Mechanics of screw joints solved as beams placed in a tangential elastic foundation

Abstract

This article deals with a new original analytical solution of deformation, force and stress states in wood screw joints up to the limit values of pulling out/breaking the screw. The screws are under tension. The wood‐to‐screw interaction is effectively simplified by introducing several physical model variants using a tangential elastic non‐linear foundation. The experimental verification of the proposed models using pull‐out tests (i.e., pulling out screws from dry spruce wood in laboratory conditions) confirms the correctness of the proposed models of the elastic linear/non‐linear foundation. The validity of the model is also analytically and experimentally verified in the biomechanical model of pulling out screws from the femur of a bovine/human cadaver, which confirms and expands the validity of newly designed screw joint models outside the timber structure area.