CEMP-E
EI 02G001
01 July 1997
CHAPTER 1
INTRODUCTION
1-1. PURPOSE. This document presents guidelines to assist the preparation of specifications for pile
installation and for assessment of construction operations.
1-2. SCOPE. Descriptions of types of piles, advantages, disadvantages, and usage of piles, equipment,
and installation methods are discussed in these instructions.
a. Equipment. Proper equipment and installation methods are critical to prevent damage to the pile
foundation during driving, to obtain adequate bearing capacity, and to minimize the cost of installation.
Guidance is provided for monitoring the installation of piles including equipment operation, prevention of pile
damage during installation, construction problems, and effects of driving on adjacent structures.
b. General Guidance. Guidance is provided on selection of equipment, verification of design,
construction considerations, and the care and maintenance of piles.
c. Installation Methods. Special installation methods are sometimes required depending on the soil
and the environment. Guidance is provided for pile installation assisted by jetting or where hammers or
vibrators are not or cannot be used.
d. Case History. A case history study is included as an example of how to proceed with installation of
a driven pile foundation. Guidance for design of driven piles is provided in TM 5-809-7.
e. Construction Guidance. Guidance for construction of drilled shafts is available in FHWA-HI-88-042
and Association of Drilled Shaft Contractors Publication.
1-3. REFERENCES. Appendix A contains a list of references used in this document.
1-4. HEARING CAUTION. Impact sound can exceed 140 decibels during pile driving operations.
Unprotected personnel exposed to these high sound levels can incur permanent hearing loss that becomes
worse over extended periods of time. A qualified industrial hygienist should be consulted to prescribe the
appropriate hearing protection necessary to preserve hearing.
1-5. DESCRIPTION OF PILES. The type of pile influences the method selected for installation. For
example, impact hammers may not be able to drive timber or closed-end pipe piles into firm ground without
damage to the pile, and assisted installation may be required.
a. Types of Piles. Piles are classified according to the amount of soil displacement that will occur
during installation. The soil is disturbed by driving causing cohesive clays to remold and cohesionless
sands to change density. The displaced soil can cause the ground surface around the pile to heave. Pile
driving can also cause the area around the pile to settle due to densification of a sand foundation material
when driving nondisplacement piles. Specifications for the piles given in tables 1-1 through 1-6 assume
that wave equation analysis was used for construction quality control.
(1) Displacement. These piles have a relatively large cross-sectional area. Driving these piles
displaces the soil a relatively large amount and can cause significant ground heave.
(a) Timber (TIM). TIM piles are the oldest deep foundation known. They are typically used as
round untrimmed logs cut to a suitable length, usually 20 to 66 feet with diameters from 6 to 16 inches as
shown in table 1-1. They may be sawed into square sections, but durability may be reduced because the
outer sapwood that best absorbs preservative is removed. TIM piles embedded below the ground-water
1-1
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