6.2 Cross Section Classification In a continuous beam,the critical cross-sections must be capable of developing/sustaining their plastic resistance moment,under increasing load, sufficient regions have fully-yield for a mechanism of plastic hinges to be present.(plastic design) The mechanism arises as a result of redistribution of moment.To ensure that the resulting strains can be accommodated without a reduction in resistance below the plastic moment,limitations must be placed on the slenderness of the elements of the cross-section which are in compression6.2 Cross Section Classification • In a continuous beam, the critical cross-sections must be capable of developing/sustaining their plastic resistance moment, under increasing load, sufficient regions have fully-yield for a mechanism of plastic hinges to be present. (plastic design) • The mechanism arises as a result of redistribution of moment. To ensure that the resulting strains can be accommodated without a reduction in resistance below the plastic moment, limitations must be placed on the slenderness of the elements of the cross-section which are in compression