This paper mainly applied the large finite element calculation software ABAQUS carrying on imitating to imitate mooring line, the difference to the mooring cable of single composition and the mooring cable of the complex composition carried on an analytical calculation to get mooring cable variety of the tension with time and provide the useful reference value for the actual engineering design.
Considering the non-linear deformation effect of a mooring cable is not neglected under the condition of large deformation and large pretension, the non-linear finite element method is adopted to calculate this nonlinearity of a mooring cable.
According to the characteristics of the mooring cable,some added constraint conditions are taken into account for optimization. The optimum layout and the tension forces in the mooring cables are obtained for different sea conditions. Finally,the optimization results are found after making general comparison and analysis.
The nylon hawser connecting the tanker to the ALT was modeled as a piecewise nonlinear spring considering the nonlinear stiffness of the mooring cable. The hydrodynamic load on the tower was evaluated using Morison's equation and the wave force exerted on the tanker was calculated adopting linear wave diffraction theory,the 2-DOF coupled piecewise nonlinear differential equation was established.