Abstract—In this study, the Champlain Towers South building collapse in Florida allegedly caused by a deck collapse was examined through the finite element analysis based on the existing hypotheses and investigation. The Adaptively Shifted Integration (ASI) – Gauss code was applied for the numerical analysis. In addition, the member strength failure algorithm of RC components was modified, and the flat-plate structure was introduced into the numerical model of the building. According to the analyses, the building did not collapse when the pool deck beams connecting to the columns of the 1st-floor interior, so-called key columns, were removed by the collapse of the pool deck. When the model was revised to include deterioration of concrete slab and corrosion of rebars, and then triggered by the removal of columns in the underground parking garage, the middle section of the buildings reached a total collapse. This supports the latest collapse theories, which cite punching shear failure at pool deck columns as the initiating event.

Keywords—collapse analysis, flat-plate structure, RC building, deterioration, corrosion, ASI–Gauss code

Cite: Daigoro Isobe, Junnan Zhu, and Janine Pardee, "A Numerical Investigation on the Collapse of the Champlain Towers South in Florida," International Journal of Structural and Civil Engineering Research, Vol. 14, No. 1, pp. 1-9, 2025.