Sao-shachi joint is used for the joint at column-to-beam connections with large cross-sectional areas, providing relatively high resistance and exerting a significant impact on the overall building load-bearing capacity. Therefore, the seismic performance evaluation method for column-to-beam connections with Sao-shachi is important in designing traditional wooden buildings. This study aims to develop a formula for evaluating the bending performance of such joints based on full-scale experiments. The comparison of estimated values obtained from the proposed method with experimental results generally revealed accurate predictions of failure modes and moment and rotation angle relationships.
