Ductile-brittle transition and minimum reinforcement ratio in lightly reinforced concrete columns

Abstract

This work reports the results of a series of tests performed on lightly reinforced concrete panels subjected to buckling load. We disclose the sensitivity of the specimens to changes in the slenderness, the load eccentricity and the reinforcement ratio. These tests were performed on scaled reinforced concrete specimens in order to reproduce the behavior of lightly reinforced concrete elements subjected to buckling. During these tests, load applied and displacements at mid-span of the specimen (additional eccentricity) were measured; the element response even after the peak load was captured. The paper proposes a simple classification of the element behavior as function of the slenderness and load eccentricity. Based on this classification, the Spanish code requirements of minimum mechanical reinforcement to avoid brittle failure in compressed elements are reviewed.