In Viscoelasticity material modeling there is only shear and bulk modulus option with time. There is no option for creep compliance for young's modulus with time. Can I convert the Young's modulus to shear modulus using G=E/2(1+v) equation or I have get shear data from test to run the analysis? Is young's modulus is not required in creep because it is shear dominated phenomenon? I am working on short fiber composite, where equation above may not work because there are two phases. I want to know if i should get shear compliance data or Young's compliance modulus data for modeling viscoelastic behavior.
Please advice!
