In the present study, we use the finite element method to examine the ability of various constitutive relations to reproduce the response of a hydrated phase of hardened cement paste measured in a cyclic nanoindentation experiment. It is found that the linear viscoelastic model, which fits very well a single loading-dwell-unloading cycle, does not properly describe the subsequent cycles. Qualitatively the best results are obtained with a combined viscoelastic and plastic constitutive law. A finite element model is also employed to analyze the effect of material inhomogeneity in the vicinity of the indent. The results of the numerical study provide a valuable feedback to experiments by helping to select appropriate indentation depths and loading histories. The study also extends the knowledge about the micromechanical behavior of cement paste.
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