Progressive Collapse Performance of RC Flat Plate Frame Structures

Abstract

In collapse-resistant design of structures, understanding primary structural failure-mechanisms and alternative load paths under accidental extreme loads is important. A quasi-static experimental method is used to simulate the sudden loss of a column in a single story concrete flat slab-column structure. In a series of experiments on two identical large-scale models, an interior, exterior, and corner column of the structure were replaced by mechanical jacks during the fabrication of the structure. After application of uniform loads of increasing intensity, the jack representing the lost column was unloaded. In the first model test wherein an interior column was removed, a downward concentrated load was also applied on the upper end of the interior column until the structure collapsed. Elastic behavior, yield-line mechanisms, and compressive and tensile membrane actions in the flat slab-column structure were observed during the collapse tests. The results provide valuable information on the load transfer mechanisms in a flat slab-column structure when critical columns are removed.