Studies On The Seismic Performance Of CFRP Prestressed Macro-Fiber Concrete Beams

Fiber Reinforced Polymer(FRP) tendon,a new advanced composite material,is formed through pultrusion of epoxy-impregnated reinforced。FRP tendons have many advantages such as lightweight,high strength,corrosive resistance, fatigue resistance,and so on。However, since its stress-strain relationship is linear elastic without the yield point like steel bars, the mechanical performances and energy dissipation capacity of the beams reinforced with FRP tendons are unfavorable under the ultimate state。To eliminate the above mentioned shortcomings,the partially prestressed concrete,which combines the prestressing FRP tendons with ordinary steel bar, is adopted and carried experimental studies on the seismic performance of CFRP prestressed macro-fiber concrete beams。In this paper, 5 partially prestressed concrete beams were designed, the main variety parameters including stress degree, the level of stress and whether be mixed into macro-fiber. Based on experiments of FRP prestressed macro-fiber concrete beams under low reversed cyclic loading,failure pattern,hysteresis curves,ductility,rigidity degeneration,energy dissipation are studies systematically。And have a nonlinear analysis of concrete beams on the basis of ANSYS program in order to overcome the shortcomings of experiments。Studies show prestressed FRP tendons can obviously improve the carrying capacity of concrete beams;the main infactor influence of prestressed concrete beam's seismic performance is stress degree,if stress degree is about 0.65,FRP prestressed concrete beams had better seismic performance and ductility;for the same stress degree,the prestressed concrete beams'level of stress is about 0.4 have better ductility;be mixed macro-fiber into FRP prestressed concrete beams can obviously improve the ductility and seismic performance of the beams。...