Abstract
Ultimate strength formula is derived herein, for K-type braced frame subjected to alternately repeated horizontal load. The mechanism of the progress of beam yielding is also precisely investigated. The review of the past experimental studies on the hysteretic behavior of K-type braced frame, provides following conclusions, showing good agreement with the proposed formula. 1 The strength deteriorates under repeated loading with constant displacement amplitude. This property is much influenced by the brace slenderness and the beam strength. 2 The variation of the strength under repeated load with increasing displacement amplitude much depends on the amplitude increment. 3 The strength of the K-type braced frame having the brace designed to buckle out of the plane, may seriously decrease under repeated loading.
