Mesoscale Modeling of Steel Fiber Reinforced Concrete Using Geometric Entity Expansion and Point-Line Topology

Area of Science:

• Materials Science and Engineering
• Computational Mechanics
• Civil Engineering

Background:

• Conventional mesoscale models for fiber-reinforced concrete often neglect the volumetric effects of steel fibers, leading to physical distortions.
• Accurate simulation of steel fiber-reinforced concrete (SFRC) requires realistic modeling of fiber geometry and interactions.

Purpose of the Study:

• To develop an efficient and realistic mesoscale modeling method for SFRC that accounts for the volumetric effect of steel fibers.
• To improve the accuracy of simulating the damage mechanisms and mechanical behavior of SFRC.

Main Methods:

• A novel mesoscale modeling approach based on geometric entity expansion and point-line topology.
• Generation of polygonal aggregates using polar-coordinate perturbation and convex-hull correction.
• Steel fibers modeled as rectangular entities to represent excluded volume, using a Point-Line Method for interaction detection.
• Automated framework implemented in Python for batch generation of mesoscale models.

Main Results:

• The developed mesoscale model accurately reproduces the nonlinear mechanical response and strengthening-toughening effects of SFRC.
• Simulations showed a peak stress relative error of 0.31% and RMSE of 1.70 MPa against experimental results.
• Confirmed a ~19.7% strength gain due to steel fiber incorporation and revealed fiber bridging's role in suppressing damage localization.

Conclusions:

• The proposed mesoscale modeling approach is reliable and effective for simulating SFRC.
• The method accurately captures the mechanical behavior and damage mechanisms of SFRC at the mesoscale.
• This approach offers a cost-effective and efficient way to investigate SFRC, overcoming limitations of conventional models.