| In the design of tall building, the dimension of upper part of shear wall would be reduced, and even the upper wall would be cut, due to the architecture demand or other reasons. The frame-shear wall structure with shear wall interruption is a new type of tall building, its characteristic is to meet the function of modern tall building by shear wall interruption. The deformation of shear wall is the type of cantilever bending beam, but the deformation of frame is the type of cantilever shear beam. The lower part of shear wall can decrease the internal forces of lower part of frame; but upper part of shear wall can increase the internal forces of upper part of frame. It may be rational to cut the upper part of shear wall and to reduce the internal forces of the upper frame. Therefore, in the view of mechanics, the full height of wall is not necessarily imperative. Based on the disformation characteristic of the frame-shear wall structure cooperation work, the rationality of the frame-shear wall structure with shear wall interruption is discussed. The 3 conditions of interruptable shear wall height are established:①The top lateral displacement of the frame-shear wall structure with shear wall interruption is less than top displacement of the frame-shear wall structure with full height shear wall.②Interstorey drift as a percentage of height above the shear wall interruption is less than 1.45 times of maximum interstorey drift in the structure with full height shear wall, because it is stipulated in code for seismic design of buildings (GB50011-2001): elastic interstorey drift in frame [θe] =1/550; elastic interstorey drift in frame-shear wall structure [θe] =1/800, the ratio between them is 1.45.③The seismic shear force Vt of frame above the shear wall interruption is less than n times of maximum seismic shear force V fmax of frame in the structure with full height shear wall, n is the ratio of column number above the shear wall interruption to the column number in the structure with full height shear wall.The concise storey element is fabricated which can model one storey of the frame-shear wall structure. Based on SRSS method, both storey element model and the member-relative storey model are used to analyze the seismic response of frame-shear wall structures with shear wall interruption for different heights and rigidity characteristics. Two models give the similar results. According to 3 conditions of interruptable shear wall height, calculation results indicate: with the increase of the rigidity characteristic, the interruptable shear wall height increases also. The equation between the rigidity characteristic and the interruptable shear wall height is also presented. The height of the structure influences little on the interruptable shear wall height.Based on the relationship among axial force–bending moment–curvature of the concrete bar section, the nonlinear finite element method considering bar P–Δeffect and shear deformation is established which is able to analyze the ultimate state. The improved capacity spectrum method is put forward, where the unique ductility factor of concrete frame is defined, and the point of ultimate state in pushover curve is regarded as the demand point. On the condition that the demand point locates at the inelastic demand spectrum curve reduced by ductility factor, the maximum seismic spectrum acceleration is obtained to evaluate the seismic behavior of frame. Balancing load carrying capacity, it's concluded that the frames with 0.25~0.35 relative depth of compressive zone and 0.6~0.8 axial compressive ratios perform benign seismic behavior.Based on the above nonlinear finite element method, regarding the shear wall as the special bar elements, the frame-shear wall structures with shear wall interruption for different heights, reinforcements, axial compressive ratios and rigidity characteristics are analyzed by static elastic-plastic method. According to 3 conditions of interruptable shear wall height, calculation results indicate: the interruptable shear wall height is not relative to reinforcements and axial compressive ratios, little relative to height of the structure. With the increase of the rigidity characteristic, the interruptable shear wall height increases also. The equation between the rigidity characteristic and the interruptable shear wall height is also presented.There remain two kinds of Wilson-θmethods, namely, Wilson-θ①and②methods. In Wilson-θ①method, the accelerations are not modified by the dynamic equilibrium equations; in Wilson-θ②method, the accelerations are modified. The amplification matrixes of Wilson-θ①and②methods for single-degree-of-freedom system are derived. The stabilities of Wilson-θ①and②methods are examined by the spectral radii of the amplification matrixes. The stability of Wilson-θ①method is unconditional. The calculation results indicate: the stability of Wilson-θ②method is not unconditional. The stability ranges of Wilson-θ②method are also put forward. The conclusion corrects an error in some references in which both Wilson-θ①and②methods are wrongly considered as unconditional stability.Based on the member-relative storey model, Wilson-θ①method and EL Centro ground motion record, the seismic response if frame-shear wall structures with shear wall interruption for different heights and rigidity characteristics are analyzed by time history method. According to 3 conditions of interruptable shear wall height, calculation results indicate: with the increase of the rigidity characteristic, the interruptable shear wall height increases also. The equation between the rigidity characteristic and the interruptable shear wall height is also presented. The height of the structure influences little on the interruptable shear wall height. The conclusion of dynamic time history analysis is similar to the conclusions of storey element model, the member-relative storey model and static elastic-plastic method.
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