Question

1. Design the formwork for a suspended concrete roof slab 8 in. thick. Sheathing will be 3/4-in Ply form (structural 1), while 2 x 4 in. Southern Pine will be used for the joists. Stringer will be 4 x 4 in. Southern Pine. Assume that all members are continuous over three or more spans. Commercial 4000-lb shores will be used. It is estimated that the weight of the formwork will be 10 lb. /sq. ft.

Maximum deflection of form members will be limited to 1/360. Use the minimum value of live load permitted by the American Concrete Institute (ACI).

Determine appropriate joist spacing, stringer spacing and shore spacing. Illustrate your answers in clearly labeled plan and elevation sketches of the formwork.                            

Answer 1