SECTION UNIT PAVERS

Size: px
Start display at page:

Download "SECTION UNIT PAVERS"

Transcription

1 PART 1 - GENERAL 1.1 SUMMARY A. Section includes the following: 1. Concrete pavers. 2. Detectable warning pavers. 3. Warning stripe pavers. 1.2 SUBMITTALS A. Product Data: For the following: 1. Pavers. 2. Include test result from an independent testing laboratory for compliance of paving unit requirements to ASTM C 936. B. Shop Drawings: Indicate layout, pattern, and relationship of paving joints to project formed details. C. Sieve Analyses: In accordance with ASTM C 136 for grading of bedding and joint sand. D. Samples for Verification: 1. Full-size units of each type of unit paver indicated. 1.3 QUALITY ASSURANCE A. Source Limitations: Obtain each type of unit paver, joint material, and setting material from single source with resources to provide materials and products of consistent quality in appearance and physical properties. B. Mockups: Build mockups to verify selections made under Sample submittals and to demonstrate aesthetic effects and set quality standards for materials and execution. 1. Provide a mockup for each Station location. Mockup shall include the following: a. Concrete pavers. b. Detectable warning pavers. c. Warning stripe pavers. 2. Mockup location is Contractor s option; mockup size shall be not less than 10-feet square and shall include a full layout of the Warning Stripe Paver. Page 1 of 7

2 3. Approved mockups may become part of the completed Work if undisturbed at time of Final Acceptance. C. Preinstallation Conference: Conduct conference at Project site. 1.4 DELIVERY, STORAGE, AND HANDLING A. Store pavers on elevated platforms in a dry location. If units are not stored in an enclosed location, cover tops and sides of stacks with waterproof sheeting, securely tied. PART 2 - PRODUCTS 2.1 MATERIALS A. Concrete Pavers: Solid paving units complying with ASTM C Pavers shall have the following characteristics: a. Average Compressive Strength: 8,000 psi with no individual unit under 7200 psi. b. Average Water Absorption: 5% with no unit greater than 7% when tested in accordance with ASTM C140. c. Color Pigment Material Standard: Comply with ASTM C979 d. Thickness: 2-3/8 inches. e. Face Size: Refer to the Material Schedules in the Plans. f. Color: To match Engineer s sample. Refer to Materials Schedules in the Plans. B. Detectable Warning Pavers: Solid paving units complying with ASTM C 902 and in accordance with 2010 ADA Standards for Accessible Design, Title II, Chapter 7, Section 705 DETECTABLE WARNINGS. 1. Pavers shall have the following characteristics: a. Average Compressive Strength: Greater than or equal to 8,000 psi; ASTM C140. b. Flexural Strength: Greater than or equal to 700 psi; ASTM C973 c. Average Water Absorption: Less than 5%; ASTM C140. d. Color Pigment Material Standard: Comply with ASTM C979 e. Thickness: 2-1/2 inches nominal. f. Paver Size: 2-0 x 4-0. g. Color: Federal Yellow to match Engineer s sample. Refer to Materials Schedules in the Plans. C. Warning Stripe Pavers: Solid paving units complying with ASTM C Pavers shall have the following characteristics: a. Average Compressive Strength: Greater than or equal to 8,000 psi; ASTM C140. b. Flexural Strength: Greater than or equal to 700 psi; ASTM C973 c. Average Water Absorption: Less than 5%; ASTM C140. d. Color Pigment Material Standard: Comply with ASTM C979 e. Thickness: 2 inches nominal. f. Paver Size: 6 x 12 Page 2 of 7

