Strain rate sensitive compressive response of gelatine: Experimental and constitutive analysis

Gelatine is widely used as a soft tissue simulant in physical surrogates for the human body. Historically, gelatine has been used to evaluate penetrating impacts and, more recently, to evaluate blunt impact and blast loading effects on soft tissue. There is a need for material characterisation data across a wide range of strain rates, and appropriate constitutive relationships that can be used in models, particularly finite element models, to accurately predict the response of gelatine under various loading conditions. In this study, dynamic experiments were conducted using a split Hopkinson pressure bar and quasi-static tests performed on gelatine to investigate its compressive stress-strain response at both quasi-static and dynamic rates of deformation. The experimental results show that gelatine exhibits rate-sensitive and nonlinear behaviour. The Zhu-Wang-Tang constitutive model can adequately describe the rate-sensitive compressive behaviour of gelatine as good agreement was found between experimental results and model prediction.