Behavior of a one-way slab connected to a cantilever

In this civil engineering article, detail information is given on the behavior and the reinforcement concerning a one-way slab that is attached with a cantilever.

If the first slab belongs to a two-way slab both the behavior and the reinforcement rules are uniform.

The bars comprise of the primary and the secondary reinforcement essential for the static calculations. They are arranged in sections of the lower and upper slab surfaces and they defend the strength of the structure against the primary loads established by the regulations.

However, besides, the primary loads there exist immeasurable loads which lead to less in-tense, secondary stresses. These are effectively transferred in areas with reinforcement whereas in all other areas they lead to development of cracks.

These type of stresses, devoid of concrete’s drying shrinkage, belong to differential deformations resulting from abrupt differential stressing, e.g. the position of building materials upon a section of a slab, primarily though they are deformations originated from earthquake forces.

The cracking can’t impact the strength of the structure but it produces serviceability and aesthetic problems. The control of cracking can be done with supplementary light coherence reinforcement that is arranged at the lower and upper surfaces of the slab in the areas that remain unreinforced.

Also Read: Minimum thickness of concrete slab

Note - The coherence reinforcement is equivalent to the surface reinforcement that is essential for all regulations only for resisting cracking. A large reinforcement cover depth should be provided when adverse environmental conditions exist all through the lifecycle of the structure.

In the upper floor slabs and normally, throughout the construction phase, in all weather-exposed slabs it is almost obligatory to provide a light wire mesh in order to prevent the cracking mainly resulting from the weather conditions existent all through the building’s construction.

The coherence reinforcement is arranged with a light industrial wire fabric reinforcement e.g. Τ131, that is set at the lower surface of the cantilever slabs and at the upper section of the slabs’ span without any primary reinforcement.