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9 Dynamic Responses of Reinforced UHPCC Members Under …
drop hammer impact energies. It was found that the additional transverse reinforcement could inhibit the development of shear cracks, and the effect of stress wave
propagation on impact response was more pronounced with increasing the beam
span. Jiang and Zhao (2015) put forward a method to determine the major parameters of the elasto-plastic damage cap (EPDC) model (#MAT145 in LS-DYNA),
which was suitable for low-velocity impact analysis of NSC members. It indicates
that NSC members may suffer severe localized damage (e.g., spalling of concrete
cover, diagonal shear cracks) and global damage (e.g., flexure) (Adhikary et al. 1997,
Madurapperuma and Wijeyewickrema 2013, Zhan et al. 2015).
Comparably, UHPCC is an advanced type of cementitious material with the low
water-to-binder ratio, high amount of high-range water reducer (HRWR), fine aggregates and high-strength steel fibers. Considering its excellent mechanical properties,
e.g., high compressive and tensile strength, high ductility, high fracture energy and
very low permeability, UHPCC has been becoming the most prospective construction
cement-based material of protective civil structures to resist high-speed penetration
(Dancygier et al. 2007; Farnam et al. 2010; Máca et al. 2010; Wu et al. 2015; Sovják
et al. 2015), low-velocity impact (Fujikake et al. 2006, Fan et al. 2019, Yoo et al.
2015, 2017, Wang et al. 2019b, Wei et al. 2019, Wu et al. 2019) and blast loadings
(Li et al. 2015, 2016, Mao et al. 2014, Xu et al. 2016, Wu et al. 2009).
The low-velocity impact resistance of UHPCC members is mainly concerned
in the current study. Fujikake et al. (2006) performed the 400 kg drop hammer
impact test on simply supported I cross-sectional UHPC (214.7 MPa) beams with
the longitudinal reinforcement ratio of 2.60% and five different drop heights from
0.8 m to 1.6 m. The distributed flexural cracks were detected on the mid-span bottom
of UHPC beams and an effective theoretical model of two degrees of freedom massspring-damper system was further proposed. Yoo et al. (2015, 2017) conducted the
270 kg drop hammer test on the fixed supported rectangular sectional UHPC beams
with different longitudinal reinforcement ratios (0, 0.53, 1.05 and 1.71%) and steel
fiber types (long straight, short straight and twisted). It was proved that increasing the
reinforcement ratio and adding 2% long straight steel fibers were effective to improve
the impact resistance of UHPC beams. Fan et al. (2019) experimentally examined the
drop hammer impact resistance of end-sliding supported UHPC (155 MPa) columns,
as well as the influences of axial force and three different types of UHPC jackets.
They concluded that the axial force has a significant enhanced effect on the impact
resistance of UHPC columns, and the UHPC jackets on both the impact location and
two ends were the worst configuration. Wei et al. (2019) carried out the comparable
drop hammer impact test on both the UHPC (136 MPa) and NSC (40 MPa) columns
with relatively low axial force (200 kN), square and circle cross section and releasing
height from 1.0 m to 1.75 m, and proposed a formula for assessing the residual
loading capacity of UHPC column after impact. Wu et al. (2019) and Wang et al.
(2019b) respectively conducted a series of drop-hammer tests on UHPC (141.5 MPa
and 136 MPa) filled steel tubular (UHPC-FST) and double-skin steel tubular (UHPCFDST) with simply and fixed supports, various impact energy, steel tubular thickness
and axial force, respectively. They concluded that UHPC core restricted effectively
the indentation and limited the deformation of steel tube, and the impact energy and
9 Dynamic Responses of Reinforced UHPCC Members Under …
drop hammer impact energies. It was found that the additional transverse reinforcement could inhibit the development of shear cracks, and the effect of stress wave
propagation on impact response was more pronounced with increasing the beam
span. Jiang and Zhao (2015) put forward a method to determine the major parameters of the elasto-plastic damage cap (EPDC) model (#MAT145 in LS-DYNA),
which was suitable for low-velocity impact analysis of NSC members. It indicates
that NSC members may suffer severe localized damage (e.g., spalling of concrete
cover, diagonal shear cracks) and global damage (e.g., flexure) (Adhikary et al. 1997,
Madurapperuma and Wijeyewickrema 2013, Zhan et al. 2015).
Comparably, UHPCC is an advanced type of cementitious material with the low
water-to-binder ratio, high amount of high-range water reducer (HRWR), fine aggregates and high-strength steel fibers. Considering its excellent mechanical properties,
e.g., high compressive and tensile strength, high ductility, high fracture energy and
very low permeability, UHPCC has been becoming the most prospective construction
cement-based material of protective civil structures to resist high-speed penetration
(Dancygier et al. 2007; Farnam et al. 2010; Máca et al. 2010; Wu et al. 2015; Sovják
et al. 2015), low-velocity impact (Fujikake et al. 2006, Fan et al. 2019, Yoo et al.
2015, 2017, Wang et al. 2019b, Wei et al. 2019, Wu et al. 2019) and blast loadings
(Li et al. 2015, 2016, Mao et al. 2014, Xu et al. 2016, Wu et al. 2009).
The low-velocity impact resistance of UHPCC members is mainly concerned
in the current study. Fujikake et al. (2006) performed the 400 kg drop hammer
impact test on simply supported I cross-sectional UHPC (214.7 MPa) beams with
the longitudinal reinforcement ratio of 2.60% and five different drop heights from
0.8 m to 1.6 m. The distributed flexural cracks were detected on the mid-span bottom
of UHPC beams and an effective theoretical model of two degrees of freedom massspring-damper system was further proposed. Yoo et al. (2015, 2017) conducted the
270 kg drop hammer test on the fixed supported rectangular sectional UHPC beams
with different longitudinal reinforcement ratios (0, 0.53, 1.05 and 1.71%) and steel
fiber types (long straight, short straight and twisted). It was proved that increasing the
reinforcement ratio and adding 2% long straight steel fibers were effective to improve
the impact resistance of UHPC beams. Fan et al. (2019) experimentally examined the
drop hammer impact resistance of end-sliding supported UHPC (155 MPa) columns,
as well as the influences of axial force and three different types of UHPC jackets.
They concluded that the axial force has a significant enhanced effect on the impact
resistance of UHPC columns, and the UHPC jackets on both the impact location and
two ends were the worst configuration. Wei et al. (2019) carried out the comparable
drop hammer impact test on both the UHPC (136 MPa) and NSC (40 MPa) columns
with relatively low axial force (200 kN), square and circle cross section and releasing
height from 1.0 m to 1.75 m, and proposed a formula for assessing the residual
loading capacity of UHPC column after impact. Wu et al. (2019) and Wang et al.
(2019b) respectively conducted a series of drop-hammer tests on UHPC (141.5 MPa
and 136 MPa) filled steel tubular (UHPC-FST) and double-skin steel tubular (UHPCFDST) with simply and fixed supports, various impact energy, steel tubular thickness
and axial force, respectively. They concluded that UHPC core restricted effectively
the indentation and limited the deformation of steel tube, and the impact energy and