Compressive Mechanical Properties and Constitutive Model of Rubber Material

The compressive properties and constitutive model of silicon rubber were studied. Quasi-static and dynamic compression tests were carried out using an Instron-8872 universal machine and a modified Hopkinson pressure bar experiment device. The mechanical behaviors of silicon rubber materials at six different strain rates (0.001、0.01、0.1、1750、2300、3000 s⁻¹) were analyzed. The results show that silicon rubber has significant hyperelastic properties under static load and exhibits remarkable strain rate effects under dynamic load. There is a nonlinear relationship between elastic modulus and logarithm of strain rate ratio. Based on this, a constitutive model with a strain rate term was established to describe the mechanical properties of silicon rubber under static and dynamic compressive loads. Compared with existing models, the established five-parameter constitutive equation has the advantage of simple form. The maximum error within the strain range is kept within 15%, which is in good agreement with the experiment results.