Title: Dynamic Response of Reinforced Concrete Beams Following Instantaneous Removal of a Bearing Column

Author(s): Ying Tian and Youpo Su

Publication: IJCSM

Volume: 5

Issue: 1

Appears on pages(s): 19-28

Keywords: compressive arch action; dynamic impact factor; dynamic response; progressive collapse; reinforced concrete beam

DOI:

Date: 6/30/2011

Abstract:
This paper documents an experimental study of dynamic response of reinforced concrete beams following instantaneous removal of a bearing column. Four half-scale specimens representing two-span beam bridging across the lost column were tested. The test boundary conditions simulated rotational and longitudinal restraints imposed on a frame beam by the neighboring structural components. The gravity loads were simulated by attaching mass blocks on the beams at three locations. Dynamic loading effects due to sudden removal of a column were simulated by quickly releasing the supporting force at the middle of the specimens. The experimental study investigated the load-carrying capacity of beams restrained longitudinally at the boundaries and dynamic impact on forces. The tests confirmed the extra flexural strength provided by compressive arch action under dynamic loading. The tests also indicated that the dynamic amplification effects on forces were much lower than that assumed in the current design guideline for progressive collapse.