Out of systematic analysis on earthquake response of tall buildings by digital electronic cornputers, variations in response of 20 storeied structures caused by the difference of rigidity distribution, of earthquake forces and of restoring force characteristics are presented. (Serial mass-spring systems which correspond to steel and R.C frames are used as models for calculation.)

* Manuscript received on May 8, 1964.
** Research Member of B.R.I , Ministry of Construction