Seismic retrofit method with the knee members for preventing thejoint fracture of the angle brace was proposed. A series of loading test and analysis have been carried out to investigate validity of this method. The joint fracture prevention was confirmed by installing the knee members. The load sharing ratio could be expressed by the proposed model. Consideration is needed by the load sharing ratiochanged by holding angle of the knee members, the installed height of the knee members, stiffiness of the knee members and holding angle of a brace to make this method reach the reinforcement target
