#PLACING FOOTING PER FROST DEPTH CODE#

Side form spacers include double-headed nails, precast concrete blocks (dobies), and proprietary all-plastic shapes.

Spacers for vertical concrete (wall construction) have traditionally been optional.

The ill-advised practice in slab construction of placing reinforcement on the subgrade and pulling it up during concrete placement is called “hooking.”

Placing reinforcement onto layers of fresh concrete or adjusting the position of bars or welded wire reinforcement during concrete placement should not be permitted.

For example, for a one-way solid slab with #5 temperature-shrinkage bars, high chairs are used at 4 feet on center for #4 bars, high chairs would be placed 3 feet on center.

Spacing of bar supports depends upon the size of the reinforcing bar being supported.

Bar supports are not intended as support for construction equipment such as concrete pumps, buggies, or laser screeds.

This type of tie is used to secure heavy mats.Įxtra Information on Footing Rebar Placement

Detail E: 'Figure Eight Tie' can be used on walls in lieu of the saddle or wrap and snap ties.Detail D: 'Wrap and Saddle Tie' ) is similar to the saddle tie except that the wire is wrapped 1-1/2 times around the first bar, then completed like Detail C.They are commonly used for securing ties to column corner bars and stirrups to beam corner bars. Detail C: 'Saddle Tie' is more complicated than snap ties or wrap and snap ties.Detail B: 'Wrap and Snap Tie' is normally used when tying vertical wall reinforcement to hold the bars securely into place.Detail A: 'Snap Tie' is the simplest and is usually used for rebar in a flat horizontal position.There are different ways in which the tie wire is tied to the rebar depending upon the situation n place were they are tied.

Be sure to keep the ends of the tie wires away from the surface of the concrete where they could rust. When tying bars, there is no need to tie every intersection - every fourth or fifth is normally sufficient. Care must be taken to keep the ends of tie wire are away from the surface of the concrete where they could rust. Tying of all intersection is not needed, every fourth or fifth is normally sufficient. To tie the rebars, tie wire is used which is typically 16½ - or 16-gauge black, soft, annealed wire, although heavier reinforcement may require 15- or 14-gauge wire to hold the proper position of the rebar. Though the tie steel does not contribute to the strength of the reinforcement, it is used to secure and prevent the rebars from displacement during construction activities and concrete placement. The distribution ratio of length to short side is calculated based on the aspect ratio of footing as -īar supports are used to hold the reinforcing bars in place to attain the proper depth of cover.įor proper placing, rebar supports are used which comes in many sizes and of different materials such as steel wire, precast concrete, or plastic.Ĭhairs and supports are available in various heights to support specific reinforcing bar sizes and positions.

#PLACING FOOTING PER FROST DEPTH CODE#

In a rectangular footing, rebars in the long direction are placed uniformly but not the short direction.ACI code (15.4.4.2) requires a certain portion of reinforcements in a short direction to be placed within a band equal to the width of footing in the short direction. In a square footing, rebars are placed uniformly in both directions. ACI code requires that the rebars be placed not more than 18 inch apart. It is a general rule that reinforcements should be placed at the tension side at the bottom of the footing. slabs, walls, and joists - #14 and #18 bars - ½ inch.For concrete not exposed to weather or in contact with the ground:.For concrete exposed to weather or earth (such as basement walls).For concrete cast against and permanently exposed to earth (such as footings) - 3 inches.The minimum cover for cast-in-place concrete is specified by the ACI 318 Building Code.

Placing footing per frost depth