Seismic Assessment of Reinforced Concrete Structures based on State-of-the-art 3D Detailed Nonlinear Finite Element Simulations

The nonlinear dynamic analysis of reinforced concrete structures is characterized by numerical instabilities, which are mainly caused by the cracking of concrete and the rapture of steel reinforcement. When dealing with this numerically unstable and computationally demanding problem, the numerical solution procedure becomes extremely cumbersome, thus leading to convergence issues. Additionally, the lack of objectivity when using 1D and 2D models does not allow the study of the nonlinear dynamic response of our structures without introducing significant simplification assumptions in-terms of material behavior and the exact discretization of the structural geometry.

In light of these well known modeling limitations, the main objective of this research work is to alleviate the above-mentioned numerical constraints by developing a state-of-the-art 3D detail modeling approach that will provide the professional Civil Engineer, and the researcher, with the ability to perform dynamic nonlinear analysis on large-scale reinforced concrete structures by accounting for Soil-Foundation-Structure Interaction phenomena. In order to achieve this objective, the numerical handling of the solution instabilities is addressed herein, while the use of the HYMOD approach is discussed as a potential solution to the overall modeling problem. Furthermore, the results from a recently developed parallel solver for the generation of embedded rebar elements within the concrete mesh will be presented. Finally, the scheduled future research work towards achieving this main modeling objective will be discussed.