有限要素法による鉄筋コンクリートの非線形解析第 2 報 : 異形鉄筋とコンクリートの付着-その 1

抄録

In the previous paper, Part 1, the discussion has been made about the applicability of the previous analytical models which represent the biaxial stress-strain relations for concrete. It is the purpose of this investigation to develop an analytical model to simulate the bond-slip behavior between the deformed bars and concrete, which is also one of the most fundamental mechanical characteristics of reinforced concrete. The model is designed as follows. The theory of orthotropic materials is applied to the internal crack zone of concrete around the deformed bar and the modulus of elasticity, E_1, nearly at right angles to the internal crack is reduced in company with the shear modulus of elasticity, G_12. Finite element calculations are compared with experimental results for the previous pull out specimens (26, 27). The results are as follows. 1) When the distribution patterns of the internal crack zone are decided by curve fitting the bond stress-slip relations to the experimental data, the analytical results of the load-slip and the load-steel strain distribution relations obtain good agreements with experimental results. 2) About concrete strain around the deformed bar, when the angle of the internal crack is 90°, the analysis in which the width of the internal crack zone is varied along the bar axis gives closer agreement with experimental data than the analysis in which the constant width is assumed. 3) When the angle of the internal crack is 45°, the deformation perpendicular to the bax axis has appeared. This deformation was also observed near the loaded end of the real specimen.