Simplified Standard Penetration Test Performance-Based Assessment of Liquefaction and Effects

The purpose of the research presented is to provide the benefit of the full performance-based probabilistic earthquake hazard analysis, without requiring special software, training, and experience, while using Standard Penetration Test (SPT) data from site soil borings. To do this, simplified models of liquefaction triggering, lateral spread displacements, post-liquefaction settlements, and seismic slope displacements that approximate the results of the full probabilistic analysis were developed. These simplified methods are designed to require only a few calculations programmed into a spreadsheet and a provided liquefaction parameter map. The simplified procedures are based on the Boulanger and Idriss (2012) probabilistic liquefaction triggering; Youd et al. (2002) for lateral spread; Cetin et al. (2009) and (Ishihara and Yoshimine (1992) for post-liquefaction settlements; and lastly, Rathje & Saygili (2009), and Bray & Travasarou (2007) for seismic slope displacement empirical models. The new simplified procedures are based on retrieving a reference parameter value (i.e. CSRref (%), log D sub Href, etc.) from a hazard-targeted liquefaction parameter map, and calculating site-specific correction factors to adjust the reference value to represent the site-specific conditions. The simplified procedures were validated by comparing the results of the simplified analysis with a full performance-based analysis for 10 cities of varying seismicity. The results show that the simplified procedure is within 5% error of the full performance-based procedure. These maps were created for Alaska (only liquefaction triggering and lateral spread), Connecticut, Idaho, Montana, South Carolina, Oregon, and Utah at the 475, 1033, and 2475 year return periods. The simplified procedures were compared with the deterministic and pseudo-probabilistic procedures. The deterministic procedure significantly overpredicts hazard in regions of low seismicity, slightly overpredicts hazard in regions of medium seismicity, and slightly underpredicts hazard in areas of high seismicity when compared to the simplified procedure at the 475 and 2475 year return periods. The pseudo-probabilistic procedure returns results very similar to the simplified method at the 1033 year return period.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 371p

Subject/Index Terms

Filing Info

  • Accession Number: 01702431
  • Record Type: Publication
  • Report/Paper Numbers: UT-16.16
  • Contract Numbers: 148753
  • Created Date: Apr 22 2019 9:27PM