This paper describs aseismic design philosophy of buildings with maldistributed shear wall which causes the eccentricity in strength as well as in stiffness, based on energy absorption concepts obtained from inelastic torsional response analyses during sevre earthquake. Through this study, the following conclusions are derived. 1) Total plastic strain energy stored in an eccentric building is, without reference to the value of eccentricity, much the same with energy stored in a building without shear wall and non-eccentricity. 2) Torsionl response behavior of a building subjected too lateral ground motions under a condition of simultaneous imputs with two orthogonal directions can be estimated almost the same as the sum of two torsional responses where the motions are independently applied. 3) Effect of torsion. depends significantly on C_m value which is defined as a ratio of resistant moment in unforced direction to torsional moment in forced direction, where either moment is a function of frame stregth. Torsional deformation excels extremely in the range of C_m≤1, while the torsional effect can be ignored in C_m≤5. 4) Maximum ductility demand in the range of C_m≤1, _xμ_2, is calculated by use of ductility demand in the non-eccentric building, _xμ_0, as shown in eq.(14). A value of _xμ_2/_xμ_0 highly depends on a value of λ, which is a ratio of side length of orthogonal to parallel against the horizontal force direction. When the value of λ exceeds one, _xμ_2/_xμ_0 becomes greater than one in general.
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