4.2.5.7. Known Limitations and Future Work

The following list contains known current limitations in the code:

  • Tight coupling is not yet supported.

  • Only nontapered two-node Euler-Bernoulli (E-B) or Timoshenko (T) element formulations are available. (In the future, tapered E-B and tapered Timoshenko element formulations will be implemented.)

  • Only straight circular members are permitted. (In the future, a generic cross section will be allowed.)

  • The number of elements per member (NDiv) is constant throughout the structure.

  • Internal matrices are not stored in sparse form, limiting the total number of possible nodes/DOFs to about 300/1800.

  • The dynamics system reduction is performed in the absence of external loading (e.g., hydrodynamic added mass).

  • Gravitational loading does not impact the global substructure stiffness.

  • Loads (gravitational, inertial, hydrodynamic) can only be applied as concentrated loads at element nodes; distributed loads (per unit length) are not yet supported.

  • The overlap of multiple members connected to a single joint is not modeled with super-elements.

  • Member-level outputs are only available for up to nine nodes of up to nine members (although the OutAll flag can generate further outputs at the member end nodes).

  • No graphics/animation capability is yet available to visualize the substructure geometry, modes, motion, and loads.