Concrete Sensors - Saving Time and Money

Throughout our 1% Better Every Day Mission we are exploring better, more sustainable solutions for our construction projects. Whilst our key aim is to cut carbon emissions, many sustainable solutions also help maintain a more efficient site, helping to save both time and money.

Concrete Cube Testing

A new technology has recently been brought to our attention which involves using sensors imbedded into concrete to record the concrete’s strength and maturity. Traditionally to identify whether concrete has reached its maturity, and is therefore ready to have the propping removed, concrete cube tests are conducted. These tests measure the compressible cube strength of the concrete to ensure it meets the required strength specified for the building’s design. During a concrete cube test various samples of concrete are taken from the concrete poured onto site. These samples are then placed into cube shaped moulds and are appropriately stored as per requirements. After a period of time the cubes are then tested to gauge if they have yet reached maturity, usually one is tested after 7 days, 14 days and after 28 days – although this can vary.

Whilst the concrete cube method has been used across building sites for decades and is a requirement to ensure cracking doesn’t occur on site, the method is not without its flaws. The success of cube testing is heavily reliant on the samples being a true representation of the concrete used on site. For example, the concrete should be a good cohesive mix and is usually sampled after the first meter has been poured. If the concrete is not laid sufficiently inside the cube or appropriate concrete has not been used (i.e. – it was not fresh when moulded) the samples may fail and will not be an accurate representation. If this occurs, expensive investigations may then need to occur which can massively slow down progress onsite and will incur further costs and material wastage.

Concrete Sensors

The new concrete sensors aim to mitigate the need for concrete cube testing by providing a much more accurate representation of when concrete has reached its maturity. The concrete sensors are melted into the concrete being laid and connected to a transmitter which collects data wirelessly. To determine the concrete’s maturity the temperature is taken and transmitted back to the cloud which in turn uses software to calculate the maturity and resistance based on these readings. As these readings are in real time, they are extremely accurate and enable sites to move onto the next stage of a build without the delay of waiting for cube testing, which may not be accurate.

This system is a much more efficient way to measure concrete’s maturity and is particularly useful in complex structures with multiple storeys that require efficient cooling to guarantee product control. Sensors can also be used to detect changes such as cracking or weakening in the concrete’s properties, allowing for early intervention. This helps prevent problems later on and greatly reduces material wastage, keeping carbon emissions down.

The SOLID team are extremely interested in technologies which promote sustainability and efficiency on site. Our 1% Better Every Day Mission aims to discover ways to implement such advances into our work wherever possible. If you have come across ground-breaking technological advances do contact the team to pass on your knowledge.