Difference between Ribbed Slab and Solid Slab
Slabs are actually structural members made for floors and roofs in buildings which may be formed of solid thickness or ribbed with ribs running in one or two directions.
About Slab: Slab is a useful element which is made to create flat and useful surfaces like floors, roofs and ceilings of a building. It is a horizontal structural component with top and bottom surfaces parallel or near so. Commonly these slabs are supported by walls, beams, columns or the ground. The depth of a concrete slab floor is very small similar to its span.
These slabs may be solid of uniform thickness or ribbed with ribs running in one direction or two directions or waffles.
Ribbed Slabs: These types of slabs are slabs cast completely with a series of closely spaced joist which in turn are supported by a set of beams. The main benefit of ribbed floors is the lowering in weight achieved by removing part of concrete below the neutral axis. This creates this type of floor economical for buildings with a long span with light or moderate loads.
Solid Slabs: Solid slabs are completely customizable concrete slabs of varying width, length and thickness which can be cast with specially inserts to lift, mounting or connecting hardware. These slabs of uniform thickness can be one-way or two-way:
• One way slab: When a slab is supported on all four sides and the proportion of long span to short span is equal or may be greater than two, it is definitely one way slab. The load on this slab is carried by the short span in a direction but the main reinforced bar and distribution bar in transverse direction. Example: Verandah Slab, Cantilever Slab etc.
• Two Way slab: When a slab is supported on all four sides and the proportion of the long span to the short span is less than 2. It is considered as two way slab. The load on this slab is carried by both the short span and long span though the greater amount of load is carried by the shorter span. Example: Slab used in multistory building.