Study of seismic safety of Changheba high rockfill dam with earth core

Three-dimensional nonlinear finite element analysis is carried out to explore the dynamic properties and seismic safety of the dam on the basis of static calculation.The filling materials of this dam and alluvium deposit are simulated by the Hardin-Drnevich constitutive model that could consider the effect of confining pressure.Softening modulus method is carried out to calculate the permanent deformation of the dam with residual body strain and residual axial strain calculation formula that could consider the effect of confining pressure.The results demonstrate that:There is a significant seismic dynamic response of the dam during the earthquate.A significant earthquake permanent deformation has taken place on the dam crest with a biggest settlement of 140.6cm,which is 0.59%of the maximum dam height.The accumulation time of stability safety coefficient less the 1.0of both the upstream and downstream is 2.56sand 2.76sdurning the calculation of 30s.The dynamic strength safety coefficient of the upstream filter layer 45maway from the crest is less than 1.0.The corresponding proposals are put forward for the design of the project according the calculation results.