Crack Opening Displacement Analysis of Complex Cracked Pipes based on Enhanced Reference Stress Method

개선된 참조응력법을 이용한 복합균열이 존재하는 배관의 균열개구변위 계산

An engineering estimation equation for the crack opening displacement (COD) is proposed for a complex cracked pipe, based on the reference stress approach. To define the reference stress, a simple plastic limit load analysis for the complex cracked pipe subjected to combined bending and tension is performed considering the crack closure effect in the compressive-stressed region. Comparison with ten published test data and the results from existing method shows that the present method not only reduces non-conservatism associated with the existing method, but also provides consistent and overall satisfactory results.