Biaxial bending of L-shape reinforced concrete column sections.

Abstract

A computer program was developed to determine the interaction curves and the isoload contours for L-Sections reinforced concrete columns. The program used the generally accepted assumption of plane sections remaining plane, but the maximum limiting concrete strain was a variable parameter. The isoload contours are relatively smooth curves with deviations only occurring in cases where the neutral axis is parallel to a major dimension of the section. This deviation from the general shape of the curve increases as the allowable concrete strain is increased and as the section is subjected to more compression. The ultimate biaxial moments increase by 3 to 6% (depending on the load level) when the maximum allowable concrete strain is increased from 0.003 to 0.004. The ultimate biaxial curvatures increase by 35 to 48% (depending on the load level) when the maximum allowable concrete strain is increased from 0.003 to 0.004.