G-2 Select Concrete Forming Systems Flashcards
What is a footing?
A concrete member is used under a foundation wall or column to spread the supported weight of the building over a larger area.
What is a Foundation wall?
A concrete member that is supported by the footings and supports the above-grade portion of the building.
Fly form?
A fly form is a form that is moved with a crane.
Form Sheathing?
Form sheathing directly supports the fresh concrete and must be able to resist the force without significant deflection.
Stud?
Upright members that support the form sheathing. The spacing of the stud is governed by the allowable deflection of the form sheathing and the rate of pour.
Waler?
Horiziontal members that support the form sheathing or studs. If the form system uses single-waler brackets then the walers support the form sheathing.
Tie?
A is the load from the waler, that is transferred to the ties by the waler.
Wedge?
A wedge is used to secure snap ties.
Strongback?
Used to support and line up horizontal walers.
Brace?
Used to hold the top of the forms in place and in most cases to keep wall forms plumb.
Stake?
Used to hold the bottom of the forms in place and to set elevations of forms. Stakes are also used to anchor the bottom of braces.
Cleat?
Normally used to hold the top of the footing forms or wall forms the correct distance apart and function as a low strength tie.
Spacer?
Used to hold forms the correct distance apart. Can be used at the bottom of walls or at the top.
Kicker?
Vertical 2 by 4 to allow one set of walers to reinforce the other set of walers.
Key and keyway
Used to keep the foundation walls laterally anchored to the footings.
Dowel
Short piece of reinforcing steel bar
Mushroom Cap
Used over rebar ends to guard workers against impalement.
Corbel
A corbel is a widening in a wall, often at the top. Structural or decorative purposes.
Ledge
A concrete wall with its thickness reduced at the the top to accommodate the floor joists, brickwork or slabs.
What is architectural considerations?
Concrete that is left exposed to view.
How do most injuries occur in concrete work?
Stripping forms
What is false work?
Temporary support for formwork
What is the purpose of form sheathing?
Supporting and shaping fresh concrete.
What kind of wood is strongest for formwork?
Douglas fir
Standard form ties are made for use with what thickness of sheathing?
19 mm
How is loose-forming done?
In loose forming, concrete ties are held in place by the walers of some other mechanism designed to support the fresh concrete as well as the forms.
The formwork of pre-cast concrete is usually steel, true or false?
True
What is the purpose of a tie?
All ties consist of an internal tension unit to hold the form together and an external holding device to transfer the load from the formwork to the tie.
What two kinds of ties are stamped from sheet metal?
Strip tie and quick strip
What is a coil tie?
It has a coil of wire that forms the thread at both ends of the tie.
Describe a taper tie.
Taper ties are heavy steel rods that are tapered at both ends of the tie.
Described overlaid plywood
Form ply that has one face covered with resin-impregnated paper.
What is commonly done to concrete forms prior to each use?
Lubricated with a product that provides for form release.
What is an insert?
An insert is used to attach other building materials to the concrete
What is the purpose of a reglet?
Counter flashing fits into the reglet and overlaps roofing material to form a water-tight seal.
What is isolation joint?
Concrete cast on the ground will settle even if the sub-grade is well compacted. To allow even settling, isolation joints are placed around columns and at the perimeter of slabs. To prevent cracking.
What is a Give-And-Take-Strip?
Give-And-Take strips are used to isolate one concrete member from another and are designed to allow for vertical and horizontal movement.
Expansion joint?
Expansion joints are similar to isolation joints, they provide protection against the expansion of concrete due to high temps.
Control joints?
Control joints expand and contract with changes in temperature, to control haphazard cracking, control joints are used in larger sections of concrete.
Tooled joints?
Tooled joints are simple to control joints used for concrete sidewalks.
Plastic Control Joint Strips?
A two-part, T shaped plastic strip
Cutting Control Joints?
Control joints can be cut using a saw equipped with a diamond-impregnated blade.
Construction joint?
A construction joint is a surface where two successive placements of concrete meet.
Cold joint?
A cold joint is an unplanned joint or discontinuity in concrete that results from a delay in the placement of concrete.
What is the difference between an isolation joint and control joint?
An isolation joint is a joint between members that prevents cracking.
What is the minimum depth of a control joint for a slab on grade?
1/4 slab thickness.
What material is used for a give-and-take strip?
Impregnated Fibre Board
Describe three ways of making a control joint in a slab-on-grade
Tooled, zip strip & slab on grade.
What is the purpose of control joint?
To control random cracking.