Experimental and numerical studies on dynamic behavior of reinforced UHPC panel under medium-range explosions. (February 2021)

• Record Type: Journal Article
• Authors: Su, Q; Wu, H; Sun, HS; Fang, Q
• Is Part Of: International journal of impact engineering. Volume 148(2021)
• Publication Date: 2021-02
• Subjects: Ultra high performance concrete -- Blast -- Overpressure -- KCC model -- Numerical simulation; Impact -- Periodicals; Shock (Mechanics) -- Periodicals; Impact -- Périodiques; Choc (Mécanique) -- Périodiques; Impact; Shock (Mechanics); Periodicals; 620.1125
• DOI: 10.1016/j.ijimpeng.2020.103761
• Languages: English
• ISSNs: 0734-743X

Abstract

Highlights: A box-like blast loading apparatus is designed to provide the one-way simply-supported boundary constraints and avoid the effect of the diffracted blast waves. Blast-induced incident and reflected overpressure-time histories, and dynamic responses of panels were experimentally obtained under medium-range explosions. The effectiveness of CONWEP method in predicting the blast loadings for the present scaled distances and detonation point was proved. KCC model parameters of UHPC were comprehensively calibrated and fully validated. Abstract: This paper aims to study the blast-resistant behavior of one-way simply-supported reinforced ultra-high performance concrete (UHPC) panels through field tests and numerical simulations. Firstly, by designing a box-like blast loading apparatus, both three reinforced UHPC panels and three reinforced normal strength concrete (NSC) control panels were fabricated and tested under medium-range explosions from end-detonated cylindrical charges with different scaled distances (0.5~1.0 m/kg 1/3 ). The valuable data including the explosion-induced incident and reflected overpressure-time histories, deflection- and acceleration-time histories, as well as the post-blast damage of panels were obtained and assessed experimentally. The superiority of UHPC as a blast-resistant material was proved quantitatively by comparison with NSC. Then, the corresponding 3D finite element (FE) model was established by adopting the program LS-DYNA, both the blast loadings induced by the medium-range explosions and the constitutive model parameters of UHPC were mainly concerned. The applicability of the CONWEP method in predicting the blast overpressures was verified, but the prediction precision declines with the decrease of scaled distance since the influences of charge shape and detonation point enhanced accordingly. Moreover, based on the systematic static and dynamic mechanical tests data, the parameters of Karagozian & Case concrete (KCC) model describing the strength surface, equation of state (EOS), damage evolution, and strain rate effect of UHPC were calibrated. Finally, the present FE model, numerical algorithm and the calibrated model parameters were fully verified by comparing the numerical results with the test data, which could provide reference for the evaluation and design of UHPC structures under blast loadings.