Elastic Model of SLCD (abstract)

An Elastic Model of the Holding Power of
Spring Loaded Camming Devices
Used as Rock Climbing Anchors

Dave Custer

html markup by Susan Ruff


As a basis for specifications for the testing of spring loaded camming devices used as rock climbing anchors, two successive models of these devices are developed. The rigid body model assumes an infinitely strong, undeformable cam; it determines the cam's basic shape and the relationship between this shape and the cam's frictional holding ability. Based on the rigid body model, the second, elastic model takes deformation and material strength into account; this elastic model determines the relationship between cam shape and the shear strength of the cam. The models predict two failure modes for camming devices placed in vertical, parallel cracks: inadequate friction and shear yield failure. A measure of the limitations imposed by these failure modes would provide climbers with information necessary for intelligent anchor placement.