Tension, compression and buckling - element type

Altair Forum User

Hi

I'm relatively new to Hyperworks and want to carry out a size optimisation on a space-frame structure, but I'm having difficulty deciding which element type to use. I need the element to include tension, compression and buckling, but would like the initial model to simulate pin joint, so I am thinking that using beam elements gives me more than I need.

I would appreciate any advice

Cheers

Altair Forum User

Hi

I'm relatively new to Hyperworks and want to carry out a size optimisation on a space-frame structure, but I'm having difficulty deciding which element type to use. I need the element to include tension, compression and buckling, but would like the initial model to simulate pin joint, so I am thinking that using beam elements gives me more than I need.

I would appreciate any advice

Cheers

From Radioss v11.0 Help:

Beam element is used to one-dimensional structures and frames. It carries axial loads, shear forces, bending and torsion moments (contrary to the truss that supports only axial loads). Two beam elements are available in RADIOSS:

Classical Beam (/PROP/BEAM)

The default formulation is based on Timoshenko formulation; therefore, transverse shear strain is taken into account. This formulation can degenerate into the standard Euler-Bernoulli formulation where transverse shear energy is neglected.

New Beam (/PROP/INT_BEAM)

This beam element is available as of RADIOSS V51. The cross-section of the element is defined using up to 100 integration points (Fig. 2.12). The element properties of the cross-section, i.e. moments of inertia and area, are computed by RADIOSS.

Beam model is based on Timoshenko theory and takes into account transverse shear strain without warping in torsion. It can be used for deep beam cases (short beams). The use of several integration points in the section allows to get an elasto-plastic model in which von Mises criteria is written on each integration point and the section can be partially plastified contrary to the classical beam element (Type 3). The Material Law 36 is also available as Law 1 and Law 2. However, as the element has only one integration point in its length, it is not recommended to use a single beam element per line of frame structure in order to take into account the plasticity progress in length, as well as in depth.