B09_Amendment0004_Attach_3_SECTION_033053_REVISED.pdf

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MISCELLANEOUS CAST--

IN-PLACE CONCRETE

SECTION 033053

MISCELLANEOUS CAST-IN-PLACE CONCRETE

PART 1 - GENERAL

1.1 RELATED DOCUMENTS

A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.

1.2 SUMMARY

A. Section includes cast-in-place concrete pavement, steps, foundations and structures including reinforcement, concrete materials, mixture design, placement procedures, and finishes.

B. Related Sections:

1. Section 312000 "Earth Moving" for fill under trail pavements.

1.3 DEFINITIONS

A. Premixed or packaged concrete: Preblended mixture of sand and/or, aggregate and cementitious materials.

B. Slip Resistance: Resistance against pedestrian slipping; defined as the ratio of a minimum tangential force necessary to initiate sliding of a pedestrian's shoe or related device over a surface.

1.4 ACTION SUBMITTALS

A. Product Data: For each type of product indicated.

B. Design Mixtures: For each concrete mixture.

C. Samples for Initial Selection: For each type of product and color.

D. Edging tool for joint details.

E. Grit Surface Fiberglass Safety Tread

1.5 INFORMATIONAL SUBMITTALS

A. Qualification Data: For qualified testing agencies.

B. Material Certificates: For the following:

1. Dry Premixed or packaged concrete.

2. Steel reinforcement and reinforcement accessories.

3. Curing compounds.

4. Bio-based form-release agent

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5. Bonding agent or epoxy adhesive

6. Emery

7. Joint fillers.

8. Repair materials.

C. Material Test Reports: For each of the following:

1. Slip Resistance static coefficient of friction for all finishes.

D. Field quality-control reports.

E. Steel Reinforcement Shop Drawings: Placing drawings that detail fabrication, bending, and placement. Include bar sizes, lengths, material, and grade, bar schedules, stirrup spacing, bent bar diagrams, bar arrangement, splices and laps, mechanical connections, tie spacing, hoop spacing, and supports for concrete reinforcement. The steel reinforcement detailer shall generate all shop drawing bending and installation details from the structural and civil drawings and specifications. The use of reproductions or photocopies of the contract drawings shall not be permitted.

1. Provide details of fabrication, bending, and placement, prepared according to ACI 315, “Details and Detailing of Concrete Reinforcement.” Include special reinforcement required for openings through concrete structures.

F. CQC (Contractor Quality Control) Accessibility Inspection Reports: Submit applicable sections of the Accessibility Inspection Report. Refer to Division 01 Section, "Quality Requirements."

1.6 QUALITY ASSURANCE

A. ACI Publications: Comply with the following, unless modified by requirements in the Contract Documents:

1. ACI 301 “Specification for Structural Concrete”

2. ACI 302.1 “Guide for Concrete Flooring and Slab Construction”

3. ACI 117, "Specifications for Tolerances for Concrete Construction and Materials."

4. ACI 309 Consolidation of Concrete

B. Testing Agency Qualifications: Qualified according to ASTM C 1077 and ASTM E 329 for testing indicated.

1. Personnel conducting field tests shall be qualified as ACI Concrete Field-Testing Technician, Grade 1, according to ACI CP-1 or an equivalent certification program.

2. When specified, Contractor shall prepare test specimens in accordance with ASTM C31, standard cylinder size 4-inch x 8 inch.

3. Testing of materials and installed work may occur at any time during progress of the work.

Rejected materials and installed work shall be removed and replaced.

C. Concrete Testing Service: Engage a qualified testing agency to perform material evaluation tests, slip resistance tests and to design concrete mixtures.

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D. Mockups: Build mockups to verify selections made under sample submittals and to demonstrate aesthetic effects and set quality standards for materials and execution.

1. Build three (3) mockups of full-thickness sections of concrete trail paving and finish, including steps, to demonstrate typical; surface finish and slip resistance, saw cut joints for slip resistant finish, texture, and color; curing; and standard of workmanship.

2. Build five (5) mockups of the colored concrete paving to show the full range of acceptable colors in the location and of the size indicated or, if not indicated, build mockups where directed by Contracting Officer (CO) and not less than 24 inches by 48 inches.

3. Contractor shall have each panel tested for slip resistance coefficient for approval by CO.

4. Approval of mockups does not constitute approval of deviations from the Contract

Documents contained in mockups unless CO specifically approves such deviations in writing.

