Finite Element Analysis Example
Composite Bearing Simulation Using a Rigid Pin
This finite element analysis demonstrates how a composite coupon responds when a rigid pin applies bearing load to the surface of a hole. The animation presents the resulting longitudinal normal stress, S11, as the load is transferred from the pin into the surrounding composite material.
What to watch: As the rigid pin loads the hole, the S11 stress field develops around the pin-loaded region and spreads into the surrounding composite coupon.
Finite element analysis animation showing the development of S11 longitudinal normal stress in a composite coupon loaded through a rigid pin. No preload or initial stress is applied to the specimen.
What Does This Bearing Simulation Show?
In this model, the pin is treated as a rigid body while the composite coupon is allowed to deform. As the pin moves against the hole, the surrounding laminate carries the transferred load and develops a non-uniform stress field.
The animation displays S11 longitudinal normal stress. It shows how stress in the model's local material 1-direction develops and spreads through the coupon during loading.
No preload or initial stress is applied to the specimen. The stress shown in the animation is produced by the bearing load transferred through the rigid pin during the analysis.
How to Interpret the Animation
Pin-to-Hole Load Transfer
The rigid pin applies load to a local region of the hole. The surrounding composite material then redistributes this load through the wider coupon.
Localised Stress Development
S11 stress is highest in selected regions around the pin-loaded hole because the load does not enter the coupon uniformly across its full width.
Stress Redistribution
Moving away from the hole, the stress field spreads through the coupon. This helps engineers understand how the joint transfers load into the connected structure.
What Is S11 Stress?
Normal Stress in the Local Material 1-Direction
S11 is the normal stress acting in the model's local 1-direction. For a composite laminate, this direction is defined by the assigned material orientation and may correspond to the principal longitudinal reinforcement direction.
Positive and negative S11 values represent opposite normal-stress directions. Depending on the local coordinate definition, these may be interpreted as tensile and compressive longitudinal stress.
The contour should therefore be interpreted together with the laminate orientation, ply direction and numerical stress legend shown in the FEA results.
Why Analyse S11 Around a Pin-Loaded Hole?
Directional stress results help engineers understand how a composite laminate carries load around a mechanically fastened connection.
Identify Critical Stress Regions
Locate areas around the hole where longitudinal normal stress becomes concentrated during bearing loading.
Compare Laminate Configurations
Assess how changes in ply orientation, laminate thickness or reinforcement distribution affect the S11 stress field.
Review Joint Geometry
Investigate the influence of hole diameter, coupon width, edge distance and surrounding geometry.
Support Physical Testing
Use the predicted stress distribution to plan bearing tests, select inspection areas and interpret observed specimen damage.
Evaluate Load Paths
Understand how load entering through a rigid pin spreads into the surrounding composite structure.
Reduce Development Risk
Identify potentially unfavourable stress distributions before committing to production tooling or full-scale prototypes.
This animation presents S11 stress only. It does not, by itself, establish the ultimate bearing strength or predict the complete failure behaviour of the composite joint. A full engineering assessment may also consider other stress and strain components, contact behaviour, laminate orientation, composite failure criteria, progressive damage, boundary conditions and physical test results. The displayed deformation may also be scaled for visualisation.
Need FEA Support for a Composite Joint or Pin-Loaded Component?
Composyne provides finite element analysis and composite engineering support for mechanically fastened joints, structural laminates, FRP components and other load-bearing composite products.
Discuss Your Project