832571250 PWS Appendix D - Rigid Grid Access Flooring.pdf

UNCLASSIFIED

APPENDIX B:

RIGID GRID ACCESS FLOORING

HAW RAISED FLOOR AND CRAH UPGRADE

EFFECTIVE DATE: 10 SEPTEMBER 2020

UNCLASSIFIED – FOR OFFICIAL USE ONLY Page 1 of 4

PART 1 GENERAL

1.1 SCOPE

This specification details the salient features access floor systems.

Ensure onsite storage conditions meet the minimum requirements by the manufacturer to ensure warranty coverage. Provide physical installation to the final location inside the facility.

PART 2 PRODUCTS

2.1 SYSTEM DESCRIPTION

The contractor shall provide new bolted stringer-type modular access flooring system which will align with the adjacent, existing finished floor height. Underfloor plenum is approximately 24 inches high.

2.1.1 Design Requirements

The access flooring system must include the following design requirements:

a. Structural floor capacities.

b. Lateral stability of floor support system independent of panels.

c. Easily removable floor panels.

d. Self-alignment of floor panels.

e. Finished assembly that is rigid and free of vibration, noises, and rocking panels.

f. Adjustable pedestals, capable of supporting a 5000 pound axial load without permanent deformation, when tested in accordance with CISCA Access Floors for Pedestal Axial Load Test.

g. Design Load:

(1) Solid floor tiles capable of supporting a load of 2500 pounds on 1 square inch, at any point on panel, without a top-surface permanent set ≤ 0.01 inch when tested in accordance with CISCA Access Floors, Concentrated Loads with test panels supported by understructure to be used with installed system instead of steel support blocks.

(2) Perforated floor tiles capable of supporting a static load of 1250 pounds, at any point on panel, without a top-surface permanent set ≤ 0.01 inch when tested in accordance with CISCA Access Floors, Concentrated Loads with test panels supported by understructure to be used with installed system instead of steel support blocks.

h. Rolling Load: Solid panel tested on actual understructure system capable of withstanding the following rolling loads when applied at any location on the panel without failing (≤ 0.04 inch permanent set) when tested in accordance with CICSA Access Floors, Rolling Loads:

(1) 1500 pound rolling load applied through a hard rubber surfaced wheel 6 inch diameter by 2 inch wide for 10,000 passes

(2) 2000 pound rolling load applied through a hard rubber surfaced wheel 3 inch diameter by 1 13/16 inch wide caster for 10 passes.

i. Impact Load: Solid panel tested on actual understructure system capable of withstanding 150 pounds dropped from a height of 36 inches onto a 1 square inch area anywhere on the panel without failure of the system, according to CISCA Access Floors, Drop Impact Load Test.

j. Ultimate Load: Solid panel must meet manufacturer’s published Ultimate Load rating of at least 5000 pounds when applied through a load indentor on a 1 square inch area at any location on the panel without failure, tested in accordance with CISCA Access Floors, Ultimate Loading.

RIGID GRID ACCESS FLOORING

UNCLASSIFIED – FOR OFFICIAL USE ONLY Page 2 of 4

k. Safety Factor: Solid panel must provide a minimum Safety Factor of 2 times the design load rating on a 1 square inch area anywhere on the panel without failure when tested in accordance with CISCA Access Floors, Ultimate Loading.

l. Panel Drop Test: Panel must be able to be dropped face up onto a concrete slab from a height of 36 inches, after which meeting all load performance requirements.

m. Panel Cutout: A panel with an 8 inch diameter interior cutout must maintain the design load strength with a minimum safety factor of 2 anywhere on the panel when tested on the actual understructure.

n. Flammability: Meet Class A flame spread requirements for flame spread and smoke development when tested in accordance with ASTM E-84.

o. Combustibility: All access floor system components must qualify as non-combustible when tested in accordance with ASTM E-136.

p. Axial Load: Pedestal support assemblies provides a 6000 pound axial load without permanent deformation when tested in accordance with CISCA Access Floors, Pedestal Axial Load Test.

q. Overturning Moment: Pedestal support assemblies provides an average overturning moment of 1000 in-lbs when adhered to a clean, level, uncoated concrete surface and tested in accordance with CISCA Access Floors, Pedestal Overturning Moment Test

r. Stringer Concentrated Load: Strings must withstand a concentrated load of 450 pounds placed in the midspan on a 1 square inch area using a round or square indentor with a permanent set ≤0.010 inch after load is removed and tested in accordance with CISCA Access Floors, Stringer Load Testing.

2.1.2 Performance Requirements

2.1.2.1 Seismic Performance

Units must withstand the effects of a seismic event. Provide all necessary bracing and supports to meet requirements for installation for the site seismic design category in accordance with IBC.

The term “withstand” means “the unit remains in place without separation of any parts when subject to the seismic forces specified and remain fully operational after the seismic event.”

