4CASTING A CONCRETE WALL ReinforcingReinforcing for a concrete shear wall (designed to resist lateral forces such as wind or earthquake), consisting of two layers of vertical and horizontal bars.The wall is reinforced more heavily at either end, where it must resist greater stresses.
5CASTING A CONCRETE WALL ReinforcingHeavy reinforcing at the base of concrete shear walls for a large, multistory building
6CASTING A CONCRETE WALL Wall FormsSlender rods, called form ties, hold the forms in position and resist the outward pressure of the concrete when it is placed.The plastic cones prevent the formwork for sliding along the ties, and form a neat, conical hole in the finished surface of the concrete.
7CASTING A CONCRETE WALL Wall FormsForm ties can be made from steel rods (top), straps (bottom), wire, fiberglass, or other plastics.
8CASTING A CONCRETE WALL Wall FormsAfter the wall is cast and the forms removed, the protruding ends of the metal ties are broken off and the plastic cones removed.
9CASTING A CONCRETE WALL Wall FormsThe remaining holes in the concrete may be left open, filled with mortar (right), or plugged with some other material.If the broken end of a metal form tie rod is not covered, rust staining may result as the end of the tie gradually corrodes.Fiberglass form tie rods may be used without plastic cones. The protruding ends of the rods are simply ground off flush with the face of the concrete, becoming virtually unnoticeable to the untrained eye.
10CASTING A CONCRETE WALL Wall FormsRight: On the outside, the form ties engage with slotted metal wedges. The wedges restrain the horizontal walers.The walers (and sometimes vertical studs) brace the formwork panels.
11CASTING A CONCRETE WALL Wall FormsWall forms must be constructed sufficiently stiff to resist the fluid pressures of the freshly poured concrete.Right: A proprietary, modular wall form system, that can be easily raised and reused as wall construction proceeds upwards.Note the temporary scaffolding integrated into the form system, providing workers with access to the top of the wall.
15Finishing the Concrete CASTING A CONCRETE WALLFinishing the ConcreteA residential concrete foundation wall with the formwork stripped.Without special efforts, the form panels and ties leave strong patterns on the wall surface.
16Finishing the Concrete CASTING A CONCRETE WALLFinishing the ConcreteA concrete foundation wall with blockouts to create openings in the wall for passage of building services.
17Finishing the Concrete CASTING A CONCRETE WALLFinishing the ConcreteRough boards were used to line the inside of the wall forms, creating a board form finish on the cast wall.
22CASTING A CONCRETE WALL Tilt-Up ConstructionConcrete wall panels are poured lying flat, much like a slab on grade.Once the panels have gained sufficient strength, they are lifted into final position.Tilt-up construction significantly reduces formwork costs, which can account for 50 per cent or more of the cost of conventional concrete construction.