Attachment 2 - Specifications_1.pdf

MINOR CONCRETE

Sign Base [7/00]

03306 - 1

SECTION 03306

SIGN BASE CONSTRUCTION

PART 1: GENERAL

1.1 SUMMARY

A. Section Includes: Site preparation, furnishing and placing cast-in-place concrete, including formwork and reinforcement, rock cladding and sign install. NOTE: a precast sign base construction method may be approved by the COR.

1.2 SUBMITTALS

A. General: Submittals shall be submitted prior to ordering concrete and shall include project name, submit to the COR by email.

B. Inspect signs to be installed, adjust typical drawing dimensions and sign erection detail accordingly and submit proposed dimension to COR for approval.

1.3 QUALITY ASSURANCE

A. General: Forming, installing steel reinforcement, placing, and finishing concrete within the sign slab shall be performed with experienced concrete worker whose full time position(s) are involved with the preparation and placement of concrete.

B. Testing: Testing will be at the discretion of the BLM COR, or BLM engineer.

C. Causes for Rejection: Concrete may be rejected for, but not limited to, the following reasons:

1. Freezing within the first 3 days of placement

2. Excessive or inadequate slump

3. Segregation of aggregate or over-vibration resulting in excessive water in the surface of the concrete

4. Honeycomb over 25% of the surface

5. Voids larger than 2 inches across

6. Exposed reinforcing steel

7. Misalignment of concrete

8. Substandard aggregate in the mix

9. Failure to apply cure/sealer within 24 hour after completion of pour.

PART 2: PRODUCTS

2.1 MATERIALS

A. General: Concrete shall be ready mix as per 2.1 B with the option of using bag concrete as per 2.1 C for construction of the concrete sign pad.

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B. Ready Mix Concrete: Ready-mixed concrete shall be according to

ASTM C 94 and be designed for a 28-day compressive strength of 4000 psi, and a maximum slump of 4 inches as determined by ASTM C 143.

C. Sack Concrete Mix: Shall be designed for a 28-day compressive strength of 4000 psi, and a slump of 4 inches as determined by ASTM C

143.

D. Concrete Curing Compound: Clear all resin, dissipating water based curing compound, meeting ASTM C-309 requirements. Dayton Superior

J11W or approved equal.

E. Reinforcing Steel: Shall have a yield point of 60 ksi, and shall be according to grade 60 of ASTM A 615. The size of the bars and mesh shall be as indicated on the drawings.

F. Fiber: 100% virgin polypropylene, fibrillated fibers specifically manufactured for use as concrete secondary reinforcement, installed at

1.5 pounds per cubic yard of concrete.

G. Water: Potable water shall be used for mixing concrete.

H. Air-Entraining Admixture: ASTM C260. The amount of air shall be 4 to

6 percent when maximum aggregate size is 3/4-inch, and 4.5 to 7.5 percent when maximum aggregate size is 3/8-inch. A variations of plus or minus 1 percent is allowable.

I. Expansion Joint Material: Preformed filler strips shall be according to ASTM D 994 and shall be the full width and depth of the joint.

Unless otherwise indicated, the material shall be 1/2-inch thick.

J. Expansion/Control Joint Sealant: Shall be a two-part polysulfide modified polyurethane sealant, non-staining, able to withstand constant water immersion, and capable of 25% joint movement.

Sonolastic Polysulfide Sealant as manufactured by Sonneborn, Division of BASF, 800-433-9517 or www.buildingsystems.basf.com, or approved equal. Color of sealant shall be “Desert Tan”. Primers and Backer-

Rod required with the installation of the sealant shall be as recommended by the manufacturer.

K. Capstone shall be nominal 2-inch thick cut to provide finished product as shown on sample base photo. Some irregularities in dimensions shall be allowed as approved by COR. Color shall be a desert tan or sand type color similar to sample photo. If using manufactured stone meet

IBC 2015 and ASTM C1670 form minimum 1800 psi compressive strength, minimum 50 psi shear bond, freeze thaw less than 3%. Provide manufacturers warrantee.

L. Ledgestone facing for sides of base shall be of a linear design and color similar to the sample base photo. If using manufactured stone meet IBC 2015 and ASTM C1670 form minimum 1800 psi compressive http://www.buildingsystems.basf.com/

03306 - 3 strength, minimum 50 psi shear bond, freeze thaw less than 3%.

Provide manufacturers warrantee.

G. Mortar shall be Pre-packaged Latex-Portland Cement Mortar ANSI A118.4

Type S (severe weather), tinted to blend with stone.

H. Masonry reinforcing shall be ASTM C 1032 17 gage woven wire mesh complying with code agency for substrate.

PART 3: EXECUTION

3.1 PREPARATION

A. Subbase Preparation: Subbase and earth walls to be in contact with concrete shall be prepared undisturbed soil or moisture conditioned and compacted to 95% maximum dry density. Any soft or unsuitable soils shall be removed and replaced with compacted soil.

