By Marchant Sevenster
Reputable concrete repair contractors will have strong and longstanding partnerships with leading manufacturers and suppliers of concrete repair materials. This is among the many benefits of only engaging a specialist to provide concrete repair and maintenance services.
Skilled and experienced concrete repair contractors have been approved by concrete repair materials manufacturers and suppliers to apply their products. Achieving this status is no mean feat. To become an approved applicator entails meeting very strict criteria. These differ from one manufacturer and supplier to the rest. However, all reputable suppliers and manufacturers of concrete repair products will insist that approved applicators have met one fundamental requirement. This overrides all the others. Concrete repair contractors must undergo regular training in the correct application of their concrete repair systems.
Therefore, you are assured that the concrete repair contractor that you have engaged has thorough knowledge of the repair system. They know the product inside out. This means that it will be applied correctly the first time round without delays, impacting repair costs and time. Also consider the effect of delays on business operation. Bear in mind that most concrete repairs are undertaken in operational areas. Just as importantly, intimate knowledge of the repair system facilitates an application of exceptionally high quality. Therefore, this work can be guaranteed for the maximum term available. This provides you with further peace of mind that your project is in the best hands. All too often, concrete repairs have failed due to poor workmanship quality. This, alone, points to the need for asset owners to do thorough due diligence before appointing a concrete repair contractor. The workmanship of your contractor has a large part to play in the success of your concrete repair project.
Safe concrete repair application
Just as importantly, concrete repair contractors are skilled in safe concrete repair systems application. Mines and other heavy-regulated industries place health and safety first. They are among the biggest users of professional concrete repair and maintenance services. Bear in mind that they are bound by law to ensure that their facilities are safe. Validating the structural integrity of buildings and production infrastructure is part of this requirement. Refer to https://www.gov.za/documents/mine-health-and-safety-act and https://www.gov.za/sites/default/files/gcis_document/201409/act85of1993.pdf.
Furthermore, proactive concrete repair and maintenance ensure operational efficiency. It mitigates downtime and saves in large repair cost further down the line.
Commercial buildings usually also have to stay operational when repairs or maintenance are being undertaken. Facilities managers will, therefore, insist that their concrete repair and maintenance contractors have a robust health and safety track record.
Part of the value offering of a skilled and experienced concrete repair contractor is the ability to provide safe solutions. This is demonstrated by strict adherence to health, safety and environment protocol [https://dekracertification.co.za/revisions/Produktblatt_ISO_45001_EN_web.pdf]. Hindle Mason Projects, for example, has continuously achieved Five Shield Dekra ratings for its health, safety and environmental performance. This is complemented by the company’s ISO 9001: 2015 Construction Quality Assurance Programme [https://www.iso.org/standard/62085.html].
Concrete repair contractors keep pace
Concrete repair contractors keep pace with the latest developments in concrete repair products. This is considering their strong partnerships with leading manufacturers of concrete repair products. These large companies, many of which operate globally, invest heavily into research and development (R&D). Innovation is key to success in a very competitive market. In 2022, the global concrete repair mortars market, for example, was valued at US$2,83-billion. It is anticipated to grow to US$6-billion by 2031. This is according to https://www.skyquestt.com/report/concrete-repair-mortars-market#:~:text=Concrete%20Repair%20Mortars%20Market%20Insights,period%20(2024%2D2031).
A significant driver of this growth is the ever-growing demand to address structural defects that are caused by many factors. Among others, these include temperature variations; water ingress; and corrosion. Local infrastructure networks are subjected to the same harsh conditions. Repair mortars serve as protective barriers. This prevents further degradation and even extends the lifecycle of concrete structures.
Meanwhile, the development of advanced mortar mixes by leading chemical companies has enhanced material properties. This had made them more effective and versatile.
These companies are also investing heavily into R&D of more sustainable concrete repair products. This focus spans the use of low-carbon raw materials through to solutions that reduce environmental impacts during application.
Concrete repair innovation
There is no end to concrete repair materials innovation. Reputable concrete repair contractors, therefore, ensure that they are always at the cutting-edge of technology.
