Comparative analysis of dynamic constitutive response of hybrid fibre-reinforced concrete with different matrix strengths

• Published in: International journal of impact engineering Vol. 148; p. 103763
• Main Authors: Fu, Qiang, Bu, Mengxin, Xu, Wenrui, Chen, Lou, Li, Dan, He, Jiaqi, Kou, Hailei, Li, He
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.02.2021; Elsevier BV
• Subjects: Basalt; Basalt fibre; Compressive properties; Compressive strength; Constitutive models; Damage patterns; Dynamic damage constitutive model; Dynamic mechanical properties; Energy dissipation; Fiber reinforced concretes; Impact damage; Mechanical properties; Polypropylene; Polypropylene fibre; Reinforced concrete; Split Hopkinson pressure bar; Split Hopkinson pressure bars; Strain rate; Toughness; Dynamic damage constitutive model; Toughness; Split Hopkinson pressure bar; Basalt fibre; Polypropylene fibre; Strain rate
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2020.103763

•The addition of basalt fibre and polypropylene fibre increases the dynamic compressive behaviour of concrete.•Increasing the matrix strength and improving the strain rate exhibited a similar impact on the damage pattern of basalt fibre and polypropylene fibre.•Basalt fibre mainly contributes to the strength of concrete, and polypropylene fibre mainly contributes to the energy consumption.•A dynamic damage constitutive model was established. In this study, the dynamic compressive behaviour of concrete reinforced with hybrid basalt-polypropylene fibres (HBPRC) and different matrix strengths was investigated using a split Hopkinson pressure bar. The results indicated that the differences between the highest dynamic strength and the dynamic strength of the reference concrete for each matrix strength grade increased from 6.63 MPa, 3.77 MPa, and 4.80 MPa under the minimum strain rates to 7.16 MPa, 9.04 MPa, and 12.08 MPa under the maximum strain rates. The strain rate effect of dynamic compressive strength of HBPRC was increased by increasing the volume of hybrid basalt fibre (BF) and polypropylene fibre (PF) from 0.1% to 0.2%, but was decreased with increasing matrix strength. The toughness was increased with increasing strain rate, hybrid BF and PF volume, and matrix strength. A microscopic test indicated that an increase in the matrix strength and strain rate exhibited a similar impact on the damage patterns of BF and PF. The primary effect of BF on the dynamic mechanical properties of HBPRC was to increase the strength and that of the PF was to improve the energy dissipation. A dynamic damage constitutive model for HBPRC was established based on the continuum media and statistical damage theories, and its validity was verified. [Display omitted]