Numerical analysis of collapse load and specific strength for moderate-walled Ti6A14V-laminate composite submersible vessel under external hydrostatic pressure

摘要

The effects of geometrical imperfections on the collapse load and specific strength of moderate-walled submersible vessel made of Ti6A 14V-laminate composites and Ti6A14V alloy,respectively,have been investigated in this study.Two kinds of imperfections,which are the initial ovality along cross-section direction and the winding-induced waves along longitudinal symmetric axis,are considered.Two numerical analyses including the non-linear finite element(FE)and elastic-plastic buckling analysis are performed by the commercial software MSC Marc/Mant 2005.The obtained results indicate that initial imperfections have an obvious influence on the collapse loads of both the Ti6A14V-laminate composite submersible vessel and the Ti6A14V one.The collapse load is mainly governed by the elastic-plastic buckling critical load,which is conservative and safe for a vessel to bear the admissible failure load under the deepwater.Moreover,the Ti6A14V-laminate composite submersible vessel has a better capability to resist imperfections than the Ti6A14V one.