Physics brains take Bam's concrete testing up a notch

Key Facts

BAM Nuttall is working with new start- up company Converge to develop new concrete sensor technology.

This technology will assist in defining the optimum curing rates for concrete and will ultimately lead to significant savings in time on BAM Nuttall projects. This can be translated into programme efficiencies and major productivity gains.

Article - Daniel Kemp, Construction News

Bam Nuttall is working with a tech start-up to develop new concrete sensor technology – and is already seeing results on a project in London.

Each sensor has a unique QR code to identify it

Each sensor has a unique QR code to identify it

While there is plenty of innovation going on within the construction industry, sometimes a fresh pair of eyes from outside the sector can present a solution nobody had thought of.

This is the case with Converge: a tech start-up that is working with Bam Nuttall on new automated sensor technology.

“We started Converge one-and-a-half years ago,” says co-founder and CEO Raphael Scheps. Mr Scheps and fellow founder Gideon Farrell come from a physics background, rather than construction, and hadn’t worked in the industry before.

“We were looking at different kinds of pressure gauges and other sensors, which in construction are often manual or time-consuming to operate. So we thought that if we could automate them, there could be a big gap in the market.”

The sensors are placed into the concrete and wired to nodes

In particular, the firm looked at the practice of concrete testing and saw an opportunity. Innovation cubed Currently, cubes of concretes are taken from pours and stored, before being tested for strength later to determine when formwork and shuttering can be removed.

The Converge system automates the process, with a sensor placed in the concrete that knows when the concrete has reached the required strength. “We embed the sensor into the concrete and attach it to a node nearby to activate it,” Mr Scheps says.

“The temperature probe goes in the concrete wherever they are monitoring strength. That cable is run to one of our nodes and plugs in quite simply. There are multiple nodes dotted around the site which all speak to one another, and they transmit data across their own mesh network and to a hub.”

In the case of the work being done by a Taylor Woodrow / Bam Nuttall JV at the Victoria station upgrade, the hub is located above ground at the top of a shaft. That hub has its own internet connection and pushes the data to Converge’s servers.

Nodes are placed around the site to collect data

A hub collects all of the data from the nodes and uploads to a server

Each sensor also has its own unique number with a QR code attached that can be scanned using a smartphone, enabling the user to register it. That number can then be traced and renamed as appropriate, to show where the sensor is located.

Real-time data

The concrete’s temperature and strength in N per mm sq are then displayed in real-time on the online platform – with a text automatically sent to workers on site when the required strength is reached, allowing shutters to be removed.

“We’re suddenly able to do some interesting analysis on sites and optimise how they work”

Raphael Scheps, Converge

The sensors are being used on more than a dozen sites in the UK so far, including at Victoria station. Taylor Woodrow / Bam Nuttall site engineer Michael Greenway says the system is “massively helpful”.

“It allows me to see when I can strike my shuttering and formwork,” he says. “That massively reduces my strike times – we managed to strike a piece of formwork the other day in seven hours as opposed to the usual 12.”

The other interesting aspect is the sheer amount of data being collected. Mr Scheps says Converge has collected more than four million data points so far. “No-one’s done that before and it means we’re suddenly able to do some interesting analysis on sites, and optimise how they work,” he says.

The sensors are being used on more than a dozen UK sites

Bam Nuttall head of innovation Colin Evison says the technology has helped speed up the firm’s work. “It hopefully gives us improvement on this project, as we’re not waiting for concrete to strengthen unnecessarily and staff can be doing something else more appropriate,” he says.

“Our next project in London, in summer, in a tunnel environment – we have data of previous work now.”

New applications

Mr Evison says the firm is already exploring other uses for the sensor technology, as any kind of sensor can be attached to the nodes.

“The concrete solution was quite easy and is prevalent on a lot of sites – pH testing as a natural progression”

Colin Evison, Bam Nuttall

“This is an initial solution, but we’re investigating others, like a pH sensor,” he says. “Bam Ritchies, for example, has to treat a lot of wastewater on site. When they’re using CO2 to treat the water they have to keep doing a cycle of treating and testing the water.

“We can use the sensors to automate the process and leave the water in treatment, and be notified automatically when it is ready. The concrete solution was quite easy and is prevalent on a lot of sites; testing is a natural progression.”

Information on temperature and strength can be viewed in real time

For Converge, Mr Scheps says the applications are potentially “vast”.

“We could monitor salinity, pressure, humidity, dust, air quality and many more,” he says. “A lot of data in BIM platforms is theoretical – we’re collecting real data and bridging that gap from the theoretical.”

It’s a simple but very effective solution that is increasing productivity on Bam’s sites, with further applications to come. And it’s an example of people from outside the industry developing a solution that disrupts and improves the existing process.

It’s about changing the way it’s always been done – a sign of things to come in construction.