Abstract
In this study, we investigated the loosening behavior of screw rotation under transverse cyclic loads using 3D-FEM analyses. Tightening and loosening tests were carried out for validation of the FEM analyses. It was confirmed that the loosening of screw rotation occurs due to accumulation and release of elastic torsional force during cyclic loading. FEM analyses provided that the improved formula considering elastic torsion would be helpful to evaluate the loosening of screw rotation.
