Abstract:
The
path-independence property of the J-integral for a
non-homogeneous panel with a sandwiched hard layer containing a
centre crack parallel to the interfaces, and the validity of J=-
1/B ӘU/Әa
are investigated by means of elastoplastic FEM by applying the
J-integral method to the safety assessment of welded joints with
mechanical non-homogeneity. It is shown that the J-integral
remains path-independent and
J=-1/BӘU/Әa as the rate of decrease of
potential energy is still applicable in spite of
non-homogeneity. The path-independence of J in such a
non-homogeneous environment is also confirmed mathematically.
The effect of mechanical non-homogeneity upon the J-integral
values is studied. It is concluded that the yielding of the two
soft zones between which the hard layer is sandwiched tends to
make the J values increase: the smaller the relative hard layer
width h/2a, the larger are the J values at the same load level.
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