applied to various projects, including storm water management, roadway bedding, embankment support, trails, parking lots and other purposes. “TDA has been around for a long time, we’ve been producing it for 30 years,” Hoffman said. “It’s starting to gain popularity through education and workshops. If it’s done right, tires can be environmentally friendly.” As millions of tires are produced and discarded each year, a portion of them will be reused for other purposes, such as aggregate, which in turn preserves resources. It is one step closer to a greener future.

< Back Infrastructure Improvement Project (Waconia, MN) Under-street sewer and water in area with excessive moisture and sloping terrain Year Completed: 2015 Putting a sanitary sewer and water main network under a street in an area of town fraught with excessive moisture and sloping terrain was the challenge for the city of Waconia, MN. The solution came in using Tire Derived Aggregate (TDA) as a lightweight fill. The project is in a basin. Soil boring tests showed fill, swamp deposits and very loose clay-like sand extending as far as 21-½ feet below the surface. The geotechnical recommendations called for a lightweight aggregate backfill to reduce loading on the utility pipes that were designed to float within the fill embankment. TDA was selected based on its track record of working in soils that aren’t stable enough to support a project. TDA also reduces loading and pressure against adjoining structures, like retaining walls or pipes. It's also approximately one-third to one-half the weight of soils, free draining and has high shear strength. Approximately 650 cubic yards of TDA were installed around the pipes. The material will improve sub-base drainage and bring stability to an area that would otherwise not be able to host an underground utility network without concern of damaging the pipes. The light weight of the TDA will reduce vertical and horizontal pressures, and the thermal insulating properties will help prevent pipes from freezing. The second challenge on the project was to construct a stable road on top of the trench. This is where TDA really shines , according to Monte Niemi, CEO of First State Tire Recycling. "More than 100 roads in Minnesota have successfully been built on top of TDA,“ Niemi said. “The dual responsibilities in the Waconia project showcase the unique, cost-effective benefits of R.-T.E.A.” When asked why R-T.E.A. was chosen for this project, Bolton and Menk engineer Jake Saulsbury said, “Tire-derived aggregate is lower costing than other aggregate products, is more durable, and easier to install than Styrofoam.” Saulsbury said that Bolton & Menk will be using TDA again in future projects. Project Gallery Previous Next

SLOPE STABILIZATION Road landslides typically occur due to the loss of stability in a slope caused by weak backfill and/or excessive loading from the combination of heavy, saturated soils within the materials that make up the slope. ​ A slope is considered stable when the shear strength of the soil is greater by a factor of safety than the driving force (weight of the backfill) downslope along the projected minimum slip plane. In the case where the driving force exceeds the shear strength of the backfill material, the slope will fail and slide downward. Because TDA is lightweight and permeable, it is effective in reducing excessive loading on an unstable slope. An added benefit, TDA's high permeability permits drainage through the various layers and can dramatically reduce the potential hydrostatic pressures that promote slope stability. In landslide repair projects, TDA is typically designed using alternating layers of TDA and soil. There are several key advantages to designing a slope with a TDA backfill: ​ It is less than half the weight of soil, so the driving force causing a potential landslide is significantly reduced. The internal shear strength of TDA is greater than soil, further increasing the resistance to the overlying driving force. Using a TDA backfill design results in a more stable slope as compared to a soil backfill design. Designs using TDA as an alternative backfill can achieve the needed factor of safety values with much less excavation and engineered backfill. SEE PROJECTS

< Back Stearns Bank (Albany, MN) Parking lot water flow problem solved Year Completed: 2019 Previous Next < Back Project Name This is placeholder text. To connect this element to content from your collection, select the element and click Connect to Data. Heading 6 Project Gallery

LANDFILL USES Designing engineered systems for use in a landfill using TDA is similar to designing systems using traditional materials like rock or gravel. The only difference is adjusting the designs to accommodate the difference in the engineering properties of TDA: density, shear strength, compressibility, specification (Type A or Type B), and hydraulic conductivity. TDA is lighter and more permeable than gravel and rock, and has a higher bulk density (so less TDA is needed to occupy the same volume as rock or gravel). It also produces less dust (compared to gravel). ​ Although the methods are similar, care should be taken when placing TDA. Steel wire protruding from TDA has punctured rubber tires on loaders and other machinery. When spreading TDA, track-mounted equipment should be used including dozers, loaders, or blade-equipped steel wheel compactors (see installation ). ​​ ​ Examples of TDA use in landfill include: ​ Drainage layer in a leachate collection system : TDA is incorporated as a component of the leachate collection system to provide drainage, limit freezing on overlying clay barriers in cold climates and protect the liner system from damage during construction and operation. When excavating trenches for the leach field, the TDA serves as a media for the treatment of wastewater, so the material should be free of any contamination or debris that might interfere with treatment or negatively impact the surrounding soil or groundwater. A separation barrier is generally used in leach field construction between the aggregate media and the soil backfill. The barrier prevents the migration of fines into the aggregate, which could reduce the hydraulic conductivity of the media and result in plugging of the system. Treated paper is often used as the barrier for conventional rock aggregate systems; since the protruding wires in TDA could rip this paper, geotextile fabric is a good alternative. ​ Leachate recirculation trenches: TDA can be used as backfill around leachate recirculation trenches, typically replacing conventional materials such as granular soil. Leachate recirculation trenches are used to reintroduce collected leachate back into waste. Rock aggregate (natural or crushed gravel) is the traditional medium used for septic system leach fields. However, the practice of gravel mining from rivers is increasingly limited due to environmental degradation associated with the practice. Environmental controls on rock quarries have increased the operational costs of these facilities, and in some cases, they have ceased operation. The net result is that rock aggregate has become expensive and difficult to obtain in many locations. TDA has numerous benefits that make it an excellent alternative to rock aggregate for drainage applications. TDA has higher permeability than traditional drain rock aggregate and a substantially lower unit weight. TDA has a higher surface area per unit volume, which increases the area for biofilm development and subsequent biological treatment of the drainage water. Rather than causing potential environmental problems by mining or producing rock aggregate, producing TDA reuses a waste product and keeps used tires out of landfills. Because of these benefits, TDA may perform better than rock aggregate and in many locations may be less expensive to use. ​ Gas collection trenches: TDA used in this application replaces granular soil as the bedding material for gas extraction pipes in the collection trenches. These trenches are usually located beyond the footprint of the landfill to control the lateral migration of landfill gas. ​ Gas collection layer: TDA layers provide good drainage and help protect clay and geomembrane liners in landfill gas collection systems. ​ Drainage layers in landfill covers: TDA can be used as a drainage layer in landfill covers. In this application, the TDA is typically enclosed in geotextile to decrease the number of fines in the TDA layer and maintain TDA’s high permeability. ​ SEE PROJECTS

< Back Central Community Rain Garden School districts choses TDA for storm water management system next to parking lot Year Completed: 2005 Previous Next < Back Project Name This is placeholder text. To connect this element to content from your collection, select the element and click Connect to Data. Heading 6 Project Gallery