ОЦІНКА ПОШКОДЖЕНЬ КОНСТРУКТИВНИХ ЕЛЕМЕНТІВ БУДІВЕЛЬ І СПОРУД ВІБРОАКУСТИЧНИМ МЕТОДОМ

Abstract

Purpose. Improving methods and algorithms for assessing damage and cracking of buildings and structures structural elements using the vibroacoustic method to improve the safety of their operation. Methods. Analytical methods of wave theory and statistics, experimental methods for studying the spectral density of acoustic responses. Results. For the safe operation of buildings and structures, reducing operational and environmental risks in cases of partial loss of stability, it is important to carry out timely and rapid monitoring of internal damage to their structural elements. Based on direct Fourier transforms, algorithms are proposed for transforming the spectra of selected periodic vibroacoustic signals of the structure response of a controlled object to an exciting shock effect into rectangular control pulses for digital systems. To assess the damage to structural elements of buildings and structures, it is proposed to use methods of vibroacoustic control - longitudinal profiling and vertical acoustic probing. Methodological diagnostic parameters were developed during experimental studies of concrete tubings. It has been established that the absolute deviations of the parameters characterize the change in damage along the entire length of the section under study, and the maximum values of the deviations of the parameters show the location of the most unstable (dangerous) sections. Vibroacoustic studies identified areas with increased stress, areas of hidden cracks and damage in concrete. It is proposed to determine integral indicators of damage to structural elements associated with zones of acoustic audibility of normal resonant waves. These waves are recorded by a receiver with octave filters that pass low frequencies to the structures of various materials. Originality. The method of assessing damage and cracking of structural elements of buildings and structures using the vibroacoustic method, which is distinguished by algorithms for converting the spectra of selected periodic signals of the structure response of the to an exciting impact into rectangular control pulses for digital systems, has been further developed. Practical implications. Algorithms for transforming vibroacoustic spectra make it possible to automate monitoring of damage to buildings and structures in real time, to increasing the accuracy and information content of monitoring. Based on integral indicators of damage to structural elements, it is possible to identify the risks of the objects stability loss. Keywords: buildings and structures safety, vibroacoustic methods, diagnosis of fractures.