5.1.19 *RELEASE

Product: ABAQUS/Standard  

Elements tested

B21    B22    B23    B31    B32    B33   

Features tested

Various types of hinged connections are tested by using the *RELEASE option to release one or more rotational degrees of freedom. Equivalent models using the *MPC option are included for comparison.

Problem description

Two beam elements are aligned with the -axis, joined at the center, and clamped at nodes 1 and 4. The *RELEASE option is used to release rotational degrees of freedom at the center, node 2. Equivalent MPC definitions are used to connect two separate nodes at the center, nodes 2 and 3.

Loading:

Step 1: The left half of the model is loaded by forces per unit length, PY = –1000 and PZ = 1000.

The right half of the model is loaded by forces per unit length, PY = 1000 and PZ = –1000.

Step 2: The loads that were applied in the first step are applied again, this time using NLGEOM for large-displacement analysis.

Results and discussion

The results are the same for the *RELEASE model and the equivalent MPC model.

Input files

xreleasepinx2.inp

Static steps, release all the rotational degrees of freedom for a beam in a plane.

xmpcpinx2.inp

Static steps, equivalent MPC type PIN for a beam in a plane.

xreleasepinx3.inp

Static steps, release all the rotational degrees of freedom for a beam in space.

xmpcpinx3.inp

Static steps, equivalent MPC type PIN for a beam in space.

xreleaserevo2.inp

Static steps, release one rotational degree of freedom for a beam in space.

xmpcrevo2.inp

Static steps, equivalent MPC type REVOLUTE plus MPC type PIN for a beam in space.

xreleaseuniv2.inp

Static steps, release two rotational degrees of freedom for a beam in space.

xmpcuniv2.inp

Static steps, equivalent MPC type UNIVERSAL plus MPC type PIN for a beam in space.

xreleaseuniv3.inp

Frequency, steady-state dynamics, modal dynamic, and response spectrum steps; release two rotational degrees of freedom for a beam in space.

xmpcuniv3.inp

Frequency, steady-state dynamics, modal dynamic, and response spectrum steps; equivalent MPC type UNIVERSAL plus MPC type PIN for a beam in space.