The correlation and determination matrices associated with the burst design of a subsea carbon-fibre-epoxy composite flow-line

This paper examines the correlation and determination matrices of the burst design in a subsea carbon-fibre-epoxy composite flow-line. A case study of a 4" flow-line is investigated. The correlation and determination matrices are calculated and compared using Pearson and Spearman correlation methods. A comprehensive suite of failure modes that comprises of Maximum Stress, Tsai-Wu, Hashin and Puck failure criteria is used to quantify the burst design. The results reveal that the failure criteria are strongly correlated to each other. The applied pressure and ply thickness are moderately correlated to the failure criteria. It is observed that due to the nature of burst loads, most material failure parameters with the exception of the Tsai-Wu constant, F12 do not exhibit correlations with the failure criteria. Second, both Pearson and Spearman correlation methods identified the same set of major design parameters. Third, it was found that the identification of the major design parameters is not affected by the sample size. This paper provides an analysis framework to aid in the identification of the major design parameters which is the initial and crucial step of a design optimisation exercise.