The failure process of rocks by freezing and thawing cycles cannot be fully understood. However, it isvery important to confirm this process for the assessment of durability of material rocks for use as riprap ofrockfill dams. The auther has been conducting laboratory freezing and thawing test on material rocks to confirmthis process. From a series of tests, the following results have been obtained.
1) The number of freezing and thawing cycles to failure (The auther defined this cycles as freezing andthawing life) shows wide fluctuation and this phenomenon is an essential properties of the failure process ofrocks by freezing and thawing cycles.
2) Exponential, log-normal, Weibull, McCall and gamma distributions are all applicable to describe thedistribution characteristics of freezing and thawing lives of rocks.
3) From the distribution characteristics of freezing and thawing lives, and the change of physico-mechanicalproperties, it is concluded that the failure process of rocks by freezing and thawing cycles is serial andcumulative like the fatigue failure process of metal.