specs

Section 03300
Page 7
mixing water as required to control temperature of mixture.
a. Conform to ACI 305.
b. Make provisions for windbreaks, shading, fog spraying, sprinkling or wet cover when necessary.
c. Use evaporation retarders, and finishing aids when necessary to achieve sound, durable surfaces.
C. Composite Concrete / Steel Construction
1. Do not place concrete until inspection and measuring requirements of the structural steel and composite
metal floor deck and field welded shear stud specifications are complete.
2. Where concrete is to be placed on unshored steel beams, take special care to prevent excessive deflection
of beams during construction.
3. For beam spans greater than forty feet, place concrete from the center of the beams, working towards both
ends simultaneously.
4. Concrete slabs placed on unshored steel beams shall be screeded to the required slab thickness above
metal deck (i.e. shall not be leveled).
D. Floor Flatness and Levelness Tolerances:
1. Unshored suspended slabs: floor slab thickness shall not vary by more than 1/4 inch from design
thickness. See Division 5 sections for steel frame tolerances. Laser leveling of floor slab surface shall not
be used.
3.04. FINISHING EXPOSED CONCRETE SURFACES
A. General
1. Comply with ACI 302.
2. Double screed slabs at required elevations.
3. Provide camber as required.
4. Apply finishing products and cure in accordance with manufacturers' recommendations.
B. Slab Surfaces
1. Float Finish
a. Locations
(1) Initial finish for all horizontal surfaces
(2) Method - after concrete has been placed, consolidated, struck off and leveled begin first float.
Check levelness and correct as required during first float. Second float shall produce a uniform
and true surface with a sandy texture.
2. Smooth Trowel Finish
a. Locations - all floor slabs except where specifically required otherwise.
b. Method - Jitterbug or tamp surfaces, screed to proper elevation, then float with metal or wood floats.
After concrete has set sufficiently to support weight, use mechanical floats to refinish leveling. After
water sheen has disappeared from surfaces, trowel with steel trowel to smooth surface free from
blemishes and trowel marks. Perform final troweling after concrete is so hard that no mortar
accumulates on trowel and a ringing sound is produced as trowels are drawn over surfaces.
3. Broom Finish
a. Locations - Exterior flatwork surfaces.
b. Method: After float finish, power-trowel and provide coarse striations with a stiff fiber brush. Orient
grain across the width of walks and as directed in other areas. After brushing, provide indentations
perpendicular to the slope of the ramp approximately 1/4th inch wide and deep and at 6 inch intervals
with a metal grooving tool. Match texture of approved mock-up.
4. Non-Slip Finish:
a. Locations: Interior steel pan type stair treads and platforms, exterior concrete stair and ramps.
b. Method: After floating, but before troweling, apply abrasive aggregate to surface in accordance with
manufacturer's recommendations, then steel trowel to a smooth, even finish. Rub finished surfaces
with abrasive stone or sandblast to remove laitance or cement coating in order to expose abrasive
aggregate.
C. Saw-Cutting Concrete Slabs-on-Grade
1. Saw joints as soon as possible after finishing, but only after concrete is hard enough. Concrete is hard
enough when saw blade does not dislodge aggregate and when edges of sawcut do not ravel.
2. Joints shall be a minimum of 1/4 inch wide and 1/4 of the slab thickness deep.
3. Formed strips may be used in lieu of saw-cutting in the same locations and to equal depth as sawn joints.
D. Formed Surfaces
1. General: Holes resulting from the removal of bolts or tie rods shall be solidly filled with cement grout.
NAPA CENTURY CENTER XD 12
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