Experimental and numerical investigation of a cracked transversely graded plate subjected to in plane bending

Abstract

a b s t r a c tThe variation of stress intensity factor along the thickness in a cracked transversely graded plate subjected to in plane bending is investigated in this study. A transversely graded plate having elastic modulus varying continuously along the thickness was prepared by embedding glass beads in epoxy resin. An edge crack in this plate was subjected to in plane bending and the crack tip displacement field on the surfaces of the plate was measured using digital image correlation (DIC). Using the recently reported asymptotic displacement fields for cracked transverselty graded plates (Wadgaonkar, S.C., Parameswaran, V., 2009. Structure of near tip stress field and variation of stress intensity factor for a crack in a transversely graded material, Journal of Applied Mechanics 76 (1), 011014), the stress intensity factor (SIF) on the surfaces of the plate was calculated from the experimental data. The results of this part of the study indicated that the extent of variation of the SIF across the plate thickness is nearly the same as that of the elastic modulus. An expression to calculate the variation of the SIF through the plate thickness was developed assuming simple bending of the plate. The predicted variation of SIF was verified through finite element calculations. Further, the behavior of the SIF near the intersection of the crack front and the plate surfaces, the extent of dominance of the corner singular field and the exponent of the corner singularity were also investigated in detail. Finally, the effect of gradation strength and gradation type on the SIF was also studied.

Analysis and finite element simulations of the near-tip singular fields around a mode-3 stationary crack in plastically graded materials

“…Recent analysis of Wadgaonkar and Parameswaran (2009) around stationary cracks in transverse EGMs has obtained the structure of the near-tip stress field, which they have confirmed by their experiments (Komanna and Parameswaran, 2009). Neartip fields were obtained recently by Chalivendra (2008Chalivendra ( , 2009) for stationary cracks embedded in inhomogeneous orthotropic medium under mode-1 loading and mixed-mode loading, respectively.…”