Wire Cable Failures in Climbing Anchor Chocks


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Anchor chocks are used in the sport of rock climbing for providing secure attachment to a rock face. They are used at regular intervals and must be light weight (since many are carried) and also sufficiently strong to withstand an impact force should a climber fall from a height. In chock design, steel wire cable is widely used for connecting the nut component, which is wedged into a rock crevice, to the free end which attaches, via a karabiner link, to the safety rope. However, the wire cable is vulnerable to failure as it can fray with use at exposed ends - especially when folded into a loop using tight bends. Also, the ferrule end connections are considered a potential design weakness. In a research programme tests have been carried out on new and also some well used anchor chocks and has revealed very different, and some unpredicted, failure modes – depending on the state of the wire rope and whether the applied load at failure was static or impact. This paper presents the results of test failures for a range of chocks and discusses the benefits of using single lengths of wire cable with suitably swaged end ferrules.



Key Engineering Materials (Volumes 348-349)

Edited by:

J. Alfaiate, M.H. Aliabadi, M. Guagliano and L. Susmel




J. Vogwell and J. M. Minguez, "Wire Cable Failures in Climbing Anchor Chocks", Key Engineering Materials, Vols. 348-349, pp. 165-168, 2007

Online since:

September 2007




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DOI: https://doi.org/10.1007/978-0-387-46050-5_8