SPECIAL SPECIFICATION

SECTION 02372

[DRILLED PIER FOUNDATIONS]{.underline}

[PART 1 - GENERAL]{.underline}

1.01 DESCRIPTION OF WORK 2

1.02 REFERENCES 2

1.03 SUBMITTALS 2

1.04 QUALITY ASSURANCE 2

1.05 PROJECT CONDITIONS 3

[PART 2 - PRODUCTS]{.underline}

2.01 MATERIALS 3

[PART 3 - EXECUTION]{.underline}

3.01 PREPARATION 3

3.02 CONSTRUCTION METHODS 3

3.03 REINFORCING STEEL 4

3.04 CONCRETE 4

3.05 CLEANING 4

SPECIAL SPECIFICATION

SECTION 02372

[DRILLED PIER FOUNDATIONS]{.underline}

[PART 1 - GENERAL]{.underline}

1.01 [DESCRIPTION OF WORK]{.underline}

A. [This section includes]{.underline} requirements for drilled,
cast-in-place reinforced concrete friction bearing pier construction.
The extent of drilled pier work is shown on the drawings, including
locations, diameters, depths, and details of construction.

B. [Related Section:]{.underline} Refer to Division 3 "Cast-in-Place
Concrete" for concrete and reinforcing steel requirements to supplement
the requirements specified herein.

1.02 [REFERENCES]{.underline}

A. AMERICAN CONCRETE INSTITUTE (ACI)

ACI 336.1 Standard Specification for the construction of Drilled Piers.

1.03 [SUBMITTALS]{.underline}

A. Submit drilling log to include the following:

1\. Pier depths for each pier.

2\. Final centerline location at top.

3\. Variation of shaft from plumb.

4\. Date of excavation completion.

5\. Date of concrete placement.

6\. Diameter of shaft.

1.04 [QUALITY ASSURANCE]{.underline}

A. [Codes and Standards]{.underline}

1\. Comply with all provisions of ACI 336.1 and as specified herein.

B. [Inspection Control]{.underline}

1\. SDR will determine that shafts are properly clean and dry before
placing

concrete.

2\. All drilled pier excavations shall be inspected and approved prior
to

placing the concrete.

3\. Notify SDR no later than 24 hours before drilling is to begin.

1.05 [PROJECT CONDITIONS]{.underline}

1\. [Existing Utilities:]{.underline} Locate existing underground
utilities before starting drilled pier excavation operations. If
utilities are to remain in place, provide protection from damage during
drilled pier operations.

2\. If uncharted or incorrectly charted piping or other utilities are
encountered during excavation, notify the Sandia Delegated
Representative (SDR) immediately.

[PART 2 - PRODUCTS]{.underline}

2.01 [MATERIALS]{.underline}

A. [Concrete and Reinforcing]{.underline}

1\. All concrete shall be 3000 psi and shall conform to Division 3,
Section

"Cast-in-Place Concrete."

[PART 3 - EXECUTION]{.underline}

3.01 [PREPARATION]{.underline}

A. Excavation shall be free of water and loose material.

3.02 [CONSTRUCTION METHODS]{.underline}

A. [Excavation]{.underline}

1\. Excavate to dimensions and elevations shown on Drawings or required
by

site conditions.

B. [Tolerances]{.underline}

1\. Centerline of drilled shafts: Within 1-1/2 in. of plan location.

2\. Vertical drilled shafts: Plumb to within 2-1/2 in. for each 20 ft.

of depth.

3\. Tolerance for shaft top elevations: Plus 1 in., minus 3 in.

C. [Caving]{.underline}

1\. When drilling operation reaches a point where caving conditions are

encountered, do not drill further until construction method is employed

which will minimize caving.

3.03 [REINFORCING STEEL]{.underline}

A. Assemble and place reinforcing steel cage in shaft as unit.

B. Place concrete after cage is positioned and secure against movement.

C. Use side spacer blocks of concrete at intervals along shaft to ensure

concentric spacing for entire length of shaft, or place metal chair-type

spacers vertically at intervals around steel cage to ensure concentric

spacing inside shaft.

3.04 [CONCRETE]{.underline}

A. Place concrete as soon as possible after excavation is complete.

B. In any event, holes shall not remain open for more than 8 hours.

C. Place concrete continuously without cold joints.

D. Place concrete through suitable tremie or other means to prevent
segregation

> of concrete materials and splashing reinforcing steel cage. Aluminum
> pipe or aluminum equipment shall not be used for placing concrete.

E. The top 5 feet of concrete shall be vibrated to ensure proper
consolidation.

3.05 [CLEANING]{.underline}

A. Dispose of excavated material from shafts off site.

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