Seismic Damage Investigation and Seismic Performance Study of Lushan Middle School Gymnasium

The seismic behavior of Lushan Middle School gymnasium, whose grid structure was heavily damaged during the Mw7.0 Lushan earthquake in 2013, is simulated by three finite-element models. In field observations, 72 buckled members were found, but no tensile failure or obvious tensile yield was found. The results of each model are analyzed by comparing the simulated damage with field observations. The results suggest that Model A shows the best analysis results, followed by Model C, and finally Model B. Causes of seismic damage not only the uneven stiffness of the structure's support columns caused by ring beams leads to redistribution of the internal forces, but the dynamic amplification effect of the lower frames also intensified the damage to the grid structure. Therefore, the authors recommend that the code should distinguish between pure grid structures and grid structures supported by RC frames and introduce design models that integrate the two structures and include a coupling effect between them. In addition, the integrated model should be used in a seismic check of grid structures with concrete supporting structures. (c) 2020 American Society of Civil Engineers.