SECTION 02365

PRESSURE INJECTED FOOTINGS

PART 1 GENERAL

SECTION INCLUDES

Machine drilled shaft[.] [and placement of shaft liner.]

Placing concrete and compacting to achieve bulbular base to support design loads.

RELATED WORK

Section [_____] - Information Available To Bidders: Subsurface Investigation Report.

Section [01400 - Quality Control] [01410 - Testing Laboratory Services]: Testing laboratory services.

Section 02222 - Excavation: Excavation to working level.

Section 02356 - Pile Load Tests: Requirements for footing load tests.

Section [_____-__________]: [Caps] [and][.] [grade beams.]

Section 03200 - Concrete Reinforcement: Requirements for concrete reinforcement.

Section 03300 - Cast-In-Place Concrete: Requirements for concrete.

SYSTEM DESCRIPTION

End bearing cast-in-place concrete footing, compacted in place to form an expanded bulbular base.

PERFORMANCE REQUIREMENTS

Place footings to [defined] load supporting capacity. Avoid damaging footings by over compacting.

Load Supporting Capacity: [[___] lb ([___] kg).] [As indicated.] [__________.]

SUBMITTALS

Submit under provisions of Section [01300.] [_____.]

Indicate schedule of footing installation, identify recommended footing lengths and diameters to suit design requirements, [reinforcing requirements] [and][.] [__________.]

PROJECT RECORD DOCUMENTS

Submit under provisions of Section [01700.] [_____.]

Accurately record the following:

Sizes, lengths, and locations of footings[.] [and footing groups.]

Sequence of placement.

Drilling: Hole diameters.

For footings closer than [nine] [___] shaft diameters, record elevations of adjacent footings before and after placement, to determine if movement has occurred.

Final shaft base elevations.

Deviation from indicated locations.

Ramming force and number of blows required for form expanded bases.

Other pertinent information including interruption of continuous placement, or footing damage.

QUALIFICATIONS

Installer: Company specializing in performing the Work of this Section with minimum [___] years [documented] experience.

Design and select footing components under direct supervision of a Professional Structural Engineer experienced in design of this work and licensed [at the place where the Project is located.] [in the State of [_______________].]

REGULATORY REQUIREMENTS

Conform to [applicable] [__________] code for seismic requirements for footings.

Provide certificate of compliance from [authority having jurisdiction] [_______________] indicating approval.

PRE-INSTALLATION CONFERENCE

Convene [one] [___] week prior to commencing work of this Section, under provisions of Section [01039.] [_____.]

FIELD MEASUREMENTS

Verify that field measurements and survey benchmarks are as indicated on Drawings.

SCHEDULING

Schedule work under the provisions of Section [01300.] [_____.]

Schedule Work to perform ramming during [___] and [___] hours.

Schedule [test] [indicator] piles.

PART 2 PRODUCTS

MATERIALS

Concrete Materials, Mix, Reinforcement, Shaft Liner: As required to achieve design and performance criteria.

****** [OR] ******

Concrete Materials and Mix: Specified in Section [03300] [_____] using Type [___] cement, maximum [___] aggregate size, [___] psi ([___] MPa) 28 day strength, [___] inch ([___] mm) slump.

[Reinforcement: Specified in Section [03200] [_____] [spiral wound].]

Liner: [_______________.]

PART 3 EXECUTION

EXAMINATION

Verify site conditions under provisions of Section [01039.] [_____.]

Verify that site conditions will support equipment for performing footing placement and ramming operations.

PREPARATION

Use ramming method which will not cause damage to nearby structures.

Notify adjacent and affected land owners and building occupants [with [___] days] notice before proceeding with the Work.

Protect structures near the Work, from damage.

INSTALLATION

Drill concentric and vertical footing shafts.

[Place steel liners immediately after drilling. Set firmly in place.]

Clean shaft and bottom of loose material.

Allow inspection of shaft [and liner] prior to placement of [reinforcement and] concrete.

[Place reinforcing steel in accordance with Section [03200] [_____].]

Place concrete in accordance with Section [03300] [_____] with equipment designed for vertical placement of concrete and in conjunction with ramming operations.

Deposit concrete in bottom of shaft, ram into subsoil with hammer blows.

Do not place adjacent footings less than 24 hours after previous footings have been formed unless footings are more than [[five] [___] shaft diameters] [[___] ft ([___]

apart, measured center to center][,][.] [based on the

larger adjacent shaft.]

Install footings to required elevations and load capacities.

****** [OR] ******

Install footings to refusal, not less than [___] blows [required to inject last batch of concrete.] [per unit length.]

Successively repeat ramming and expelling of concrete into underlying soil until expanded bulbular base is formed. Develop maximum surface friction with subsoil.

[Progressively raise shaft liner.]

Replace [or supplement] footings which have lifted or moved due to placing and ramming adjacent footings, or by soil uplift.

[Extend reinforcement] [Provide dowels] for connection of [caps.] [grade beams.]

TOLERANCES

Maximum Variation From Vertical: 1 in [48.] [___.]

Top Elevation: Maximum [4] [___] inches ([100] [___] mm) from elevation indicated.

FIELD QUALITY CONTROL

Field inspection will be performed under provisions of Section [01400.] [01410.] [_____.]

Perform load tests to requirements of Section [02356.] [_____.]

Test Piles: Same diameter and type as specified for other piling, placed in same manner.

Accepted test piles may [not] be used in the Work.

UNACCEPTABLE FOOTINGS

Unacceptable Footings: Footings that fail tests, are placed out of position, are below top of shaft elevations or are damaged.

Provide additional footings or replace footings failing to conform to specified requirements.

END OF SECTION