During a renovation project in Grasse, our team was called in urgently for the structural repair of a reinforced concrete (RC) beam that had been cut by mistake during demolition work.
This situation posed a significant risk to the stability of the floor and called for a quick, methodical intervention.
Thanks to the involvement of a reinforced concrete structural engineering office, the reinforcement was precisely sized to guarantee the safety of the structure and its long-term durability.
Structural diagnosis and reinforcement study
Once the structural damage was identified, a reinforced concrete structural engineering office carried out a full analysis of the existing beam and the loads it carries.
The study defined a steel structure reinforcement solution, consisting of tying the existing beam to a double UPN 220 steel section system, installed on a twin-beam clamping (moisage) principle.
This technique takes over the structural forces and restores the load-bearing capacity of the damaged beam.
Preparatory work on the existing concrete beam
Before the steel reinforcement could be installed, several preparatory operations were needed.
The first step was to demolish the central part of the reinforced concrete beam, which had already been partly cut during the earlier work.
This operation made it possible to:
- remove the weakened areas of concrete
- expose the existing reinforcement bars
- prepare the substrate for the structural repair
Once the area had been cleared and cleaned, the teams carried out the preparatory work needed for the reinforcement.
Installing the structural reinforcement
In accordance with the engineering office's recommendations, the structural repair took place in several stages:
1. Sealing in the steel bars
Anchor bars were sealed into the existing beam to link the concrete to the future steel reinforcement.
2. Concrete repair
The prepared area was then rebuilt with a non-shrink structural repair mortar, restoring the integrity of the concrete and ensuring good transmission of forces.
3. Installing the twin-beam clamping (moisage) system
The main reinforcement was made by fitting two UPN 220 steel sections on either side of the existing beam.
The sections were fixed with M16 threaded rods passing through the beam, creating a twin-beam clamping (moisage) system that ties everything together and carries the loads effectively.
This technique is particularly well suited to the repair of damaged reinforced concrete beams without needing to demolish the structure completely.
A safe, durable structure
Thanks to this rapid intervention and strict compliance with the method defined by the engineering office, the reinforced concrete beam was made safe and durably strengthened.
This type of work shows how important it is to call on professionals specialising in underpinning and structural reinforcement, particularly when a load-bearing element is accidentally damaged.
Our team regularly carries out structural reinforcement work in the Alpes-Maritimes, notably in Grasse, Cannes, Antibes and Nice, for operations such as:
- repair of reinforced concrete beams
- floor strengthening
- creating openings in load-bearing walls
- installing steel support structures
