Hidden beam is a reinforced concrete beam, also called concealed beam provided within the depth of supporting slabs. So, the depth of hidden beam is the same as slab depth. Concealed beams are popular and form an essential part of modern reinforced concrete framed structures.
The design of hidden beam is the same as conventional beam, but its depth is restricted and should not be greater slab thickness. So, it may be required to increase reinforcement ration and width of the beam to overcome this restriction to a certain degree.
Purpose of Hidden Beam
- It is used to help disperse loads imposed on the slab for example weight of brickwork masonry wall.
- It allows to use greater span for the slab.
- Hidden beams are provided exclusively for architectural aesthetic purposes in the building interior.
Advantages of Hidden Beams
- It saves on floor height clearance.
- Hidden beam saves cost of formwork, labor and materials.
- It creates an acceptable aesthetic appearance which permits for efficient interior space partitioning.
- Concealed beam clears the way for horizontal electromechanical ductwork.
Disadvantages of Hidden Beam
- The disadvantage of hidden beam is that it has considerably low ductility due to height reinforcement ratio which is provided to compensate for depth restriction specifically at column connection.