根巻き補強鋼柱脚の力学的性状に関する研究 : その1 曲げモーメントとせん断力が作用する場合

抄録

In order to clarify the mechanical characteristics of the steel column bases consolidated with RC stub, the column base models of H shape cross section were tested under alternating horizontal load. The main parameters involved in the tests were the height and covering depth of RC stub, the ratios of reinforcing bar (main bar and shear reinforcing bar), and use or unuse of stud dowel. Some observations from the test results are as follows : 1) The hysteretic behavior of the steel columns consolidated with RC stub at the column bases show the hysteretic loops of slipped shape after yield of shear reinforcing bars, and this phenomenon is more remarkable as decreasing the ratio of shear reinforcing bar. 2) The use of the top-reinforcing bar and hoop together is efficient to increase the composit effect of column bases consolidated with RC short stub. 3) The stud dowels should be used with top-reinforcing bars to secure the ductility of the column bases consolidated with RC stub. 4) The ultimate strength of the column bases can be estimated by considering the load carrying mechanism shown in Fig. 12 with the cumulative theory proposed in this paper. 5) In the modes of failure, it was recognized that the failure of the column bases consolidated with RC stub are induced by shearing action when the height of RC stub is below 3 D (D : depth of a steel column) ; to expect the composit effect of the column bases, it is important to reinforce appropriately for shearing failure.