Seawalls & Coastal Defences

Precast Concrete Seawalls & Coastal Defences

Our bespoke precast concrete structures won’t hurt either the planet or your bank balance. Through cutting-edge self-healing technology, we can slash the carbon footprint of your construction, extend the life of your structures, and save you a lot of money in the process.

 

Traditional sea walls – a trade-off between humans and the environment?

According to Ordinance Survey, Great Britain has over 11,000 miles of coastline. But that number is shrinking rapidly.

The sea that surrounds us is both a precious resource and a terrible threat. It constantly nibbles at the coast, and during storm surges it has been known to wipe out entire towns and settlements.

To make our coasts safe places for people to live and work, we need to shore up existing infrastructure and build new defences. The big challenge for modern construction is doing this in a way that doesn’t hurt fragile marine environments.

 

Concrete coastal defences – a necessary evil?

Concrete structures are vital to protect our towns and cities from flooding. However, they come with a lot of problems, including:

Decaying infrastructure – Sea defences take a lot of punishment from our wild weather and stormy seas. This means they need constant repair – which costs a massive amount of money (concrete repairs are estimated to cost the UK £200bn every year). It also pours hundreds of thousands of tons of carbon into the atmosphere.

Corrosion – Corroding concrete is terrible for marine habitats. For example, it can raise the pH of surrounding waters, making it impossible for native wildlife to thrive. Corrosion also adds to the maintenance issues mentioned above.

Carbon footprint – Standard concrete mixes have a huge carbon footprint – the cement used in standard concrete accounts for about 8% of the world’s total CO2 emissions.

Because of all this, building sea defences can feel like a trade-off between the safety of coastal populations, a stable economy, and thriving, healthy seas.
But it doesn’t have to be. We are working hard to bring bespoke, best-of-both-worlds solutions to the beaches of Britain.

 

Resilient, long-life concrete

The majority of the carbon in concrete comes from cement. In theory, cement-free concrete is, therefore, a great way to slash construction’s carbon footprint. However, removing cement from concrete can make it even less durable – resulting in an even greater need for repairs. Back to square one.

To make your cement-free concrete as resilient as it should be, you need to add something else. Some companies use accelerators and plasticisers. However, these also come with environmental downsides. Instead of these chemicals, our Sensicrete mix uses Basilisk – a bio-based self-healing additive.

 

How does self-healing concrete work?

Basilisk is a bio-solution that produces calcium carbonate (limestone) that naturally heals cracks in concrete as they appear.

Microbes in the Basilisk mixture lie dormant in our precast concrete until the concrete cracks.

When cracks appear, the microbes are exposed to water and oxygen. This activates them, and they begin producing calcium carbonate.

They move through the crack, depositing calcium carbonate as they go. The crack is quickly sealed with limestone, and the microbes go dormant once again.

By healing cracks as they appear, Sensicrete structures need fewer repairs, are much more resilient, and have a much longer working life. Best of all, its green credentials will help government departments like the Environment Agency to meet their net-zero carbon goals.

 

Giving marine life a helping hand with biomimicry

As well as helping the planet and your bank balance with self-healing technology, our Sensicrete structures also provide much-needed habitat for endangered wildlife.

Sensicrete precast concrete is perfectly engineered to work with coastal environments. They are designed to mimic the shapes of nature. This biomimicry turns them into ‘living structures’, which creates vital habitat in which marine life can thrive.

Our eco-engineered structures adapt to their environments. They are chemically balanced, so submerged concrete won’t damage coastal habitats, and their self-healing abilities work in perfect harmony with nature.

The result is long-lasting, hyper-resilient structures that protect coastal communities and give the environment a helping hand.

 

Marine exposure zones

We combine our retaining wall experience with world-class research to manufacture bespoke precast systems that suit their environment.

Splash zone – concrete is above the tidal zone and subject to seawater spray
Tidal zone – concrete that alternates being wet and dry in tidal locations
Submerged zone – concrete is constantly immersed in seawater

The maintenance of coastal flood defences is time-consuming and expensive. New concrete structures will minimise the amount of resources needed by the EA to manage these assets.

 

Sea-defence services

• We provide coastal defence products that meet all relevant structural standards and exposure classes, including BS 8500 & BS EN 206.
• Off-site manufacturing, which reduces on-site delays and speeds up construction time. Our off-site manufacturing helps you to get more done quicker, using fewer resources.
• Made-to-measure products. Our precast products are eco-engineered to fit the project needs.
• Marine concrete. Lowering the pH of concrete brings it closer to that of salt water. This enables our submerged structures to exist in harmony with marine environments and encourages marine organisms to use sea defences as a habitat.
• Biomimicry design. Our structures are eco-engineered to mimic natural reef topography. This creates valuable habitats for endangered wildlife.
• Corrosion prevention/protection. Our self-healing technology extends the life of your structure and massively reduces maintenance costs.
• Low carbon footprint. Reduced CO2 in structures is rapidly becoming not just desirable, but demanded. Reduced carbon concrete like ours is leading the way towards what will soon become an industry standard.
• Structural health monitoring. We use MotionWall to monitor your structures and nip impending issues in the bud.

 

Coastal defence systems

• Seawall
• Biomimicry blocks
• Bio-engineered rock armour
• Canewdon block
• Concrete revetments
• Sheet pile cladding
• Concrete pile caps
• Breakwaters
• Tide pools
• Steps & Slipways