Experimental Study on Dynamic Splitting Tensile Failure Mode of Carbon Nanofibers Reinforced Concrete

¹ College of Aeronautics Engineering, Air Force Engineering University, Xi’an, Shaanxi, 710038, China
² College of Mechanics and Civil Engineering, Northwestern Polytechnical University, Xi’an, Shaanxi, 710072, China

Abstract

Carbon nanofibers (CNFs) were used as admixtures to modify traditional concrete, and carbon nanofibers reinforced concrete (CNFC) with fiber volume fraction of 0%, 0.1%, 0.2%, 0.3% and 0.5% were prepared. The dynamic splitting tensile tests of concrete with different fiber volume contents under five loading rates were carried out by using the Φ100 mm split Hopkinson pressure bar (SHPB) test device. Based on the observation and analysis of the failure modes of the specimens, combined with the energy change rate of incident wave, the failure characteristics of CNFC under dynamic splitting tensile load are expounded. The results show that: the addition of CNFs has a certain inhibition effect on the dynamic splitting tensile failure of concrete; the failure modes of the specimens are the central failure along the loading direction; with the increase of the energy change rate of incident wave, the damage degree of the specimen is gradually aggravated.