Introduction to the Simulation of Composite Concrete Beam Bending in Abaqus

This tutorial presents the five-point bending simulation of a composite concrete beam consisting of normal strength concrete (NSC) and ultra-high-performance fiber-reinforced concrete (UHPFRC) using Abaqus. The NSC cover is modeled as a three-dimensional solid part, while the UHPFRC core is also represented as a three-dimensional solid. Steel bars and strips are included as three-dimensional wire parts. UHPFRC, composed of Portland cement, pozzolans, fine aggregates, inert fillers, superplasticizer, and surface-treated steel fibers, offers superior structural performance compared to NSC. Although more expensive, its improved mechanical behavior reduces material consumption, reinforcement requirements, and maintenance costs, while extending service life.

The material behavior of concrete is defined using the Concrete Damage Plasticity (CDP) model, which combines plasticity theory with damage mechanics to provide a realistic description of concrete response. The parameters are taken from reference literature, and the model accounts for both tension and compression damage in NSC and UHPFRC. Steel reinforcements are described using an elastic–plastic model.

To perform the simulation efficiently, the dynamic explicit step is applied to reduce computation time. Proper interactions and boundary conditions are assigned to all parts, and a fine mesh is used to ensure accuracy of the results. After completing the analysis, the outputs include stress, strain, damage evolution, failure mechanisms, and force–displacement diagrams, providing a comprehensive understanding of the structural behavior of the composite beam.