Drop hammer tests of Scandinavian harness racetracks

Abstract

SummaryDrop tests were carried out on 8 Scandinavian harness racetracks in order to evaluate their shock force attenuation properties. A drop hammer model was designed to simulate the hoof strike of the horse. The analysis comprised calculations for mean hardness index, impact time and energy loss which were correlated to ground composition parameters. The range of hardness, impact time and energy loss was 246–366 s−1, 7.6–13.2 ms and 74–95%, respectively at the inner lane of the track when the fallheight 0.6 m was used. The corresponding data for an outer lane were 225–392 s−1, 8.2–13.4 ms and 78–93%. The study showed significant differences in hardness, impact time and energy absorption between racetracks and between different test areas along the same course, with the outer lane usually being the harder. The drop height 1.5 m simulated a higher hoof landing velocity but gave similar results.It is suggested that impact force influence from the ground may be detrimental to horses and significant effort should be made in track construction and management. It is postulated that tracks with adequate cushioning are likely to prevent excessive shock loading and related musculo‐skeletal disorders in racehorses.