ABSTRACT
Fig. 11. Tension-softening model Fig 12. Tension-softening curve predicted by the present model
We assume that the linear fracture mechanics is applicable at the microscopic level, that is, microcracks grow at K1 = K
c ;
K c
represents microscopic fracture toughness. Using the elasticity solution of the problem of Fig. 11, we obtain relation between stress and crack size after the peak,
na0 = /tan d /tan
JIA a with /d tan d (3) a
c d ' = K '
and the inelastic displacement 6 ot - 60, due to the opening of cracks, after the peak point,
na log(sec-) _
60 a -
nE'caolog(sec-a-) . (4) c log(sec)
1 , with a0
where ac is the ultimate strength, at which the microcracks start to grow, and 6t and 60 are the inelastic displacement at the current stress a and at the peak stress ac, respecitvely.
