| Abstract: | The paper presents a continuum method for dynamic analysis of asymmetric tall buildings with uniform cross-section in which the horizontal stiffness is provided by shear walls and columns of arbitrary shape and layout, coupled by horizontal beams. The equations of motions are formulated in variational terms, including axial strain energy. Numerical solutions, obtained by using finite time differences and infinite polynomials, are presented for the response of a twenty-storey building with six shear walls to an impact load and earthquake accelerations. It is shown that omission of the axial deformations results in a substantially distorted pattern of behaviour, some of its effects being: - 1 Overestimation of the bending stiffness of the coupled shear walls, with corresponding changes in their stiffness ratios.
- 2 Underestimation of the periods of the principal modes, with a corresponding change in the dynamic response.
- 3 Distortion of the magnitude, form, time of onset and coupling of the maximum displacements.
- 4 Pronounced change in the shear force and moment diagrams for the shear walls, the beams and the building as a whole.
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