This paper presents the simplified approximate equation for the ultimate moment of reinforced concrete exterior beam-column joint. The proposed equation is constructed of the dominant terms of the theoretical equation. The convergent calculation is omitted, and the neutral axis ratio and the stress of the outside column rebar are given by empirical equations. The proposed approximate equation is applicable not only when both the beam and column rebar yielding but also when the stress of the column rebar is given by the critical reinforcement.
