Reinforced Concrete Repair | Technical Projects in Barcelona

Concrete Repair: Much More Than Patching Spalling

Seeing concrete on a beam, column, or balcony crack and spall, exposing rusted steel, is a clear warning sign. A merely cosmetic repair, applying a layer of mortar over the damaged area, is not only ineffective but also dangerous. Without proper diagnosis and protocol, the corrosion process will continue invisibly, and the problem will reappear worse in a short time.

Our role as consulting engineers is to define the "why" of the deterioration and "how" it should be properly repaired to stop the process and restore the structure's safety and durability.

The Hidden Causes of Concrete Deterioration

Concrete protects steel from corrosion thanks to its high alkalinity (high pH). When this protection is lost, the steel corrodes, expands, and breaks the concrete from within. The two main causes of this phenomenon are:

1. Carbonation: It's the most common enemy. Atmospheric carbon dioxide ($CO_2$) penetrates the concrete's pores and reduces its pH, eliminating steel's natural protection layer. It's a slow but relentless process, especially in urban environments.

2. Chloride Attack: It's a much more aggressive enemy. The presence of chloride ions (from marine environments or de-icing salts) destroys the steel's protective layer even with high pH, causing very rapid and localized corrosion.

Our Action Protocol: EN 1504 Standard as Guide

For a repair to be effective, it must follow European standard principles. Our technical project details each step that the executing company must follow:

1. Concrete Preparation: Complete removal of deteriorated and unsound concrete until reaching a sound and rough base.

2. Reinforcement Cleaning: Removal of all rust from steel bars, typically through abrasive blasting, until reaching grade SA 2½. This step is critical and non-negotiable.

3. Reinforcement Passivation: Application of a protective coating (bonding agent) on clean steel to restore its protection against corrosion.

4. Volumetric Reconstruction: Application of structural repair mortar (type R3 or R4) to restore the element to its original geometry and section.

5. Final Protection Layer: Application of a final coating (anti-carbonation paint, water repellents) to protect the repaired area and adjacent concrete from future attacks.

Don't leave your structure's safety to a superficial repair. A prior technical project is the guarantee of a job well done.