A Modified Bond-Associated Non-Ordinary State-Based Peridynamic Model for Impact Problems of Quasi-Brittle Materials

Area of Science:

• Computational mechanics
• Materials science
• Solid mechanics

Background:

• Predicting the impact response and fracture of quasi-brittle materials is crucial for engineering safety.
• Existing numerical models often struggle with accuracy, stability, and capturing complex failure mechanisms like tensile-shear failure.

Purpose of the Study:

• To develop a novel bond-associated non-ordinary state-based peridynamic (BA-NOSB PD) model.
• To enhance the numerical modeling and prediction of impact response and fracture damage in quasi-brittle materials.

Main Methods:

• Implemented an improved Johnson-Holmquist (JH2) constitutive relationship within the BA-NOSB PD framework.
• Redefined volumetric strain using a bond-associated deformation gradient to improve model stability and accuracy.
• Proposed a general bond-breaking criterion, including tensile-shear failure, with a practical implementation strategy.

Main Results:

• The BA-NOSB PD model successfully eliminated numerical oscillations and unphysical deformation modes.
• Verified model accuracy and stability through benchmark examples and simulations of ceramic impact experiments.
• Demonstrated effective prediction of impact response and fracture damage in quasi-brittle materials.

Conclusions:

• The developed BA-NOSB PD model offers a robust and accurate approach for simulating impact events in quasi-brittle materials.
• The model's ability to capture diverse failure modes and its computational stability show significant promise for engineering applications.
• This work provides a valuable tool for understanding and predicting material behavior under extreme loading conditions.