How do you reinforce a floor?
Several reasons can make it necessary to reinforce a floor. The need may come from storing loads that are too heavy, from wear of the reinforcement due to rust or fire, or from correcting the consequences of design calculation errors, poorly determined concrete cover during construction, or poor-quality concrete. Cutting floor openings next to load-bearing walls also makes it essential to reinforce the reinforced concrete floor with steel, a guarantee of strength and durability.
Different floor strengthening techniques can be used depending on the layout of the premises and the nature of the materials. Twin-beam clamping (moisage) is one : it consists of bringing together timber beams or concrete pieces to reinforce the floor and tie it back if there is a floor opening. Another method is to embed compact sections by thickening. A last process, known as the « Hermite » method, uses a connected beam as reinforcement together with bonded steel plates, like the technique used to strengthen a bridge. Although this technique offers excellent strength, it is not ideal in the event of fire, because the fire resistance of the adhesive is not optimal.
Reinforcing a timber or concrete floor is not a good solution when the surface is too badly deteriorated. In that case it is better to strengthen the whole structure beam by beam. Starting from what exists, the steel parts of the reinforced concrete must be treated to remove any trace of corrosion and given an anti-rust treatment. Steel beams are then added to reinforce the existing structure.
This combination of concrete and steel offers a double advantage, both economic and structural. The connectors joining the steel structure and the concrete slab reduce the installation cost and ensure a mechanical bond between them for greater strength and less deformation.