HARVEY MUDD COLLEGE TEACHING AND LEARNING CENTER SECTION Page 1 of 6 VOIDED CONCRETE SLAB

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Bartholomew French
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1 Page 1 of 6 PART 1 - GENERAL 1.1 SUMMARY A. This Section specifies: 1. Voided concrete floor and roof slab system consisting of structural reinforced concrete containing hollow (bubbles) spherical concrete saving elements of various nominal thicknesses and widths; with lifting, supporting, and connecting devices. B. Related Sections include the following: 1. Division 03 Section Cast-in-Place Concrete for site poured concrete and reinforcing. 2. Division 05 Section Structural Steel for steel embed plates, supports, and hangers. 1.2 DEFINITIONS A. Filigree Elements: Precast elements consisting of 2-1/2 inches to 3 inches of filigree concrete, top and bottom wire mesh, and bubbles. 1.3 REFERENCES A. American Concrete Institute (ACI): 1. ACI 237R Self-Consolidating Concrete. 2. ACI Specifications for Structural Concrete. 3. ACI 302.1R Guide to Concrete Floors and Slab Construction. 4. ACI 315 Details and Detailing of Concrete Reinforcement. 5. ACI Building Code Requirements for Structural Concrete and Commentary. 6. ACI 347 Guide Formwork for Concrete. 7. ACI SP.66-ACI Detailing Manual. B. American Society for Testing and Materials (ASTM International): 1. ASTM A108 Specification for Steel Bar, Carbon and Alloy, Cold-Finished 2. ASTM A497 Specification for Steel Welded Wire Reinforcement, Deformed, for Concrete. 3. ASTM A615 - Standard Specification for Deformed and Plain Billet-Steel Bars for Concrete Reinforcement. 4. ASTM A706 Specification for Low-Alloy Steel Deformed and Plains Bars for Concrete Reinforcement. C. American Welding Society (AWS): 1. AWS B2.1 - Specification for Welding Procedure and Performance Qualification. 2. AWS D1.1 - Structural Welding Code - Steel. 3. AWS D1.4 - Structural Welding Code - Reinforcing Steel. D. Precast/Prestressed Concrete Institute (PCI): 1. PCI MNL-116S - Manual for Quality Control for Plants and Production of Precast and Prestressed Concrete Products. 2. PCI MNL PCI Design Handbook - Precast and Prestressed Concrete. E California Building Code (CBC) based on the 2006 International Building Code (IBC 2006) 1.4 PERFORMANCE REQUIREMENTS A. Design voided concrete slabs to withstand imposed loads with limited long-term deflection. 1. Design voided concrete slabs to withstand all dead loads and live loads: a. For Strength Design: Dead load as indicated on drawings, including all topping slabs, curbs, landscaping, superimposed loads, etc. Live load shall be 100 psf minimum unless indicated higher on drawings. b. For Serviceability Considerations (Long-term Deflection): All dead and live loads as indicated on the drawings. 2. Deflection Requirements a. Roof and Floor Slabs: The following load combination shall be used to compare deflection limits: Total long-term deflection (including live load) minus (-) initial dead load (from elastic analysis). 1) L/480 (or ¾ max.) for portions of the slabs that support or are attached to non-structural elements that are likely to be damaged by large deflections including partitions. 2) L/360 (or 1 max.) for portions of the slabs that do not support or are attached to nonstructural elements, or are attached to non-structural elements that are not likely to be damaged by large deflections, including canopies and exterior walkways.

