Characteristics and effects of T-stresses in central-cracked unstiffened and stiffened plates under mode I loading

Crack tip plastic zone size is affected by in-plane and out-of-plane T-stresses. The characteristics of T-stresses are obtained in flat plates and stiffened plates with three-dimensional finite element method and interaction integral method. Based on stress intensity factors and T-stresses, an improved analytical solution is proposed for crack tip plastic zone size, which is corrected with relative error analyses, then its application range is determined. The results show that the T-stresses are affected by plate thickness, crack length as well as stiffener's size, location and integrity. Both in-plane and out-of-plane T-stresses play significant roles in plastic zone size. Furthermore, structure geometry and crack size can influence the plastic zone size, but their effects are negligible under some situations, and the improved analytical solution is in excellent agreement with numerical solution then. (C) 2017 Elsevier Ltd. All rights reserved.