Evaluating the Seismic Stability and Performance of Freestanding Geofoam Embankment

The Utah Department of Transportation has made extensive use of expanded polystyrene (EPS) geofoam embankment at select locations on the I-15 Reconstruction Project in Salt Lake City, Utah. This paper presents a method to evaluate the seismic response and stability of a geofoam embankment for a nearby M7.0 earthquake. The recommended approach uses a finite difference numerical model implemented in FLAC (Fast Lagrangian Analysis of Continua) to evaluate the dynamic and deformation response of the geofoam embankment undergoing interlayer sliding and horizontal sway with rocking. The evaluations were performed in a coupled fashion using both the horizontal and vertical components of strong motion of a representative set of acceleration time histories for a nearby M7.0 earthquake. The analyses indicate that interlayer sliding is initiated in some cases and the amount of interlayer sliding displacement depends on the characteristics of the long-period strong motion and the interface properties used in the model. Shear keys strategically placed within the embankment are recommended where the estimated sliding displacements are potentially damaging. The numerical model also suggests that internal deformation caused by rocking and sway can cause local tensile yielding of some blocks within the embankment, usually near the base. In some cases, this yielding can propagate upward and cause the embankment to begin to decouple dynamically. Consideration should be given to using blocks with higher strengths than Type VIII geofoam in the basal zones of geofoam embankments undergoing high levels of strong motion.

  • Corporate Authors:

    Multidisciplinary Center for Earthquake Engineering Research

    State University of New York, 107 Red Jacket Quadrangle, P.O. Box 610025
    Buffalo, NY  United States  14261-0025
  • Authors:
    • Bartlett, Steven F
    • Lawton, Evert C
  • Conference:
  • Publication Date: 2008

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Photos; References; Tables;
  • Pagination: 15p
  • Monograph Title: Sixth National Seismic Conference on Bridges and Highways: Seismic Technologies for Extreme Loads

Subject/Index Terms

Filing Info

  • Accession Number: 01355907
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Oct 27 2011 1:38PM