Whenever any heavy vehicle, like a truck, rumbles near a building one can always feel vibrations that go up to the roof and comes down again leading to a generation of transient tremors through intervening beams and floors. A team of researchers working at MIT recently developed a computational model that can sense such vibrations by identifying relevant major features in the noise that spells the stability of the building. This model may later be used for monitoring signs of mechanical stress or damage in a building in a long run.
Figure: Team of Researchers at MIT with Green Building in the background
Oral Buyukozturk, a professor in MIT’s environmental and civil engineering department (CEE), quotes, “The broader implication is, after an event like an earthquake, we would see immediately the changes of these features, and if and where there is damage in the system. This provides continuous monitoring and a database that would be like a health book for the building, as a function of time, much like a person’s changing blood pressure with age.”
The team examined its computational model over MIT’s Green Building – a 21-storey research building that is made of reinforced concrete completely. In year 2010, a MIT team worked in association with United States Geological Survey to fit the Green Building with 36 accelerometers that register the movements and vibrators over selected floors from the foundation to the roof of building. Buyukozturk says, “These sensors represent an embedded nervous system. The challenge is to extract vital signs from the sensors’ data and link them to health characteristics of a building, which has been a challenge in the engineering community.”
To accomplish this task, the team first started by building a high-fidelity finite element model, then installed various parameters into it along with strength and density of stairs, beams, slabs, and concrete floor of each storey. He further explains, “But the model uses a lot of assumptions about the building’s material, its geometry, the thickness of its elements, et cetera, which may not correspond exactly to the structure. So we are updating the model with actual measurements to be able to give better information about what may have happened to the building.”
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