2.2 COMPONENTS

2.2.1 Floor Panels

2.2.1.1 Panel Configuration

Base access floor system on a 24 by 24 inch square module providing minimum of 24 inch clearance between structural floor and finished working floor. Fabricate so accurate job cutting and fitting may be done using standard sizes for perimeters and around columns.

Do not expose metal on finished top surface of panels. Provide cutouts and cutout closures to accommodate utility systems and equipment intercabling. Reinforce cutouts to meet design load requirements. Provide extra support pedestals at each corner of cutout for cutout panels that do not meet specified design load requirements.

Panel design must provide for convenient panel removal for underfloor servicing and for openings for new equipment. Use panels of uniform dimensions within specified tolerances. Permanently mark underside of panels to indicate manufacturer and model number.

Machine square floor panels to within the following tolerances:

a. Floor Panel Length: ± 0.010 inch.

b. Floor Panel Edge Straightness: ± 0.0025 inch.

c. Floor Panel Flatness: ± 0.035 inches on diagonal.

RIGID GRID ACCESS FLOORING

UNCLASSIFIED – FOR OFFICIAL USE ONLY Page 3 of 4

d. Floor Panel Squareness: ± 0.030 inch in panel length.

2.2.1.2 Lightweight Concrete Filled Panels (Exposed Concrete)

Provide floor panels in accordance with the following:

a. Lightweight structural concrete fully encased in top sheet steel with either structural reinforcing or a die-formed, hot dipped galvanized steel bottom pan.

b. All ferrous exposed materials must have a factory applied corrosion resistant finish. Zinc electroplating is prohibited

c. Interchangeable

2.2.1.3 Air Supply Panels

Provide the manufacturer's standard registers, grilles, perforated panels, and plenum dividers type where indicated.

Provide perforated air supply floor panels in accordance with the following:

a. Fabricated of 14-gauge perforated steel sheet welded to minimum 16-gauge side channels

b. Perforations must meet the following, unless otherwise specified in Contract documents:

(1) 25% open area

(2) Uniform pattern

c. Dampers and flow-controlled perforated floor tiles are not permitted, unless authorized in Contract documents.

d. Rated for loads up to 1250 pounds

e. Class A flame spread rating

2.2.1.4 Floor Covering

Provide floor panels with factory applied High Pressure Laminate (HPL) firmly bonded in place with waterproof adhesive in accordance with the following:

a. Bolt heads or similar attachments must not rise above the traffic surface. Submit three separate samples of each specified floor covering finish and color.

b. Provide factory applied low-sheen matte HPL surfacing in accordance with ANSI/NEMA LD 3, High- Wear type, Grade HDH, 1/16 inch (1.5 mm) thickness minimum. Finish material must consist of one piece to cover the face of the panel, with an edge detail integral to the finish material.

c. The total system electrical resistance from the wearing surface of the floor must be between 1,000,000 ohms (1.0 x 10⁶) and 2,000,000,000 ohms (2 x 10¹⁰) surface to ground resistance when tested at 500 volts, 50% relative humidity and 72°F.

d. HPL color must be a manufacturer standard color selected by DISA.

e. The conductive properties of the Nevamar Standard Grade HPL are acceptable.

f. Bond strength of floor covering must be sufficient to permit handling of the panels by use of the panel lifting device, and to withstand moving caster loads up to 2000 pounds, without separation of the covering from the panel.

g. Refurbished panels are not permitted.

2.2.2 Floor Panel Support System

Zinc electroplating is prohibited on all components of the floor panel support system.

RIGID GRID ACCESS FLOORING

UNCLASSIFIED – FOR OFFICIAL USE ONLY Page 4 of 4

2.2.2.1 Pedestals

Provide pedestals in accordance with the following:

a. Fabricated of all-welded steel.

(1) Ferrous materials must have a factory-applied corrosion-resistant finish.

b. Base plates:

(1) Minimum of 16 square inches of bearing surface

(2) 1/16 inch thickness.

c. Threaded shafts to permit height adjustment within a range of approximately 2 inches, overall floor adjustment within ± 0.10 inch of the required elevation, and to permit leveling of the finished floor surface within 0.062 inch in 10 feet in all directions.

d. Locking devices to positively lock the final pedestal vertical adjustments in place.

e. Pedestal caps must interlock with stringers to preclude tilting or rocking of the panels.

Support panels by adjustable pedestal assemblies which positively locate, engage and secure panels and which accommodate horizontal stringer members. Provide pedestals of steel or aluminum capable of carrying a 5,000 pound axial load without permanent deformation.

Ensure adhesive used to secure pedestals is compatible with epoxy subfloor coating.

2.2.2.2 Stringers

Provide 4 foot long stringers of rolled steel or extruded aluminum, to interlock with the pedestal heads to prevent lateral movement. Provide stringers that can be added or removed after floor is in place. Stringers must support each edge of the floor tile.

PART 3 EXECUTION

Not Used.

- - End of Section - -