IMPROVEMENT OF THE METHOD OF CALCULATIONAL EVALUATION OF POSSIBILITY OF PROGRESSIVE DESTRUCTION OF BUILDINGS AS A RESULT OF FIRE

Abstract

With the progressive demolition of building structures, socioeconomic losses become most widespread, especially when buildings have a high degree of responsibility.

For such buildings there is a standardized requirement to carry out a calculated assessment of the possibility of progressive destruction. The article formulates the main provisions of the method of calculation for the assessment of the possibility of progressive destruction, with the failure of one or more compressed elements, and which must be removed from the general structural system of the frame of this building, consisting of steel beams, concrete and reinforced concrete columns. The basic principle of the method is the hypothesis of the formation of beams and columns of plastic hinges. Assessment of the possibility of progressive destruction is based on the energy criterion based on a comparison of the work of internal and external forces on the possible displacements of the system, which is geometrically variable in such conditions. The proposed method is productive and economical compared to existing methods that involve complex mathematical models and software complexes. When the destruction of one or more structural elements leads to the consistent collapse of the other elements, the level of socio-economic losses reaches the maximum point, since the entire building is partially or completely destroyed. In order to prevent the progressive destruction of buildings, there exists a standardized requirement to calculate such a possibility, and if its result is negative, the investigated structures should be appropriately reinforced. It is advisable to use advanced computational methods for predicting the possibility of progressive destruction, which should combine sufficient accuracy and theoretical validity with the relative simplicity of implementation and cost-effectiveness of computational operations. Therefore, the development and improvement of such methods is an urgent task.