Dead-end Stop Terminated Tree Support Cable Systems
E. Thomas Smiley
Abstract: Supplemental support systems are used to reduce the risk of failure of codominant stems. The goal of this study was to evaluate dead-end stop terminated cables used in trees and to compare the strength of small tree cable systems. Field evaluations comparing eyebolt and Wire Stop® anchored cables found an enlargement of the hole through the branch in 39% of the Wire Stop terminations with a mean size of 6 mm. Static break tests found that the strength of cable system varied with the strength of the wood and system configuration. From a system strength perspective in oak: bent eye screw lags < welded eye screw lag = single swage stop = single swage stop with washer < double swage stop with washer = eyebolt. In pine, bent eye screw lags = welded eye screw lag = single swage stop < single swage stop with washer < double swage stop with washer = double swage stop with fender washer < eyebolt.
Keywords: Codominant Stems; Eyebolts; Ferrule; Guys; Junction Failures; Lags; Support Cable; Swage Stops; Tree Failures; Tree Support System;
V-crotch; and Wedge