Laser detectors determine the degree of damage to buildings during an earthquake

The American state of California began to shake noticeably more often and harder than in previous years, and therefore it is not surprising that it was there, in the National Laboratory. Lawrence at Berkeley, developed a new technology. Scientists and engineers were faced with the following question: how to quickly assess the degree of reliability of buildings damaged by earthquakes? Is it possible to return there or is it better not to go there at all? The existing measuring systems on accelerometers turned out to be too expensive for mass adoption, something new was required.

Research has resulted in the emergence of a Discrete Diode Position Sensor (DDPS). This is a set of a laser emitter and a photosensitive matrix, which are installed on opposite floors of the structure. When it is shaken, the beam shifts and "draws" a characteristic pattern on the surface of the matrix. It remains only to study it after the earthquake, to measure the size of the patterns in order to draw a conclusion about the degree of destruction of the building structure itself.

Data can be transmitted wirelessly, rescuers with receivers do not even need to come close to dangerous ruins. First of all, after the end of the shocks, they look at which part of the matrix the beam is now shining into, how much the hit point has moved, and therefore, how much the bearing walls have shifted relative to each other. Tests on shakers have shown the high accuracy of such measurements, and now Berkeley wants to shake the real building as part of a new experiment.

"Until now, there was no reliable way to measure the displacement of elements of a large and complex structure relative to each other after an earthquake, " says Berkeley geologist David McCullen. - The new technology will not only give an answer to this question, but will also help to change, develop a strategy of action in the case of earthquakes. Rescue services will have much more relevant information about the state of structures in the disaster zone. "