3 g. Color: Stained A-40 Federal Yellow to match Engineer s sample. h. Epoxy Lettering: Epoxy resin filled engraved lettering. 1) Lettering Message: STAND BEHIND YELLOW LINE 2) Sandblast Engraving Depth: 1/4-inch. 3) Epoxy Resin Color: Black to match Engineer s sample. 2.2 AGGREGATE SETTING-BED MATERIALS A. Bedding Sand: Sound, sharp, washed, natural sand or crushed rock complying with gradation requirements in ASTM C 33 with 100 percent passing 3/8 inch sieve and no more than 10 percent passing No. 100 sieve. B. Joint Sand: Fine, sharp, washed, natural sand with 100 percent passing No. 4 sieve and no more than 15 percent passing No. 100 sieve. 1. Provide colored sand to match pavers. Submit sample to Engineer for approval. C. Do not use limestone screenings, stone dust, or sand for the bedding sand material that do not conform to the grading requirements of ASTM C 33. D. Do not use mason sand or sand conforming to ASTM C 144 for the bedding sand. 2.3 MORTAR SETTING-BED MATERIALS A. Thin-Set Mortar for Bond Coat: Latex-portland cement mortar complying with ANSI A Provide prepackaged, dry-mortar mix containing dry, redispersible, vinyl acetate or acrylic additive to which only water must be added at Project site. B. Water: Potable. C. Grout: Exterior based grout; color to be selected by the Engineer from manufacturer s full line. 1. Performance Requirements: a. Classification Code: CG2 (cementitious grout, improved), W (reduced water absorption), A (high abrasion resistance), F (rapid-setting); ISO b. Compression: 3,500 to 5,500 psi at 28 days; ANSIA c. Compressive Strength: 5,500 psi at 28 days. d. Shrinkage: Less than 0.10 (7 days); ANSI A e. Water Absorption: Less than 7% (immersion to dry); ANSI A Page 3 of 7

4 2.4 ACCESSORIES A. Sealer: Matte-finish penetrating protective sealer. 1. Products and Manufacturers: Provide the following or an approved equal: a. Sealer shall have the following characteristics: 1) Penetrating sealer. 2) Solvent based. 3) Matte-finish. 4) Oil repellent. 5) Non-film-forming. B. Pea Gravel: Well-graded, washed gravel, 1/8 to 1/4 inch diameter size. C. Geotextile (Drainage Fabric): 1. Geotextile shall have the following characteristics: a. Nonwoven needle-punched geotextile fabric, manufactured for subsurface drainage applications, made from polypropylene, polyolefins, or polyesters; with elongation greater than 50 percent; complying with AASHTO M 288 and the following, measured per test methods referenced: 1) Tensile Strength: 90 lbs; ASTM D ) Apparent Opening Size: 50 US sieve, maximum; ASTM D ) Permittivity: 2.00 Sec-1; ASTM D ) Water Flow Rate: 150 gallons/minute/square foot; ASTM D MORTAR AND GROUT MIXES A. General: Comply with referenced standards and with manufacturers' written instructions for mix proportions, mixing equipment, mixer speeds, mixing containers, mixing times, and other procedures needed to produce setting-bed and joint materials of uniform quality and with optimal performance characteristics. Discard mortars and grout if they have reached their initial set before being used. B. Thinset Mortar Bond Coat: Proportion and mix according to manufacturer's written instructions. C. Packaged Grout: Proportion and mix according to grout manufacturer's written instructions. PART 3 - EXECUTION 3.1 EXAMINATION A. Examine areas indicated to receive paving, with Installer present, for compliance with requirements for installation tolerances and other conditions affecting performance. Page 4 of 7

