Abstract:

To obtain the conditions for taking the t0p-floor of the basement as the fix．end of the superstructure.the dynamic calculating models of high-rise building structures with basements are discussed. The dynamic characteris-tics of shear buildings,bending buildings,shear-bending buildings and bending-shear buildings with basements are then respectively calculated and analyzed.Moreover,the effects of the mass and rigiditv of the basement on the free vibration period are investigated.The results demonstrate that,for all high-rise bending buildings,most high.rise shear-bending/bending-shear buildings and the high-rise shear buildings with a little ratio of basement shear rigiditv to standard shear rigidity,that is,less than 2,the effect of the basement cannot be neglected in the dynamic calcu-lation,and that the top slab of the basement cannot be taken as the fix.end of the superstructure

Key words: high-rise building structure, basement, dynamic calculating model, lateral rigidity, free vibration pe-riod