Computer analysis of arbitrary reinforced concrete cross-section under bieccentric load

The computational aspects of the problem of ultimate strength analysis of arbitrary reinforced concrete cross-sections under normal force and biaxial bending are considered. The cross-section secant stiffness derived here insures the convergence of the solution for the equilibrium equations in any load case. The stress-strain relations of concrete and reinforcements are expressed in terms of the piece-wise continuous cubic polynomials. The coefficients of the cross-section equilibrium equations are evaluated numerically by applying the integration rules proposed by Rieckmann and Sommerfield. The present approach is demonstrated through several examples.