Author(s)

N Kishi, H Mikami & T Ando

Abstract

In this study, to investigate the impact-resistant behavior of shear-failure-type reinforced concrete (RC) beams, falling-weight impact tests were conducted by means of a single loading method. Nineteen simply supported rectangular RC beams were used for these experiments. All RC beams were of 200 mm wide, 400 mm deep, and 2,400 mm long in dimensions, in which shear rebar ratio and impact velocity were taken as variables. An impact load was applied on to the mid-span of each RC beam by dropping a steel-weight (hereinafter, striker) with a 400 kg mass. In these experiments, the impact force excited in the striker, the reaction force and the mid-span displacement were measured and recorded by wide-band analog data recorders. The results obtained from this study are as follows: 1) when the RC beam reaches the ultimate state with shear-failure mode, reaction force vs. mid-span displacement curve forms an isosceles triangle, irrespective of magnitude of shear rebar ratio; 2) at the time, maximum reaction force reaches an absolute value; 3) using the relationship between absolute maximum dynamic reaction force and static shear capacity, an impact-resistant design for shear-failure-type RC beams can be rationally performed using the static shear capacity.

Keywords