Presenter Information

Scott F. Arnold, Fyfe CompanyFollow

Location

London

Event Website

http://www.csce2016.ca/

Description

Advanced composite materials composed of carbon and glass fiber reinforced polymers, have been used to retrofit reinforced concrete columns for over two-decades. The original testing of these systems started in the late 1980’s and continues to the present day. The first tests, performed at the University of California at San Diego under the guidance of Professor Nigel Priestley, were focused on the use of unidirectional composites that were oriented in the transverse direction. The goal of many of the these tests was to essentially supplement the existing transverse reinforcement in order to change what would have been a premature shear failure into a flexural, ductile mode of failure. Effectively, these tests were forcing the columns to fail in the upper and/or lower hinge regions, while increasing the displacement ductility and preventing premature shear or lap splice failure (Paulay and Priestley 1992; Priestley et al. 1996). Similar testing was then performed at various universities (e.g. University of California at Irvine, University of Nevada, Reno, University of Southern California, University of Canterbury Christchurch, New Zealand and the University of Toronto) in order to validate both the glass and the carbon fiber reinforced polymers for this type of application. The structural testing then turned to the validation of these advanced composites to provide the same performance on noncircular columns, including rectangular, diamond, flare and even square shapes with re-entrant corners. Some of these column cross sections require the use of advanced composite anchors in order to achieve the same performance goals. All of these tests concluded that once the longitudinal steel had buckled or fractured, the column repair was no longer feasible. This is due to the fact that inelastic strain capacity of the buckled bars is severely diminished.


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Jun 1st, 12:00 AM Jun 4th, 12:00 AM

STR-947: COLUMN RETROFIT BY PLASTIC HINGE RELOCATION USING ADVANCED COMPOSITE MATERIALS

London

Advanced composite materials composed of carbon and glass fiber reinforced polymers, have been used to retrofit reinforced concrete columns for over two-decades. The original testing of these systems started in the late 1980’s and continues to the present day. The first tests, performed at the University of California at San Diego under the guidance of Professor Nigel Priestley, were focused on the use of unidirectional composites that were oriented in the transverse direction. The goal of many of the these tests was to essentially supplement the existing transverse reinforcement in order to change what would have been a premature shear failure into a flexural, ductile mode of failure. Effectively, these tests were forcing the columns to fail in the upper and/or lower hinge regions, while increasing the displacement ductility and preventing premature shear or lap splice failure (Paulay and Priestley 1992; Priestley et al. 1996). Similar testing was then performed at various universities (e.g. University of California at Irvine, University of Nevada, Reno, University of Southern California, University of Canterbury Christchurch, New Zealand and the University of Toronto) in order to validate both the glass and the carbon fiber reinforced polymers for this type of application. The structural testing then turned to the validation of these advanced composites to provide the same performance on noncircular columns, including rectangular, diamond, flare and even square shapes with re-entrant corners. Some of these column cross sections require the use of advanced composite anchors in order to achieve the same performance goals. All of these tests concluded that once the longitudinal steel had buckled or fractured, the column repair was no longer feasible. This is due to the fact that inelastic strain capacity of the buckled bars is severely diminished.

http://ir.lib.uwo.ca/csce2016/London/Structural/89