A simple model for elastic and viscoelastic punch indentation problems   with experimental validation
  This paper presents an analytical model of punctual elastic contact between a rigid body of arbitrary geometry and a plane surface. A simple analytical model is developed in order to evaluate the contact force knowing the volume of interpenetration, the surface and the perimeter of the base of this volume and the mechanical characteristics of surfaces in contact. Analytical and experimental validations are made for this model in the case of simple shapes (spherical, conical and pyramidal). Next, an approach for the resolution in case of contact between a rigid body and a viscoelastic plane is presented. The elastic constants are replaced by an integral operator corresponding to the viscoelastic stress-strain relation. At last, the viscoelastic punctual contact is studied analytically and validated experimentally. 
Abdelaziz Sameur, Honor\'e Yin, Denis Duhamel, Vladimir Vilke