Title:
Damage and Failure of RC Flat Slabs Subjected to Impact Loading
Author(s):
David Z. Yankelevsky, Yuri S. Karinski, and Vladimir R. Feldgun
Publication:
Symposium Paper
Volume:
365
Issue:
Appears on pages(s):
79-92
Keywords:
column-slab connection, dynamic response, flat slabs, impact, progressive collapse, punching shear, reinforced concrete, shear reinforcement.
DOI:
10.14359/51746685
Date:
3/1/2025
Abstract:
Punching shear failure of RC flat slab connections cause loss of slab’s supports. The detached slab is falling and impacting the slab below. That problem requires thorough investigation and appropriate design guidelines. This paper presents research results on various aspects of this impact scenario. The analysis is based on an advanced numerical model that has been formulated, and the impact analyses follow the damage evolution in the concrete and reinforcement until complete connections failure of the impacted slab is developed, and a progressive collapse scenario starts. The effects of slab geometry and material properties were examined, and the contribution of special shear reinforcement and integrity rebars were investigated. The potential contribution of added drop panels to enhance slab resistance were examined. The slabs impact effect on the supporting columns has been investigated as well. The suitability of current static loading design-criteria to provide safe design against dynamic/impact punching shear is assessed. It shows that the current static-loading based design standards cannot ensure resilience of flat slab connections to impact loading and therefore cannot prevent a progressive collapse scenario. Analyses results are compared with inspected failure details of a collapsed RC flat slabs parking garage building, and excellent agreement is obtained.