5. Notify CO seven days in advance of dates and times when mockups will be constructed.

6. Obtain CO approval of mockups before starting construction.

7. Maintain approved mockups during construction in an undisturbed condition as a standard for judging the completed pavement.

E. Dimensions, locations, and details of equipment pads, anchors, supports, and similar features shown on the Drawings are approximate. Manufacturer's approved shop Drawings of equipment to be supported, anchored, or contained thereby shall be consulted for exact location, size, and details.

F. Preinstallation Conference: Conduct conference at Project site.

1. Review methods and procedures related to concrete paving, including but not limited to, the following:

a. Concrete mixture design.

b. Quality control of concrete materials and concrete paving construction practices.

c. Slip Resistance testing.

d. Emery finishes.

2. Require representatives of each entity directly concerned with concrete paving to attend, including the following:

a. Contractor's superintendent.

b. Independent testing agency responsible for concrete design mixtures and slip resistant testing.

c. Concrete paving subcontractor.

G. Non-Slip Resistance Testing:

1. Equipment: a “variable angle” tribometer or equal as manufactured by one of the following:

a. “US. The “Mark II” or “Mark III” tribometers by Slip-Test in Atlanta, GA (www.slip-test.com, 770-671-0090).

b. “English XL” tribometer by Excel Tribometers in Greer, SC (www.exceltribometers.com, 757-897-2853).

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2. Testing Method:

a. ASTM International test method ASTM F2508, Practice for Validation and Calibration of Walkway Tribometers Using Reference Surfaces.

1.7 PROJECT CONDITIONS

A. Traffic Control: Maintain access for vehicular and pedestrian traffic as required for other construction activities.

1.8 DELIVERY, STORAGE, AND HANDLING

A. Deliver, store, and handle steel reinforcement to prevent bending and damage.

B. Deliver, store, and handle prepackaged premixed concrete to prevent moisture absorption and damage. All materials shall be stored between 40 and 80 degrees Fahrenheit 24 hours prior to installation.

PART 2 - PRODUCTS

2.1 FORMWORK

A. Furnish formwork and formwork accessories according to ACI 301.

2.2 FORMS

A. Form Materials: Plywood, metal, metal-framed plywood, or other approved panel-type materials to provide full-depth, continuous, straight, and smooth exposed surfaces.

1. Use flexible or uniformly curved forms for curves with a radius of 100 feet or less. Do not use notched and bent forms.

B. Form-Release Agent: Bio-based form-release agent that will not bond with, stain, or adversely affect concrete surfaces and that will not impair subsequent treatments of concrete surfaces.

Concrete Release Fluids: Products that are designed to provide a lubricating barrier between the composite surface materials (concrete) and the container (forms). Provide minimum 87% bio-based content.

1. Toxicity/IEQ: Zero VOC.

C. Form Ties: Factory-fabricated, removable or snap-off metal or glass fiber-reinforced plastic form ties designed to resist lateral pressure of fresh concrete on forms and to prevent spalling of concrete on removal.

1. Furnish units that will leave no corrodible metal closer than 1 inch to the plane of exposed concrete surface.

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D. Forms cannot be washed inside the cave. Wash all forms prior to reuse outside the cave at the designated contractor storage location located near the Facility Management Office. Collect and legally dispose of all waste water and solid waste resulting from form washing.

2.3 STEEL REINFORCEMENT

A. Reinforcing Bars: ASTM A 615/A 615M, Grade 60, deformed.

B. Plain-Steel Wire: ASTM A 82/A 82M, as drawn.

C. Plain-Steel Welded Wire Reinforcement: ASTM A 185/A 185M, fabricated from as-drawn steel wire into flat sheets.

D. Deformed-Steel Welded Wire Reinforcement: ASTM A 497/A 497M, flat sheet.

E. Bar Supports: Bolsters, chairs, spacers, and other devices for spacing, supporting, and fastening reinforcing bars, welded wire reinforcement, and dowels in place. Manufacture bar supports according to CRSI's "Manual of Standard Practice" from steel wire, plastic, or precast concrete of greater compressive strength than concrete specified, and as follows:

1. Equip wire bar supports with sand plates or horizontal runners where base material will not support chair legs.

2. For concrete surfaces exposed to view where legs of wire bar support contact forms, use CRSI Class 2 stainless-steel bar supports.

2.4 CONCRETE MATERIALS

A. Comply with ASTM International - ASTM C387 Standard Specifications for Packaged, Dry, Combined Materials for Mortar and Concrete.

