No abstract

The Paper presents a numerical procedure for the static stress analysis of submarine pipelines during lay-barge installation. The pipeline is considered to be acted on by its submerged weight along its length and a horizontal tension at the barge end. The fourth order non-linear governing differentia1 equation of equilibrium in terms of vertical deflexions is solved using the finite difference method with the zero moment boundary condition at the sea bed end treated in a novel way. The resulting non-linear algebraic simultaneous equations are solved by the Newton Raphson method with the Jacobian matrix evaluated in an approximate manner. The validity of the computer program has been checked against an available solution. The example also shows that good agreement can be obtained with a relatively coarse mesh and that the convergence of the iterative method is quite rapid. Notationcoefficient matrix resulting from difference equations rhodulus of elasticity for the pipe depth of water at the stinger end moment of inertia of the pipe cross-section horizontal length between the two ends (stinger end and sea floor end) of the bending moment at a pipe section submerged weight of the pipe per unit length column vector representing the right-hand side of difference equations column vector representing the residuals length of the stinger tension applied at the barge end deflexion of the pipe measured from the stinger end co-ordinate axis slope of the stinger at the barge end slope of the pipe at the stinger end curvature of the pipe radius of curvature for the stinger pipeline