The Seismic Behaviors Of Shear Walls Reinforced By CFRP Bars And Steel Bars

The previous research emphases the importance that RC shear walls should ensure to attain ample rotations of plastic hinge region in critical-cross section and as much energy dissipation as possible through making full use of the tensile ratio and yielding of steel bars, and thus realising large ductile failure mechanism. However, due to the random of seismic oscillation it is in fact impossible to forecast the peak value, frequency spectrum, and duration of one paiticular ground motion, furthermore, taking different geological conditions and the period of building into account designers find it hard to take specific and reasonable measures to make those structures achieve the ductile failure mode under earthquake. With the living quality of residents improving, when the interior decorations, furnishing, non-structural components, electronic equipments,ect. even become more expensive than the costs of building itself, in addition to preventing the collapse of the building under rare earthquake it’s necessary and worth paying enough attention to the loss caused by the moderate and small earthquake. This paper breaks through traditional seismic design concepts, and we use CFRP bars to replace steel bars as longitudinal reinforced material, making full use of their excellent linear-elastic behavior and high tensile strength characteristics. The research showed that recoverable and self-centering behavior were achieved by those shear walls totally or partly reinforced with CFRP bars before failure, the conclusions are as follow.(1)The failure modes of the 7 specimens with different configuration types of steel and CFRP bars are the same, all of which are flexure-shear failure modes.(2)The ultimate strength capacity of the 6 specimens with CFRP reinforcement didn’t decrease significantly, and even a slight increase compared with RCSW-1,. and their strength degrations under cyclic lateral loading were very faint.(3)The stiffness degradations of the 7 specimens were consistent, and the lateral stiffness decreased rapidly in the elastic stage, and then reduced slowly with the increase of the lateral displacement, eventually tending to be a stable level.(4)The deformation capacity of RCSW-1, CFRPSW2-1 and CFRPSW2-2 was maximum with 1/65, 1/59 and 1/68 respectively. It demonstrates that all these shear walls could attain ample deformation capacity and seismic deformation reserved through reasonable configuration CFRP tendons and steel.(5)The RC shear wall specimen RCSW-1 can absorb a large amount of energy through inelastic deformation of steel bars, and its absolute energy consumption is much larger than that of the other 6 shear wall specimens, and the hysteretic energy dissipation capacity of the CFRP bars is smaller than that of steel bars.(6)The lateral residual deformations of CFRPSW-4, CFRPSW-5, CFRPSW2-1 in the same drift amplitude are only about 30% of that of RCSW-1 during elastic-plastic deformation stage, showing that CFRP bars could help control the residual deformation of shear walls effectively, which exhibites a function of self-centering.