Reinforced Concrete Roof Slab Thickness

For determining moments shears and reactions of such slabs.

Reinforced concrete roof slab thickness.

Exact specifications vary but most concrete roofs are several inches thick. A concrete roof is exactly what it sounds like. A solid slab of concrete capping the top of your house. Such slabs left unconnected to walls caused many deaths in the 2005 quake from school roof collapses.

Minimum reinforcement is 0 12 for hysd bars and 0 15 for mild steel bars. According to the 1995 aci code all two way reinforced concrete slab systems including edge supported slabs flat slabs and flat plates are to be analyzed and designed according to one unified method such as direct design method and equivalent frame method. Plan view of a reinforced concrete pitched inclined slab. The maximum diameter of bar used in slab should not exceed 1 8 of the total thickness of slab.

Steel reinforced slabs typically between 100 and 500 mm thick are most often used to construct floors and ceilings while thinner mud slabs may be used for exterior paving see below. Thickness of the slab is decided based on span to depth ratio specified in is456 2000. Slab reinforcement cantilever reinforcement slab thickness roof apex reinforcement example of a 1. For flatwork such as slabs on grade and driveways a minimum thickness of four inches is required but increasing the thickness to five inches can add nearly 50 percent to the load bearing capacity.

A concrete slab is a common structural element of modern buildings consisting of a flat horizontal surface made of cast concrete. For example the florida based company hurricane proof systems offers a 7 inch 18 centimeter slab of concrete in three layers. Reinforced concrete slabs are heavier and generate higher seismic forces in an event. In general 6 inch 150mm slab thickness is considered for residential and commercial buildings with reinforcement details as per design.

Methods used for finding slab thickness varies for different types of slabs. 6 mm 8 mm 10 mm 12mm and 16mm. Thickening the structure along the perimeter by another will serve as an integral footing adding strength where the loads are heaviest.