Crippling Analysis of Z-Section Composite Stringers

Z-단면 복합재 스트링거의 크리플링 해석

  • 권진회 (경상대학교 항공기계공학부)
  • Published : 1999.12.01


Crippling stress and failure behavior of Z-section graphite/epoxy composite laminated stringers are investigated by the nonlinear finite element method. Stringers are idealized using 9-node laminated shell element. The complete unloading model is introduced into the finite element method for the progressive failure analysis. A modified Riks method is used to trace the post-failure equilibrium path after local buckling. Finite element results are validated with previous experimental results. The results show that the most important parameter affecting the crippling stress of Z-section stringers is the flange width. In terms of stacking sequence. the highest cripping stress is found at the stringer with $[{\pm}45/0/90]s$ lamination.