Radha Krishna Temple Construction
GENERAL
SUMMARY
Related Documents SECTION:
Drawings and general provisions of the contract apply to this Section.
Review these documents for coordination with additional requirements and information that apply to work under this Section.
Section Includes:
Providing formwork for concrete and shotcrete.
Providing construction joint waterstops.
Installing cast-in anchors, inserts, sleeves and similar items furnished under other Sections.
Related Sections:
Division 01, Section 010000, General Requirements.
Division 01, Section 013500, Special Procedures.
Division 03, Section 032000, Concrete Reinforcing.
Division 03, Section 033000, Cast-in-place Concrete.
REFERENCES
General:
The following documents form part of the Specifications to the extent stated. Where differences exist between codes and standards, the one affording the greatest protection shall apply.
Unless otherwise noted, the referenced standard edition is the current one at the time of commencement of the Work.
Refer to Division 01, Section 010000, General Requirements, for the list of applicable regulatory requirements.
State of California, Department of Transportation (CALTRANS):
Standard Specifications.
ACI – American Concrete Institute:
ACI 301 Specifications for Structural Concrete.
ACI 347 Guide to Formwork for Concrete.
ACI 318 Building Code Requirements for Structural Concrete and Commentary.
California Code of Regulations, Title 8, Section 1717, Falsework and Vertical Shoring.
SUBMITTALS
Submit under provisions of Division 01, Section 010000, General Requirements.
Product data for proprietary products, including forming accessories, waterstops and joint systems.
Schedule showing Subcontractor’s proposed location of construction joints not indicated on Drawings.
Shop Drawings: For Architectural Concrete surfaces, show form construction including jointing, reveals, pattern of form ties and other items that affect appearance of exposed surface. Indicate method of sealing forms against leakage at panel joints and form ties.
Samples: Only as requested by University's Representative.
Formwork Drawings: Design and construction of all forms and form supports, shoring and bracing methods, and their adequacy shall rest with the Subcontractor. Submit drawings and samples of formwork for architectural concrete grade of tie placement concrete surfaces. Show the forms to be used indicating form construction, type and location of form ties, reveal strips, drip, groove, pattern for and method of sealing forms against grout leakage and other items that affect exposed concrete visually. Lay out form ties in regular, symmetrical patterns.
Delegated Design Submittals: Submit detailed calculations and drawings of formwork.
For installations 12 feet or higher and/or with horizontal span lengths exceeding 16 feet, design shall be approved and signed by a Civil Engineer currently registered in California.
For all other installations, design shall be approved and signed by one of the following:
A Civil Engineer currently registered in California.
A formwork manufacturer’s authorized representative.
A licensed contractor’s representative qualified in the usage and erection of formwork.
Survey anchor bolts location and elevation prior to casting concrete.
PRODUCTS
FORM MATERIALS
Form Materials: Plywood, steel fiberglass reinforced plastic, or any material that will produce concrete with the required finish and within the specified tolerances.
Use of aluminum form materials in contact with concrete is prohibited.
Smooth Form Finish: PS1 plywood intended for concrete formwork, edge sealed, no mill oil. Type B-B Plyform, MDO or HDO overlain plywood.
Where finish is exposed to view in completed construction, use only overlain plywood.
Architectural Concrete: [HDO plywood made specifically for forming Architectural Grade Concrete.]
EPS Foam for Forming: Provide load-bearing foam, except as otherwise designated or approved by the University’s Representative.
Load Bearing: ASTM C578, Type XIV (40 psi) expanded polystyrene foam (EPS) or extruded polystyrene foam (EPSX) with equal compressive strength and stiffness. Acceptable products: Insulfoam XIV by Insulfoam, or approved equal.
Void Form: ASTM C578, Type IX (25 psi) expanded polystyrene foam (EPS). Material is intended for use where foam serves only as void form for concrete placement and is not required for support of load in completed work. Acceptable products: Insulfoam IX by Insulfoam, or approved equal.
ACCESSORIES
Form Ties: Snap off metal tie of fixed length with plastic cone, designed to prevent spalling of concrete upon removal. Provide units that will leave no metal within 1-inch (25 mm) of concrete surface.
[Waterstop Type 1: Flexible PVC (polyvinyl chloride) waterstop as manufactured by Greenstreak, profile style number 771, or equal.
