Concrete additives ensure that a concrete structure remains waterproof throughout the building’s life cycle

Underground concrete structures, including building foundations and infrastructure, are almost impossible – or at least extremely difficult – to repair retrospectively. The lifespan of these structures must be considered at the design stage. Concrete additives help ensure that concrete structures that are located underwater or come into contact with ground moisture are able to withstand the moisture levels they will be exposed to throughout their life cycles.

The Finnish building industry has strong expertise in concrete construction and the materials used are durable and of high quality. However, a physical moisture barrier on top of the concrete does not last forever. A bitumen layer or insulating film is exposed to mechanical wear, and it ages, hardens, dries, or becomes brittle. The moisture barrier may also suffer damage at the construction stage as a result of contact with an excavator bucket or rock.

Even if great care is taken in the casting of the structures, cracks may appear in the concrete. In many applications, waterproof concrete with a sufficient level of additives and reduced shrinkage is used. Even then, moisture can enter structures made of waterproof concrete through cracks.

‘Concrete with waterproofing additives remains dry, even when the physical moisture barrier is damaged, or cracks appear in the concrete.’ – Sami Soininen, Suomen TPP

Concrete additives offer a peace of mind to designers and developers, allowing them to rest easy in the knowledge that the concrete structures will remain strong and healthy throughout the building’s service life.

 

Crystalline admixture seals cracks and prevents water from entering the concrete

A crystalline admixture reacts with free calcium in the concrete and water and forms crystals within the pores and capillaries in the concrete, thereby blocking the passage of water through the concrete. More crystals are formed by contact with new moisture, eventually pushing the humidity back. This ensures a lifetime of waterproofing for the concrete structure.

Air and water vapour can still be transmitted through the structure, which allows it to breathe. However, water in liquid form cannot pass, which would be necessary for the mechanism of corrosion to start, so the rebar is protected.

As the crystalline admixture is added to new concrete during batching, it becomes a constituent of the concrete. Therefore, it cannot become physically damaged or lose its properties in the way a separate physical barrier could. The additive also seals future cracks in the concrete.

Read more about the applications of CWS Admix® and download a brochure (in Finnish).

 

A revolutionary liquid waterproofing agent sprayed on cured concrete creates a hard and waterproof surface

This liquid spray-on material can be used to strengthen and seal old and new concrete surfaces. It penetrates the top 15-20 mm of concrete and creates a hard, gel-like, waterproof layer in the concrete matrix. The substance also seals future hairline static cracks, should they develop.

A concrete surface protected with this insoluble gel also withstands mechanical strain and vibration, repels dirt, and makes maintenance easy. CWS100® liquid spray-on agent makes a concrete surface as hard as granite. It offers an ideal solution for surfaces exposed to heavy-duty use and rolling, or abrasive, loads, such as harbours, bridges, and car parks.

Apart from its lifetime waterproofing capability and intense chlorides’ ingress arrest, CWS100® has super-fast application. Up to 6.000 m2 can be applied in one day by one worker. This ensures dramatically shorter project times and protects project deadlines and the risk of liquidated damage claims for the contractor.

Read more about the applications of the CWS100® waterproofing and download a brochure (in Finnish).

 

3 tips for designers – carefully selected additive is efficient on the worksite

  1. Read the product’s test results carefully. The manufacturer’s test results help you ensure – and demonstrate to contractors – that the product is designed for its intended use and adequately prevents water penetration.
  2. Select an easy-to-dose product. The more complicated the calculations that are required for dosing the additive, the higher the risk of human error. The CWS Admix® additive sold by Suomen TPP is delivered in 800 gram bags, with one bag needed per cubic metre of concrete. Dosing is easy and no material goes to waste. Less quantity is needed, compared to most other materials, which results in reduced extra weight on the structure.
  3. Make sure that the product does not cause delays on the worksite. CWS Admix® additive does not influence the concrete’s processing or prolong its curing time. Because the concrete does not take any longer to cure, time is not wasted on the worksite.

 

Read more about concrete additives and CWS products (in Finnish).

 


 

Suomen TPP is part of Masino Group. Masino Group consists of companies that specialise in power transmission solutions, hydraulics and filtering technologies, pumps, blowers and industrial maintenance, piping systems, fixtures, welding, soldiering, rock reinforcement technologies, concrete fibres and HEPAC products. Our turnover is about €80M and we employ 180 people. We have operations in Vantaa (in two locations), Ylöjärvi, Tampere, Turku and Tallinn, Estonia.

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