Abstract：Three methods for analyzing hydraulic fracturing of earth-rockfill dam core are described and compared，i.e. total stress method，synthesis method and conventional effective stress method. The merits and limitations of those methods are discussed. The analyses of hydraulic fracturing for Pubugou earth dam and Lianghekou earth dam are carried out using these methods；and the differences in these methods are investigated. The rationality of synthesis method is demonstrated. Some rational criteria of hydraulic fracturing for the total stress method and the synthesis method are suggested；and the shortage and improvement of the conventional effective stress method are pointed out. A new factor of safety for hydraulic fracturing is defined；and it can be conveniently used to assess the safety of dam core hydraulic fracturing. The newly defined factors of safety from different methods are used to check the capability of Pubugou earth dam to prevent hydraulic fracturing. The safety of against hydraulic fracturing for the two dams is confirmed.
