Modular and Design Factors Affecting Selection of Column-Mounted Shoring Systems
An important criterion when using a modularized formwork system is the maximization of the number of reuses. As a result, modification to the deck panels should be kept to a minimum. Modifications to deck panels are caused by changes in building design from floor to floor. The following are some modular limitations that should be considered to achieve maximum profitability of the column-mounted shoring system.
1. Optimum size of a column-mounted shoring systems deck is 16 to 20 ft (4.9 to 6.1 m) in width and 30 to 40 ft (9.1 to 12.2 m) in length. Maximum dimensions should not exceed 30 ft (9.1 m) in width and 70 ft (21.3 m) in length. If bay length is more than 70 ft (21.3 m), two deck panels can be bolted together.
2. Bay sizes should not vary from floor to floor, so as to avoid modification of the forms. In high-rise buildings where bay sizes changes are inevitable, bay widths should remain constant for at least 6 to 8 floors.
3. Columns and/or walls should be aligned to avoid adding shims. The addition of shims reduces the carrying capacity and adds more time for installing and removing of the jack bracket system.
4. Deep spandrel beams and cross beams between intermediate columns should be avoided. Spandrel beams should be 14 in. (355.6 mm) deep for economical use of this system. Deeper spandrel beams require extra shoring which increases the cost of the system and slows the progress of moving forms from floor to floor. Also, in the case of flat slabs, drop panels around the column should be avoided.