Like wet and dry cycles, chemical changes provoked by carbon in ambient air and melting salts, the freeze and thaw cycles are types of external elements that strain concrete structures. Once problems are visible, quick action is needed.
A company that listens to you
Dumoulin & Associates intervenes proactively to maintain your concrete structures and ensure longevity.
Before taking on a project, an expert evaluation is important in determining the source of the problem, the extent of the damage, and the possible solutions.
One of our senior engineers, a member of the Ordre des ingénieurs du Québec or Professional Engineers Ontario, as the case may be, will perform the evaluation. Different tools and tests may be used to reach a conlusion:
- Mechanical survey
- Core drilling
- Specification tests
- Determination of chloride ion concentration
- Carbonation testing
- Evaluation of the residual strength of the reinforcing steel
Our engineers’ involvement help determine all the factors to account for in order to carry out lasting and high-quality repair work.
The care taken to prepare the surface is the determining factor for the project’s success. The sections of degraded concrete must be removed down to the undamaged concrete surface, which must then be well cleaned. Then, a bonding agent is applied in preparation for the new concrete.
All proper concrete repair start with proper surface preparation!
It is necessary to apply a corrosion inhibitor to eliminate rust on the reinforcing steel. The minimum thickness of the coating must be respected as part of the concrete restoration plan because the reinforcing steel would need replacement if they are too corroded.
The application of sacrificial anodes can also be considered. This new technique requires installing anodes specifically developed to corrode before the reinforcing steel, thus protecting the concrete structure.
Once the surface is prepared and the bars reinforced, where applicable, it is time to apply the repair product, which must be carefully selected based on the type of repair intended.
This choice will depend on the conditions the work will be exposed to and the repair itself. It is equally important to note that the installation of a waterproof form is often necessary in the case of deep repairs, as well as to shape the concrete repair.
The following concretes and mortars are often used:
- Polymer mortars with controlled shrinkage
- High early strength concrete
- Self-levelling concrete
- Self-compacting concrete
- Refractory concrete
- Quick-setting concrete