A Comparison between Experiments and Nakanishi's Theory on the Yield Point of Mild Steel Cylinders under Internal Pressure

Abstract

According to the experiments on the yield point of mild steel cylinders under internal pressure, pressure-strain relations beyond the yield points take two different modes : - In the range of γ < 1.55, where γ is the ratio of the outer to the inner diameter of the cylinder, the strain increases under a constant pressure at the yield point Y, while in the range of γ > 1.55, the strain increases with pressure even after the yield point Y', and reaches a certain point Y at which it behaves in the similar manner to the former case (Fig. 2). F. Nakanishi has proposed a new theory on the yield point of mild steel and the experimental results have justified his theory, concerning the relation between pressure and strain as well as the stress at the yield point throughout all the range of γ.