Experimental investigation on strain rate effect of high-performance fiber reinforced cementitious composites subject to dynamic direct tensile loading

• Published in: Cement and concrete research Vol. 157; p. 106825
• Main Authors: Li, Qinghua, Jiang, Xiao, Zeng, Tian, Xu, Shilang
• Format: Journal Article
• Language: English
• Published: Elmsford Elsevier Ltd 01.07.2022; Elsevier BV
• Subjects: Cement reinforcements; Digital imaging; Dynamic direct tension; Energy absorption; Fiber composites; High performance fiber reinforced cementitious composites; Modulus of elasticity; Polyvinyl alcohol; Strain analysis; Strain hardening; Strain rate; Strain-hardening phenomenon; Stress-strain relationship; Stress-strain relationships; Tensile properties; Tensile strain; Tensile strength; Tensile tests; Strain-hardening phenomenon; Dynamic direct tension; High performance fiber reinforced cementitious composites; Stress-strain relationship
• ISSN: 0008-8846; 1873-3948
• DOI: 10.1016/j.cemconres.2022.106825

This study presents an investigation on dynamic tensile properties of high-performance fiber reinforced cementitious composites (HPFRCC). Direct tensile tests were performed on dumbbell plate specimens with the strain rate ranging from 1.98 × 10−5 s−1 to 90.01 s−1. The strain rate effect on the initial cracking strength and strain, tensile strength and strain, elastic modulus and energy absorption capacity of the HPFRCC was analyzed. The results indicated that with an increase in the strain rate, both the initial cracking and tensile strength increased, whereas the tensile strain capacity decreased, especially at rates over 1 s−1. Furthermore, several functions were employed to fit the relationship between the dynamic increment factors (DIF) and strain rate. A dynamic direct tensile model with a significant strain-hardening section was suggested to describe the stress-strain relationship. Finally, through the two-dimensional digital image correlation technology (2D-DIC) and scanning electron microscopy imaging (SEM), it was demonstrated that both HPFRCC specimens and polyvinyl alcohol (PVA) fibers showed rate-dependent failure patterns. •Static and dynamic direct tensile tests of UHTCC was conducted.•The maximum actual tensile strain rate nearly reached 100 s−1.•The mechanical parameters of UHTCC perform significant rate-sensitivity.•Strain-hardening phenomenon and energy absorption capacity were analyzed.•A dynamic direct tensile model and some microscopic scanning were investigated.