B. Form Construction: ACI 347R. Construct forms to the sizes, shapes, lines, and dimensions shown on the drawings. The Contractor shall provide construction aids and imbedded items such as shown on the drawings. Fabricate forms for easy removal without hammering or prying against the concrete surfaces. Form oil may be applied to facilitate removal of forms. Forms and subbase shall be wet before placement of concrete.

C. Form Inspection: Notify the Contracting Officer 48 hours in advance of concrete placement to allow for inspection of forming and placement of items to be imbedded in the concrete. Excess water shall be removed from the forms before concrete placement.

D. Reinforcing Steel: Shall be held securely in position by spacers to keep the steel mesh in the middle of the pad vertically.

E. Rebar Anchors: Install as shown on the drawings.

F. Expansion Joints: Install expansion joints per the BLM engineer.

Install so expansion joint material is even with bottom of concrete and approximately ½” from top of concrete, and as shown on the drawings.

3.2 CONCRETE PLACEMENT

A. Mix Design: Concrete shall not be placed until the mix design has been approved by the Contracting Officer Representative.

B. Placement and Consolidation: Concrete shall be placed in lifts with a maximum depth of 6 inches. Each lift shall be adequately vibrated, rodded, or spaded into place to fill voids. Where more than one lift is placed, a vibrator shall be used to consolidate the concrete by penetrating through the upper lift and at least 6 inches into the lower lift. Vibrators shall not be used next to the form or to move concrete. Concrete shall be deposited as nearly as practical to its

03306 - 4 final position to avoid flow causing segregation of the aggregate.

Concrete shall not be dropped more than 5 feet vertically without the use of a tremie or similar device.

C. Bonding to Existing Concrete: Bonding to existing concrete shall not be allowed. Pours shall be scheduled and quantified so that each pour encompasses a complete section within expansion joints. If any pour is short, the entire section, from the last expansion joint shall be removed and re-poured.

D. Concrete Placement under Adverse Conditions: During hot weather, refer to ACI 305R. During cold weather, refer to ACI 306R. Materials required for protection shall be on the jobsite before concrete work is started. Do not place concrete on a frozen subgrade or against surfaces having deposits of frost, snow, or ice.

3.3 CONCRETE FINISHING

A. Concrete Surface Finishes:

1. Slab: Concrete slabs shall be given broom finish. Brooms shall have a minimum width of 18 inches and shall be applied perpendicular to the centerline. Edges shall be formed with a metal tool to leave a smooth border on the concrete.

B. Form Removal: Formwork not supporting concrete may be removed after curing at not less than 50 degrees F for 24 hours after placing the concrete, and when curing and protection procedures are followed as specified. The concrete should be sufficiently hard so as not to be damaged by form removal.

C. Control Joints-Pad: Shall be saw cut, with a wheel mounted saw to a depth of ¼ of the slab thickness. Saw-cutting control joints shall be completed within 24 hours after finishing concrete, but not until the concrete has cured enough to prevent aggregates from being dislodged by the saw. Saw cut locations per BLM Engineer.

D. Expansion/Control Joint Sealant: Install joint sealant at all control and expansion joints in the concrete as shown on the drawings. Clean, prime, and install backer rod within joints as instructed by the manufacturer. Note: Concrete shall have cured for 28 days prior to installing sealant as per manufacturer’s instructions.

3.4 CONCRETE CURING

A. Concrete Curing: Spray on the concrete curing compound as per manufacturing instructions.

3.5 PROTECTION

A. Requirements: During the curing period, protect concrete from load stresses, shock loads, or vibration. Do not allow vehicle’s or

03306 - 5 equipment onto concrete for a minimum of 7 days after completion of the pour.

3.6 MASONARY CLADDING

A. Have all materials for applying rock cladding on site before beginning work. Clean all surfaces to receive cladding and rock to be used as cladding.

B. Install per manufactured rock supplier instructions. Protect exposed surface from mortar.

3.7 SIGN INSTALLATION

A. Transport signs from Field Office, protect from damage during transport, storage and installation. Mount sign on base per sample photograph with appropriate hardware for sign type/weight.

PART 4: MEASUREMENT AND PAYMENT

4.1 METHOD OF MEASUREMENT

A. Units: The work described in this section will be measured and paid for by the lump sum, based on the structure and the details shown on the drawings. No extra quantity will be added for concrete placed beyond the lines and grades shown. Reinforcing steel will not be paid for separately, but is a part of the payment for Sign Construction.

4.2 BASIS OF PAYMENT

Prices and payment will be full compensation for the work described in this section. Payment will be made under:

Pay Item Pay Unit

03306(1) Portal Sign Construction LS

(Note: all signs to be within 50 miles of Field Office).

END OF SECTION