NEHRP Clearinghouse
- Title
- Draft Guidelines for Evaluating Liquefaction Resistance Using Shear Wave Velocity Measurements and Simplified Procedures.
- File
- PB99117897.pdf
- Author(s)
- Andrus, R. D.; Stokoe, K. H.; Chung, R. M.
- Source
- March 1999, 140 p.
- Identifying Number(s)
- NISTIR-6277
- Abstract
- Predicting the liquefaction resistance of soil is an important step in the engineering design of new and the retrofit of existing structures in earthquake-prone regions. The procedure currently used in the U.S. and throughout much of the world to predict liquefaction resistance is termed the simplified procedure. This simplified procedure was originally developed by H. B. Seed and I. M. Idriss in the late 1960s using blow count from the Standard Penetration Test. Small-strain, shear wave velocity measurements provide a promising alternative and/or supplement to the penetration-based approach. This report presents draft guidelines for evaluating liquefaction resistance using shear wave velocity measurements. These draft guidelines were written in cooperation with industry, researchers and practitioners, and evolved from workshops in 1996 and 1998. The guidelines outline the development of a recommended procedure, which follows the general format of the penetration-based simplified procedure. The proposed procedure has been validated through case history data from more than 20 earthquakes and 70 measurement sites in soils ranging from clean fine sand to sandy gravel with cobbles to profiles including silty clay layers.
- Keywords
- ; Seismic design; Retrofitting; Buildings; Earthquake engineering; Secondary waves; Soil properties; Cyclic loads; Liquefacti9on