B. Color Pigment: ASTM C 979/C 979M, synthetic mineral-oxide pigments or colored water-reducing admixtures; color stable, free of carbon black, nonfading, and resistant to lime and other alkalis.

1. Color: As selected by CO from manufacturer's full range.

C. Water: ASTM C 94/C 94M.

2.5 RELATED MATERIALS

A. Bonding Agent: ASTM C 1059, Type II, non-redispersible, acrylic emulsion or styrene butadiene.

2.6 CURING MATERIALS

A. Absorptive Cover: AASHTO M 182, Class 3, burlap cloth or cotton mats.

B. Moisture-Retaining Cover: ASTM C 171, polyethylene film or white burlap-polyethylene sheet.

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C. Water: Potable.

2.7 CONCRETE MIXTURES

A. For all concrete work:

1. Premixed concrete with the following properties which meets or exceeds the comprehensive strengths requirements of ASTM C387:

a. Compressive Strength ASTM C39

1) (7 Days): 2500 psi.

2) (28 Days): 4000 psi.

b. Slump Limit: 2-3 inches.

c. Verify slump limits with manufacturer for slip-resistant emery applications.

2.8 FABRICATING REINFORCEMENT

A. Fabricate steel reinforcement according to CRSI’s “Manual of Standard Practice.”

2.9 CONCRETE MIXING

A. Project-Site Mixing: Measure, batch, and mix dry or prepackaged concrete materials and water in proportions according to manufacturer’s written mixing instructions. Mix concrete materials in appropriate drum-type or barrel concrete machine mixer. Final water content shall be in accordance with manufacturer’s written instructions.

2.10 SLIP RESISTIVE EMERY AGGREGATE FINISHES

A. Slip-Resistive Emery Aggregate Finish for Heavy Duty Applications: Factory-graded, packaged, rustproof, nonglazing, abrasive, crushed emery aggregate containing not less than 50 percent aluminum oxide and not less than 20 percent ferric oxide; unaffected by freezing, moisture, and cleaning materials with 100 percent passing No. 14 sieve.

1. Provide Dayton Superior; Emery Non-Slip or approved equal.

2. Color: As selected by CO from manufacturer's full range.

3. Applicable Standards:

a. 100% pure emery/corundum consisting of minimum of 58% aluminum oxide, a minimum of 24% iron oxide and no more than 4% silica

b. Moh Hardness – 8 to 9 (Diamond is a 10) Specific Gravity – 3.5

c. For heavy duty service for Class 5 and 6 industrial floors

2.11 GRIT SURFACE FIBERGLASS SAFETY TREADS

A. Thermoset polyester fiber reinforced polymer and fiber retardant Grit Surface Safety Tread with a high-traction, carbide grit surface

B. Manufactured by American Stair Treads or approved equal:

152 Rollins Avenue #102 Rockville, MD 20852 800-762-9010 240-780-3309 (fax)

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http://www.americanstairtreads.com

1. Item Number: STGSFG

a. Thickness: 1/8” thick Depth: 3” with 1" Nose.

b. Width to match stairs.

c. Federal Specs: RR-T-650E Flame Spread Rating of 75 or less using ASTM-E-84

Test

d. Color: Yellow Coarse.

e. Supply treads with two countersunk holes every 12" for screw-down installation.

PART 3 - EXECUTION

3.1 FORMWORK

A. Design, construct, erect, brace, and maintain formwork according to ACI 301.

B. Construct formwork so concrete members and structures are of size, shape, alignment, elevation, and position indicated, within tolerance limits of ACI 117.

C. Construct forms tight enough to prevent loss of concrete mortar.

D. Fabricate forms for easy removal without hammering or prying against concrete surfaces.

Provide crush or wrecking plates where stripping may damage cast concrete surfaces.

1. Install keyways, recesses, and the like, for easy removal.

E. Chamfer exterior corners and edges of permanently exposed concrete.

3.2 EXAMINATION FOR CONCRETE PAVING

A. Examine exposed subgrades and subbase surfaces to receive concrete paving for compliance with requirements for dimensional, grading, and elevation tolerances.

1. Correct subbase with unsatisfactory conditions according to requirements in

Section 312000 "Earth Moving."

2. Proceed with installation only after unsatisfactory conditions have been corrected.

3. Prepared subgrade will be inspected by the CO. Subgrade shall be approved for installation of the base course. Disturbance to subgrade caused by inspection procedures shall be repaired.

