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TRB's National Cooperative Highway Research Program (NCHRP) Web-Only Document 258: Manual on Subsurface Investigations provides an update to the American Association of State Highway Transportation Officials (AASHTO) 1988 manual of the same name. This report reflects the changes in the approaches and methods used for geotechnical site characterization that the geotechnical community has developed and adopted in the past thirty years. The updated manual provides information and guidelines for planning and executing a geotechnical site investigation program. It may also be used to develop a ground model for planning, design, construction, and asset management phases of a project.

Suggested Citation

National Academies of Sciences, Engineering, and Medicine. 2019. Manual on Subsurface Investigations. Washington, DC: The National Academies Press.

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Publication Info

372 pages |  8.5 x 11 |  DOI:

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