Modelling of composite sandwich pipe subjected to combined mechanical and thermal loading

This paper concerns the modelling of lightweight composite sandwich pipes consisting of fibre-reinforced inner and outer skins with homogeneous or graded-density core under combined mechanical and thermal loads. A finite element model capable of thermomechanical stress analysis is developed and validated against the three-dimensional elasticity solution. As an example analysis, stress states are determined for pipes comprising carbon/epoxy skins with homogeneous epoxy, homogeneous polyvinyl chloride (PVC) or graded PVC core under loads relevant to offshore piping applications. A graded core is shown to offer a compromise in terms of pipe weight and stresses in the fibre layers.