B. Preparation

1. Remove loose material from compacted subbase surface immediately before placing concrete.

3.3 EDGE FORMS AND SCREED CONSTRUCTION

A. Set, brace, and secure edge forms, bulkheads, and intermediate screed guides to required lines, grades, and elevations. Install forms to allow continuous progress of work and so forms can remain in place at least 24 hours after concrete placement.

http://www.americanstairtreads.com/

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B. Clean forms after each use and coat with form-release agent to ensure separation from concrete without damage.

3.4 EMBEDDED ITEMS

A. Place and secure anchorage devices and other embedded items required for adjoining work attached to or supported by cast-in-place concrete. Use setting drawings, templates, diagrams, instructions, and directions furnished with items to be embedded.

3.5 GRIT SURFACE FIBERGLASS SAFETY TREADS

A. Coordinate hole spacing and install treads with stainless-steel screws as per manufacturer’s instructions except for the use of adhesives or sealants which are not approved for use in the cave.

B. Clean the treads with an industrial cleaner and water.

3.6 STEEL REINFORCEMENT

A. Comply with CRSI's "Manual of Standard Practice" for fabricating, placing, and supporting reinforcement.

B. Clean reinforcement of loose rust and mill scale, earth, ice, or other bond-reducing materials.

C. Arrange, space, and securely tie bars and bar supports to hold reinforcement in position during concrete placement. Maintain minimum cover to reinforcement.

D. Set wire ties with ends directed into concrete, not toward exposed concrete surfaces.

E. In accordance with OSHA 29 CFR 1926.701 (b): Reinforcing Steel. All protruding reinforcing steel onto and into which employees or any others could fall, shall be guarded to eliminate the hazard of impalement.

3.7 JOINTS

A. General: Construct joints true to line with faces perpendicular to surface plane of concrete.

B. Construction Joints: Locate and install so strength and appearance of concrete are not impaired, at locations indicated or as approved by CO.

C. Isolation Joints: Install joint-filler strips at junctions with trail paving-on-grade and vertical surfaces, such as column pedestals, foundation walls, grade beams, and other locations, as indicated.

1. Extend joint fillers full width and depth of joint, terminating flush with finished concrete surface, unless otherwise indicated.

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3.8 CONCRETE PLACEMENT

A. Comply with ACI 301 for placing concrete.

B. Before test sampling and placing concrete, water may be added at Project site, subject to limitations of ACI 301.

C. Do not add water to concrete during delivery. Do not add water to fresh concrete after testing.

Do not add water to concrete after adding high-range water-reducing admixtures to mix.

D. Before placing concrete, inspect and complete formwork installation, steel reinforcement, and items to be embedded or cast-in.

E. Deposit concrete continuously in one layer or in horizontal layers of such thickness that no new concrete will be placed on concrete that has hardened enough to cause seams or planes of weakness. If a section cannot be placed continuously, provide construction joints as indicated.

Deposit concrete to avoid segregation.

F. Consolidate concrete with mechanical vibrating equipment.

3.9 FOR CONCRETE PAVING:

A. Before placing concrete, inspect and complete formwork installation, steel reinforcement, and items to be embedded or cast-in.

B. Moisten subbase to provide a uniform dampened condition at time concrete is placed. Do not place concrete around other structures until they are at required finish elevation and alignment.

C. Deposit and spread concrete in a continuous operation between transverse joints. Do not push or drag concrete into place or use vibrators to move concrete into place.

D. Consolidate concrete according to ACI 301 by mechanical vibrating equipment supplemented by hand spading, rodding, or tamping.

1. Consolidate concrete along face of forms and adjacent to transverse joints with an internal vibrator. Keep vibrator away from joint assemblies, reinforcement, or side forms. Use only square-faced shovels for hand spreading and consolidation. Consolidate with care to prevent dislocating reinforcement and joint devices.

E. Screed paving surface with a straightedge and strike off.

F. Commence initial floating using bull floats or darbies to impart an open-textured and uniform surface plane before excess moisture or bleed water appears on the surface. Do not further disturb concrete surfaces before beginning finishing operations or spreading surface treatments.

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3.10 FINISHING FORMED SURFACES

A. Rough-Formed Finish: As-cast concrete texture imparted by form-facing material with tie holes and defective areas repaired and patched. Remove fins and other projections exceeding 1/2 inch.

1. Apply to concrete surfaces not exposed to public view.

B. Smooth-Formed Finish: As-cast concrete texture imparted by form-facing material, arranged in an orderly and symmetrical manner with a minimum of seams. Repair and patch tie holes and defective areas. Remove fins and other projections exceeding 1/8 inch.

