RC Frame Behavior at a Column Collapse Scenario Considering Crack Opening Effects.

This study examines the influence of the reinforced-concrete frame topology and crack opening effects on the structural behavior under a column removal scenario. For this purpose, a variant of discretization of the finite element model has been proposed, which takes into account additional rotations during the formation of discrete cracks. As a criterion of the bearing capacity of structures, the equilibrium point at the force-displacement curve was adopted. Verification of the proposed method has been performed using experimental data for a U-shaped frame. The paper provides a comparative analysis of the calculation results for 3-story, 5-story and 9-story reinforced-concrete frames using structural elements and the proposed method. It is found that accounting for the discrete nature of cracks had practically no effect on the magnitudes of axial forces in the elements. However, for bending moments, the proposed method showed a decrease compared to the traditional approach. The increase of axial tensile forces in the support sections of the beam above the zone of local failure has been detected for reinforced-concrete frames with 3 - 5 stories, which can lead to an increase in the influence of buckling for the columns to which such a beam is adjacent. [ABSTRACT FROM AUTHOR]