Tests for dynamic properties of steel drive-in storage racks

The free vibration tests were performed to investigate the dynamic properties of steel drive-in storage racks with the initial displacement method. The influential factors, such as, number of bays, bracing configuration and goods pallets were taken into consideration. The test results indicated that the tested racks vibrate according to their first modal shape; top plane bracings have no influence on the natural frequencies and damping ratios of racks, but adding back spine bracings can change the dynamic properties of racks; the goods loaded in drive-in racks make their natural frequencies smaller. These tests were numerically simulated using the finite element method. The calculated results for the fundamental frequencies and free-vibration response curves of the tested racks agreed well with those of the test results. In order to estimate the fundamental frequencies of drive-in racks without back spine bracings, simplified calculation models with 2D beam elements were proposed.