C. Related Unformed Surfaces: At tops of walls, horizontal offsets, and similar unformed surfaces adjacent to formed surfaces, strike off smooth and finish with a texture matching adjacent formed surfaces. Continue final surface treatment of formed surfaces uniformly across adjacent unformed surfaces, unless otherwise indicated.

3.11 CONCRETE PAVING FINISHING

A. General: Comply with ACI 302.1R for screeding, restraightening, and finishing operations for concrete surfaces. Do not wet concrete surfaces.

B. Float Finish: Begin the second floating operation when bleed-water sheen has disappeared, and concrete surface has stiffened sufficiently to permit operations. Float surface with power-driven floats or by hand floating if area is small or inaccessible to power units. Finish surfaces to true planes. Cut down high spots and fill low spots. Refloat surface immediately to uniform granular texture.

1. Apply a nonslip broom finish to surfaces indicated and to exterior concrete paving, steps, and ramps. Broom Finish: Provide a course finish by striating float-finished concrete surface 1/16 to 1/8-inch deep with a stiff-bristled broom, perpendicular to line of traffic.

2. Slip Resistance: Minimum value as follows, based on testing according International test method ASTM F2508: static coefficient of friction 0.7.

3.12 EMERY SLIP RESISTIVE FINISH

A. Prepare main slabs as recommended by manufacturer. Prime surface using primer or bonding agent type and application methods recommended by primer and topping material manufacturer(s).

B. Mix and apply topping material following manufacturer's directions at a minimum of 0.6 lbs.

per square foot.

C. Screed topping material to level and thickness indicated. Finish trowel to achieve surface finish indicated. Immediately cure slab using one of more approved curing methods.

D. Placement:

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1. Placement of Base Concrete: Only place when ambient temperature is between 40°– 90°F. Admixtures containing calcium chloride should not be used. Superplasticizers (high range water reducers) should be avoided, if possible.

2. Placement of Non-Slip Aggregate:

a. For heavy duty applications, first prepare a dry mix of 4 parts by weight of Emery

Non-Slip and 1-part portland cement. Apply at rates recommended by manufacturer. Do not broadcast Emery Non-Slip directly into bleed water. Apply Emery Non-Slip uniformly and avoid concentration or piling up of the emery.

Broadcast by hand, or a Morrison Spreader. (A mechanical spreader will give the most uniform results and a Morrison Spreader or equal is recommended). If Emery Non-Slip is distributed by hand, avoid separation of fines and granular material.

b. Avoid clumping material on the surface. Allow the Emery Non-Slip to remain unworked on the surface and allow it to wet out until it has darkened and is uniform in color; Emery Non-Slip will darken as it absorbs bleed water. Then float the surface by hand with wood floats or power float to embed and integrate the Emery Non-Slip into the concrete surface as well as remove any surface irregularities. To prevent closing the slab too early, do not steel trowel or use combination blades. Leave part of the non-slip aggregate exposed for the non-slip surface profile. Early setting around the slab edges will occur and should be monitored closely to properly time the floating operation. Immediately apply the remaining 1/3 amount of Emery Non-Slip uniformly at right angles to the first application. The second application does not have to be applied at right angles to the first application if a mechanical spreader is used. After the Emery Non-Slip has absorbed water and the concrete is firm, then trowel leaving part of the aggregate exposed to achieve the desired finish and texture. Do not rewet and do not overwork. Prevent closing the slab too early as blistering or delamination may occur. Do not use combination blades.

E. Clean Up

1. Use clean water. Clean all tools and equipment before Emery Non-Slip has set.

F. Curing

1. Immediately after final finishing, and after the surface water has disappeared, apply a

Dayton Superior membrane forming curing compound or cure and seal. Wet curing methods compliant with ACI 308 may also be employed.

G. Waste Disposal

1. Dispose of waste material and empty packaging in accordance with all Federal, State and

Local requirements.

3.13 CONCRETE PROTECTING AND CURING

A. General: Protect freshly placed concrete from premature drying and excessive cold or hot temperatures. Comply with ACI 306.1 for cold-weather protection and with ACI 301 for hot-weather protection during curing.

B. Begin curing after finishing concrete but not before free water has disappeared from concrete surface.

H ar de ne rs /In du st ria l T op pi ng s

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C. Curing Methods: Cure formed and unformed concrete for at least seven days in accordance with manufacturer’s written instructions.

