Abstract:

Carabiners are closed hooks that can be used to secure ropes in rock climbing. Their ability to resist mechanical failure under heavy loads is critical to safety. Mechanical failure under load was modeled using finite element analysis, a powerful computational tool for solving engineering problems for complex geometries, in COMSOL Multiphysics. We modeled mechanical failure with different carabiner geometries (simplified and realistic geometries) and materials (aluminum, steel, and titanium alloys). With careful consideration of boundary conditions and uniaxial, co-linear load application, reasonable predictions of mechanical failure were obtained. Plots of the surface von Mises stresses and displacements were produced and compared to the yield strengths of the materials considered; the choice of aluminum as an optimal material among those investigated for commercial climbing carabiners was confirmed by our models, as the modeled aluminum 7075 carabiners under a 3 kN load showed a maximum surface stress of 524.9 MPa and maximum deflection of 4.45 mm, behavior appropriate for climbing conditions.