Skyline analysis with log drag

Abstract

This paper describes a mathematical formulation and a computer program in basic language for analyzing the load carrying capacity of skyline systems using the effects of log drag. The actual log and ground geometry are used in the analysis of the payload capacities for standing, live and running skylines. The paper uses an example problem to show the effects of the various parameters used in computing payload capacity using the effects of log drag (choker length, log length, log to ground clearance, point of choker attachment, center of gravity of the log, coefficient of friction, and type of carriage). The method described in this paper was compared with an existing method which calculates skyline payloads for a fully suspended load. It was found that when logs have one end suspension, there can be considerable difference in the payloads calculated by the two methods.