Title:
Rapid Repair of Hollow-Core FRP-Concrete-Steel Columns
Author(s):
Mohamed ElGawady
Publication:
Web Session
Volume:
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
10/17/2021
Abstract:
This paper develops a quick repair technique in 6 hours of a new accelerated bridge construction system of hollow-core fiber reinforced polymer (FRP)-concrete-steel columns (HC-FCS). This HC-FCS column consists of a concrete wall sandwiched between an outer FRP tube and an inner steel tube. The steel tube works as a longitudinal and transverse reinforcement and the FRP tube confines the sandwiched concrete. The FRP tube protects the steel tube from corrosion because the FRP tube has no corrosion. This system offers several benefits: including reduced construction time, minimal traffic disruptions, reduced life-cycle costs, improved construction quality, and improved safety. The HC-FCS columns reduce the columns’ weight which reduces the seismic loading, the transportation costs, and the need to cranes of high capacity. Two large scale columns were tested under static cyclic lateral loading with a constant axial load. One of these columns was a conventional reinforced concrete (RC) column and the other was the HC-FCS column. The RC column failed by rebar rupture and the HC-FCS column failed by FRP rupture. The flexural strength of the HC-FCS column was 123% of that of the RC column. The HC-FCS column was repaired and retested under the same loading of the virgin column. The HC-FCS column was repaired by FRP wrapping using quake bond epoxy and grout injection. The repaired column achieved 95% of the virgin column’s flexural strength and 61% of the virgin column’s stiffness. However, the repaired column achieved 117% of the RC column’s strength and 70% of the RC column’s stiffness.