К ПОСТРОЕНИЮ ДЕФОРМАЦИОННЫХ КРИТЕРИЕВ ОСОБОГО ПРЕДЕЛЬНОГО СОСТОЯНИЯ ВНЕЦЕНТРЕННО-СЖАТЫХ ЭЛЕМЕНТОВ ЖЕЛЕЗОБЕТОННЫХ КАРКАСОВ ЗДАНИЙ И СООРУЖЕНИЙ

Abstract

At emergency situations caused by the sudden removal of one of the load-bearing elements from the building frame, a stress-strain state is more disadvantageous in comparison with their stress-strain state at the stage of normal operation. In cases where the eccentrically compressed elements have an "elegant" section, or have acquired environmental (corrosion) or mechanical (chips) damages during operation, as a possible scenario for the exhaustion of their bearing capacity is buckling. The paper proposes an approach to the construction of deformation criteria for assessing the special limiting state of eccentrically compressed bar elements of reinforced concrete frames. The approach is based on the use of a combination of nonlinear deformation analysis and nonlinear form stability analysis. It is shown that the limiting values of deformations for the considered reinforced concrete element can be determined by the criteria of strength or stability, depending on the ratio of the sizes and structure of sections of the bar elements, as well as the ratio of the forces acting in them.