Experimental Research And Finite Element Analysis Of Cold-Formed Thin-Wall Steel Rack

Assembled racks are structures composed of cold-formed thin-wall perforated columns and box beams. The beams are connected to the column by beam-end connectors which are welded onto the ends of the beams and often use boltless tabs inserted into the column. It is very difficulty to analyze the perforated column and the semi-rigid connections theoretically; therefore we must determine the design parameters by experiment.In the paper, 10 typical section types of non-perforated and perforated cold-formed steel rack stub column were tested under axial compressive load. We obtain the load-displacement curves of many kinds of columns and the deformation curves of the web and flange of the stub column through the experiment. Also the ultimate carrying capacity of the column and the affection factors of the perforation are determinted. And the experimental results are compared with the calculated values by the design specifications.Then 20 groups of portal frame tests were performed. The capacity of the beam and the rigidity of the semi-rigid beam-to-column connections namely the M—θ curve of the connections are tested. Also the parameters of F_b and Ff which are used for rack design are determined according to the design specifications of steel rack structures. At last the relationships among the span of beams, the section types of beams, the welded position of beams, the section types of columns and F_b, F_f are evaluated.Based on the experimental results, the commercial finite element analysis software ANSYS is employed to simulate the case of axial compressive stub column. And the results are compared with experimental data obtained by stub column tests. Also the overall working performances of the pallet racks are analyzed using ANSYS element of COMBIN14 under the condition of the semi-rigid beam-to-column connections. When the height of the lowest beam is changed, the results are calculated and compared, and the comparision shows the height of the lowest beam is not effective at all to the whole performances of the structures.