Latest / Internet of Things with Fexingo: Connected Devices, Sensors, and Industrial IoT / How IoT Sensors Track Concrete Curing in Real Time
Transcript
- Lucas: Alright, Luna, let's talk about concrete. Specifically, how IoT sensors are now tracking concrete curing in real time on major construction projects. Luna: Concrete curing—that's the chemical reaction where water and cement form calcium silicate hydrate, right? The process that gives concrete its strength. Lucas: Exactly. And for decades, the industry's approach has been surprisingly low-tech. You pour the concrete, you maybe stick a thermometer in it, and then you wait a fixed number of days—often 28—before you assume it's strong enough to bear loads. Luna: But that fixed schedule is wasteful. If you cure too long, you delay the project. If you stop too early, you risk structural failure. Lucas: Right. And the actual curing time depends on ambient temperature, humidity, the mix design—so a one-size-fits-all schedule is inherently inefficient. That's where IoT comes in. Luna: So what's the specific setup? I've heard of companies embedding sensors directly into the pour. Lucas: Yes. Take a startup called CuraSense. They make these small, wireless sensors—about the size of a deck of cards—that you embed in the concrete right after pouring. They measure temperature and internal humidity, which are the two key proxies for the hydration reaction. Luna: And the sensors transmit data wirelessly? Even through multiple feet of concrete? Lucas: That's the clever part. They use a low-frequency radio protocol—similar to what you'd find in some industrial IoT applications—that can penetrate dense material. The sensor sends data every 15 minutes to a gateway on site, which then uploads it to the cloud. Luna: So engineers can pull up a real-time dashboard showing the curing progress. They're not just guessing anymore. Lucas: Exactly. And the payoff is significant. There was a 2025 project in Seattle—a 40-story residential tower—where the general contractor used CuraSense sensors on every floor pour. They were able to reduce the average curing time from 28 days to 17 days, while still meeting or exceeding the design strength specifications. Luna: That's an 11-day reduction per floor. Over 40 floors, that's massive schedule compression. Lucas: It is. The contractor reported a 40 percent reduction in project delays attributed to curing. And because they could pour floors faster, they also reduced labor idle time and equipment rental costs. Luna: I imagine the structural engineers also get peace of mind. Instead of a static calendar date, they have actual data proving the concrete reached 70 percent of its design strength on day 10, for example. Lucas: Right. And that data becomes part of the permanent record. If there's ever a question about the building's integrity—say, 20 years down the line—you have a digital log of exactly how each pour cured. That's a huge liability reduction. Luna: Now, are there any challenges? I'd imagine embedding electronics in concrete that's meant to last decades raises some durability concerns. Lucas: It does. But CuraSense designed their sensors with a long-life battery—they claim a ten-year lifespan—and they encapsulate the electronics in a epoxy that's chemically compatible with concrete. The sensor becomes essentially inert. And because it's wireless, there's no need for external wiring that could corrode. Luna: So after the building is complete, the sensors just stay in place, dormant, but potentially readable later if someone needs to check? Lucas: That's the idea. Some contractors even use the same sensors to monitor the building's long-term structural health—tracking things like temperature gradients that might indicate stress. But for now, the primary use case is during construction. Luna: Let's zoom out a bit. How widely adopted is this technology? Is it still niche, or are we seeing it become standard? Lucas: It's growing fast. A 2025 industry survey by the National Ready Mixed Concrete Association found that about 15 percent of large commercial projects—those over 10 million dollars—now use some form of IoT curing monitoring. That's up from essentially zero five years ago. Luna: And that number is likely to climb as the cost of sensors drops and the ROI becomes more documented. Lucas: Yeah. The sensors themselves cost around 50 to 100 dollars each, and you might use one per 20 cubic yards of concrete. On a high-rise, that's maybe a few thousand dollars in sensors—but the schedule savings can be in the hundreds of thousands. Luna: It's a classic IoT story: cheap sensors, big data, and a clear decision-making benefit. Lucas: Exactly. And this specific use case—concrete curing—is a perfect example because it's a process that was essentially invisible before. Now you have visibility, and that lets you optimize. Luna: If today's conversation gave you something usable, the way these episodes stay ad-free is through listener support. You can find us at buy me a coffee dot com slash fexingo. It's a simple way to keep the show going. Lucas: Yeah, and we really appreciate that. It lets us keep drilling into these specific technologies without worrying about sponsorships. Luna: Alright, back to concrete. One thing I'm curious about: are there standards or certifications emerging for this kind of IoT monitoring? Lucas: There are. The American Concrete Institute recently published a guide—ACI 228.2R—that specifically addresses using embedded sensors for maturity and strength gain. So it's becoming codified. Luna: That's key for adoption. Engineers and contractors need to know that the data meets a recognized standard before they'll rely on it for critical decisions. Lucas: Absolutely. And as more projects adopt it, the data pool grows, which helps refine the models. For instance, CuraSense uses machine learning on their aggregated data to predict curing curves even more accurately. Luna: So it's not just passive monitoring—it's becoming predictive. Lucas: Right. They can tell you, 'Based on the first 12 hours of data, this pour will reach 70 percent strength in 9 days rather than 14.' And that kind of confidence lets contractors plan the next steps earlier. Luna: I can see this becoming standard for any concrete structure where schedule matters—which is almost all of them. Lucas: Exactly. And it's not just high-rises. Bridges, dams, pavements—any large concrete pour benefits from real-time curing data. There's a pilot project on a highway expansion in Texas right now using similar sensors to decide when to open lanes to traffic. Luna: That's a great example. Instead of waiting a fixed 7 days, they can test and open as soon as the concrete is ready, reducing traffic disruption. Lucas: Yeah. And that's the broader promise of IoT in construction: replacing rigid schedules with data-driven decisions. Concrete curing is just one slice, but it's a very tangible slice. Luna: So for listeners who work in construction or civil engineering, what's the takeaway? Should they be looking into these sensors for their next project? Lucas: I'd say yes. The technology is proven, the costs are low, and the ROI is clear. Start with one pour—a test slab or a foundation—and compare the data to your traditional schedule. I think you'll be convinced. Luna: And if you want to learn more about CuraSense or the ACI guidelines, we'll link some resources in the show notes. Lucas: For now, I think we've shown how a simple sensor in a slab of concrete can make a skyscraper rise faster and safer. That's the internet of things in action. Luna: Absolutely. Thanks for joining us.