SOW.pdf

TECHNICAL SPECIFICATIONS

Concrete Slab On Grade at the

Rachel Carson NWR

Maine

TABLE OF CONTENTS

SECTION TITLE

DIVISION 1 - GENERAL REQUIREMENTS

01010 Summary of Work

01300 Submittals

DIVISION 2 - SITE WORK

02200 Excavation, Backfilling, and

Site Grading

03300 Concrete

SECTION 01010

SUMMARY OF WORK

1.01 DESCRIPTION OF WORK

1. The work to be accomplished under this contract consists of the construction of a concrete slab on grade for a future storage building, to be constructed by the Government at a later date.

The proposed location for the concrete slab will be staked in the field by the on site Government representative as shown in the picture in the Appendix to this document. Some concrete slab details are also shown in the Appendix.

2. Contractor shall furnish all labor, materials, equipment and incidentals necessary to complete the work in accordance with these specifications and as shown on sketches in the Appendix.

1.02 LOCATION AND INSPECTION OF SITE

A. Prospective bidders should visit the site of the work area.

1.03 FACILITY OPERATIONS

Rachel Carson NWR will continue operations during the performance of the contract.

The Contractor shall confine their operations to weekdays, Monday thru Friday (holidays excluded), between the hours of

7:30 a.m. to 4:00 p.m., unless prior approval is given by the

Facility Manager.

The Contractor shall exercise care and shall perform required work diligently. If it becomes necessary to interrupt any function of the facility, the Contractor shall notify the

Manager and shall not proceed with such interruptions until such time as the Refuge Manager makes provision for, and approves such operations.

The contractor shall notify the Manager 24 hours prior to the delivery of any materials, and 48 hours prior to the beginning of each item of work that is scheduled to take place.

1.04 ACCESS

A. In the performance of work for this contract, any existing sections of facility roads shall be returned to their original condition prior to contractor operations.

The contractor shall exercise care to minimize deterioration of these existing roadways.

1.05 SAFETY

All work shall be performed in a safe manner per Department of

Labor's Occupational Safety and Health Administration (29 CFR

Part 1926) and any applicable USFWS Safety and Health

Regulations.

1.06 CLEANUP

A. The Contractor shall clean up and dispose of daily, all rubbish and waste accumulation.

B. The Contractor shall, at completion of the project, remove tools and equipment, and leave the premises clean.

END OF SECTION

SECTION 01300

SUBMITTALS

1.01 GENERAL

Prior to the start of work, the Contractor shall submit the following required information.

1.02 CERTIFICATION

Certificates required: as applicable

Gravel materials

Concrete mix design

1.03 MATERIALS

Submit manufacturer’s information for rebar and welded wire fabric materials.

SECTION 02200

EXCAVATION, BACKFILLING & SITE GRADING

PART 1 - GENERAL

1.01 DESCRIPTION OF WORK

A. The work of this section consists of the excavation and backfilling required for the concrete slab installation.

1.02 SAFETY

A. Protect all known existing utilities against damage.

B. Barricades, warning lights, and similar safety precautions shall be provided as required.

1.03 WASTE

A. Excavated material not suitable by the government for fill requirements and excess material, shall be removed per approval of the government from the site, by the Contractor. Disposal receipt(s) are required.

PART 2 - PRODUCTS

2.01 MATERIALS to be approved prior to use

A. IMPORTED GRAVEL: Clean local or commercial material consisting of natural or artificial mixtures of natural or manufactured gravels, stone, slag, or sand; free of soil, muck, roots, vegetative and organic matter and debris.

Gravel materials must also meet the gradation and requirements of the latest edition of the Maine Department of Transportation

Specifications, Section 703, Aggregates.

Gradation Requirements for gravel materials:

Sieve Size % passing

0.25 inch 25-70

No. 40 0-30

No. 200 0-7

PART 3 - EXECUTION

3.01 STRIPPING

The existing surface shall be stripped from the areas where the concrete slab on grade is to be constructed, and shall be stockpiled at a location approved by the Government, to be retained by the Government for their future use.

3.02 EXCAVATION

A. Excavation for concrete slab shall be carried below grade as required for construction. If excavations are carried below the required depth without written authorization, they shall be backfilled with fill concrete at the Contractor's expense.

If there are areas of subgrade which are unsuitable due to highly organic matter, trash or debris, this unsound material shall be removed to an additional depth not to exceed one feet, and backfilled with imported gravel material free from organic material, trash or debris.

B. Stripping of existing gravel ground cover and subgrade excavation, with allowance for 12 inches of gravel layer, shall be performed in areas where the gravel layer is to be placed. If unsuitable subgrade material is found in some areas, then excavate to an additional depth not to exceed one feet to suitable material and backfill with gravel fill material.

