Title: Cyclic Tests and Modeling of Stretch Length Anchor Bolt Assemblies for Dry Storage Casks
Author(s): Joel E. Parks, Chris P. Pantelides, Luis Ibarra, and David H. Sanders
Publication: Structural Journal
Appears on pages(s): 225-236
Keywords: anchor bolt; concrete anchor; cyclic tests; ductility; seismic; shear; stretch length; tension
In recent experiments, individual stretch length anchors were found to improve the tensile displacement capacity of conventional anchors under simultaneous cyclic tension and shear. Two quasistatic cyclic experiments were conducted on a 1:2.5 scale model of a dry storage cask (DSC) connected to the foundation using stretch length anchors with an eight-bar diameter (8db) stretch length. The cask was modeled using a circular steel cylinder. In the first experiment, the cask was grouted to the anchorage ring resulting in non-composite action between the cask and the “free-ring”; in the second experiment, the anchorage ring was welded to the DSC, resulting in composite action of the cask and “fixed-ring”. Both test configurations prevented horizontal sliding and toppling of the DSC. The free-ring configuration dissipated significantly more hysteretic energy compared to the fixed ring; however, this was accompanied by vertical movement of the cask. A model for individual stretch length anchors is proposed and is used to simulate the cyclic tests using finite element analysis with acceptable accuracy.