2 Page 2 of 6 B. Additional Structural Design Requirements 1. Slab Design Strength: a. Bending: Flexure design shall be provide so that the compressive stress block does not encroach into the bubble zone. b. Shear: Shear strength of voided slab sections shall be 60% of a solid slab of equivalent thickness. c. Punching Shear: In addition to punching shear at solid slab sections, punching shall be evaluated at the interface of the solid and bubble zones using the reduced shear strength of the voided slab section (60%). 2. Slab Stiffness: a. Flexural stiffness shall be evaluated at 90% of a solid slab of equivalent thickness. b. The cracked moment for the slab shall be evaluated at 80% of that of a solid slab. c. Reduced effective depth shall be considered at the filigree panel joints. 3. Load History: The following load history shall be assumed for the design of the voided slabs: a. Slab shoring shall remain in place for 28 days, so initial loading will not occur until that time. b. A 30-day initial load duration assuming 100% dead load plus 20 psf construction live load. c. A 7-day load duration assuming 100% dead and live loads. d. Long term duration assuming 100% dead load and 50% sustained live loads. 15% of sustained live load may be used for corridors and walkways. 4. Seismic Drift: Voided slab design, including punching shear, shall consider load contribution from seismic inelastic drifts as indicated on Drawings, or provide minimum steel requirements in accordance with ACI. C. Fire Resistance: Provide designs acceptable to code requirements of authorities having jurisdiction to achieve hourly ratings as follows: 1. In accordance with equivalent thickness concept of CBC 2007 Section Cover thickness for reinforced concrete floor or roof slabs in accordance with CBC 2007 table (1). D. Design precast filigree elements to withstand initial and handling stresses. Elements shall withstand all dead loads and live loads: 1. Roof Assembly: Selfweight of voided concrete slab system and a minimum 20 psf construction live load. 2. Floor Assembly: Selfweight of voided concrete slab system and a minimum 20 psf construction live load. E. Camber: Provide camber for all voided slabs as indicated on drawings. F. Slab Restraint: Effects of slab restraint shall be considered in the design analysis. 1.5 SUBMITTALS A. Shop Drawings: Indicate panel layout, panel thickness, layout of lattice girder, layout of top and bottom mesh, side lap bars, bubble layout, layout of control strips, unit identification marks, connection details, edge conditions, bearing requirements, support conditions, dimensions, openings, openings intended to be field cut, and relationship to adjacent materials. B. Layout drawing of field placed negative and punching shear reinforcement. C. Design Data: Indicate calculations for loadings including uniform loads, point loads, and special loadings resulting from openings. Submit complete analysis and design calculations signed and sealed by Structural Engineer licensed in the State of California, including. 1. Strength design. 2. Serviceability considering long-term deflections. 3. Vibration analysis of slabs indicating acceptable vibration performance under normal footfall suitable for higher education classroom use. D. Shop Drawings and Design Data shall be submitted and reviewed by the Engineer and Architect. 1. Upon approval by Engineer and Architect shop drawings shall be submitted for review and approval by the local building jurisdiction. E. Shoring supplier shall coordinate shoring design with voided slab engineer. Shoring and reshoring shop drawings shall be stamped by a professional engineer licensed in the state of California. Voided slab engineer shall review shoring and reshoring calculations and shop drawings.

