Publicerad: 2015-11-25
ISBN: 978-91-7685-900-1
ISSN: 1650-3686 (tryckt), 1650-3740 (online)
Bitumen is used as anticorrosion to protect steel armor wires of subsea cables and umbilicals. Because bitumen’s viscoelastic behavior influences the mechanical properties of cables, it is desirable to include bitumen in mechanical cable analyses. For this purpose, the author and his colleagues have in a previous scientific paper presented a newly developed laboratory instrument for identification of bitumen’s viscoelastic properties. The present paper derives an improved mathematical model for how to establish bitumen’s viscoelastic properties from the sensor measurements of the laboratory instrument. It is proved mathematically that the model of the previous paper and the model of the present paper give identical results when bitumen has shear modulus of small magnitude. The difference between the two models grows with increasing magnitude.
Arctic Engineering; Bitumen; Complex Analysis; Cross Section Analysis; Large Shear Strain; Offshore Technology; Subsea Cable; Umbilical
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