Engineers at Purdue University have developed sensors that help contractors measure concrete strength in real time to expedite construction timelines safely. The technology has been tested on highways in Indiana, and F.A. Wilhelm Construction is working with Purdue to test the sensors for a five-story building at the university.
WEST LAFAYETTE, Ind. — How long it takes to construct a building depends in large part on when the concrete of each floor is strong enough to take on loads.Purdue University engineers have developed sensors that could safely speed up a construction timeline by determining concrete strength directly onsite in real time.
Typically, concrete mix designs require testing before implementation in a construction project. Once those mixes have been vetted for use, the mix design cannot be altered without additional offsite testing.The technology that Purdue engineers designed would remove the need for extensive offsite testing by allowing construction contractors to verify the concrete’s maturity onsite.
“Our sensors could help make better data-driven decisions to determine the construction schedule and improve the quality of concrete construction,” said Luna Lu, Purdue’s American Concrete Pavement Association Professor of Civil Engineering.
“We’re trying to work with contractors to find out how much saving we can do for them in terms of time, cost and the number of people needed at a site, which reduces risk and improves construction safety,” Lu said. “That starts with industry collaborations to evaluate how well the sensors work.
Over the last decade, general contractors have used traditional sensors to make reliable and accurate estimates of concrete strength and maturity. But before even pouring the concrete, the method requires a monthlong process of testing the concrete mix design in the lab. A line graph is generated to note the strength of the mix design based on specific temperatures over time.
This line graph is then used to match up temperature measurements from sensors in the field. Strength values on the graph, called a “maturity curve,” help workers estimate when the concrete is strong enough to continue construction.