The incremental dynamic analysis（IDA） by now is the most accurate method among all prediction methods which are used to assess the seismic collapse risk of RC frames. However

the IDA is too time-consuming to be used in real engineering. Simplifying the seismic collapse risk assess process is studied recently so as to improve efficiency for application. But there is lack of evidences to ensure the accuracies of different simplified methods. This work introduced three published simplified methods. The method based on the pushover analysis and the capacity curve; The method based on the pushover analysis and using the correlated relations between the collapse margin ratio（CMR） and the displacement margin ratio; The method based on the collapse resistant capacity spectrum. The collapse margin ratio and collapse risks subjected to severe earthquakes of 6 reinforced concrete frames are evaluated using the simplified methods and compared with the results of IDA. The results indicate that the most accurate method of the three is the method based on the pushover analysis and the capacity curve

and the more simple and convenient methods are the method based on the pushover analysis and using the correlated relations between the collapse margin ratio（CMR） and the displacement margin ratio and the method based on the collapse resistant capacity spectrum.