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Choosing the Choosing the RIGHTRIGHT

Formwork System Formwork SystemBCN 3423 - Timber/Formwork Design

Rinker School of Building Construction

University of Florida

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Why worry about the Why worry about the Choice of Forming Choice of Forming

System?System?

Chek Lap Kok Airport (Hong Kong)

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Concrete Frame CostsConcrete Frame Costs

Formwork: 50 - 70%

Petronas Tower

Rebar: 15 - 25%

Concrete: 15 - 25%

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Formwork CostFormwork Cost

Labor: 50 - 70%

Material: 15 - 20%Other: 10 - 15%

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What Choices Do I What Choices Do I Have?Have?

Let’s focus on:Let’s focus on:• Walls

• Slabs

• Columns

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Wall FormingWall Forming

• Walls– Loose Framing

– Prefabricated Panels

– Crane Set Gangs

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Wall Systems Wall Systems (Loose Framing)(Loose Framing)

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Wall SystemsWall Systems (Prefabricated Panels)(Prefabricated Panels)

Prefab Steel Panel Prefab Alum. Panel

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Prefabricated PanelsPrefabricated Panels• are durable for many reuses• simplify and reduce the labor required• studs and sheathing are preassembled in units

small enough to be handled• panels are set into position and tied together• wales, ties, and braces are then attached

• made of wood, metal, plywood with metal bracing, or glass fiber and plastic over wood

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Prefabricated PanelsPrefabricated Panels

Aluminum Panel

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Wall SystemsWall Systems (Ganged Panel Forms)(Ganged Panel Forms)

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Ganged Panel FormsGanged Panel Forms• ranging up to 30x50 ft• large panels can be assembled flat on the ground

where it is easier to work• stripping is easier (stripped as a unit)• extra bracing is required to withstand the

handling stresses• are frequently used as “climbing” forms in high

wall construction

• small panels can be ganged together to form larger units

13Aluminum Beam Gang Systems

15Steel Crane Set Gangs

16Shearwall Roll Back System

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Shear Wall Roll Back SystemShear Wall Roll Back System

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Slipform ConstructionSlipform Construction• vertical slipforms are moved upward by jacks• can be used for structures such as silos, and for

high rise elevator and stairway cores• working decks and finisher’s scaffolds are

attached to and carried up with the forms• has shorter construction time• appropriate for structures taller than 40 ft• not efficient where there are many projections

to the direction of slide

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Vertical SlipformsVertical Slipforms

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One-sided Wall Form One-sided Wall Form

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Slab ShoringSlab Shoring

• Loose Wood Framing• Steel or Aluminum Shoring• Flying Forms

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Hand-set Wood ShoringHand-set Wood Shoring

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Steel shoring with aluminum beamsSteel shoring with aluminum beams

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Aluminum shoring with aluminum beamsAluminum shoring with aluminum beams

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Flying Forms (truss-supported)Flying Forms (truss-supported)

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Flying Form (column-mounted)Flying Form (column-mounted)

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Flying Form (column-mounted)Flying Form (column-mounted)

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Tunnel FormsTunnel Forms

Forms wall and slab together

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Garage Beam FormsGarage Beam Forms

Panelized system for garage beams

and slabs

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Column FormingColumn Forming

• Columns– Loose Framing

– Hand-set Panels

– Crane Set Gangs

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Column FormsColumn Forms

Hand-set Steel Panel Hand-set Aluminum

Panel

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Column FormsColumn Forms

Round Fiberglass

Column Forms

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Column FormsColumn Forms

Steel Column Forms

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Column FormsColumn Forms

Aluma Beam Column Forms

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Custom FormsCustom Forms

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Custom FormsCustom Forms

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ChoicesChoices

Nothing else withstanding,

the choice is always….

GANG PANELS!

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Factors in the ChoiceFactors in the Choice

• What you own

• Availability

• Initial price

• Total cost

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Factors in the ChoiceFactors in the Choice• Experience of workers

• What will produce the desired results with the least amount of cost?

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Factors in the ChoiceFactors in the Choice• Number of uses

• Desired finish

• Site conditions

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Factors in the ChoiceFactors in the Choice• Crane

• Schedule

• Building design

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Factors in the ChoiceFactors in the Choice

• History with similar projects• Engineering expertise• Support services• Knowledge of support

personnel• Location

The Supplier:

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Buy vs. RentBuy vs. Rent• Duration of project• Future usage• Cash flow• Return on

investment

Steel radius wall forms

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ThThee

EnEndd