NEHRP Clearinghouse
- Title
- Estimating In situ Liquefaction Potential and Permanent Ground Displacements Due to Liquefaction for the Siting of Lifelines.
- File
- PB93178614.pdf
- Author(s)
- Glaser, S. D.
- Source
- March 1993, 108 p.
- Identifying Number(s)
- NISTIR-5150
- Abstract
- The report examines the state-of-the-art of two aspects of the liquefaction problem with special attention to lifelines. In situ methods of estimating liquefaction potential are studied, since it is believed to be impossible to test in the laboratory an 'undisturbed' sample of loose sand, which is most susceptible to liquefaction. The state-of-practice is the SPT-based method championed by Seed, although the velocity-based predictors have a stronger physical basis. The Spectral Analysis of Surface Waves technique is especially suited for examining the large areal extents of lifeline routes. The state-of-the-art for estimating permanent ground displacements is purely empirical. Several methods are examined, and they all appear to have equal predictive abilities - within a factor of four. There have been a few recent attempts to construct constitutive models for post-liquefaction displacements, but at the time they are in formative stages and have not been rigorously proven.
- Keywords
- ; Earthquake resistant structures; Seismic waves; Mathematical models; Earth movements; Liquefaction; Displacement; Soil properties; Sands; Soil mechanics; Earthquakes