NON-DESTRUCTIVE METHOD FOR ASSESSING THE STATE OF THE SURFACE STRUCTURE OF SHELL LIMESTONE

The article proposes a method for assessing the state of the surface structure of shell limestone. Shell limestone taken from the wall of a destroyed one-story building in Odessa was used as the test material for analyzing the surface characteristics of the structure. The structural characteristics of shell limestone vary significantly even within a single layer, so to ensure reliable adhesion of restoration materials, it is necessary to take into account the individual characteristics of the surfaces. The material was studied using modern methods of fractal analysis, which make it possible to determine the key parameters of the surface structure. For the study, photographs of the shell limestone surfaces were obtained using electronic macrophotography, which were then processed in the Guiddion software environment, designed for research in the field of scanning probe microscopy. Modern analysis algorithms were used, including image filtering, calculation of fractal dimension and construction of autocorrelation functions. This made it possible to estimate surface parameters such as roughness, texture and fractal properties. Several methods have been selected to determine the fractal dimension, which is an important task in analyzing structures such as reliefs, textures, and functional surfaces. Fractal analysis of shell limestone images was performed using several measurement algorithms – cube counting methods, triangular prisms, power spectrum, and separation (variational). The used method for assessing the state of the shell limestone surface structure allows for the selection of restoration materials with the required physical, chemical, rheological, and strength properties. The proposed approach can be used to adapt restoration compositions to porous substrates in various architectural and historical monuments.