Effect Of Material Nonlinearity On Submarine Pipeline During Laying
Dr. Hakim Saeed Muhammed, Dr. Karim Radhi Obead, Anwar Sabah Abd Alameer
Index Terms: Material, Nonlinearity, Bending moments, Deflections, Stresses
Abstract: The main causes of nonlinearity are the large deformations attained to a structural member which is related to the geometrical shape of that member. This is called geometric nonlinearity whilst the other nonlinearity is due to material behavior under load application. In this study a submarine pipelines are taken into considerately. The two mentioned nonlinearities are facing workers in structural pipeline analysis. The present paper focuses on the effect of material nonlinearity. It was tested though the use of OFFPIPE famous software. The effect of material nonlinearity was studied through the obtained bending moments, deflections and stresses when the pipe exposed to depth variation, diameter variation, tension variation and thickness variation. It was noted that if material nonlinearity is taken into consideration the governed maximum bending moments were less by about two times compared to linear approach.
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