السلوك الزلزالي لوصلات الكمرة – العمود الخرسانية المسلحة المدعمة باستخدام الألياف المسلحة البوليمرية

RESPONSE OF SEISMECALLY DETAILED R.C. BEAM-COLUMN JOINTS STRENGTHENED WITH FRP

"Traditional types of strengthening of R.C. beam-column connections using FRP give a limited increase in strength. This research is an experimental and analytical study of the exterior beam-column connections. The main objectives of this research is focused on upgrading an ordinary exterior beam-column joint to withstand the lateral load expected in moderate earthquake zones using traditional & nontraditional methods of retrofitting (FRP) wraps. There is a need for more efficient technique of wrapping.

The experimental program included fifteen (15) medium scale reinforced concrete beam-column joints. Specimens with beam and variable stirrup spacing and different types of methods of wrapping were tested under cyclic reversed loads.

In the analytical study, the specimens were modeled using (Straus7) computer program based on finite element analysis system. The computer program was developed and modified in Sydney, Australia for the analysis of R.C. elements strengthened with FRP. On other hand, a design methodology is suggested to easily incorporate the FRP sheets in the R.C. section design.

The test results showed that, strengthening beam- column joints with traditional methods of wrapping improved the lateral strengthening, the energy index and the ductility factors of the test specimens. Using the proposed methods of wrapping the FRP as a strengthening technique increased the moment carrying capacity and ductility of the specimens by 50 percent and 30 percent, respectively compared to traditional methods.

Future study is recommended to address other types of beam-column joints and to improve the efficiency of the computer program.

Keywords: Carbon Fiber Reinforced Polymers, beam-Column connections, Confinement, Glass Fiber Reinforced Polymers, Strengthening,"