Jay Sprague of the South Carolina-based Denver Down Research Facility took on a private client’s pullout anchor testing questions with erosion and sediment control systems and components. The results began to yield revealing data on anchor pullout performance, and in a way that has not been previously explored.
Following up on the work, Sprague has begun exploring a wider application of the testing approach utilized in this project, with an eye to how this could benefit the field more broadly. It may, as he noted in his conversation with Geosynthetica’s GeoTalk Podcast, lead to a new standard one way—with more input from the field’s erosion and sediment control system providers.
GeoTalk is published on Tuesdays. Previous episodes:
- June 6: Craig Benson on Sedimentation, Dams, and Watershed Health
- June 13: Robert Bowers on Geosynthetics in Segmental Concrete Pavements
- June 20: The Geotechnical Poetry of Mary Nodine
- June 27: Leap Frog Ideas for Low Impact Development
- July 5: Effective Education for Erosion and Sediment Control System Adoption
PULLOUT ANCHOR TESTING IN EROSION & SEDIMENT CONTROL
At DDRF, which is a research site owned and operated by TRI Environmental, Sprague provides large-scale, standardized testing services, such as rain and stormwater-induced erosion testing on slopes, flume testing for channel integrity, sediment retention device performance testing, and much more.
The pullout anchor testing was motivated by the simple question: How well do anchors designed for rolled erosion control products actually work?
“Their idea was to create a proprietary anchor that could replace your standard commodity products–six-inch staples, washer pins, rebar j-hooks, etc., etc.–by applying a little science and design to the structure of the anchor itself,” says Sprague.
TRI, working with the client, designed a soil-filled box testing apparatus with an attached pulley system. The pulley could be attached to an anchor on one end and an applied load on the other. A load cell was set between them to record anchor pullout strengths. The team tested with multiple soil types and compaction rates, tested different embedding depths, utilized different materials,
“[The data] developed an elegant demonstration of anchor performance that had really not been put out to industry before,” Sprague says.
What does he see this testing approach to bring to the erosion and sediment control field?
“I believe the applications to benefit most are encouraging industry to innovate in an area that has been relegated to nothing more than commodity status … at least as long as I’ve been in the industry,” Sprague says. “Secondly, I think it will allow engineers to more accurately specify an erosion control system.”
This may be especially beneficial for higher erosion risk designs, such as installations on steeper slopes and in high flow situations.
Jay Sprague spoke to Geosynthetica in the exhibit hall of the International Erosion Control Association (IECA Region One) Conference and Exhibition 2017. IECA 2018 will be held 11 – 14 February 2018 in Long Beach, California.
For more information on TRI Environmental’s work at DDRF, and to contact Jay Sprague on erosion and sediment control testing or to get involved in pullout anchor testing, visit www.erosiontest.com. For more information on IECA’s conferences, webinars, and other membership and education benefits, visit www.ieca.org.1