**SPECIAL SPECIFICATION**

**SECTION 02372**

**[DRILLED SHAFT FOUNDATIONS]{.underline}**

[Page]{.underline}

PART 1 - GENERAL

1.01 References 1

1.02 Submittals 1

1.03 Quality Assurance 2

PART 2 - PRODUCTS

2.01 Materials 3

PART 3 - EXECUTION

3.01 Preparation 4

3.02 Construction Methods 4

3.03 Reinforcing Steel 4

3.04 Concrete 4

3.05 Cleaning 5

**SPECIAL SPECIFICATION**

**SECTION 02372**

**[DRILLED SHAFT FOUNDATIONS]{.underline}**

[PART 1 - GENERAL]{.underline}

1.01 [REFERENCES]{.underline}

A. AMERICAN CONCRETE INSTITUTE (ACI)

ACI 336.1 Construction of Drilled Piers, Standard Spec. for the

B. AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM)

ASTM A501 Hot-Formed Welded and Seamless Carbon Steel Structural Tubing,
Standard Spec. for

1.02 [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.

1.03 [QUALITY ASSURANCE]{.underline}

A. [Tolerances]{.underline}

1\. Centerline of drilled shafts: Within 3 in. of plan location.

2\. Vertical drilled shafts: Plumb to within 1-1/2 in. first 10 ft.,
plus 1 percent of depth greater than 10 ft.

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

B. [Codes and Standards]{.underline}

1\. Perform drilled shaft work in compliance with applicable
requirements of governing authorities having jurisdiction.

C. [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.

[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 03300 \"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. [Caving]{.underline}

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

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

3.05 [CLEANING]{.underline}

A. Dispose of excavated material from shafts off site.

END OF SECTION