First of all, the internal reason for the delamination or cracking is the different CTE of the packaging materials and the low surface energy of the adhesions.
The delamination crack and its effect on the fracture of pipeline steel were investigated by drop-weight tear test(DWTT)at different temperature and micrograph analysis.
Three difference buckling modes of delaminated shell were considered. The influence of boundary condition, length and depth of delamination on buckling load was analyzed.