REINFORCED CONCRETE MASONRY SECTION

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1 SECTION REINFORCED CONCRETE MASONRY PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of Contract, including General and Supplementary Conditions and Division 01 Specification sections, apply to work of this section. 1.2 DESCRIPTION A. Work under this section includes furnishing and placing masonry units, reinforcing, grout, mortar, bond beams and connectors. Furnishing and installing bracing, forming, scaffolding, shoring, and other equipment for constructing masonry. B. Work installed but furnished under other sections of these Specifications: Built-in loose lintels and anchors as detailed. 1.3 QUALITY ASSURANCE A. Provide certificates that materials comply with respective ASTM requirements. Comply with the following codes and provisions: 1. ACI 530/ASCE 5/TMS 402 "Building Code Requirements for Masonry Structures". 2. ACI 530.1/ASCE 6/TMS 602 "Specifications for Masonry Structures" 3. ACI 315 "Details and Detailing of Concrete Reinforcement" 4. ASTM A 82 "Standard Specification for Steel Wire, Plain, for Concrete Reinforcement" 5. ASTM A 153 "Standard Specification for Zinc Coated (Hot Dip) on Iron and Steel Hardware" 6. ASTM A 615 "Standard Specification for Deformed and Plain Billet-Steel Bars for Concrete Reinforcement" 7. ASTM C 90 "Standard Specification for Hollow Load-Bearing Concrete Masonry Units" 8. ASTM C 109 "Standard Test Method for Compressive Strength of Hydraulic Cement Mortars" 9. ASTM C 140 "Standard Method of Sampling and Testing Concrete Masonry Units" 10. ASTM C l44 "Aggregate for Masonry Mortar" 11. ASTM C 150 "Standard Specification for Portland Cement" 12. ASTM C 207 "Standard Specification for Hydrated Lime for Masonry Purposes" 13. ASTM C 270 "Standard Specification for Mortar for Unit Masonry" 14. ASTM C 404 "Aggregate for Masonry Grout" 15. ASTM C 476 "Standard Specification for Grout for Reinforced and Non-reinforced Masonry" 16. ASTM C 780 "Method for Preconstruction and Construction Evaluation of Mortars for Plain and Reinforced Unit Masonry" 17. ASTM C 1019 "Standard Method of Sampling and Testing Grout" 1.4 SUBMITTALS REINFORCED CONCRETE MASONRY SECTION

2 A. Submit shop drawings for fabrication, bending and placement of reinforcing bars. Show wall elevations including placement and lapping of all vertical and horizontal reinforcing, including bond beams and lintels. Include list of bar support accessories provided. B. Certified Mill Test Reports shall be sent directly to the Architect in triplicate or electronically. C. Submit test reports for concrete block units verifying compliance with specification requirements. D. Submit mix design test reports in accordance with ASTM C 1019 for grout to be used. E. Submit verification that mortar to be used is in accordance with ASTM C Proportion Specification. 1.5 ENVIRONMENTAL CONDITIONS A. Masonry shall be covered with plastic or canvas at the end of the every work day to prevent water from entering the masonry. B. Cold Weather 1. When the ambient air temperature falls below 40 degrees F or the temperature of the masonry block units falls below 40 degrees F the following precautions shall be implemented: a. Heat mortar and mixing water to produce mortar temperatures between 40 and 120 degrees F. 2. When daily average temperatures are between 32 and 40 degrees F, protect completed masonry from rain or snow by covering with a weather resistive membrane for at least 48 hours after construction. 3. When temperature is between 32 and 20 degrees F, provide wind breaks on both sides of the masonry. Also, completely cover masonry with insulating blankets for 48 hours after construction. Heat grout to a temperature of at least 70 degrees F. 4. When ambient temperatures fall below 20 degrees F, provide a heated enclosure to maintain a temperature of above 32 degrees F. Maintain masonry at a temperature above 36 degrees F for at least 48 hours. Heat grout to a temperature of at least 70 degrees F. C. Hot Weather 1. When temperature exceeds 95 degrees F set masonry units within one minute of spreading mortar. D. Product Handling 1. Deliver and handle materials to prevent damage. Store all masonry materials above ground to prevent absorption of moisture, staining, and exposure to the weather. PART 2 - PRODUCTS 2.1 MATERIALS REINFORCED CONCRETE MASONRY SECTION

