Inverse characterization of UHPC material based on Hopkinson bar test

Abstract

Coupling scientific researches with engineering applications leads to significant increase in development of innovative materials. Since time-consuming and expensive experimental tests are required for characterization of materials under dynamic loading regime, utilizing inverse characterizations of material has been increased. In this paper, an effective inverse methodology is proposed and it is utilized to determine dynamic behavior of cement-based composite material. This inverse procedure is based on the experimental test via split Hopkinson pressure bar which is one of the most widely used devices in investigation of material response to high rate loading. In the current study, Holmquist–Johnson–Cook constitutive model is used to present dynamic behavior of ultra-high performance concrete that is a new generation of concrete and has higher strength compared to traditional concrete. The reflected and transmitted waves obtained from the experiments are utilized as input in the inverse procedure. Moreover, genetic algorithm with intergeneration projection is adopted as an inverse operator to determine inversed parameters. Based on the obtained results, the recommended characterization method indicates effectiveness in the material characterization. The proposed methodology can accurately estimate the desired parameters of material under the high strain rates.

Keywords

• Inverse method
• Hopkinson bar
• Ultra-high performance concrete
• Dynamic material properties
• Material characterization