The particle breakage has a great influence on the deformations of a rockfill body. Apart from the strength of parent rocks

stress state of rockfill is losely related with the particle breakage degree. Most of the deformations of a high rockfill dam is a reflection of particle breakage under high stress state. Although NHRI’s double yield surface model puts forward by Shen Zhu-jiang (member of CAS) well reflects the deformability of rockfill

the model can not adequately reflect the shear shrinkage induced by particle breakage. So the deformation calculated by NHRI’s model is usually smaller than the real one

and therefore NHRI’s model is only applicable to stress-strain analysis for medium and low rockfill dam. Based on NHRI’s double yield surface model

a numerical analysis method considering strain effects induced by particle breakage is presented in this paper. The method can better reflect the deformability of rockfill. So its calculation result is more reasonable for rockfill dams

especially the high rockfill dam.