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033053Proj. No. 10105 Residence Conversions October 7, 2011 58 Kensington, 57 Dryads Green, 72 Dryads Green Smith College, Northampton, MA MISCELLANEOUS CAST-IN-PLACE CONCRETE Page 1 of 5 033053 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.This Section specifies cast-in-place concrete, including reinforcement, concrete materials, mixture design, placement procedures, and finishes, for noncritical applications of concrete and for projects using small quantities of concrete. 1.3 SUBMITTALS A.General: In addition to the following, comply with submittal requirements in ACI 301. B.Design Mixtures: For each concrete mixture. 1.4 QUALITY ASSURANCE A.Manufacturer Qualifications: A firm experienced in manufacturing ready- mixed concrete products and that complies with ASTM C 94/C 94M requirements for production facilities and equipment. B.Source Limitations: Obtain each type of cement of the same brand from the same manufacturer's plant, obtain aggregate from one source, and obtain admixtures through one source from a single manufacturer. Proj. No. 10105 Residence Conversions October 7, 2011 58 Kensington, 57 Dryads Green, 72 Dryads Green Smith College, Northampton, MA MISCELLANEOUS CAST-IN-PLACE CONCRETE Page 2 of 5 033053 C.Comply with ACI 301, "Specification for Structural Concrete," including the following sections, unless modified by requirements in the Contract Documents: 1."General Requirements." 2."Formwork and Formwork Accessories." 3."Reinforcement and Reinforcement Supports." 4."Concrete Mixtures." 5."Handling, Placing, and Constructing." 6."Lightweight Concrete." D.Comply with ACI 117, "Specifications for Tolerances for Concrete Construction and Materials." PART 2 -PRODUCTS 2.1 FORMWORK A.Furnish formwork and formwork accessories according to ACI 301. 2.2 STEEL REINFORCEMENT A.Plain-Steel Welded Wire Reinforcement: ASTM A 185, fabricated from as- drawn steel wire into flat sheets. 2.3 CONCRETE MATERIALS A.Cementitious Material: Use the following cementitious materials, of the same type, brand, and source throughout Project: 1.Portland Cement: ASTM C 150, Type I/II. B.Normal-Weight Aggregate: ASTM C 33, graded, 1-1/2-inch (38-mm)nominal maximum aggregate size. C.Water: ASTM C 94/C 94M;potable. Proj. No. 10105 Residence Conversions October 7, 2011 58 Kensington, 57 Dryads Green, 72 Dryads Green Smith College, Northampton, MA MISCELLANEOUS CAST-IN-PLACE CONCRETE Page 3 of 5 033053 2.4 ADMIXTURES A.Air-Entraining Admixture: ASTM C 260. 2.5 CONCRETE MIXTURES A.Comply with ACI 301 requirements for concrete mixtures. B.Normal-Weight Concrete: Prepare design mixes, proportioned according to ACI 301, as follows: 1.Minimum Compressive Strength: 3000 psi (20.7 MPa)at 28 days. 2.Maximum Water-Cementitious Materials Ratio: 0.45. 3.Slump Limit: 4 inches (100 mm), plus or minus 1 inch (25 mm). 4.Air Content: Maintain within range permitted by ACI 301. Do not allow air content of floor slabs to receive troweled finishes to exceed 3 percent. 2.6 CONCRETE MIXING A.Ready-Mixed Concrete: Measure, batch, mix, and deliver concrete according to ASTM C 94/C 94M, and furnish batch ticket information. 1.When air temperature is above 90 deg F (32 deg C), reduce mixing and delivery time to 60 minutes. B.Project-Site Mixing: Measure, batch, and mix concrete materials and concrete according to ASTM C 94/C 94M. Mix concrete materials in appropriate drum- type batch machine mixer. 1.For mixer capacity of 1 cu. yd.(0.76 cu. m)or smaller, continue mixing at least 1-1/2 minutes, but not more than 5 minutes after ingredients are in mixer, before any part of batch is released. 2.For mixer capacity larger than 1 cu. yd.(0.76 cu. m), increase mixing time by 15 seconds for each additional 1 cu. yd.(0.76 cu. m). Proj. No. 10105 Residence Conversions October 7, 2011 58 Kensington, 57 Dryads Green, 72 Dryads Green Smith College, Northampton, MA MISCELLANEOUS CAST-IN-PLACE CONCRETE Page 4 of 5 033053 PART 3 -EXECUTION 3.1 FORMWORK A.Design, construct, erect, brace, and maintain formwork according to ACI 301. 3.2 STEEL REINFORCEMENT A.Comply with CRSI's "Manual of Standard Practice" for fabricating, placing, and supporting reinforcement. 3.3 CONCRETE PLACEMENT A.Comply with ACI 301 for measuring, batching, mixing, transporting, and placing concrete. B.Do not add water to concrete during delivery, at Project site, or during placement. 3.4 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 (13 mm). B.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. 3.5 FINISHING UNFORMED SURFACES A.General: Comply with ACI 302.1R for screeding, restraightening, and finishing operations for concrete surfaces. Do not wet concrete surfaces. Proj. No. 10105 Residence Conversions October 7, 2011 58 Kensington, 57 Dryads Green, 72 Dryads Green Smith College, Northampton, MA MISCELLANEOUS CAST-IN-PLACE CONCRETE Page 5 of 5 033053 B.Screed surfaces with a straightedge and strike off. Begin initial floating using bull floats or darbies to form a uniform and open-textured surface plane before excess moisture or bleedwater appears on surface. 1.Do not further disturb surfaces before starting finishing operations. C.Trowel and Fine-Broom Finish: Apply a partial trowel finish, stopping after second troweling, to surfaces indicated and to surfaces where ceramic or quarry tile is to be installed by either thickset or thin-set methods. Immediately after second troweling, and when concrete is still plastic, slightly scarify surface with a fine broom. 3.6 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. C.Curing Methods: Cure formed and unformed concrete for at least seven days by one or a combination of the following methods: 1.Moisture-Retaining-Cover Curing: Cover concrete surfaces with moisture-retaining cover for curing concrete, placed in widest practicable width, with sides and ends lapped at least 12 inches (300 mm), and sealed by waterproof tape or adhesive. Cure for not less than seven days. Immediately repair any holes or tears during curing period using cover material and waterproof tape. END OF SECTION 033053