Table 4 - Minimum Concrete Cover Over Reinforcement
Cover over post-
Zone
Cover over reinforcing steel
tensioning ducts
less than those listed above
3.2.6
Setting Miscellaneous Material and Prestress Anchorages
Place and secure anchors, bolts, pipe sleeves, conduits, and other such
items in position before concrete placement. Plumb anchor bolts and check
location and elevation. Temporarily fill voids in sleeves with readily
removable material to prevent the entry of concrete. Electrically isolate
exposed steel work and its anchor systems from the primary steel
reinforcement with at least 2 inches 50 mm of concrete. Coat exposed steel
work to reduce corrosion. Take particular care to ensure against corrosion
on edges and horizontal surfaces. Use epoxy coatings for protection of
carbon steel plates and fittings.
3.2.7
Construction Joints
Locate joints to least impair strength.
Continue reinforcement across
joints unless otherwise indicated.
3.2.8
Expansion Joints and Contraction Joints
Provide expansion joint at edges of interior floor slabs on grade abutting
vertical surfaces, and as indicated. Make expansion joints 13 mm 1/2 inch
wide unless indicated otherwise. Fill expansion joints not exposed to
weather with preformed joint filler material. Completely fill joints
exposed to weather with joint filler material and joint sealant. Do not
extend reinforcement or other embedded metal items bonded to the concrete
through any expansion joint unless an expansion sleeve is used. Place
contraction joints, either formed or saw cut or cut with a jointing tool,
to the indicated depth after the surface has been finished. Sawed joints
shall be completed within 4 to 12 hours after concrete placement. Protect
joints from intrusion of foreign matter.
3.2.9
Waterstop Splices
Fusion weld in the field.
3.2.10
Pits and Trenches
Place bottoms and walls monolithically or provide waterstops and keys.
3.3
BATCHING, MEASURING, MIXING, AND TRANSPORTING CONCRETE
ASTM C 94, ACI 301, and ACI 304R, except as modified herein. Batching
equipment shall be such that the concrete ingredients are consistently
measured within the following tolerances: 1 per cent for cement and water,
2 percent for aggregate, and 3 percent for admixtures. Furnish mandatory
batch tickets imprinted with mix identification, batch size, batch design
and measured weights, moisture in the aggregates, and time batched for each
load of ready mix concrete. When a pozzolan is batched cumulatively with
the cement, it shall be batched after the cement has entered the weight
hopper.
SECTION 03311
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