Deformation capacity of reinforced concrete columns with smooth reinforcement

2018 ◽  
Vol 17 (5) ◽  
pp. 2509-2532
Author(s):  
Eyitayo A. Opabola ◽  
Kenneth J. Elwood ◽  
Stuart Oliver
Author(s):  
Opabola Eyitayo ◽  
Kenneth J. Elwood

Poor seismic performance of older reinforced concrete buildings in past seismic events has frequently been attributed to failure of non-ductile columns not detailed for seismic demands. The Seismic Assessment of Existing Buildings Guidelines developed in New Zealand (NZ Guideline) provides a performance-based engineering framework for assessment of existing buildings, with concrete buildings covered in section C5. This study compares the probable failure mode and deformation capacity assessed based on NZ Guideline, ASCE/SEI 41-13, and ASCE/SEI 41-17 with the results from quasi-static cyclic tests conducted on 52 rectangular and 13 circular reinforced concrete columns with reinforcement details similar to those of non-ductile columns. Results indicate that the general curvature-based method of the NZ Guideline was not able to identify the observed failure mode but generally provides a conservative estimate of deformation capacity in comparison with ASCE/SEI 41-17. Based on the results of this study, a direct rotation-based acceptance criteria is proposed for NZ Guidelines. Also, slight modifications, to reduce conservatism, have been proposed for the curvature-based method.


2019 ◽  
Vol 13 (3) ◽  
pp. 59-63
Author(s):  
E. TORE ◽  
A. YAVAS

Confinement with fiber reinforced polymers of reinforced concrete columns is promising retrofit solution for improving ductility of existing structure. In the study, plastic deformation capacityof fiber reinforced polymers confined square and rectangular reinforced concrete columns were parametrically evaluated. Recently released seismic strengthening recommendations of American Concrete Institute were considered for calculating plastic rotation of specified columns. Fiber reinforced polymers confined concrete model provided by the design guideline was utilized for calculating moment curvature relationship of fiber reinforced polymers confined reinforced concrete columns. Numerous sectional analysis was performed with combination of various parameters (concrete strength, axial load ratio and number of fiber reinforced polymers plies). Plastic rotations of columns were determined with plastic part of the curvature and plastic hinge length for evaluating the effects of parameters on plastic deformation capacity.


Sign in / Sign up

Export Citation Format

Share Document