Tensile and Flexural Behavior of Ultra-High Performance Concrete (UHPC) under Impact Loading. (July 2021)

• Record Type: Journal Article
• Authors: Yao, Yiming; Silva, Flavio A; Butler, Marko; Mechtcherine, Viktor; Mobasher, Barzin
• Is Part Of: International journal of impact engineering. Volume 153(2021)
• Publication Date: 2021-07
• Subjects: UHPC -- flexural impact -- high-speed tensile test -- strain-rate field -- digital image correlation (DIC) -- failure localization; Impact -- Periodicals; Shock (Mechanics) -- Periodicals; Impact -- Périodiques; Choc (Mécanique) -- Périodiques; Impact; Shock (Mechanics); Periodicals; 620.1125
• DOI: 10.1016/j.ijimpeng.2021.103866
• Languages: English
• ISSNs: 0734-743X

Abstract

Highlights: Flexural impact and high-speed tension tests of UHPC specimens were conducted Absorbed energy, max load and deflection increased with increasing impact energy Tensile strength and work-to-fracture increased with increasing tensile strain rate Full field strain, cracking and localization was quantitatively studied using DIC Highly complex rate dependence of UHPC was revealed by nonuniform strain-rate field Abstract: The rate-sensitive properties of ultra-high performance concrete (UHPC) subjected to flexural and direct tensile loads were investigated. Dynamic flexural tests were performed by means of a drop hammer impact machine, whereas a servo-hydraulic system was utilized to conduct direct tension tests. The absorbed energy of the UHPC specimens under flexure increased from 0.74 to 4.49 J as the input energy varied from 6.7 to 67 J. The load-bearing capacity and maximum flexural deformation exhibited identical trends as the input energy increased. The high-speed tensile properties, including strength, ductility, and energy dissipation capacity, improved upon increasing the strain rate up to 100 s -1 . A nonuniform distribution of the deformation of UHPC specimens under high-speed tension was observed by identifying the zones of strain localization (near crack), uniform strain (far field), and shear lag (transition zone in between) using digital image correlation. The full-field data of displacement, strain, and strain rates were obtained and quantitatively evaluated. The results indicated that multiple mechanisms were involved in the rate-dependent behavior of the UHPC specimens.