Three reinforced concrete plane frames with total heights of 6

10

and 16 stories

respectively were taken as examples. Nonlinear dynamic responses of three frames under excitations of seven earthquake waves with varying earthquake intensities were selected as the datum mark of a comparison study. The changing rules of the responses analyzed by four kinds of ordinary Pushover Analysis and Modal Pushover Analysis were studied by reviewing the interstory drift ratio and rotation at beam and column ends. Results show that the error of interstory drift ratio analyzed by Modal Pushover Analysis essentially is invariable when the total frame height increases

while the error of ordinary Pushover Analysis is added corresponding to a larger fundamental period. This indicates that Modal Pushover Analysis can cover the influence of higher modes more reasonably. When nonlinear responses of frames were more severe

the interstory drift ratio errors of Modal Pushover Analysis and ordinary Pushover Analysis also increase correspondingly. The errors of rotation at upper story beam ends and the majority of column ends analyzed by Modal Pushover Analysis are smaller than those of ordinary Pushover Analysis.