Finite Segment Method for Biaxially Loaded RC Columns

The finite segment method is applied here to solve biaxially loaded reinforced concrete columns. The column is treated as a space structure after segmentation. The sections are divided into finite elements of steel and concrete in order to calculate its tangent stiffnesses properties at different levels of strain. The segment stiffness relationship is computed by solving the governing differential equations about the principal axes of the cross section. Direct stiffness method is utilized to construct the whole column stiffness matrix (master stiffness matrix). Nonlinearities due to material plasticity and geometrical change are handled by an iterative procedure based on the modified tangent stiffness approach. Comparisons of failure load and deflection with biaxially loaded reinforced concrete column tests show an excellent correlation between theory and test data.