Creep deformation of rockfill has relations with not only load but also wetting-drying cycle

which is caused by solarization and rainfall.Test was taken to simulate the wetting-drying cycle effect caused by solarization and rainfall in laboratory

which is done to study the influence of wetting-drying cycle on rockfill longtime deformation.Test result shows that deformation caused by load function tends to be stable quickly and occupies only a small part in total creep deformation

while the creep deformation caused by wetting-drying cycle is huge and long-time developing with cycles.It takes about 50%～70% in total creep deformation

and has relations with stress.So it has major impact on dam′s stability and safety.According to the analysis of wetting-drying cycle creep principle

numerical model is put forward to calculate the deformation by wettingdrying cycles

and it can be applied in finite element analysis.