Basics in Building Construction

Building Components And Types

Lesson 25 : Form Work

Form Work For Floors

The formwork for an R.C.C. floor consists of a skeleton to receive the concrete. It consists of rows of vertical posts which carry small wooden beams at their tops. The planks for slab are placed on these beams. The boxes for beams are prepared from two sides and one bottom. The vertical posts are suitably supported by lateral supports. Laterals, tapering blocks, base – beams, wooden blocks and struts are provided to make the formwork for floor strong enough to bear the load coming upon it.

The formwork for floor should be designed for the weight of concrete plus some additional load to the extent of 30 percent to provide for labour, storage of materials and equipment. If required the posts should be provided with diagonal braks. The vertical supports should be firmly supported at the bottom. The box for beam formwork is generally prepared at ground level and hoisted and placed in position. When secondary beams are to rest on the main beams, suitable openings at the correct positions are provided in main beams to receive the formwork of secondary beam.