Measuring the strength of concrete in highways and bridges has traditionally entailed “heavy equipment, extensive labor, and considerable uncertainty,” says Luna Lu, an associate dean and engineering professor at Purdue University who started Wavelogix, the company that makes Rebel Concrete Strength Sensors. The sensors, which are installed on a stretch of road before concrete is actually poured, transmit real-time data about the material directly to engineers’ smartphones, allowing them to ascertain when new construction is strong enough to handle cars or when to shut down a highway for repairs. Earlier this year, the sensors were added to highways in Texas and Indiana, with more states coming soon.

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