Parametric study on numerical simulation of missile punching test using concrete damaged plasticity (CDP) model

摘要

To investigate the effectiveness of today's analytical methods and to improve the robustness assessment methodologies for reinforced concrete (RC) structures impacted by missiles, an international research project for benchmark tests and numerical simulations of missile impacts on RC panels was launched in the OECD/NEA/CSNI framework. Significant scatter in the predicted results in terms of the target panel displacement, panel strain, support reaction, and the missile residual velocity can be observed in the punching simulations. The benchmark punching test is chosen as a topic of this paper because the concrete and rebars are damaged the most as compared to the flexural test. In this paper, the Continuum Damage Mechanics (CDM) approach with a well posed initial boundary value problem and with the adoption of the Concrete Damaged Plasticity (CDP) model is presented. To formulate a CDM approach suitable for the simulation of complex impact problems, quantitative rules for the proper determinations of the critical material, model, and simulation control parameters are presented. Based on this CDM approach, this paper aims to establish a baseline punching simulation that can reasonably reproduce the IRIS-2012 punching test results. Furthermore, a comprehensive parametric study is performed to investigate the relative susceptibility of 14 material, model, and control parameters that are used in the simulation. Based on this parametric study, it is found that the structural and missile responses are very sensitive to most of these parameters. With these quantitative rules formulated for proper determinations of these parameters, the scatter in result predictions may be significantly reduced, and the accuracy of simulation results can be improved.