Influence of Boundary Conditions on Numerical Homogenization of High Performance Concrete

Area of Science:

• Materials Science
• Civil Engineering
• Computational Mechanics

Background:

• Concrete is a ubiquitous construction material.
• High-performance concrete (HPC) offers enhanced functionality and sustainability over normal concrete.
• Understanding HPC behavior requires advanced modeling and experimental validation.

Purpose of the Study:

• To investigate the influence of boundary conditions on numerical homogenization of HPC properties.
• To compare computational modeling results with experimental data for HPC.
• To analyze the softening behavior and failure mechanisms of HPC.

Main Methods:

• Utilized the finite element method (FEM) with a two-dimensional representative volume element (RVE) for HPC microstructure.
• Employed stochastic methods for RVE generation and various constitutive models (elastic, elastic-plastic, concrete damage plasticity).
• Performed numerical simulations using Abaqus, custom Python FEM programs, and the Homtools homogenization toolbox, comparing results with experimental data.

Main Results:

• Numerical simulations accurately predicted HPC properties when accounting for damage and softening.
• Different boundary conditions (linear displacement, uniform traction, periodic) showed varying impacts on calculated HPC properties.
• The study achieved good agreement between numerical results and experimental data from the literature and the authors' own tests.

Conclusions:

• Computational modeling, particularly FEM with appropriate constitutive models and boundary conditions, is effective for predicting HPC behavior.
• The developed approach accurately captures the nonlinear response, damage, and failure of HPC.
• This research validates the use of numerical homogenization for characterizing HPC properties.