3 A. Normal weight (125 PCF Min.) and lightweight (105 PCF Max.) load bearing concrete masonry units: 1. Conform to ASTM C55 for solid load bearing masonry units. 2. Conform to ASTM C90 for hollow load bearing masonry units. 3. Units shall be nominal l6 inches long, 8 inches high by width as required. 4. Provide all necessary lintel blocks, corner blocks, concrete brick, bond beams, sash blocks and other shapes required to complete the work. Exposed edges shall be "bullnosed". 5. Expose faces of units shall be free of cracks, chips and other defects. 6. Minimum compressive strength shall be 2,800 psi on the net area. B. METAL REINFORCEMENT ANCHORS: 1. Adjustable anchors (for cavity walls):.188" diameter pintle sections, hot dip galvanized, ASTM A153, Class B2 (1.5 oz), to be used with eye sections welded to joint reinforcement. 2. Horizontal reinforcement: conform to ASTM A-82 with galvanizing conforming to ASTM A 153, Class B2, two inches less than the nominal width of wall, equal to: Dur-O- Wall Products, or equal, truss or ladder joint reinforcement (see drawings for type required). Side wires shall be.188" diameter (unless noted otherwise). Cross rods shall be 0.148" diameter. Cross rods shall be spaced not more than 16" o.c. with 0.188" diameter eye sections welded at 16" o.c. for pintle. 3. Deformed reinforcing bars: conform to ASTM A-615, Grade 60. Reinforcing shall be detailed, fabricated and placed per ACI 315, "Details and Detailing Reinforced Concrete Structures" and C.R.S.I. "Manual of Standard Practice." Reinforcing shall be supported and wired together to prevent displacement during grouting. 4. Wall ties with dovetail anchors: Shall be an approved type of corrosion proof metal, rigid and durable, not less than 3/16 inch diameter or 1 inch wide by 1/8 inch thick. 5. Mill Test reports in triplicate shall be furnished. C. Mortar: Conform to ASTM C270, Proportion Specification, Use Type S mortar for masonry block construction. D. Cement: Conform to ASTM C150, Type 1 Portland Cement. Type III may be used in cold weather. Use of air-entrained cement is prohibited. Use of masonry cement, conforming to ASTM C 91, may be used when approved by the Architect. E. Grout: Minimum compressive strength of 2,000 psi. F. Hydrated Lime: Conform to ASTM C207. Type S, at least 92 percent hydrated. G. Mortar Aggregate: Clean natural sand, used with or without coarse aggregate shall conform to ASTM C 144. H. Water Potable and free of substance harmful to mortar. I. Accelerators: Do not use any accelerators, anti-freeze compounds, or calcium chloride. J. Mixes REINFORCED CONCRETE MASONRY SECTION

4 1. Mortar: For concrete masonry work, a suggested mix for mortar for general use is the following proportions by volume: a. Type S: 1) One part Portland Cement 2) One half part hydrated lime 3) Four and one-half parts sand 2. Grout: For grouting of cavities and bond beams, a suggested mix is the following proportions by volume: PART 3 - EXECUTION 3.1 GENERAL a. Fine Grout: 1) One part Portland Cement 2) Three parts sand 3) Water for fluid consistency (8" slump) b. Course Grout: 1) One part Portland Cement 2) Three parts sand 3) One part pea gravel 4) Water for fluid consistency (8" slump) A. Do not build masonry on frozen surface or on surfaces having frost or standing water. B. Lay all masonry plumb, level, true to line, in full beds of mortar, with accurately spaced courses. C. All exterior concrete masonry units shall be laid with full mortar coverage on vertical and horizontal face shells. Tool joints smooth and tight with mortar of workable consistency. D. Adequately brace all masonry walls until permanent supports and structure are in place. E. Set all loose lintels, filling in around steel solidly with mortar. F. Use a masonry saw for cutting of all masonry work. G. Unless otherwise noted, load bearing masonry walls shall extend up the underside of deck above and anchored to the deck. H. Non-load bearing masonry partitions shall be kept free of structural members and laterally braced. I. Masonry shall be kept free of steel columns by use of compressible filler. J. Provide expansion joints as detailed. REINFORCED CONCRETE MASONRY SECTION

