Viscohyperelastic Material Modeling of Liver Tissue

Mechanical characterization of soft tissue plays a critical role in applications such as automated surgery, disease diagnosis and tissue engineering. Soft tissue is often modeled as an isotropic incompressible and hyperelastic material. However, it is well known that viscoelasticity plays an important role in determining the response of soft tissue to mechanical loads [1]. This work is concerned with the development of hyperviscoelastic models of soft tissue in general and liver tissue in particular. Experimental studies in uniaxial compression are conducted on bovine liver tissue at strain rates between 0.001 s⁻¹ and 0.04 s⁻¹. The response of liver tissue is modeled using the continuum mechanics framework using an exponential form of the strain energy function.