5 B. Where pavers are to be installed over waterproofing, examine waterproofing installation, with waterproofing Installer present, for protection from paving operations, including areas where waterproofing system is turned up or flashed against vertical surfaces. C. Proceed with installation only after unsatisfactory conditions have been corrected. 3.2 PREPARATION A. Sweep concrete substrates to remove dirt, dust, debris, and loose particles. 3.3 INSTALLATION, GENERAL A. Do not use unit pavers with chips, cracks, voids, discolorations, or other defects that might be visible or cause staining in finished work. B. Mix pavers from several pallets or cubes, as they are placed, to produce uniform blend of colors and textures. C. Cut unit pavers with motor-driven masonry saw equipment to provide clean, sharp, unchipped edges. Cut units to provide pattern indicated and to fit adjoining work neatly. Use full units without cutting where possible. Hammer cutting is not acceptable. D. Joint Pattern: As indicated on Plans. E. Tolerances: Do not exceed 1/32-inch unit-to-unit offset from flush (lippage) nor 1/8 inch in 10 feet from level, or indicated slope, for finished surface of paving. 3.4 AGGREGATE SETTING-BED APPLICATIONS A. Spread bedding sand evenly and screed to a nominal 1 in. thickness. B. Set pavers in patterns shown with a minimum joint width of 1/16 inch and a maximum of 1/8 inch, being careful not to disturb leveling base. If pavers have spacer bars, place pavers hand tight against spacer bars. Use string lines to keep straight lines. C. Spread dry sand and fill joints immediately after vibrating pavers into bedding sand. Vibrate pavers and add sand until joints are completely filled, then remove excess sand. Leave a slight surplus of sand on the surface for joint filling and to protect pavers from damage. Remove excess sand at time of Final Completion. D. Broom clean surface after removal of excess joint sand. E. Do not allow traffic on installed pavers until sand has been vibrated into joints. F. Repeat joint-filling process 30 days later, or as allowed by the Engineer, and reseal. Page 5 of 7

6 3.5 MORTAR SETTING-BED APPLICATIONS A. Apply mortar-bed bond coat over surface of concrete subbase about 15 minutes before placing mortar bed. Do not exceed 1/16-inch thickness for bond coat. Limit area of bond coat to avoid its drying out before placing setting bed. B. Wet brick pavers before laying if the initial rate of absorption exceeds 30 g/30 sq. in. per minute when tested according to ASTM C 67. Allow units to absorb water so they are damp but not wet at time of laying. C. Set pavers using methods to obtain full contact with setting bed and to bring finished surfaces within indicated tolerances. Set each paver in a single operation before initial set of mortar; do not return to areas already set or disturb pavers for purposes of realigning finished surfaces or adjusting joints. D. Spaced Joint Widths: Provide 3/8-inch nominal joint width with variations not exceeding plus or minus 1/16 inch. E. Grouted Joints: Grout paver joints complying with ANSI A F. Grout joints as soon as possible after initial set of setting bed. 1. Force grout into joints, taking care not to smear grout on adjoining surfaces. 2. Clean pavers as grouting progresses by dry brushing or rubbing with dry burlap to remove smears before tooling joints. 3. Tool exposed joints slightly concave when thumbprint hard, using a jointer larger than joint thickness unless otherwise indicated. 4. If tooling squeezes grout from joints, remove excess grout and smears by dry brushing or rubbing with dry burlap and tool joints again to produce a uniform appearance. G. Cure grout by maintaining in a damp condition for seven days unless otherwise recommended by grout or liquid-latex manufacturer. 3.6 APPLICATION OF SEALER A. General: Comply with manufacturer s instructions and recommendations and as follows: 1. Application Rate: Apply one coat at a rate of square feet per gallon. 3.7 REPAIRING, POINTING, AND CLEANING A. Remove and replace unit pavers that are loose, chipped, broken, stained, or otherwise damaged or that do not match adjoining units. Provide new units to match adjoining units and install in same manner as original units, with same joint treatment and with no evidence of replacement. B. Pointing: During tooling of joints, enlarge voids or holes and completely fill with grout. Point joints at sealant joints to provide a neat, uniform appearance, properly prepared for sealant application. C. Cleaning: Remove excess grout from exposed paver surfaces; wash and scrub clean. Page 6 of 7

7 3.8 FIELD QUALITY CONTROL A. The final surface tolerance from grade elevations shall not deviate more than ± 1/8 in. under a 10 ft straightedge. B. Check final surface elevations for conformance to plans. 3.9 PROTECTION A. Protect work from damage due to subsequent construction activities until time of Final Completion and acceptance of the work. END OF Page 7 of 7