Geotechnical Design Manual
The Geotechnical Design Manual focuses on geotechnical design, construction, and maintenance to ensure that the soil or rock beneath the ground surface can support the loads and conditions placed on it by transportation facilities.
Individual Chapters
Chapter 1 Geotechnical Operations and Administration (PDF 656KB)
Chapter 2 Project Geotechnical Planning (PDF 444KB)
Chapter 3 Field Investigation (PDF 813KB)
Chapter 4 Soil and Rock Classification and Logging (PDF 674KB)
Chapter 5 Engineering Properties of Soil and Rock (PDF 3.26MB)
Chapter 6 Seismic Design (PDF 4.06MB)
Chapter 7 Slope Stability Analysis (PDF 478KB)
Chapter 8 Foundation Design (PDF 6.73MB)
Chapter 9 Embankments (PDF 2.3MB)
Chapter 10 Soil Cut Design (PDF 3.61MB)
Chapter 11 Gound Improvement (PDF 256KB)
Chapter 12 Rock Cut Design (PDF 248KB)
Chapter 13 Landslide Analysis and Mitigation (PDF 207KB)
Chapter 14 Unstable Rockslope Analysis and Mitigation (PDF 242KB)
Chapter 15 Abutments, Retaining Walls, and Reinforced Slopes (PDF 82.9MB)
Chapter 16 Geosynthetic Design (PDF 217KB)
Chapter 17 Foundation Design for Signals, Signs, Noise Barriers Culverts, and Buildings (PDF 799KB)
Chapter 18 Geotechnical Design for Marine Structure Foundations (PDF 208KB)
Chapter 19 Infiltration Facility Design (PDF 267KB)
Chapter 20 Unstable Slope Management (PDF 1218KB)
Chapter 21 Materials Source Investigation and Report (PDF 394KB)
Chapter 23 Geotechnical Reporting and Documentation (PDF 835KB)
Revision History
February 2022
December 2021
June 2021
December 2020
July 2019
May 2015
August 2014
December 2013
October 2013
April 2012
November 2011
August 2011
April 2011
November 2010
July 2010
January 2010
November 2008
166,800 electric vehicle
registrations in Washington in 2023, up from 114,600 in 2022.
87 wetland compensation sites
actively monitored on 918 acres in 2023.
25,000 safe animal crossings
in the Snoqualmie Pass East Project area since 2014.