| Short-leg shear wall are transition members with specific properties between special-shaped columns and shear walls, has its own inherent characteristics. But it was seldom applied in earthquake hazardous zones, and lack of deep investigation and practical tests. For security reasons, 'Technical specification for concrete structure of tall building' (JGJ3-2002) applies more strict regulations for its seismic design. Study on the earthquake-resistant capability of shot-leg shear wall can provide essential foundations for its seismic design and perfect correlative regulations in the specification.In this paper, through analysis and study of low-cyclic loading experiments of 6 T shape short leg shear walls,the section strain relations and ductility characteristics are discussed and the valuable results are achieved. All of these provide reliable basis for the short-leg shear wall structure.In dynamic analysis methods, precise time-integration method has the advantage of high precision, but it is difficult to calculate inverse matrix or inverse exist if apply the precise time step integration method directly toshort leg shear wall structural dynamic analysis. Therefore it is a meaningful work to develop new dynamic time-history methods based on the advantage of precise exponential matrix algorithm of precise time-integration method and apply them on seismic analysis of short-leg shear wall structure.Based on those, some work has been done as follows:1. Through the low-cyclic loading experiments of 6 T-shape short leg shear walls with 1/2 reduced ratio, has revealed the strain relations section of the trend curve.2. T-shape shot-leg shear wall because of the geometric cross-section asymmetric, leading to the specimen force and energy of the asymmetry, the asymmetry of shot-leg shear wall is analysed. The influencement of asymmetry to structure design is point out. 3. Research on Aseismic Capability of shot-leg shear wall and the strain ductility factor were derived for calculating the specimen of ductility. The measure to improve nonsymmetry of ductility is suggested.4. According to hysteresis loop on the yield and limiting lag loops the abstract model of the skeleton curve of restoring force model, according to their characteristics, asymmetric two broken lines of the restoring force model is adopted. Clough model of the parameters according to cross-section of the geometric shapes, sectional reinforcement and statistical analysis of the Experimental Data is obtained.5. The Precise time step integration method (PTSIM) is much easier to be understood by complete and detailed derivation. The PTSIM based on numerical integration is analyzed and validated overall, and numerical integration of upper calculation efficiency for PTSIM is selected.6. The Newmark-βand Wilson-θmethod and renewal precise direct time step integration method are applied to elastic and elastic-plastic seismic analysis of short-leg shear wall structure whose results are compared with those of Newmark-βmethod and Wilson-θmethod. The developed program of MATLAB is able to draw displacement curve, speed curve and acceleration curve of the building under earthquake actions. Inter-story displacements and the happening time of inter-story maximum displacement and shear force can be gained.7. The results of example show bottom strengthened stories should be set and restrained edge members should be installed in walls intersection when short-leg shear wall structure is designed. High-rise building should not be all shear wall structures of short-leg shear wall in real engineering because the stiffness of short-leg shear wall structure is smaller than that of general shear wall structure and its inter-story displacement is lager. When short-leg shear wall is more in a high-rise building, barrel or general shear wall should be set. Then the shear wall structure is formed to carry horizontal loads by barrel and short-leg shear wall.
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