Abstract: Based on the peak-load method, a simple way for getting fracture parameters of the fully-graded hydraulic concrete of a super-high arch dam is proposed. Using the finite element method, the formulas of stress intensity factors K, crack mouth opening displacement CMOD and crack opening displacement COD profile were determined for the non-standard wedge splitting specimens of fully-graded hydraulic concrete. The effective fracture toughness and critical crack tip opening displacement CTOD_c were experimental determined by proposed formulas. The successful use of non-standard wedge splitting specimens with different size but same in ratios of notch length and effective height reveals a great potential of the peak-load method in fully-graded hydraulic concrete. One only needs to measure the peak loads of distinctive specimens, and the fracture parameters of the fully-graded hydraulic concrete can be easily determined.