In this paper, in order to investigate the impact resistance of shear-failure type Reinforced Concrete (RC) beams, weight failing impact tests are conducted. Here, twenty-seven simply supported RC beams without stirrups are used. All RC beams used here are of 150 mm width and 250 mm depth in cross section, in which rebar and shear-span ratios are taken as variables. Impact load is singly surcharged onto the mid-span of RC beams using a 300 kg steel weight. In these experiments, impact force occurred in steel weight, reaction force, and the midspan displacement are recorded by using wide-band data recorders. After testing, crack patterns developed in the side-surface of RC beam are sketched. The results obtained from this study are as follows: 1) when the static shear-bending capacity ratio is less than 1.0, RC beams are collapsed due to severe diagonal cracks developing from the loading point to supporting points; 2) reaction force is linearly increased at incident and then is gradually decreased after reaching the maximum value; 3) after unloading, the mid-span displacement faintly vibrates accompanied by some drift; 4) the hysteresis loop between reaction force and the mid-span displacement can be assumed as a triangular; and 5) the maximum response value of reaction force is similar to that of static shear capacity.
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