Firstly, based on the a lot of literature datum, the current situation of the coarse materials' design theory is analyzed, their characteristics and the existing problems are pointed out.Secondly, the method and the corresponding test technique adopted by this experimental investigation is introduced briefly. According to the stress path of dam, the corresponding test was carried out. The results of the stress path is that the principal stress ratio and the stress increment ratio keep constant are calculated and analyzed, the corresponding experience formula and regularities of stress-strain are gained.Thirdly, based on the strength curves of the course materials of the test and thedocuments by regressing and analyzing, a power-function( r = Aab) , the range and theway of the solve of the parameters(A,b) are given.Lastly, according to the feature of the coarse materials' strength curves, using thestrength criterion( r = A a ) instead of Mohr-Coulomb criterion( t f = antg |