2007 年 10 巻 p. 391-402
3-D FEM analysis of confined concrete subjected to the axial compressive load has been carried out to investigate the confining effect and damage condition insideconcrete. In the present analysis, therefore, the influence of the transverse reinforcement ratio, the yield strength of reinforcement and concrete strength on the confining effect inside concrete has been evaluated in tarms of the confining efficiency that is related to the rate of “equivalent confining pressure”. The followings have turned out from the present analysis.(1) The confining efficiency depends on the mechanical reinforcement ratio, which is the ratio of confining pressure to concrete strength.(2) In the case of low mechanical reinforcement ratio, the confining effect extends the inner part of the concrete. Otherwise, the confining effect becomes predominant only near the comers.