A study on seismic capacity of overhead transportation systems in a high-tech fab

This study investigates the seismic capacity of the OHS (Overhead System), a transport equipment system in the cleanroom of high-tech factories. By using full-scale static cyclic loading tests, the fracture strength and failure modes at different stages of lateral displacement could be observed. The retrofit program proposed for the OHS not only reduced the problem of the loosened connection points, but also efficiently increased system strength to the designed bracing strength. Structural analysis software SAP2000 was used to build a simulated numerical model, and nonlinear static pushover analysis was performed. We then compared the analysis results to those of the full-scale experiment to understand the internal force distribution. Finally, the computer model analysis quantified system retrofit proposals - effectively enhancing system strength with the least number of members added.