MOUNT AIRY, NC—In-ground parking garages in Dallas, TX experience the same thing: erosion of the soil beneath them, and silt infiltration that overwhelms and clogs the drainage system, thus causing more and worse erosion. The keys are catching it early enough, and choosing the right solution to keep it from happening again.
The three-story, in-ground parking garage at McKinney Ave. and Worthington St., the main thoroughfare of the Dallas’ “Uptown” area and home to some of the poshest apartments, business addresses, shopping, hotels, restaurants and bars, had silt and water infiltration, so the owners called in Edens Structural Solutions, Bixby, OK, with 30 years experience of structural lifting and repair. David Edens, company president, says they studied the problem and decided on geotechnical polyurethane foam. “Our solution was to use void-filling TerraThane geotech foam. It’s simple to apply, expands and cures in place, and is an excellent water and air barrier,” says Edens.
They drilled a shaft down along the piers and soldier piles and lagging, to survey the problem and found the water had gone through the block wall and carved out what appeared to be a five-foot cavity. Soldier piles and lagging is an earth retention technique that retains soil using vertical steel H-shaped piles usually spaced between three and ten feet apart with horizontal timber sheeting called lagging.
“We chose NCFI’s TerraThane foam, but we first had to do some geometry to figure out how much to use. We didn’t quite know the full size of the cavity, even after using a boroscope and ground-penetrating radar, but we knew it ran at a right angle, so we used the Pythagorean Theorum to find the length of the hypotenuse and that told us the size. We ran a 3/8 vinyl tube behind the block and dropped in the TerraThane polyurethane foam.”
Edens explains, “TerraThane gives us four products in one. It fills It fills in large and small voids running both vertical and horizontal in the cavity, serves as water and air barrier so it will impede future water and silt infiltration, it’s amazingly strong, and it’s light, so it won’t add any weight to the block wall. It was ideal for this project. We were in and out in two months without minimal disruption of the parking. The alternative would have been to shut the entire structure down for a year-and-a-half as they removed the entire block wall, dug out the lagging, installing 26 gauge panels, then backfilled the cavity with gravel. That might have cost upwards of $2 million or more, plus loss of parking revenue. TerraThane saved this one and the owners have asked us back for more work.”
Edens says his company has been using NCFI products for years. “We also use their concrete lifting foam, and their trench-breaker foam. We trust the products and we trust the company. We like that they’re a US company with over 40 years experience, so they know their products and they know how to apply them. They are one of the only major companies out there to send their engineers and tech people to our job sites. We’re doing a big job in Austin, and they sent two guys down to make sure they sold us the right product and to make sure the application process we chose was ‘best practice’. That little extra makes a huge difference to my bottom line.”
For more information or to arrange an interview on this subject contact Dale McGlothlin, (202) 341-8615
NCFI, headquartered in Mt. Airy, NC since 1964, manufactures polyurethane foam chemical systems for spray foam-in-place insulation (SPF), geotechnical, roofing, marine floatation, packaging, specialty molding, and many other uses. The company also offers a complete line of flexible foams for furniture seating, transportation seating, bedding, carpet underlay, and packaging. NCFI also has manufacturing plants in Hickory, N.C., Dalton, GA., and Salt Lake City, UT. To learn more about NCFI please visit www.NCFI.com.