Experimental buckling behavior of steel pallet rack frames stabilized by single-sided spine bracing

Steel pallet rack frames stabilized by single-sided spine bracing are efficient structural systems in that they commonly carry a large number of pallets while utilizing only limited footprints. This research experimentally establishes the global buckling behavior of the steel pallet racks under vertical loads and stabilized by single-sided spine bracing. A total of eight rack frames are involved in the test program. The test setup was designed to achieve realistic loading conditions at all times. The research explicitly considered the various types of commonly used spine bracing configurations and upright frame bracing configurations in industrial practices, and generated comprehensive test data. The experimental observations suggest that the pallet rack frames stabilized by single-sided spine bracing exhibit combined translational and torsional sway motions under vertical loads, and fail by a global three-dimensional buckling of the entire frame. The investigation established that the effectiveness of down-aisle spine bracing is compromised by the rack-to-spine-bracing connections, and the strength of the global rack frame is intertwined with the stabilizing force transfer mechanism between the main rack frame and the spine bracing. The transverse shear stiffness of the upright frames in the cross-aisle direction plays a key role in determining the global torsional performance and strength of the rack frames. Recommendations for the design of pallet racks stabilized by single-sided spine bracing are proposed.