Flying to a New Position

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Flying to a New Position

Flying formwork has proved to be an efficient system in achieving a shorter construction cycle of initial fabrication, erection, strip­ping, and re-erection. Other visible benefits of flying formwork are as follows: [18] [19]

construction activities to be performed. In the traditional formwork system, several rows of shores are needed to provide support to the slab. These shores completely block any construction activity underneath the newly placed slabs for several days.

3. Costs of flying formwork are lower than for conventional horizontal formwork systems when 10 or more reuses are available. The high initial assembly cost is offset by a high number of reuses.

4. Lightweight aluminum trusses and joists allow average capacity construction cranes to handle the flying tables. Also, the lightweight aluminum joists can be placed on the aluminum trusses by one construction worker.

5. A shorter floor cycle can be achieved with use of the fly­ing formwork system. A five-day construction cycle can be achieved for a medium-sized building of 100,000 ft2 (9290 m2). Reducing the floor cycle can shorten overall construction time, leading to substantial savings in over­head and financial costs.

6. A large-size flying table results in a smaller number of deck joints which produces high-quality smooth con­crete.

7. Erecting and stripping the flying form as one large unit reduces the frequency of lifting work for the crane; this allows for crane time involvement with other construction work.

8. Подпись: Copyright © Marcel Dekker, Inc. All rights reserved.Fiberglass or steel pans used to form joist or waffle slabs can be placed on the flying tables and become an integral part of the flying table. These can be erected and stripped as one unit.

Подпись: Copyright © Marcel Dekker, Inc. All rights reserved.The table is carried by the crane, which is attached at four prede­termined pick points. To prevent any swinging from the flying ta­ble, a safety line is normally attached between the lower chord of the aluminum truss and the concrete column. The table is then flown to its new position and the cycle is repeated (steps 6 and 7, Figure 4.5). It should be noted that occasionally the trusses only are carried out from floor to floor and the table is assembled in every floor or several floors. This is because of site limitation or because bay sizes and location are different from floor to floor. Figure 4.6 shows trusses carried out by crane without the interme­diate nailers or sheets.

The total cycle time for the sequences described is approxi­mately between 20 and 30 minutes, depending on the job condi­tions.