Parametric Equation of Stress Intensity Factor for Tubular K-joints under In-plane Bending Load

Abstract

Stress intensity factor (SIF) is frequently used by designers to predict the integrity and residual life of a tubular joint containing a surface crack. In this study, a new numerical modelling method for cracked tubular K-joints has been presented. The proposed model has been verified from experimental results to be accurate and reliable in evaluation of the stress intensity factor for any tubular K-joint with a surface crack. Thereafter, parametric study for more than five thousand numerical models of tubular K-joints with a surface crack subjected to balanced in-plane bending load (IPB) has been carried out. A parametric equation to estimate the SIF value of any cracked tubular K-joint under IPB is then proposed based on the computed numerical results. Error analysis has been also carried out and it shows that the proposed equation can provide reliable and accurate estimation of the SIF value for cracked tubular K-joints under IPB.

Keywords

stress intensity factor (SIF)surface crack tubular K-joints balanced in-plane bending loads (IPB)

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