TITLE:
Study on Strengthening of RC Beam Column Joint Using Hybrid FRP Composites
AUTHORS:
A. Arul Gnanapragasam, G. Chitra, S. Robert Ravi
KEYWORDS:
FRP, Reinforced Concrete, Beam-Column Joints, Glass Fibre Reinforced Polymer, Basalt Fibre Reinforced Polymer
JOURNAL NAME:
Circuits and Systems,
Vol.7 No.10,
August
4,
2016
ABSTRACT: Beam-Column joints are
critical zones in reinforced concrete structures which are most vulnerable to
earthquake forces. Hence strengthening beam-column joint is vital to save the
structure and its inhabitants in case of seismic forces. Numerous retrofitting
works using fibre reinforced polymer (FRP) composites are being undertaken
worldwide. This work aims to investigate the effectiveness of strengthening
beam-column joints using natural and artificial fibres. In this study, basalt
(natural fibres) as monolithic composite (BFRP) and as hybrid composite along
with glass (artificial fibres) were used for strengthening of beam-column
joints. Totally six specimens were prepared and tested under monotonic loading.
Specimen details used were: two control specimen, two specimens for monolithic
wrapping and remaining two specimens for hybrid wrapping. The test results were
compared with control and rehabilitated specimens. The performance of the
treated joints was studied using the following parameters: initial and ultimate
cracking loads, energy absorption, deflection ductility and stiffness at ultimate.
From the test results, it was found that the hybrid combination of Basalt and
Glass FRPs were found to be more effective in the treatment of beam-column
joints. The strong column weak beam concept was achieved by failure in beam
portion which helped in preventing the catastrophic failure of the entire
structure.