13.180. LINK180 - 3D Spar (or Truss)

Matrix or VectorShape FunctionsIntegration Points
Stiffness Matrix; and Thermal, Newton-Raphson Equation 11–61
Hydrostatic and Hydrodynamic Load VectorsEquation 11–62 [1]
Mass and Stress Stiffening MatricesEquation 11–6, Equation 11–7, and Equation 11–81

  1. For partially submerged elements, the hydrostatic/hydrodynamic load vector integration point(s) is/are centered on the wetted portion.

Load TypeDistribution
Element TemperatureLinear along length
Nodal TemperatureLinear along length

Reference: Cook et al.([118])

 

13.180.1. Assumptions and Restrictions

The theory for this element is a reduction of the theory for BEAM189 - 3D 3-Node Beam. The reductions include only 2 nodes, no bending or shear effects, no pressures, and the entire element as only one integration point.

The element is not capable of carrying bending loads. The stress is assumed to be uniform over the entire element.