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In conventional methods of dynamic analysis. the response of structure is computed only for three uncorrelated translation motions. However. due to
phase difference between the motion of
ground points and scattering of waves in presence of foundation, in addition to transitional motions, three rotational motions are generated (Namely, two rocking components and a torsional component). Most studies have considered torsional component and very few reports are available on rocking components. In this paper, the correlated rocking motion is computed based on the three assumed uncorrelated translation motions which arc recorded from past events. Considering this component as a base motion, its effect is then studied on different buildings. It is shown that the effect of the rocking motion on irregular buildings is more important than the regular ones. Also its effect on the bracing forces and the columns moments are evaluated.