A Peridynamic Simulation of Nanoindentation on the Cement Mortar Interface

In order to analyze the influence of interfacial transition zone (ITZ) on the mechanical properties of cement based materials, a peridynamic approach for simulating the nanoindention procedure on the cement mortar interface was constructed. In this approach, the cement and sand were considered as discrete particles with certain mechanical properties on the nanoscale. And the interaction force functions for different components in the interface were represented by combining the van der Waals force and the peridynamic force. In nanoindentation simulation, a rigid spherical particle with constant modulus was located in the center of the interface model under pressure,the displacement distribution diagram, energy distribution diagram and the relationship between the force and displacement of the indenter were obtained by giving different values of the elastic modulus,the mechanical properties of the interface transition zone were analyzed on the nanometer scale. The results show that there is a sensible difference of energy distribution of the cement and mortar, the energy value of mortar is greater than that of of cement; the mechanical properties of the interfacial transition zone are closely related to the properties of the matrix materials, which verify the fact that the mechanical properties of the interfacial transition zone of cement mortar are relatively weak.