3.03 BACKFILL

A. Gravel base shall be placed in 6 inch layers and compacted to

95% of maximum density at optimum moisture content by hand or mechanical tampers.

B. Fill around concrete area shall be placed in layers not to exceed 12 inches, and compacted by hand or mechanical tampers to

90% of maximum density at optimum moisture content.

3.04 SITE GRADING

A. Respread stockpiled topsoil. Grading shall produce a finished surface that is free from depressions and which will provide drainage and prevent pocketing of water.

SECTION 03300

CONCRETE

PART 1 - GENERAL

1.01 SECTION INCLUDES

A. Cast in place concrete required for slab on grade.

1.02 REFERENCES

A. ASTM C33 - Concrete Aggregate.

B. ASTM C94 - Ready-Mixed Concrete.

C. ASTM C150 - Portland Cement.

D. ASTM C260 - Air Entraining Admixtures for Concrete.

1.03 QUALITY ASSURANCE

A. Perform cast-in-place concrete work in accordance with ACI

301 and as specified herein.

1.04 SUBMITTALS

A. Furnish certification that concrete mix meets specified requirements. Provide items of information as specified under

ASTM C94, batch ticket information.

1.05 JOB CONDITIONS

A. Weather Conditions: ACI 305 and 306, Hot and Cold Weather

Concreting.

B. Place no concrete on mud, disturbed soil, or frozen surfaces.

C. Maintain site in dry condition during placing and curing operations.

PART 2 - PRODUCTS

2.01 FORMS

A. Conform to ACI 301.

B. Lumber, steel, or other approved material.

C. Premolded joint filler shall be bituminous fiber type, complying with ASTM D-1752.

2.02 CONCRETE MATERIALS

A. Cement: ASTM C150, Type II cement with air-entraining admixture.

B. Aggregates

1. Fine: ASTM C33; natural sand.

2. Course: ASTM C33; crushed stone or gravel, maximum size of course aggregate shall be one inch.

C. Water: Clean and free from deleterious amount of acids, alkalis and organic materials.

2.03 ADMIXTURES

A. Air Entrainment Admixture: ASTM C260.

2.04 CONCRETE MIX

A. ACI 301; Compressive Strength, 28 days, 4000 psi; slump, minimum of two inch, maximum four inches; air entrainment 5-1/2 percent, plus or minute 1-1/2 percent, water-cement ratio shall not exceed 0.45, inclusive of water in the aggregate.

B. Mix concrete and admixtures in accordance with ASTM C94.

C. Addition of water to the mix at the project site must be approved by the Engineer and maximum water/cement ratio shall not be exceeded. The delivery ticket shall be noted with amount of additional water added and submitted to the Engineer.

D. Concrete shall be discharged at the job within one hour after water has been added to the cement and aggregates or cement batched with aggregates.

2.05 REINFORCING STEEL AND STEEL ITEMS

A. Reinforcing steel shall be welded wire fabric, conforming to

ASTM A 185, flat sheets, uncoated finish.

B. Rebar shall be ASTM grade 60 bars.

PART 3 - EXECUTION

3.01 FORMWORK ERECTION

A. Install formwork to confine the concrete to be placed.

B. Hand trim sides and bottom of earth forms; remove loose soil.

C. Brace, and support formwork to prevent lateral movement.

D. Provide chairs, and/or supports as required to insure that welded wire fabric will be located at mid depth within the slab.

3.02 PLACING CONCRETE

A. Comply with ACI 301.

B. Concrete shall be well vibrated, rodded or spaded into place to fill all voids and angles to insure dense concrete without voids.

C. Water shall be removed from within forms and excavations before and during placement of concrete.

3.03 REMOVAL OF FORMS AND CURING

A. Formwork may be removed after cumulatively curing at not less than 50 degrees F for 72 hours after placing concrete provided concrete is sufficiently hard and not damaged by form removal operations and provided that curing and protection operations are maintained.

B. Concrete surface shall be protected from loss of moisture by one of the following materials:

1. Burlap cloth made from jute or kenaf, kept moist.

2. Moisture retaining cover, such as polyethlene film.

3. Application of a curing compound, ASTM C309, Type 1, clear liquid, membrane forming. Rate of application is 2 coats, 200 square feet per gallon per coat.

3.04 PROTECTION

A. Immediately after placement, protect concrete from premature drying, excessive hot or cold temperatures, and mechanical injury.

3.05 FINISH

Top surface of concrete shall be broom finished. Sawcut crack control joints at 15’ on center maximum each way, within 8 hours after initial concrete placement.

APPENDIX

Proposed location for the concrete slab and some sketches of the concrete slab on grade

The proposed location for the concrete slab will be staked in the field by the on site Government representative at the northern part of the open field near the tree line.