Our underwater concrete is specifically designed to allow pouring through water. Due to its high density, our underwater concrete mix is essential for installations below the waterline and offers the same hardening time as in dry conditions.
To prevent the washout of fines and cement materials in static and flowing water, we have incorporated advanced anti-washout properties in our concrete for underwater use. This also helps to mitigate the risk of washout and minimise disruption during installation.
Ideal for marine structures, bridge foundations, and other submerged builds, it delivers exceptional performance and long-term durability in harsh conditions. Prestigious projects already using our cutting-edge product include Leeds Train Station, Canary Wharf, and the Eden Viaduct.
Explore the full range of our innovative underwater concrete mixes below. For more information, please speak to our experts.
What applications can underwater concrete be used for?
Our underwater concrete has been developed in partnership with Sika® . We’ve added their UCS Pak (a powdered underwater/anti-washout admixture) for easier placement. The mix is suitable for any project where concrete needs placing below a waterline, including:
Marine construction
Underwater elements of bridges
Water industry structures
Benefits of concrete that sets under water
First and foremost, underwater concrete is an unrivalled material where concrete needs to be placed and set below water, like submerged bridge foundations. The forward-thinking material also offers:
Below water construction requires specialist concrete with a track record of performance. Heidelberg Materials is a trusted supplier of high-quality, high-durability underwater concrete solutions for submerged projects across the UK.
Take a look at some of the projects we’ve supplied these concrete mixes to.
Sea Defences, Dawlish
We supplied a range of complex concrete mixes, including an underwater concrete mix, to deliver vital coastal protection works at Marine Parade, Dawlish, Devon.
Heidelberg Materials worked with the Environment Agency to provide specialist underwater concrete to complete a bridge protection project in Carlisle, Cumbria.
Heidelberg Materials is a member of the Quality Scheme for Ready-Mixed Concrete (QSRMC) and all our underwater concrete products carry this certification.
From the experts: Underwater concrete
“We engaged with the Network Rail engineering team to develop a bespoke solution to overcome complex placing difficulties and strict environmental controls.
“In less than 40 hours, the technical team had designed and tested an antiwashout, self-compacting concrete ready for the remedial works. The success of the material relied on concrete admixture technology to overcome the challenging engineering requirements.”
Terry Balmer, Technical Manager at Heidelberg Materials UK
“These vital repairs have helped to make the viaducts safe to keep passenger and freight train moving on the West Coast mainline.”
Craig Jackson, Works Delivery Manager at Network Rail
Concrete volume calculator
Use our ready-mixed concrete calculator to select the best concrete for your project and work out the volume you require.
SmartRock wireless concrete sensors monitor temperature and strength gain every 15 minutes for up to 60 days, providing real-time data that can help you save time, money and CO2 with no need for test cubes and no waiting for results.
Underwater concrete is engineered so that it can be poured through water. It’s designed to meet the needs of installations below the waterline, thanks to its high density.
How long does underwater concrete last?
How long underwater concrete lasts depends on several factors, including mix type, installation quality, and environmental conditions. Generally, if it’s designed and placed effectively and properly maintained, it should last between 50 and 100 years.
Does concrete get stronger or weaker in water?
If concrete is hydrated effectively, it can get stronger. So, in certain conditions, underwater concrete can have more strength than concrete used on land.
How to place concrete underwater without losing quality or experiencing washout?
Our underwater concrete is formulated to be cohesive and flowable. This ensures it can be pumped or tremie-placed without segregation, even in flowing or turbulent water conditions.
For more details about concrete with free-flowing properties, please explore our self-compacting concrete range.
Is underwater concrete durable in marine or corrosive environments?
Yes - we have engineered our underwater concrete to withstand harsh environments, including saltwater and chemical exposure, to provide long-lasting durability and structural integrity.
Where can I buy an underwater concrete mix that is bespoke to my project’s requirements?
If you’d like confidence that your underwater concrete mix meets the specific needs of your project, contact our team. We can tailor mix designs for particular water depths, load-bearing requirements, and environmental conditions.
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