3 Page 3 of 6 F. Voided slab site poured concrete mix design shall be marked approved by voided slab engineer. G. Voided slab site poured concrete test cylinder results shall be marked approved by voided slab engineer. H. LEED Submittals: 1. Product Data for Credit MR 4: For products having recycled content, documentation indicating percentages by weight of postconsumer and preconsumer recycled content. Include statement indicating cost for each product having recycled content. 2. Product Certificates for Credit MR 5: For products and materials required to comply with requirements for regional materials, certificates indicating location of material manufacturer and point of extraction, harvest, or recovery for each raw material. Include statement indicating distance to Project, cost for each regional material, and fraction by weight that is considered regional. 3. Design Mixtures for Credit ID 1.1: For each concrete mixture containing fly ash as a replacement for portland cement or other portland cement replacements, and for equivalent concrete mixtures that do not contain portland cement replacements. 1.6 QUALITY ASSURANCE A. Design voided concrete slabs and precast filigree panels in accordance with requirements of: 1. ACI ACI 301. B. Sustainable Design Requirements: 1. Recycled Content Materials: Furnish materials with recycled content as indicated in cast in place concrete section. 2. Regional Materials: Furnish materials extracted, processed, and manufactured within 500 miles of Project site, including polyethylene bubbles and precast filigree panels. C. Sample Panels: Before fabricating units, produce a minimum of 2 sample panels approximately 16 sq. ft. in area for review by Architect. Incorporate full-scale details of architectural finishes, textures, panel joints, and transitions in sample panels. 1. Locate panels where indicated or, if not indicated, as directed by Architect. 2. Damage part of an exposed-face surface for each finish, color, and texture, and demonstrate adequacy of repair techniques proposed for repair of surface blemishes. 3. After acceptance of repair technique, maintain one sample panel at manufacturer's plant and one at Project site in an undisturbed condition as a standard for judging the completed Work. 4. Demolish and remove sample panels when directed. 1.7 QUALIFICATIONS A. Fabricator: Precast concrete fabricator shall be certified by the Precast/Prestressed Concrete Institute (PCI) Plant Certification Program. B. Welder: Qualified within previous 12 months in accordance with AWS B2.1. C. Design voided concrete slab and precast filigree panels under direct supervision of Structural Engineer experienced in design of this Work and licensed in State of California. 1.8 PRE-INSTALLATION MEETINGS A. Slab pre-construction meeting: At least 20 days prior to placing first voided concrete slab, Contractor shall hold a meeting to review detailed requirements for preparing final concrete design mixes and to establish procedures for placing, finishing, curing, and protecting concrete to meet required quality under anticipated conditions. B. Contractor shall request responsible representative of each party concerned with concrete work to attend meeting, including but not limited to following: 1. Contractors Superintendent. 2. Testing Laboratory responsible for field quality control. 3. Concrete Subcontractor s Project Manager. 4. Ready-mix Concrete Supplier. 5. Concrete Pumping Equipment Supplier. 6. Resident Project Representative. 7. Voided Concrete Slab Engineer. 8. Structural Engineer of Record. 9. Architect. 10. Owner's Project Representative.

4 Page 4 of 6 C. Discuss anchor and weld plate locations, sleeve locations, and cautions regarding cutting or core drilling. D. Minutes of the meeting shall be recorded, typed, reproduced and distributed by Contractor to all parties concerned within five working days of meeting. E. Minutes shall include a statement by admixture manufacturer (s) indicating that proposed mix design and placing can produce concrete quality required by this Section. F. During construction, additional meetings may be held to review and modify procedures and materials established to assure attainment of high quality level. 1.9 DELIVERY, STORAGE, AND HANDLING A. Division 01 Section Product Requirements for product storage and handling requirements. B. Lifting or Handling Devices: Capable of supporting member in positions anticipated during manufacture, storage, transportation, and erection. C. Precast filigree panels shall achieve adequate strength prior to handling to prevent distortion or warping. D. Number each member to show location according to layout drawings. E. Store all units off ground. F. Separate stacked members by battens across full width of each bearing point. G. Stack so that lifting devices are accessible and undamaged. H. Store so that bubbles are not damaged. PART 2 - PRODUCTS 2.1 VOIDED SLAB SYSTEM SUPPLIERS A. Voided slab system shall be manufactured by BubbleDeck. 2.2 MATERIALS A. Filigree Concrete Materials: Self-consolidating concrete; Compressive strength (28 days) f c = 5000 psi. B. Molds: Rigid, dimensionally stable, non-absorptive material, warp and buckle free, that will provide continuous and true precast concrete surfaces within fabrication tolerances indicated; nonreactive with concrete and suitable for producing required finishes. C. Voided Slab Site Poured Concrete Materials: As specified in Division 03 Section Cast-in-Place Concrete ; the max aggregate size is 3/4 inch diameter for all slabs greater than or equal to 11 inch total slab thickness. The max aggregate size is 3/8 inch diameter for all slabs less than 11 inch total slab thickness. D. Reinforcing Steel: ASTM A615, Grade 60, deformed steel bars, unless otherwise noted on drawings. E. Deformed Welded Wire Reinforcement: ASTM A497, and as follows: 1. WWR Yield Strength: Provide minimum yield strength of 80,000 psi. 2. Wire Spacing and Size: Provide wire spacing and size, as calculated to maintain the specified area of steel as required by performance. F. Bubbles: High density polyethylene, with color as chosen by the manufacturer, with the following properties: 1. Must not react chemically with concrete and all reinforcing steel and welded wire reinforcement. 2. Must be non-porous. 3. Shall be of sufficient strength to carry loads induced by construction activities. 4. Safety characteristics a. Decomposition temperatures > 572 deg F b. Flashpoint > 671 deg F c. Spontaneous ignition temperature > 671 deg F G. Lattice Girders: Bars with the yield strength of 72.5 ksi and tensile strength of 80 ksi consisting of a top chord, a bottom chord, and a diagonal. H. Shear Rail Reinforcement: Plain, ASTM A108, yield strength 50 ksi, tensile strength 60 ksi. 2.3 FABRICATION A. Filigree Precast Panels: Plant cast. B. Fabricate openings required by other sections, at locations indicated.

