Development of impact resistant high-strength strain-hardening cementitious composites (HS-SHCC) superior to reactive powder concrete (RPC) under flexure. (December 2021)

• Record Type: Journal Article
• Authors: Kim, Min-Jae; Choi, Hong-Joon; Shin, Wonsik; Oh, Taekgeun; Yoo, Doo-Yeol
• Is Part Of: Journal of building engineering. Volume 44(2021)
• Publication Date: 2021-12
• Subjects: High-strength strain-hardening cementitious composites -- Reactive powder concrete -- Impact resistance -- Rate sensitivity -- Energy absorption capacity; Building -- Periodicals; 690.05
• DOI: 10.1016/j.jobe.2021.102652
• Languages: English
• ISSNs: 2352-7102

Abstract

Abstract: The drop-weight impact behavior of the ductility enhanced high-strength strain-hardening cementitious composites (dHS-SHCC) is compared to that of conventional reactive powder concrete (RPC) to validate its super-impact resistance. All materials have an identical fiber volume fraction of 2%. The compressive strengths of RPC and dHS-SHCC are approximately 210 and 115 MPa, respectively. RPC has the highest ultimate tensile strength of 17.9 MPa, while the developed dHS-SHCC has the highest tensile strain capacity and energy absorption capacity up to the peak ( g -value) of 5.9% and 526.0 kJ/m 3, respectively. It also absorbs 3.2 times higher energy up to the peak under flexure (toughness) as compared to that of RPC. The RPC beams completely fail upon impact of a drop hammer with a potential energy of 490 J. However, the dHS-SHCC beams are only partially damaged along with multiple microcrack formations and rebounds. Moreover, it produces at least four times the microcracks and is more sensitive to the strain-rate than those of RPC. Consequently, it can be determined that using developed dHS-SHCC is effective in resisting impact loads as compared to RPC. Highlights: The highest tensile strength of 17.9 MPa is achieved in RPC. The highest strain capacity and g -value of 5.9% and 526.0 kJ/m 3 are obtained in UHP-SHCC. UHP-SHCC can absorb 3.2 times higher energy under flexure than that of RPC. Given a potential energy of 490 J, only the UHP-SHCC beam withstands the impact load. UHP-SHCC is more effective in resisting impact loads than RPC and HS-SHCC.