The PVC waterstop shall be extruded from an elastomeric plastic material of which the basic resin is prime virgin polyvinyl chloride. The PVC compound shall not contain any scrapped or reclaimed material.
Performance Requirements as follows:
Property
Test Method
Required Limits
Water absorption
ASTM D 570
5% max.
Tear Resistance
ASTM D 624
285 lb/in. min.
Ultimate Elongation
ASTM D 638
360% min.
Tensile Strength
ASTM D 638
2000 psi
Low Temperature Brittleness
ASTM D 746
No Failure @ -35° F
Stiffness in Flexure
ASTM D 747
600 psi
Specific Gravity
ASTM D 792
1.4 max.
Ozone Resistance
ASTM 1149
No Failure
Volatile Loss
ASTM D 1203
0.50% max.
Hardness, Shore A
ASTM D 2240
65 to 80
Tensile Strength after accelerated extraction
CRD-C 572
1600 psi min.
Elongation after accelerated extraction
CRD-C 572
300% min.
Effect of Alkalis after 7 days: weight change
hardness change
CRD-C 572
Between –0.10% and +0.25% +/-5 max.
Provide factory made waterstop fabrications for changes of direction, intersections, and transitions leaving only straight butt joint splices for the field.
Provide hog rings or grommets spaced at 12 inches (305 mm) on center along length of waterstop.
Provide Teflon coated thermostatically controlled waterstop splicing irons for field butt splices.]
[Waterstop Type 2: Volclay Waterstop - Rx® - 101 T by CETCO Building Materials Group, or equal.]
Reveal Strips: Profile as shown on the Drawings.
Form Release Agent: Water-based, colorless, nonstaining, chemically active agent that shall not impair bonding of paint or other coatings intended for use. Formulated for use on form facing material.
Lumber, plywood or MDO overlain plywood:
Nox-Crete Foam Coating E by Nox-crete,
Duogard II by W. R. Meadows,
or approved equal.
HDO overlain plywood, steel or fiberglass:
Nox-crete PCE by Nox-crete,
Duogard by W. R. Meadows,
or approved equal.
Expansion Joint Filler:
Fiber-Type: Preformed asphalt impregnated fiber, ASTM D1751, 1/2 inch thick, unless otherwise noted.
Foam-Type: Closed cell foam. ASTM D5249, Type 2 and ASTM D1752, Sections 5.1 to 5.4 at 10% minimum to 25% maximum expansion, 1/2 inch thick, unless otherwise noted.
Leave-in-place Stakes: Leave-in-place solid PVC or HDPE stakes, intended to serve as a permanent plug in vapor barrier, as necessary for screed stakes and to support formwork for slab on ground construction over vapor retarder. VaporStake by VaporStake, LLC, or approved equal.
EXECUTION
CONSTRUCTION OF FORMS
Design, construct and maintain formwork in accordance with ACI 347.
Provide positive means of adjustment, such as wedges and jacks, or shores and struts. Adjust formwork before and during concrete placement to achieve the specified tolerances.
Tolerances: Finished work shall conform to tolerances of ACI 117.E.
Tolerance for offsets at panel edges in as-cast condition shall conform to ACI 117, Class A for Architectural Concrete, Class B for other surfaces exposed to view, and Class C for all other surfaces.
Construct forms mortar-tight and in a manner to permit removal without damaging the concrete.
Verify that sleeves and other openings, offsets, recesses, channel chases, anchors, ties and inserts are in place before concrete is placed.
Earth Forms: Footing forms may be omitted and foundation concrete may be placed directly into neatly and accurately cut excavations, provided the excavation walls are stable, a minimum of one inch and maximum of three inches outside the concrete edges indicated on the drawings.
Where sides are unstable or excavations are not accurately cut to tolerances of ACI 301, construct formwork to the extent required, at no additional cost to Owner.
Hand trim sides and bottom of earth forms; remove loose dirt prior to placing concrete.
Provide temporary openings in formwork at the base of wall and column forms to allow inspection and cleaning before concrete placement.
Provide blockouts for mechanical and electrical work wherever necessary, even though not shown on the Drawings.
Provide 3/4-inch (19 mm) chamfers for external corners.
Provide reveal feature strips as shown.
Plywood Forms at Exposed Surfaces:
Keep number of panel joints to practical minimum.
Ensure vertical joints are plumb and horizontal joints are level.
Align form ties vertically and horizontally.
