Simulating IEC DLC 1.6

Dear all,

I’m running extreme load analysis with FAST for jacket substructures. While looking further into the selection of simulation parameters I came across this clause in IEC 61400-3: “Calculation of DLC 1.6b may be omitted if in the treatment of DLC 1.6a, the non-linear wave kinematics are properly represented in the dynamic simulations of the severe stochastic sea state”

Are the here mentioned non-linear wave kinematics sufficiently covered by enabling the second-order waves?
How do you deal with load case 1.6a and 1.6b?

Many thanks in advance and kind regards,

Dear Manuela,

The answer probably depends on the water depth, wave length, and wave height (wave steepness). Often wave kinematics are simulated in load case 1.6a with a constrained wave simulation (which is not functionality available in the current version of FAST/HydroDyn). See Appendices C and D for more information.

Best regards,