BEHAVIOR OF DAMAGED EXTERIOR RC BEAM€“COLUMN JOINTS STRENGTHENED BY CFRP COMPOSITES

Authors

  • EBRAHIM ZAMANI BEYDOKHTI PH.D CANDIDATE, DEPARTMENT OF CIVIL ENGINEERING, FACULTY OF ENGINEERING, FERDOWSI UNIVERSITY OF MASHHAD, IRAN.
  • HASHEM SHARIATMADAR ASSOCIATE PROFESSOR, DEPARTMENT OF CIVIL ENGINEERING, FACULTY OF ENGINEERING, FERDOWSI UNIVERSITY OF MASHHAD, IRAN.

Keywords:

DAMAGED CONCRETE CONNECTION, CFRP LAMINATES, REHABILITATION, PERFORMANCE LEVEL, DUCTILITY

Abstract

THIS PAPER PRESENTS AN EXPERIMENTAL INVESTIGATION ON THE BEHAVIOR OF RETROFITTED BEAM-COLUMN JOINTS SUBJECTED TO CYCLIC LOADING. THE EXPERIMENTAL PROGRAM COMPRISES 8 EXTERNAL BEAMÂCOLUMN JOINT CONNECTION SUBASSEMBLAGES TESTED IN 2 PHASES; ONE WAS THE DAMAGING PHASE AND SECOND WAS THE REPAIRING PHASE. THE BEAM-COLUMN JOINTS WERE DESIGNED FOR GRAVITY LOADING. THE JOINTS HAD NO BEAM-COLUMN JOINT TRANSVERSE REINFORCEMENT AND SPECIAL STIRRUPS IN BEAM AND COLUMN CRITICAL ZONES. THESE NON-SEISMICALLY DESIGNED (NS) JOINTS WERE DAMAGED WITH DIFFERENT LEVELS AT THE FIRST PHASE OF THE EXPERIMENT. IN THE SECOND PHASE, THE DAMAGED JOINTS WERE STRENGTHENED WITH EXTERNALLY BONDED CARBON-FIBRE-REINFORCED PLASTICS (C-FRP) SHEETS. FROM THE OBSERVED RESPONSES OF THE EXAMINED SPECIMENS IT CAN BE DEDUCED THAT THE TECHNIQUE OF EXTERNALLY BONDED RETROFITTING (EBR) USING C-FRP SHEETS IS APPROPRIATE FOR THE REHABILITATION OF THE JOINTS SEISMIC CAPACITY. THIS TECHNIQUE HAD A SIGNIFICANT IMPROVEMENT OF THE LOADING CAPACITY, STIFFNESS AND THE PERFORMANCE LEVEL AND FINALLY IT LEADS TO IMPROVED TYPE OF DAMAGES COMPARED WITH THE DAMAGE MODES OF THE SPECIMENS DURING THE INITIAL LOADING. SHORTCOMINGS OF THE APPLICATION OF C-FRP SHEETS FOR PRACTICAL USE ARE ALSO POINTED OUT.

Downloads

Published

2016-02-17

Issue

Section

Articles