This page was printed from

GSI to host webinar on stabilization of slopes with nailed or anchored geosynthetics

Events | October 2, 2020 | By:

The Geosynthetic Institute (GSI) will sponsor a webinar, “In-Situ Stabilization of Soil Slopes Using Nailed or Anchored Geosynthetics,” on October 21, from 11:30 a.m. to 1 p.m. EDT. Geosynthetic Materials Association (GMA) member companies and their employees receive discounted rates on all GSI webinar and short course registrations.

The sliding of soil slopes in the form of localized landslides represents an annual loss of $2–5 billion in America along with an associated 25 to 50 casualties. Theoretically, such failures are readily analyzed; e.g., simplified Bishop for rotational surfaces and Corps of Engineers wedge method for translational surfaces. For existing slopes that cannot be completely reconstructed due to structures at the top or toe of the slope, however, an in-situ remedial method is necessary. This webinar focuses on a geosynthetic placed on the existing soil’s surface and then nailed or anchored into the soil beyond the potential failure surface. Originally called “anchored spider-netting,” the method provides several benefits, each of which increases the factor-of-safety (FS), for example,

  • increases soil friction
  • increases soil cohesion
  • nails penetrate the failure plane
  • geosynthetic force is added along potential failure plane
  • moment due to geosynthetic at ground surface exists

Numeric examples including the above-listed benefits are given illustrating the resulting increases in FS values.

Original field trials in the 1980s are shown using a gathered-knit geotextile and hand-driven soil nails. Interestingly all activity then ceased for some twenty years. Perhaps the 1986 patent on the technique thwarted the method’s implementation? Since 2010, however, at least ten manufacturers, contractors or developers have taken up the concept using different soil-covering materials as well as various nailing or anchoring systems. Each of these newer methods will be illustrated with a comparison made at the conclusion of the webinar.

Learning objectives

Participants will become familiar with details of this in-situ soil slope stabilization method. It is indeed a juxtaposition of geosynthetics and ground modification. The FS improvements are illustrated by means of theory and examples, as well as description of the commercially available approaches to the technique. This webinar will hopefully lead to mitigating the large number of shallow soil slope failures along our highways as well as on private and public lands.

Webinar benefits

  • Understand the nature and magnitude of soil slope failures
  • Learn about the underlying theory of landslides
  • Learn how the theory is modified using this technique
  • Learn about the initial field trials
  • Be exposed to the wide variety of presently available installations
  • Appreciate the differences of the currently available method

Intended audiences

This webinar will be beneficial to owners of sensitive or quasi-stable soil slopes in both the public and private sectors; federal, state and regional geotechnical, transportation and environmental engineers; engineers from municipal districts and townships; private and municipal land developers, architectural and landscape designers; general civil consulting engineers; testing laboratories servicing these organizations; manufacturers and representatives of geosynthetic materials; ground modification contractors and installers of in-situ soil slope stabilization methods; academic and research groups; and others desiring technically related information on this important aspect of our constructed infrastructure.

Webinar instructor

George R. Koerner, Ph.D., P.E., and CQQ is the director of the Geosynthetic Institute. He is in charge of laboratory accreditation, field certification and continuing education at the institute. He also manages several research projects and has published more than 350 technical papers in his 35-year association with polymers used in below-ground construction. Koerner’s Ph.D. is from Drexel University in geotechnical engineering. He is a registered professional engineer and a certified quality auditor. Koerner has received many awards over the years. The most notable being IFAI’s Environmental Technologies Award of Excellence 1995, ASCE’s DVGI Geotechnical Engineer of the year in 2004, the title of ASTM Fellow in 2013 and GMA’s first Robert M. Koerner Lecture and Award in 2017.


Webinars cost $200.00 for GSI and GMA members, and $250.00 for nonmembers. Successful completion of a multiple-choice test after the webinar carries 1.5 professional development hours (PDH).

For more information or to register, visit

Share this Story