Abstract: The Two-Parameter Method was used for the analysis of maximum bending moments in relation with the flexibility eigenvalue lambda under various cantilever arm and span lengths. The results show that the bending moment of foundation beam is not determined by the coefficient of foundation subgrade or the bending stiffness of the beam, but by the eigenvalue of flexibility. The ratio of the cantilever arm length to the span length determines the bending direction at the end of the beam and indirectly affects the overall bending moment of the beam. When the eigenvalue of flexibility is small and the ratio of cantilever length to span is in the range of 0.32～0.35, with the decrease of lambda, the change of bending moment of the foundation beam is small, in other words, the influence of lambda is small, so the stress in the frame beam is more reasonable.

Key words: anchored frame beams, two-parameter method, parametric study, structural optimization