Strong Column Weak Beam Conditions

9.3.2.1 - Earthquake direction is considered for beam-column joints of highly ductile moment-resisting steel frames or reinforced concrete encased steel structural systems according to the Eq. (9.7) in accordance with the condition that columns should stronger than beams (Figure 9.2).

Eq. (9.7) shows the ratio of bending moment capacities of columns and beams on the joint, where M_pc^* is computed according to Eq. (9.8a) or Eq. (9.8b) and M_pb^* is computed according to Eq. (9.9a) or Eq. (9.9b). If the reduced beam section is used the Eq. (9.9c) or Eq. (9.9d) must be used.

In the computation of column bending moment capacities, the required axial compressive force P_ac (GKT) or P_uc (YDKT) is obtained based on 9.3.1.3, which makes these bending moment capacities the smallest in accordance with the direction of the earthquake must be considered.

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9.3.2

Related Topics

• Beam-to-Column Connection Requirements

• 9.3.4

• 9.3.1.1

• 9.3.1.1 Width-to-Thickness Ratios Report

• 9.3.1.2