Column-Mounted Shoring System Cycle

Column-mounted shoring systems are either assembled at the job site or preassembled in a local or regional yard facility and deliv­ered to the job site. Deck panels are flown from floor to floor by a crane in a manner similar to what is done in the flying truss system. Typically, the column-mounted shoring system cycle starts from the ground floor, whether or not slabs on grade exist.

Column-Mounted Shoring System Cycle

Figure 4.8 Components of bracket jack system. (Courtesy of Form­work Exchange Ltd.)

 

Подпись: Copyright © Marcel Dekker, Inc. All rights reserved.

The column-mounted shoring system cycle is described below. However, some minor technical details are different from one man­ufacturer to another.

1. Assembling the deck panel. The deck panel can be as­sembled on the ground on the job site or preassembled in the factory. Assembling the deck panel at the job site starts by bolting the trusses to the flange of the I beam. The first truss is bolted first at one end of the I beam, then the center truss, and finally the truss at the other end of the I beam. Other trusses are then placed and bolted at regular intervals. Wood joists are then placed and attached to the trusses.

Assembling the deck panel at the factory is achieved by attaching the trusses to only one I beam by one bolt so that the perpendicular trusses can be folded for ship­ment. At the job site, the trusses are unfolded and placed perpendicular to the I beam, and the other I beam is placed and attached to trusses. The remaining bolts are then fastened and tightened.

2. Подпись: Copyright © Marcel Dekker, Inc. All rights reserved.Positioning of the deck panel. The positioning starts by marking the elevation of the deck panel on the face of the column or the wall. The deck panel is then lifted by crane and positioned on the bracket jack system. The deck panel is lowered and adjusted to the previously marked elevation and then rested on the bracket jack sys­tem. Crane hooks and safety lines are then removed. After the deck is rested on the jack bracket system, instal­lation of the fillers begins. Fillers are needed to fill the gaps over the concrete columns. Also, in cases in which the concrete column sizes are reduced at higher eleva­tion, larger fillers are needed to compensate for this change in column sizes. In case the concrete columns are not aligned, a base plate is inserted between the jack bracket system and the concrete column or wall.

3. Stripping of the deck panel. After the concrete has been placed and has gained enough strength to support its own
weight and any additional loads, the deck panels are then stripped from the slab. The stripping process starts by lowering the jacks approximately 6 in. (152.4 mm) using the adjustable screws. The entire deck panel is then rolled out with use of a winch until the location of the first pair of crane hooks is outside the building line (exposed). Crane attachments and cables are then hooked and the deck panel continues to be pulled out until the second pair of crane hooks is exposed. Crane attachments and cables are hooked to the second pair of hooks and the deck panel is then carried by crane to the next floor.

In horizontal structures, deck panels can be rolled from one position to another on the rollers at the top of the jack bracket system.