Dynamic Structural Analysis of a Large-Diameter Riser Consisting of Laminated Composite Material With a Hybrid Numerical Scheme

A hybrid numerical scheme is developed to analyze the structural dynamic behavior of a large-diameter riser made of a laminated composite material. The global dynamic behavior of the riser, considered as a beam element subjected to a wave and current, is solved with the finite element analysis method in the time domain. The equivalent elastic modulus of a laminated composite riser for the global dynamic analysis is calculated from the stress-strain relation of a laminate structure with a different elastic modulus. For elements in large displacement and stresses estimated from the dynamic analysis, local structural analysis is performed with the finite element analysis method to examine the structural safety of the laminates of the composite riser, which is considered as a hexahedral element. The developed hybrid numerical tool can contribute to structural safety verification of large-diameter risers composed of laminated composites.