Concrete Sensors: A Technology Still in Its Infancy
Under ideal situations, concrete’s psi strength depends a lot on time. Since ideal situations are few and far between, let’s take a look at a young technology that’s taking its first steps at saving contractors time and money.
Contractors can utilize a concrete sensor to gain inside knowledge of what exactly is happening in their concrete, like a health monitor or a Fitbit stuck inside producing vital readouts of the inner workings of the mix reporting on temperature, and analyzing data to estimate maturity levels.
The placement of a concrete sensor device is traditionally anchored or tied to the reinforcement in an array providing data back to contractors. This data can then be analyzed, and a few conclusions can be estimated based on the results. Similar to the seemingly uncountable sensors utilized in today’s modern vehicles, the concrete sensor works by detecting data and sending it to a computer for analysis. Where the vehicle sensors grab information on temperature and pressures (and more) to a more centralized “brain,” the concrete sensor works in a similar fashion. However, the technology is still young in construction.
“We obviously feel that there should be more sensors, we think it’s not only an opportunity to improve quality, but more importantly, you can use the data to move faster, and become more efficient,” says Brendan Dowdall, director of concrete sensors at Hilti. “There’s a lot of opportunity for growth and improvement, both on the technology and on the customer side.”
Dowdall began working with concrete sensors back in 2015 co-founding a startup company focused on sensor technologies. They finally addressed the market two years later and were acquired by Hilti in the March of 2020— roughly a week before “the shutdown.”
One of the biggest changes Dowdall has seen has been within the hardware industry. Originally, if you wanted to build hardware (i.e. a concrete sensor), you would have to become a silicon manufacturer. The last few decades have seen more standardization of how hardware components are manufactured. “At the risk of oversimplifying it,” he explains, “it’s a little like buying off the shelf. Then, it’s up to you (he means the manufacturer here) to sort of put those parts and pieces together.” This moves the burden of expertise away from manufacturing electronics to implementation. These changes adjusted the question from how to manufacture, how to scale manufacturing or the development of high-tech hardware in an economical way towards the market and customer side. For Dowdall, it was now “can we identify a problem that we can address…with a minimum viable product and then in a scalable way. That was the enabling event that got us into it and made it seem reachable as a startup.”
Throughout the years, Dowdall’s team had a number of hurdles to figure out, like the engineering to protect the electronics, electrical issues in how to get wireless signals through the concrete, as well as the design on how to attach it to rebar. And, of course, how to turn it on.
“One of the innovative things, I think, was use a photosensor to turn the sensor on.” Hilti’s concrete sensors (the HCS-T2, HCS-TH1, and HCS T1) are initialized when a contractor takes the product out of the package, essentially putting the device into a state of readiness. Then, once covered by concrete and returned to the dark, the sensor begins capturing data.
As one of the first companies to introduce a fully wireless sensor on the market roughly six years ago, Giatec’s Aali Alizadeh, CTO and co-founder at Giatec, started in civil engineering and materials. Over the past decade, the company has been leading towards technology development and product design. “We’ve always stayed true to our core value proposition of removing the hassle from jobsites,” says Alizadeh. “Construction companies, technicians, and labs want to get things done as easily as possible.”