Workload Benefits of Using a Synthetic Rope Strawline in Cable Yarder Rigging in Norway

oleh: Giovanna Ottaviani, Morten Nitteberg, Bruce Talbot, Karl Stampfer

Format: Article
Diterbitkan: University of Zagreb, Faculty of Forestry 2011-01-01

Deskripsi

This study examined the difference in workload brought about by exchanging a 3.5mm steel rope with a 4.0 mm synthetic fiber rope when dragging a strawline up a 300 m corridor in setting up a new cable-yarding line. Physiological workload was monitored through heart rate measurement, while the physical forces acting on the subject (rope mass and friction) were quantified using a dynamometer attached to a belt. While there was a substantial difference in force between rope types at full extent (140 N vs. 40 N), the result was less significant when seen against the total work required in moving the subjects own body mass up the slope. The direction of the resultant force vector appears to play an important role in the way that strain is experienced. It was discovered that 300 m was the maximum hauling distance for a single person using this rigging method with a steel wire strawline, whereas for the synthetic rope, the same tensile force would only be reached at 1200 m. This alone has important implications for labor saving amongst small cable logging teams.