Formwork for Architectural Concrete surfaces:
Conform to requirements of Architectural Concrete section of ACI 301.
Limit deflection of form facing materials between studs, as well as deflection of studs and walers to 0.0025 times the clear span (L/400).
Arrange joints in facing material in geometric pattern as approved by the University.
Locate form ties in symmetric pattern within panels as shown or as approved by University. Use ties specified for Architectural Concrete. Provide "dummy" cones where required to match pattern shown.
Form inside corners so that no concrete is placed against panel edges.
Seal panel joints and penetrations with gaskets and/or sealant to make watertight.
Shoring: Shores and struts shall be provided with positive means of adjustment and settlement shall be taken up during construction.
Form Release Agent: Apply a coating of form release agent immediately before use, but prior to installation of reinforcing steel and embedded items.
Construction Joints:
Provide where shown or noted on the Drawings or as approved by the University.
Provide key indentations at formed joints.
Prevent formation of shoulders and ledges.
Waterstops: Install in construction joints where shown or noted on Drawings. Install in accordance with manufacturer's written instructions, including location, surface preparation, adhesive primer, and butting or lapping of ends.
Expansion Joints: Provide expansion joints and isolation joints where shown or noted on Drawings. Place joint filler in straight line with edge held back 1/8 inch (3 mm) from concrete surface and secured to formwork or previously placed construction.
Hold edge back by width of joint where joints are scheduled to receive sealant.
FIELD INSPECTION
Formwork and related components including bracing and shoring shall be inspected for conformity with the working drawings prior to the placement of concrete.
For installations 12 feet or higher and/or with horizontal span lengths exceeding 16 feet, inspection shall be performed by a Civil Engineer currently registered in California.
For all other installations, inspection shall be performed by one of the following:
A Civil Engineer currently registered in California.
A formwork manufacturer’s authorized representative.
A licensed contractor’s representative qualified in the usage and erection of formwork.
The person performing the inspection shall certify in writing that the falsework or vertical shoring system conforms to the working drawings and that the material and workmanship are satisfactory. The certification shall be available at the job site.
REMOVAL OF FORMWORK
Do not remove forms until concrete has hardened and attained sufficient strength to permit safe removal and adequate support of inherent and imposed loads. The estimate of in-place concrete strength shall be based on tests of field-cured cylinders or on other procedures to evaluate concrete strength approved by the licensed design professional and, when requested, approved by the University. It shall be the Subcontractor’s responsibility to limit construction loads to those which can be carried safely by the developed strength of the structure at the time of loading and by formwork and shoring in-place at the time of loading.
Remove forms carefully to avoid damaging corners and edges of exposed concrete. Prying against the face of concrete shall not be allowed.
After concrete is placed, forms and shores shall remain in place for not less than the following period of time, subject to requirements for additional curing:
Columns: 24 hours, unless otherwise noted.
Walls: 2 days, unless otherwise noted. 7 days for Architectural Concrete and other concrete surfaces exposed at building exterior.
Beams Sides: 2 days, unless otherwise noted.
Undersides of Beams and One-Way Slabs: Maintain formwork 7 days; shore until concrete achieves design compressive strength, 21 days minimum. Install re-shores, as necessary, where placement continues above.
Flat Slabs: Maintain form facing material 7 days; shore until concrete achieves design compressive strength, 21 days minimum.
Form facing material and horizontal supports may be removed after 3 days where formwork system allows shores to remain in place undisturbed by removal of formwork.
Upon removal of form facing material, install re-shores as soon as practical, but not longer than 4 hours after stripping.
Where concrete placing continues on upper levels, shoring may be required to be in place longer than minimum time noted for purpose of supporting weight of floor or roof pours above.
Where forms are removed in less than 7 days, curing shall be continued as follows:
Immediately following form removal thoroughly wet surface.
Continue curing in accordance with provisions of Division 03, Section 033000, Cast-in-Place Concrete.
Reuse of Forms: Forms may be reused provided they are straight, clean, free from nails, dirt, hardened concrete, rust, and other injurious matter and edges and surfaces are in good condition.
Clean and repair damage caused by placing, removal, or storage. Reuse of formwork that would reduce quality of exposed-to-view concrete will not be permitted.
Forms shall not be reused for Architectural Concrete if there is evidence of surface wear or defect that would impair the quality of the surface.
END OF SECTION 031100
CONCRETE FORMING SPECIFICATIONS