Assessment of compressive failure process of cortical bone materials using damage-based model

Area of Science:

• Biomechanics
• Materials Science
• Orthopedics

Background:

• Cortical bone failure is influenced by aging, osteoporosis, trauma, and physiological activities.
• The precise mechanisms of damage evolution and yield criteria in cortical bone remain unclear.
• Understanding these mechanisms is crucial for accurate failure analysis of bone materials.

Purpose of the Study:

• To assess the structural response and progressive failure of cortical bone.
• To utilize a brittle damaged plasticity model for simulating bone failure.
• To investigate the relationship between damage evolution and mechanical properties.

Main Methods:

• Performed compressive tests on bovine femur specimens to gather mechanical data.
• Developed a finite element (FE) model simulating elastic-to-damage behavior.
• Validated the FE model by comparing simulated and experimental load-displacement responses.

Main Results:

• FE simulations showed compressive damage initiating in the central region with maximum plastic strain.
• Damage propagation correlated with decreased structural compressive stiffness and significant strain energy dissipation.
• The compressive damage rate parameter influences failure prediction accuracy.

Conclusions:

• The brittle damaged plasticity model effectively simulates cortical bone's elastic-to-damage behavior.
• Damage initiation and propagation patterns were identified and linked to mechanical property degradation.
• Matching the compressive damage rate to experimental data improves failure prediction.