5 Page 5 of 6 C. Panel manufacturer shall provide for openings 8 inches round, square or larger as indicated on structural drawings. D. All other openings shall be located and field drilled or cut by contractor requiring such work after precast filigree panels have been erected. E. Openings shall be approved by Engineer/Architect and manufacturer before drilling or cutting. F. Finishes: Bottom surface shall be flat and uniform without major chips, spalls, and imperfections. G. Patching: Will be acceptable providing the structural adequacy of the system, as confirmed by the voided slab engineer, is not impaired. H. Plant Finish: Finish members to PCI MNL-116S Finish A Grade. 2.4 FABRICATION TOLERANCES A. Conform to PCI MNL-116S. B. Length of precast filigree elements shall not vary from design dimensions by more than plus or minus 3/16 inch. C. Deviations from straight lines shall not exceed 1/8 inch in 30 feet. D. Precast filigree elements shall not vary by more than plus or minus 1/8 inch from true overall cross sectional shape as measured by difference in diagonal dimensions. 2.5 FINISHES A. Underside of slabs are exposed finished surface. Underside panel faces shall be free of joint marks, grain, and other obvious defects. Corners, including false joints shall be uniform, straight, and sharp. Finish exposed-face surfaces to match approved sample panels and as follows: 1. As-Cast Surface Finish: Provide surfaces free of pockets, sand streaks, and honeycombs. PART 3 - EXECUTION 3.1 PREPARATION A. Prepare support devices for erection procedure and temporary bracing. 3.2 ERECTION A. Install voided slab system in accordance with supplier s requirements. B. Contractor shall be responsible for providing suitable access to the building, proper drainage and firm, level bearing for the hauling and erection equipment to operate under their own power. C. Contractor shall be responsible for providing true, level bearing surfaces on all field placed bearing walls and other field placed supporting members. D. Contractor shall be responsible for placement and accurate alignment of anchor bolts, plates or dowels in columns and walls. E. Erect members without damage to structural capacity, shape, finish, or edges. Replace or repair damaged members. F. Bubbles shall not be significantly damaged during construction activities. Replace or repair all significantly damaged bubbles. G. Align and maintain uniform horizontal intermediate and end joints, as erection progresses. H. Maintain temporary bracing in place until final connections are made. Protect members from staining. I. Adjust differential elevation between precast filigree panels to tolerance before pouring of site concrete. J. After pouring site concrete maintain temporary shoring in place for 28 days. 1. Do not place construction loads on slab for 28 days after pouring days after pouring slab a maximum construction live load of 20 psf may be placed on the slab days after pouring slab a short term construction live load of 50 psf may be placed on the slab lasting no more than 7 days. K. Seal precast joints to prevent concrete leakage when joints between precast filigree panels have not been closely butted.

6 Page 6 of FIELD QUALITY CONTROL A. Voided slab representative and engineer shall visit the job site prior to first slab pour and at appropriate intervals thereafter (minimum of 2 visits) to ensure conformance with design. END OF SECTION

GUIDE SPECIFICATIONS For STRUCTURAL PRECAST HOLLOW CORE SLABS SECTION 03410

GUIDE SPECIFICATIONS For STRUCTURAL PRECAST HOLLOW CORE SLABS SECTION 03410 Note to user: These guide specifications are provided by Mid- States Concrete Products as a service to you; they are NOT specific