Concrete Repair

Concrete Cancer

Concrete cancer is widespread. It is caused by cracks in the concrete allowing water ingress to the reinforcement. Water, when combined with carbon dioxide from air, chloride from salt near the coast, or Magnasite (a concrete surface finish) will form an acid and attack the reinforcement. Skilled contractors can effect a complete restoration of integrity by removal of damaged concrete, treating or replacing and retying reinforcement and applying a suitably designed concrete mix.

Structural Concerns

Many clients are concerned about the structural integrity of their building. Andersal provides preliminary assessment but use specialist structural engineering consultants and testing where there is a need. We are experienced in concrete strengthening such as carbon fibre reinforcement. We can propose and discuss alternative cost effective solutions with clients, consulting engineers and supplier experts. We know when to economise, and importantly when not to compromise structural soundness.

Latest Technologies

We have a multi-focused approach to concrete repair. We design for a long term solution with less maintenance in the future. We use water repellents such as silanes, surface conditioners such as Dry Treat and Cathodic protection of reinforcement steel where this is economical. Our major suppliers such as SIKA, Parchem, Xypex and BASF recommend us for specialist remedial projects. We protect and eliminate the causes of failure.

Professional Repairs Enhance Asset Value

Andersal has successfully completed hundreds of concrete repairs in all types of structures.

The most common causes of premature deterioration encountered are:

Poor placement of steel in the concrete

This results in inadequate cover around the reinforcement which causes the concrete to crack leading to water ingress, subsequent exposure and contamination with chlorides.

Failed waterproofing: This results in water ingress.

Failed previous repairs.

This in turn is often caused by inexperienced contractors who do not remove all contaminated concrete or sufficient steel, do not prime the steel bars or do not cure the specialised repair mortars. Sometimes only superficial surface patching is attempted. This merely hides the problem for a more expensive repair later

Unrealistically low, fixed-price quotations

This can encourage some contractors to carry out only partial repairs. Less ethical contractors will fail to mention or fix hidden, latent damage discovered during the repair process. Unethical contractors can reduce expense by using less reinforcement, by not tying or welding reinforcement or by using lower grade concrete mix

Andersal also uses water repellents such as silanes, surface conditioners such as ‘Dry-Treat’, buried anode protection for steel reinforcement, rust inhibitors and many other techniques to extend the life of the concrete where this is financially advantageous.

Professional repairs can have a disproportionate impact on asset value. It is important to select a capable contractor who provides sound advice and competence.

Andersal repaired the Garden Island Dry Dock and enhanced the longevity with Silane coatings and buried anode protection system.