The impact protection behavior of UHPC composite structure on RC columns

In order to prevent the reinforced concrete (RC) structures from being damaged under the overload impact, a new type of composite structure—ultra-high performance concrete (UHPC)–Bio-inspired honeycomb column thin-walled structure (BHTS) was designed in this paper. A scale model with a scaling factor of 1:10 was made. The experimental tests and numerical simulations of RC column and UHPC composite structure were carried out. By comparing the impact force, displacement, shear force, bending moment and energy absorption, the protective effect of the UHPC-BHTS composite structure on RC columns under lateral impact load was evaluated. Then, the failure process of RC column was analyzed, the UHPC-BHTS composite structure absorbed 76.42 % of the impact kinetic energy under the higher energy input condition, the shear failure with large damage to the RC column can be converted into bending failure with small damage. At the same time, a new damage assessment method was used to evaluate the RC column. The results show that the RC column with UHPC-BHTS composite structure can effectively protect the RC column's structural integrity under impact. The design and modeling methods in this research can provide a useful reference for anti-collision design in practical engineering.