3.14 ACCESSIBILITY INSPECTIONS

A. Perform pre-installation accessibility inspection: Concerning formwork, and preliminary site work and grading tasks, check to ensure construction tolerances or margins are sufficient to ensure compliance of completed work. Ensure that grades and slopes adhere to DSC Accessible Route Design Standards. Ensure that embedded items are properly placed, including reinforcement work and anchors. Ensure that obstructions are treated in advance of commencing next stage. Report any inconsistencies to CO and submit Report within 24 hours of commencing inspection. Cover and protect work in progress if necessary to protect work until CO can review/approve findings. Correct errors or deficiencies before proceeding with second stage - installation of slabs, flush bands, or other finished materials/items.

B. Perform post-installation accessibility inspection: Immediately upon completion, and when curing will permit examination, record observations and cite non-compliance with ABAAS.

Supplement report with digital images, notes, sketches, red-line drawings, survey data, product literature or miscellaneous items explaining completed work. Submit report within 24 hours of commencing inspection to CO.

3.15 PAVING TOLERANCES

A. Comply with tolerances in ACI 117 and ABAAS as follows:

1. Elevation: 1/4 inch.

2. Thickness: Plus 3/8 inch, minus 1/4 inch.

3. Surface: Gap below 10-foot- long, unleveled straightedge not to exceed 1/8 inch

4. Joint width: 3/8” inch, plus 1/8”, no minus.

3.16 FIELD QUALITY CONTROL

A. Testing required determining compliance for the work of this section will be the responsibility of the Contractor, at no additional expense to the Government.

B. Testing Services: Testing of composite samples of fresh concrete obtained according to ASTM C 172 shall be performed according to the following requirements:

1. Testing Frequency: Obtain at least one composite sample for each 5000 sq. ft. or fraction thereof of each concrete mixture placed each day.

a. When frequency of testing will provide fewer than five compressive-strength tests for each concrete mixture, testing shall be conducted from at least five randomly selected batches or from each batch if fewer than five are used.

2. Slump: ASTM C 143/C 143M; one test at point of placement for each composite sample, but not less than one test for each day's pour of each concrete mixture. Perform additional tests when concrete consistency appears to change.

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3. Compression Test Specimens: ASTM C 31/C 31M; cast and laboratory cure one set of three standard cylinder specimens for each composite sample.

4. Compressive-Strength Tests: ASTM C 39/C 39M; test one specimen at seven days and two specimens at 28 days.

a. A compressive-strength test shall be the average compressive strength from two specimens obtained from same composite sample and tested at 28 days.

C. Strength of each concrete mixture will be satisfactory if average of any three-consecutive compressive-strength tests equals or exceeds specified compressive strength and no compressive-strength test value falls below specified compressive strength by more than 500 psi.

D. Test results shall be reported in writing to CO, concrete manufacturer, and Contractor within 48 hours of testing. Reports of compressive-strength tests shall contain Project identification name and number, date of concrete placement, name of concrete testing and inspecting agency, location of concrete batch in Work, design compressive strength at 28 days, concrete mixture proportions and materials, compressive breaking strength, and type of break for both 7- and 28-day tests.

E. Nondestructive Testing: Impact hammer, sonoscope, or other nondestructive device may be permitted by CO but will not be used as sole basis for approval or rejection of concrete.

F. Additional Tests: Testing and inspecting agency shall make additional tests of concrete when test results indicate that slump, air entrainment, compressive strengths, or other requirements have not been met, as directed by CO.

G. Concrete paving will be considered defective if it does not pass tests and inspections.

H. Additional testing and inspecting, at Contractor's expense, will be performed to determine compliance of replaced or additional work with specified requirements.

I. Prepare test and inspection reports.

3.17 REPAIRS AND PROTECTION

A. Remove and replace concrete paving that is broken, damaged, or defective or that does not comply with requirements in this Section. Remove work in complete sections from joint to joint unless otherwise approved by CO.

B. Drill test cores, where directed by CO, when necessary to determine magnitude of cracks or defective areas. Fill drilled core holes in satisfactory paving areas with portland cement concrete bonded to paving with epoxy adhesive.

C. Protect concrete paving from damage. Exclude traffic from paving for at least 14 days after placement. When construction traffic is permitted, maintain paving as clean as possible by removing surface stains and spillage of materials as they occur.

D. Maintain concrete paving free of stains, discoloration, dirt, and other foreign material. Sweep paving not more than two days before date scheduled for Substantial Completion inspections.

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E. Remove and replace concrete and emery slip resistant finishes that do not comply with requirements in this Section.

END OF SECTION 033053