Infrastructure protectionSensing "skin" protects concrete structures
Scientists have developed a sensing “skin” which is made of stretchy thermoplastic elastomer mixed with titanium dioxde; patches of the skin are painted with black carbon to measure changes in the electrical charge of the skin; the skin will be rolled out in patches across structures such as bridges and dams; the formation of a crack would cause a movement in the concrete under the patch, which would change the capacitance, or stored energy, of the skin; daily check by computers would detect the change the capacitance, and issue and alert
Researchers at MIT and the University of Potsdam in Germany are working on making a “sensing skin” out of a TPE to detect cracks in concrete structures.
The prototype skin is made of stretchy thermoplastic elastomer mixed with titanium dioxde. Patches of the skin are painted with black carbon to measure changes in the electrical charge of the skin.
“The sensing skin has the remarkable advantage of being able to both sense a change in the general performance of the structure and also know the damage location at a pre-defined level of precision,” says researcher Simon Laflamme. “Such automation in the health-monitoring process could result in great cost savings and more sustainable infrastructures.”
An MIT release reports that the skin is designed to be rolled out in patches across structures such as bridges and dams. The formation of a crack would cause a movement in the concrete under the patch which would change the capacitance, or stored energy, of the skin. Once a day, a computer system attached to the sensing skin would send a current to measure the capacitance of each patch and detect any difference. Any flaws would therefore be flagged up every twenty-four hours.
The proposed sensor is superior to conventional fiber-optic versions as two-dimensional readings can be collected from one sensor, says the researchers, adding: “The safety of civil infrastructures would be greatly improved by having detailed real-time information on structural health.”
The work was funded by the German Ministry of Education and Research.
