Assessment of Existing Structures and Repairs - Offshore Structures: Design, Construction and Maintenance - page 504

Frame
geometric

FE Modeling

Analysis

Code checking

Component
failure criteria

Finish

FIGURE 7.20 Procedure for conventional analysis.

Phenomenological models

●

Shell finite element models. ●

Nonlinear Beam Column Models
Beam elements don t generally incorporate geometric nonlinearity at the

element level and multiple beam elements along a member are required to
accurately model buckling responses.
The equation of equilibrium is usually evaluated in the deformed condition,
which is the largest displacement.
Stiffness is integrated numerically from the stress distribution at points
across the section due to the combined action of axial forces and moments.
For detailed stress-strain material modeling, formulations, including strain
hardening, may be available but they may require definition in actual elemnt
performance rather than engineering format. The structure element may also
be modeled by shell elements or with a combination of shell elements, as for
joints that were damaged or have a crack and representation of members by
beam element.

'