EM 1110-1-1804 1 January 2001 US Army Corps of Engineers ENGINEERING AND DESIGN Geotechnical Investigations ENGINEER MANUAL Report Documentation Page Report Date Report Type Dates Covered (from... to) 01 Jan 2001 N/A - Title and Subtitle Contract Number Geotechnical Investigations Grant Number Program Element Number Author(s) Project Number Task Number Work Unit Number Performing Organization Name(s) and Address(es) Performing Organization Report Number Department of the Army U.S. Army Corps of Engineers EM1110-1-1804 Washington, DC 20314-1000 Sponsoring/Monitoring Agency Name(s) and Sponsor/Monitor’s Acronym(s) Address(es) Sponsor/Monitor’s Report Number(s) Distribution/Availability Statement Approved for public release, distribution unlimited Supplementary Notes Abstract Subject Terms Report Classification Classification of this page unclassified unclassified Classification of Abstract Limitation of Abstract unclassified UU Number of Pages 449 AVAILABILITY Electronic copies of this and other U.S. Army Corps of Engineers (USACE) publications are available on the Internet at http://www.usace.army.mil/inet/usace-docs/. This site is the only repository for all official USACE engineer regulations, circulars, manuals, and other documents originating from HQUSACE. Publications are provided in portable document format (PDF). DEPARTMENT OF THE ARMY EM 1110-1-1804 U.S. Army Corps of Engineers CECW-ET Washington, DC 20314-1000 Manual No. 1110-1-1804 1 January 2001 Engineering and Design GEOTECHNICAL INVESTIGATIONS 1. Purpose. This manual establishes criteria and presents guidance for geotechnical investigations during the various stages of development for both civil and military projects. 2. Applicability. This manual applies to all USACE Commands having either military or civil works responsibilities. 3. Distribution Statement. This manual is approved for public release; distribution is unlimited. 4. Discussion. Geotechnical investigations are made to determine those geologic, seismologic, and soils conditions that affect the safety, cost effectiveness, design, and execution of a proposed engineering project. Because insufficient geotechnical investigations, faulty interpretation of results, or failure to portray results in a clearly understandable manner may contribute to costly construction changes, postconstruction remedial work, and even failure of a structure, geotechnical investigations and subsequent reports are an essential part of all civil engineering and design projects. FOR THE COMMANDER: ROBERT L. DAVIS Colonel, Corps of Engineers Chief of Staff This manual supersedes EM 1110-1-1804, dated 29 February 1984, and EM 1110-1-1906, dated 30 September 1996. DEPARTMENT OF THE ARMY EM 1110-1-1804 U.S. Army Corps of Engineers CECW-ET Washington, DC 20314-1000 Manual No. 1110-1-1804 1 January 2001 Engineering and Design GEOTECHNICAL INVESTIGATIONS Table of Contents Subject Paragraph Page Chapter 1 Introduction Purpose .......................................................... 1-1 1-1 Applicability ..................................................... 1-2 1-1 References ....................................................... 1-3 1-1 Background ...................................................... 1-4 1-1 Scope of Manual .................................................. 1-5 1-2 Chapter 2 Scope of Investigations Background ...................................................... 2-1 2-1 Section I Civil Works Projects Reconnaissance and Feasibility Studies ................................ 2-2 2-1 Preconstruction Engineering and Design Studies ......................... 2-3 2-6 Construction Activities ............................................. 2-4 2-13 Section II Military Construction Projects Background ...................................................... 2-5 2-17 Preconcept and Site Selection Studies .................................. 2-6 2-18 Concept Studies ................................................... 2-7 2-18 Final Design Studies ............................................... 2-8 2-19 Construction Activities ............................................. 2-9 2-19 Chapter 3 Regional Geologic and Site Reconnaissance Investigations Background ...................................................... 3-1 3-1 Section I Coordination and Information Collection Interagency Coordination and Cooperation .............................. 3-2 3-1 Survey of Available Information ...................................... 3-3 3-3 i EM 1110-1-1804 1 Jan 01 Subject Paragraph Page Section II Map Studies and Remote Sensing Methods Map Studies ...................................................... 3-4 3-3 Remote Sensing Methods ........................................... 3-5 3-9 Section III Field Reconnaissance and Observations Field Reconnaissance ............................................... 3-6 3-10 Observations ..................................................... 3-7 3-10 Section IV Information Development Summary ........................................................ 3-8 3-11 Chapter 4 Surface Investigations Background ...................................................... 4-1 4-1 Section I Geologic Field Mapping Areal Mapping .................................................... 4-2 4-1 Site Mapping ..................................................... 4-3 4-2 Construction Mapping .............................................. 4-4 4-3 Section II Surface Geophysical Explorations Background ...................................................... 4-5 4-4 Methods ......................................................... 4-6 4-4 Chapter 5 Subsurface Investigations Background ...................................................... 5-1 5-1 Location of Investigations ........................................... 5-2 5-1 Protection of the Environment ........................................ 5-3 5-1 Section I Borings Major Uses ....................................................... 5-4 5-2 Boring and Sampling Methods ....................................... 5-5 5-2 Drilling in Embankments ............................................ 5-6 5-8 Section II Drillhole Inspection and Logging Objectives ....................................................... 5-7 5-8 Soil Identification and Description .................................... 5-8 5-9 Coring .......................................................... 5-9 5-9 ii EM 1110-1-1804 1 Jan 01 Subject Paragraph Page Core Logging .................................................... 5-10 5-10 Drilling Log Form and the Boring Log Data Management Program.......... 5-11 5-14 Section III Borehole Examination and Testing Borehole Geophysical Testing ....................................... 5-12 5-14 Borehole Viewing and Photography .................................. 5-13 5-14 Borehole Camera and Borescope ..................................... 5-14 5-15 Borehole TV Camera and Sonic Imagery .............................. 5-15 5-15 Alinement Surveys ................................................ 