角形鋼管側柱柱脚の剛性と耐力に関する実験的研究 : 柱に密着するU形筋を用いた埋込み形式について

抄録

The RHS column base embedded in footings is commonly employed in rigid column-footing connections and is capable of resisting the large bending moments. However, at RHS exterior columns in building subjected to lateral loads, due to the loss in the bearing strength of concrete as a results of the failure of cover concrete, it is more awkward that the strength of this column base connection is greater than the full strength of RHS column. In this paper, to avoid such concrete failure of RHS exterior column base, an improved embedded type with U-reinforcing bars arranged on the outside of the embedded RHS column is proposed. A method of ultimate strength design is described. Experiments were conducted to verify the effectiveness of the design procedures and generally evaluate the inelastic behavior. The results are summarized as follows. 1) The lateral stiffness of RHS column is estimated by the results of the analysis including the effect of the rotation resistance of the foundation tie-beam. 2) The yield load and the collapse load of improved embedded RHS exterior column base connection are well predicted by the present method. 3) U-reinforcing bars of improved embedded RHS exterior column base connection is most effective in preventing the resistance deterioration. 4) When the reinforcing bars of the foundation tie-beam terminate at the exterior edge, a major crack at the inner side of the embedded column is restricted.