Applications of finite element method in studying mechanical behavior of concrete materials on different scales

Computer simulation is a powerful tool for understanding material behavior at a wide range of scales. This research uses finite element modeling for two investigations at two very different scales. The first study considers the microstructure of foam concrete material. The objective is providing insights for understanding the foam concrete crushing behavior, where the real foam concrete microstructure is studied. With a micro-CT scan providing the foam geometry information, tetrahedral meshes are generated for rendering the microstructure, which is further used for simulating a uniaxial compression test in Abaqus/CAE. The simulation result is qualitatively reasonable, suggesting a potential of using this approach for further exploring the foam crushing behavior. The second study focuses on investigating the thermal induced movement of the full-scale airport slabs at O’Hare International Airport. The simulation is implemented to evaluate four model configurations for estimating the opening at concrete expansion joints. After further considering the actual boundary condition, the modeling effort demonstrates acceptable accuracy of the simulation result. The good agreement between the FEM simulation and the field measurement confirms a realistic prediction overall. By studying the stress concentration in the concrete slabs in subsequent, it is found that expansion joint width plays the most critical role in alleviating the stress buildup issue as concerned by the field engineers