LOCAL BUCKLING PERFORMANCE EVALUATING METHOD FOR STEEL PIPE, STEEL PIPE DESIGNING METHIOD, STEEL PIPE MANUFACTURING METHOD, AND STEEL PIPE

摘要

A method for evaluating local buckling performance of a steel pipe that can evaluate whether a yield-plateau model steel pipe can be applied to a usage that requires high local buckling performance such as pipelines is provided. A specific solving means includes a first step of obtaining a stress-strain relationship of a material having a yield plateau in the stress-strain relationship; a second step of determining the comparison of a starting strain of strain-hardening in the stress-strain relationship obtained in the first step and a critical strain of the steel pipe; and a third step of evaluating that the steel pipe has a possibility of being applied to a structure that requires plastic design when the critical strain is determined to be larger than the starting strain of strain-hardening in the second step and evaluating that the steel pipe has no possibility of being applied to a structure that requires plastic design when the critical strain is determined to be not larger than the starting strain of strain-hardening in the second step.