5-16 5-15 Section IV Exploratory Excavations Test Pits and Trenches ............................................. 5-17 5-15 Calyx Hole Method ............................................... 5-18 5-16 Section V Groundwater and Foundation Seepage Studies General Investigation .............................................. 5-19 5-16 Permeability Testing .............................................. 5-20 5-17 Pressure Tests ................................................... 5-21 5-21 Section VI In Situ Testing for Determining Geotechnical Properties In Situ Testing ................................................... 5-22 5-22 In Situ Tests to Determine Shear Strength.............................. 5-23 5-23 Tests to Determine In Situ Stress ..................................... 5-24 5-25 Tests to Determine In Situ Deformation ............................... 5-25 5-27 Determination of Dynamic Moduli by Seismic Methods .................. 5-26 5-29 Section VII Backfilling of Holes and Disposition of Samples and Cores Backfilling Boreholes and Exploratory Excavations ...................... 5-27 5-30 Disposition of Soil Samples ......................................... 5-28 5-30 Disposition of Rock Cores .......................................... 5-29 5-30 Chapter 6 Large-scale, Prototype Investigations Prototype Test Programs ............................................ 6-1 6-1 Section I Test Excavation and Fills Accomplishments .................................................. 6-2 6-1 Test Quarries ..................................................... 6-3 6-1 Exploratory Tunnels ............................................... 6-4 6-3 Test Fills and Trial Embankments ..................................... 6-5 6-3 iii EM 1110-1-1804 1 Jan 01 Subject Paragraph Page Section II Test Grouting Purpose .......................................................... 6-6 6-5 Test Grouting Practices ............................................. 6-7 6-5 Test Grouting Program ............................................. 6-8 6-5 Record Keeping ................................................... 6-9 6-5 Section III Piling Investigations Piling Investigation Benefits ........................................ 6-10 6-6 Driving Records .................................................. 6-11 6-6 Load Testing .................................................... 6-12 6-6 Chapter 7 Laboratory Investigations Purpose .......................................................... 7-1 7-1 Section I Test and Sample Selection Needs for Test and Sample Selection .................................. 7-2 7-1 Section II Index and Classification Tests Soils ............................................................ 7-3 7-3 Rock ............................................................ 7-4 7-4 Section III Engineering Property Tests - Soils Background ...................................................... 7-5 7-5 Section IV Engineering Property Tests - Rock Background ...................................................... 7-6 7-6 Section V Engineering Property Tests - Shales and Moisture-Sensitive Rocks Index Testing ..................................................... 7-7 7-8 Swelling Properties ................................................ 7-8 7-9 Appendix A References Appendix B Geologic Mapping Procedures Open Excavations Appendix C Geologic Mapping of Tunnels and Shafts iv EM 1110-1-1804 1 Jan 01 Appendix D Examples of Drilling Logs Appendix E List of Acronyms Appendix F Engineer Manual 1110-1-1906, Soil Sampling Appendix G Penetration Resistance Test and Sampling with a Split-Barrel Sampler Appendix H Penetration Resistance Testing with the Becker Hammer Drill v EM 1110-1-1804 1 Jan 01 Chapter 1 Introduction 1-1. Purpose This manual establishes criteria and presents guidance for geotechnical investigations during the various stages of development for civil and military projects. The manual is intended to be a guide for planning and conducting geotechnical investigations and not a textbook on engineering geology and soils explora- tion. Actual investigations, in all instances, must be tailored to the individual projects. 1-2. Applicability This manual applies to all USACE Commands having either military or civil works responsibilities. The objective of Corps of Engineers Engineer Manuals (EM)1 is to contain engineer and design technical guidance that will provide essential technical direction and application within the COE. However, an EM cannot provide the designer with two of the most vital tools essential to successful completion of a project: experience and judgement. Engineers and geologists who are just beginning their careers are strongly encouraged to seek the advice of more experienced members of their organization. 1-3. References Standard references pertaining to this manual are listed in Appendix A. Military Standards (MIL-STD), Army Regulations (AR), Technical Manuals (TM), Engineer Regulations (ER), Engineer Manuals (EM), Engineer Pamphlets (EP), and Engineer Technical Letters (ETL) are identified in the text by the designated Government publication number or performing agency. Additional reading materials are listed in the Bibliography and are indicated throughout the manual by the principal author’s last name and date of publication. Publications may be downloaded from the internet at the Corps’ web page (www.usace.army.mil/inet/usace-docs/). 1-4. Background Geotechnical investigations are performed to evaluate those geologic, seismologic, and soils conditions that affect the safety, cost effectiveness, design, and execution of a proposed engineering project. Insufficient geotechnical investigations, faulty interpretation of results, or failure to portray results in a clearly understandable manner may contribute to inappropriate designs, delays in construction schedules, costly construction modifications, use of substandard borrow material, environmental damage to the site, postconstruction remedial work, and even failure of a structure and subsequent litigation. Investigations performed to determine the geologic setting of the project include: the geologic, seismologic, and soil conditions that influence selection of the project site; the characteristics of the foundation soils and rocks; geotechnical conditions which influence project safety, design, and construction; critical geomorphic processes; and sources of construction materials. A close relationship exists between the geologic sciences and other physical sciences used in the determination of project environmental impact and mitigation of that impact. Those individuals performing geotechnical investigations are among the first to assess the physical setting of a project. Hence, senior-level, experienced personnel are required to plan and supervise the execution of a geotechnical investigation. Geotechnical investigations are to be 1 A list of acronyms and abbreviations is included as Appendix E to this manual. 1-1