| High axial compression ratio shear wall always exists in high-rise structures and bottom stories of structures. Ductility of high axial compression ratio shear wall is poor and reflects fragile feature at failure program sometimes. So on the condition of high axial compression ratio, it is urgent in engineering field to develop a new kind of shear wall which has better seismic behavior. In this paper, medium-high shear wall with concealed truss has been brought forward. This new composite concealed shear wall includes two kinds of composition. One is composition of two bearing systems—truss and shear wall and the other is composition of two materials—steel and concrete. So it is a double composite shear wall. In this paper,a new kind of shear wall is presented and experimental study and theoretic analysis on the seismic behavior have been done.The main contents are listed as follows:1. The experimental study on the seismic behavior of five medium-high shear walls with 1/3 scale and shear-span ratio 1.5 has been done. The five medium-high shear walls include a shear wall with steel frame, a shear wall with steel truss, a shear wall with steel frame-steel bar truss, a shear wall with steel bar truss and a usual one. Based upon the experimental study, bearing capacity, the stiffness and its attenuation, ductility, hysteretic property, energy dissipation and failure phenomena of each shear wall with different design parameters were contrastively analyzed and the seismic mechanism of this kind of new shear wall has been opened out.2. Based on the experimental study, the mechanical models and formulas of bearing capacity and stiffness were established. The results obtained from the formulas and those from experiment are in good agreement. The resilience model was also been suggested.3. Some suggestions for seismic tectonic measure of shear wall with concealed steel truss have been presented. And some advice for seismic design of this kind of new shear wall has been put forward.The results of study indicate that compared with the usual medium-high shear wall, the yield load and ultimate load of medium-high shear wall with concealed steel truss are obviously higher, its yield stiffness is evidently improved, its hysteretic curve is plumper, its ductility and energy dissipation capacity have been improved remarkably. The inclined staff of the steel bar truss has a restraining function to the development of the crack, and the phenomena is that there are more crack and larger distributing area on the shear wall, which is an important token of the improved seismic capacity. Concealed steel truss has the function of increasing the height of plastic hinge area, which is another important token of the improved seismic capacity. Also the concealed steel bar truss has the function of resisting the slippage caused by shear.The seismic design suggestions put forward in this paper and the related study results can be a reference for seismic design.
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