Identification of Hidden Damage in Constructive Elements of Buildings and Structures to Reduce the Risks of Their Destruction

Problem statement. In emergency situations, which are activated by dynamic impacts from explosions, fires and earthquakes, it is necessary to monitor the stability of objects to assess their suitability for further operation. Purpose of the study. ensuring the safe operation of buildings and structures using methods, software and technical means for vibroacoustic monitoring of hidden damage in building structures. Methods. Analysis and generalization of data, computer modeling, experimental studies of the structures stability using the vibroacoustic method. Research results. Considered: loss of concrete stability, reinforced concrete, bricks and other elements of load-bearing structures; risk factors manifested in the gradual weakening of load-bearing building structures due to the accumulation of internal damage. Sudden loss of stability of structures occurs after the accumulation of a critical amount of damage in structural elements or the rapid growth of cracks, which are activated by the sudden unloading of extremely stressed structures as a result of any dynamic influences. By modeling the destruction process using the finite element method, it has been established that long before cracks on the surfaces of structures can be visually identified, zones of hidden damage can actively spread inside the wall structures of buildings. The main parameters for monitoring the condition of buildings and structures using visual and vibroacoustic methods have been determined. Due to the fact that the object of research is the partial destruction of buildings and structures (that is, not the root cause, but the consequences of the influence of a complex of negative main factors), two main groups of risk factors for assess the risks of stability loss have been proposed. The first group is associated with the detection of external structural damage identified by visual inspection methods. The second group is associated with the detection of hidden damage, the parameters of which are determined by the vibroacoustic method. The integral risk of stability loss is determined by comparing and selecting the maximum risk in the group. Scientific novelty. The methodology for identifying hidden damage in structural elements of buildings and structures has been further developed, which is distinguished by taking into account the parameters of vibroacoustic control of the destruction consequences and assessing the risks of the structures stability loss. Practical significance. The research results make it possible to improve the method for assessing changes in the structure of the medium as a result of the occurrence of observed and hidden systems of cracks using vibroacoustic monitoring.