Identification of the impact position in a reinforced concrete structure based on the analysis of the response of vibration sensors

The article presents the results of an experiment to study the vibration response of a large-scale reinforced concrete model structure to an impulse load. The load was a series of impacts along the normal to the surface of the element and was applied to all the main structural elements (columns, crossbars and floor slabs). The vibration response was recorded by a system of sensors-accelerometers distributed over the structural elements and synchronized with the accelerometer mounted on the striker. The results of measurements of acceleration vibrograms were saved as digital files. An array of vibrograms recorded by the entire complex of sensors in response to test impacts on the main structural elements made up a vibration portrait of the structure. As a result of processing this information, an array of data was obtained on the propagation time of the vibration signal from each signal source to each of the sensors of the registration system (basic array of responses). Key words: Impact localization, accelerometer, The data obtained were used to solve the problem of determining the location of an arbitrary impact on a structure. To do this, the vibration response recorded by the sensor system during an arbitrary impact was compared with the base array of responses. The comparison was made on the basis of the calculation of the pair correlation coefficients. The resulting spatial distribution of the correlation coefficients made it possible to identify the position of the shock load application. It corresponds to the structural element that has the maximum value of the correlation coefficient. The proposed algorithm was demonstrated on an example where one of the test shocks that participated in the FORMATION of the basic vibration portrait was used as an unknown load. In a numerical experiment using the proposed algorithm, it was found that the accuracy of the impact site identification corresponds to the characteristic step of the structural elements. It is shown that the accuracy correlates with the number of sensors of the registration system and their distribution throughout the structure. The developed algorithm for identifying the place of impact load application can be effectively used in the development of automated systems for deformation monitoring.