There is a need to constantly improve concrete repair materials. This is considering the costs involved in repairing and maintaining concrete structures. The UK, for example, spends £40-billion per year on the repair and maintenance of its ageing infrastructure. Meanwhile, the US needs more than US$3-trillion over five years to raise the overall quality of its infrastructure. It is currently in poor condition. An alternative to traditional design must be found. This will continue to drive R&D into better ways of constructing, maintaining and repairing concrete structures.
Experienced concrete repair contractors
Equipped with this knowledge, skilled and experienced concrete repair contractors can select the best concrete repair system for given applications. This is based on many factors. They include strength; durability; coefficient of thermal expansion; permeability; low-drying shrinkage; chemical properties; and modulus of elasticity.
Most concrete repair works
Most concrete repair and protective works rely heavily upon bond and compressive strengths. The strength of the base material and that of the repair system need to be almost the same. Oftentimes, the strength of the repair materials should be slightly higher than that of the base material. Bond and compressive strength are key considerations when determining whether damage is structural or non-structural in nature. This knowledge enables concrete repair contractors to choose a cost-effective, durable and structurally suitable repair solution.
Durability of concrete repair materials
Durability of concrete repair materials is another very important consideration. This ensures that concrete repair materials will be able to withstand the forces to which the defected structure are exposed. They need to adequately resist chemical attack and form of energy, such as ultra-violet rays and heat. Certainly, surface preparation also plays an important part in ensuring the durability of concrete repair materials. This is in addition to being suitable for the intended purpose and environment.
Concrete repair materials’ thermal compatibility
Concrete repair materials’ thermal compatibility is another important consideration. The coefficient of thermal expansion needs to be similar to that of existing concrete. This will ensure that undue stresses are not transferred to the bonding interface or substrate. Thermal incompatibility may cause failure either at the interface or within weaker material, particularly overlays.
Concrete repair materials’ drying shrinkage
Concrete repair materials’ drying shrinkage properties are also another important consideration. Bear in mind that shrinkage has already occurred in the existing structure. Therefore, concrete repair materials must have the lowest possible drying shrinkage properties. This will ensure that there is no failure between the bond of the new repair material and underlying existing concrete surface.
Concrete repair materials’ permeability
Concrete repair materials’ permeability must also be low to prevent the penetration of aggressive substances. They include carbon dioxide, water, oxygen and industrial gases and vapours that corrode reinforcement bar. Generally, the higher the compressive strength of concrete, the lower the water-to-cement (W/C) ratio. Concrete with a lower W/C ratio is less permeable.
Concrete repair materials’ modulus
Moreover, concrete repair materials’ modulus must be similar to that of the existing concrete. Concrete repair materials with a lower modulus are suited to non-structural repairs. This is because they help to relax the tensile stresses induced by restrained drying shrinkage.
Concrete repair materials’ chemical properties
Another important factor is concrete repair materials’ chemical properties. An alkaline environment of a pH close to 12 is ideal for protecting reinforcement bar from corrosion. Otherwise, additional protection for the existing reinforcement bar will be required. Such interventions include cathodic protection. Refer to https://www.concreteconstruction.net/how-to/repair/cathodic-protection-an-emerging-solution-to-the-rebar-corrosion-problem_o. Coating the reinforcement or treating concrete surfaces are also options available to reduce corrosion.
Concrete repair specialist
Hindle Mason Projects is a concrete repair and corrosion/erosion protection specialist.
As such, we are approved applicators of:
- SprayLock Concrete Protection [https://www.concreteprotection.com/]
- StonCor Africa [https://www.stoncor.co.za/]
- ABE Saint Gobain [https://www.abe.co.za/waterproofing-product-selector/]
- Sika [https://zaf.sika.com/?gad_source=1&gclid=EAIaIQobChMI0fr46-a3hgMV1ZlQBh3AcQOREAAYASAAEgJBK_D_BwE]
- Mapei [https://www.mapei.com/za/en/home-page]
- Bostik [https://www.bostik.com/global/en/]
- Penetron Africa [https://penetron.africa/]
Sevenster is Business Development Manager of Hindle Mason Projects
