Experimental Study On Seismic Behaviors Of The Haunched Beam Transfer Structures With Varied Arrangement Of Wall Leg Of Short-leg Shearwall

In practical engineering,a growing number of high-rise buildings adopts frame-supported short-leg shearwall structure.Although the conversion of high-rise buildings in many forms,but beam transfer structure is still the main structure works in high-rise buildings, because the beam transfer structure are simple in design and construction and explicit force. Inevitably some of the short-leg shearwalls are arranged in the mid-span of the beam,because of large number of short-leg shearwalls and the shorter wall-leg, and in order to meet the architectural requirements.The stress characteristics and seismic behavior of such structure should be further researched.Through quasi-static experiments on two haunched beam transfer short-leg shearwall structure specimens with varied arrangement of wall leg under the vertical load and horizontal cyclic load,this paper observed and described the emergence and development of cracks,and recorded the cracking load, yield load and failure load,measure the structure distortion and the strain of steel bar, described in detail the failure process of specimens,made a comparative analysis on the strain variation of the steel bar.And on the basis of experimental data,this paper made a analysis on the hysteretic curves, load-resisting capacity degradation,stiffness degradation, elastic-plastic deformation and ductility, energy dissipation capacity, failure characteristics and failure mechanism.The above analysis revealed the seismic behavior of such transfer structure,thus this paper give a reasonable design suggestion and construction requirements for the haunched beam transfer frame-supported short-leg shear wall structure in practical projects.The results of the research revealer that the haunched beam transfer frame-supported short-leg shearwall structures effectively protects the beam-column joints,and such structures have good yield mechanism and failure mechanism.The rationally designed frame-supported short-leg shearwall structures have a good seismic behavior. By comparied the experimental results of the two specimens can be found that shear effect weaken the structural ductility which si caused by short-leg shearwal arranged in the mid-span of the transfer beam,but the ductility can meet the seismic code.The short-leg shearwall arranged in the mid-span of the beam is the weak part,because the short-leg shearwal has not flange,so the quantity of reinforcement of the shearwall should be increased in practical design.Transfer beam supporting the short-leg shearwall alone,so that the beam in the bottom of the opening of the shearwall is weaken,and shear failure of the beam is obvious.It's need to strengthen the shear capability of the transfer beam in the bottom of the opening of the shearwall.