Influence of pressure and density on the rheological properties of rockfills

Abstract

Long-term deformations of rockfill dams can be related to the type of dam, the pre-compaction achieved during the construction of the dam, the history of loading events, the rheological properties of the rockfill material used, the seepage behavior caused by defects of the sealing, the interactions of the dam building with the foundation, and the hydrothermal phenomena of the stressed rockfill material. The present paper investigates the rheological properties of coarse grained rockfill materials using a hypoplastic constitutive model. Particular attention is paid to wetting deformation under different deviatoric loading states and pre-compactions. To quantify the state of weathering a so-called “solid hardness” is used in the sense of a continuum description. It is shown that an appropriate modeling of wetting deformations requires a unified description of the interaction at least between the state of weathering, the stress state, the density and the rate of deformation. The results obtained from the numerical simulations are compared with available experimental data for a rockfill material used in Xiaolangdi earth dam.

Keywords

rockfills / solid hardness / wetting deformation / hypoplasticity / creep

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Acknowledgment

This work was partially supported by the National Natural Science Foundation of China (Grant No. 51179059) and the Fund for Young Scientists in Nanjing Hydraulic Research Institute.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg