Damage index of steel storage rack connections under cyclic loading

Ultra-high steel storage racks are becoming more common to accommodate Automatic Storage and Retrieval System (ASRS). Accurate analysis and evaluation of these storage racks are important issues especially for seismically active areas. This article presents the estimation of the damage index at beamcolumn connections in steel storage racks caused by earthquakes or other lateral forces. The damage index can be used as to assess the state of damage and serviceability of the steel racks after an earthquake. In this study, 16 beam-column connection test samples from past studies under monotonic and cyclic loading were collected. The test results were used to determine the deformation and energy dissipation at the connection to define the damage parameter in the Park-Ang damage index equation. The results showed that the deformation and energy dissipation capabilities at the connection were mainly influenced by the beam depth and the column thickness and the appropriate variable is 0.22. The result and equation developed in this study can be used to evaluate damage caused by earthquake forces for the steel storage racks.