5.1.17 *PRE-TENSION SECTION

Product: ABAQUS/Standard  

Elements tested

B21    B31   

C3D6    C3D8    C3D8IH    C3D8R    C3D10    C3D10M    C3D20    C3D27H   

CAX4    CAX4RH    CAX8R    CAX4T   

CPE3    CPE3H    CPE4    CPE4R    CPE8    CPE8RT   

CPS4R    CPS6M    CPS8   

T2D2    T3D2    T3D3   

Feature tested

Applying a prescribed assembly load on a variety of structures by means of the *PRE-TENSION SECTION option is tested.

Problem description

This set of tests verifies that the proper prescribed assembly load is applied to a structure using the *PRE-TENSION SECTION option. Loading is done by enforcing either a concentrated force (pre-tension load) or a displacement (tightening) at the pre-tension node (see Prescribed assembly loads, Section 19.5.1 of the ABAQUS Analysis User's Manual, for a description of this option). The structure is preloaded in the first step. In most cases it is further loaded in the second step, ensuring that the tightening is maintained.

The majority of the models are two-element meshes with boundary conditions that allow for uniform stretching of the cross-section. Thus, results verification is straightforward. Some input files have several two-element meshes with different element types set up in parallel.

The *SECTION FILE output request (see Output to the data and results files, Section 4.1.2 of the ABAQUS Analysis User's Manual) is used in the first input file to output the total force in the defined pre-tension sections. The total force results in the direction perpendicular to the sections match the reaction forces at the reference nodes associated with the pre-tension sections exactly.

The analyses include a submodel run (with the pre-tension section fully enclosed by the submodel boundary) and a substructure run (where the substructure's retained degrees of freedom belong to the pre-tension section).

Results and discussion

Analysis results indicate that the prescribed force or displacement is always established across the pre-tension section. Uniform sections yield a uniform axial stress given the analysis boundary conditions. Results after subsequent loading in the second step also indicate that the prescribed tightening of the section is maintained properly.

A full example that makes use of this feature is included in Axisymmetric analysis of bolted pipe flange connections, Section 1.1.1 of the ABAQUS Example Problems Manual.

Input files

xptssib2a.inp

Tests in parallel, multiple element types; *SECTION FILE tests.

xptspit3.inp

Linear static perturbation.

xptsse23.inp

Tests in parallel, multiple element types.

xptssh2a3.inp

Hyperelastic material.

xptsri2.inp

Static analysis, Riks method.

xptsdib.inp

Dynamic analysis.

xptsdea.inp

Dynamic analysis with orthotropic material.

xptsdh2.inp

Direct-integration and subspace-based steady-state dynamics with hyperelastic material.

xptsti2a.inp

Coupled temperature-displacement.

xptsfit.inp

Natural frequency extraction with steady-state dynamics.

xptssi3.inp

C3D10 mixed with C3D20 elements; automatic midface node generation.

xptssh3.inp

*TRANSFORM used on section nodes.

xptssi23.inp

User-defined section normal; degenerate elements.

xptssi2z.inp

Static analysis with substructures.

xptssi2.inp

Submodeling, global analysis.

xptssi2s.inp

Submodeling, local analysis.