关键词: 超高性能混凝土, 准静态力学试验, 高速侵彻, 经验公式修正

Abstract: Ultra-high performance concrete (UHPC) is widely used in the field of protection due to its ultra-high strength and durability. In order to study the phenomenon and laws of projectile penetrating into ultra-high performance concrete, the quasi-static uniaxial compression experiment, split tensile experiment and high-speed penetration experiment of projectile are made on C120 ultra-high performance concrete with 1 vol% steel fibers and C160 ultra-high performance concrete with 2.5 vol% steel fibers. The modified NDRC empirical formula and the empirical formula obtained from dimensional analysis are used to calculate the penetration depths of projectile in the experiments. The results show that the ultra-high performance concrete has a higher tensile-compression ratio and superior ability to resist surface damage of the target compared with ordinary concrete. The area of crater on the surface of target is small, and the crater diameter is about 8-12 times the projectile diameter. The cracks generated in the radial direction are small and short, and the average number of cracks is 4. With the increase in the strength of ultra-high performance concrete, the diameter of crater on the surface of target and the depth of crater decrease, indicating that the addition of steel fiber improves the toughness of the target and reduces the diameter of crater on the surface of target. As compared with ordinary concrete, the penetration depth of ultra-high performance concrete is smaller, but as the strength of target increases, the penetration depth does not decrease significantly. The modified NDRC empirical formula and the empirical formula obtained from dimensional analysis can be used to predict the penetration depth of ultra-high performance concrete under high-speed penetration of projectile.

Key words: ultra-highperformanceconcrete, quasi-staticmechanicaltest, high-speedpenetration, modifiedempiricalformula