5 K. Lay 8 inches of solid masonry below any structural member. L. For starting course on footings where cells are not grouted, spread out full mortar bed including areas under cells. M. Fabricate reinforcing in accordance with ACI 315. N. Where bond beams are shown, use special units to allow for placement of continuous horizontal reinforcing. O. Provide control joints in exterior concrete block walls at locations shown on architectural drawings, in line with control joints in brick, unless noted otherwise. For all bearing walls, provide control joints at a maximum of 24'-0" center to center, unless noted otherwise. 3.2 TOLERANCES A. Erect masonry within the following tolerances from the specified dimensions: 1. Variation from plumb a. in any 10 feet of height - 1/4" b. in any 20 feet of height - 3/8" c. Maximum for entire height - 1/2" 2. Variation from true to a line a. in any 10 feet of length - 1/4" b. in any 20 feet of length - 3/8" c. Maximum for entire length - 1/2" 3. Variation from level a. in any 10 feet of length - 1/4" b. Maximum over entire length - 1/2" 3.3 TOOLING AND POINTING A. See Architectural Drawing for joint type. B. Upon completion, tuck point all exposed masonry, fill all holes and joints, remove loose mortar, and cut out defective joints and repoint to match adjacent work. 3.4 REINFORCING AND FLASHING A. Horizontal reinforcement shall be placed at a maximum of 16 inches on center. B. Horizontal reinforcement shall be lapped 16 inches at all splices. C. Provide prefabricated corners and tees at all wall intersections. D. Wall ties and dovetail anchors shall be placed 16 inches on center vertically and 16 inches on center horizontally. REINFORCED CONCRETE MASONRY SECTION

6 E. Throug-wall flashing shall start 1/2 inch from outside face of wall, carried through wall, turning up where possible to facilitate flow through weep holes mortar above and below. F. Deformed reinforcing bars shall be securely supported in placed at intervals not greater than four feet on center. G. The clear distance between vertical reinforcing and masonry shall be at least 3/4". 3.5 GROUTING A. Grout may be placed as either 'high lift' or 'low lift'. See special detail for cleanouts required for 'high lift' grouting. B. Grout shall be placed in lifts not to exceed five feet. Mechanically vibrated grout to insure complete filling of the cells. C. All grout used in walls shall be fine grout. Course grout shall only be used for lintels and bond beams. D. Stop grout 1 1/2 inches from top of block. E. Prior to grouting, inspect and clean out grout spaces. F. When using the "high lift" grouting procedure, wait at least thirty minutes but not more than one hour between pours. Reconsolidate each lift by vibrating several inches into previous lift. G. Limit grout pours to sections that can be completed in one day. H. Fill cells containing steel solidly with grout, keep cells free of mortar droppings, with a minimum size cell of 2 x 3 inches. I. Install shores or bracing before starting grouting operations. 3.6 MIXING A. Mix mortar in drum-type batch mixer for not less than three minutes after all materials and water have been added. Hand mixing shall not be used. Mortar shall be used within two hours of initial mixing. B. Field mix grout in a batch mixer for at least 5 minutes. Discard grout not placed within 1 1/2 hours after water is first added to the batch. C. Grout may be ready mixed at batch plant. 3.7 WORK OF OTHER TRADES A. Consult other trades in advance to make provisions for installation of their work, to avoid cutting and patching. B. Provide pockets in walls to receive built-in items and brick-up openings after installation. 3.8 CLEANING REINFORCED CONCRETE MASONRY SECTION

7 A. Keep all work as clean as possible. Remove excess materials, mortar dropping, etc. daily. Remove mortar droppings from adjacent work before final set. Do not let mortar drop into cells that are to filled with grout. B. Leave all masonry surfaces free from mortar, laitance and other stains. 3.9 FIELD QUALITY CONTROL A. The Owner shall engage and pay a qualified independent testing laboratory to provide services pertaining to control and testing of all masonry for this project. B. The masonry unit manufacturer shall submit data verifying compliance with these specifications per ASTM C140. This data must be less than one year old. C. Verify that mortar and grout are measured and mixed per proportion specification. D. Take samples of site mixed grout being used and test in accordance with ASTM C 1019 for each 5,000 square feet of masonry. Note that this does not apply to grout mixed at a batch plant. E. When grout is mixed at a central batch plant furnish duplicate delivery tickets with each load of grout. These tickets shall indicate grout mix proportions, date and time dispatched from mixing plant. F. Contractor shall notify testing agency when work is ready for inspection and testing (if required) and shall provide access as required. G. Testing agency shall interpret tests and state in each report whether test specimens comply with requirement and shall state any deviations therefrom. H. Contractor shall correct deficiencies in masonry work which inspections and laboratory test reports indicate is not compliance with requirements. All remedial work and all additional tests necessary to show compliance shall be done at the Contractor's expense. END OF SECTION REINFORCED CONCRETE MASONRY SECTION