Relation between G0, Eur and υ

When inputting values of soil.I have questions about the accurate relation between G0, Eur and υ. When  changing the value of Eur to 1, it will say Eur>2E50 and G0 must be less than 8.33. When setting the value of Eur too high(for example,100E3), it will say Eur<20*E50 and G0 must be bigger than 41,67E3. That means there exists some accurate relation between these 3 variables.

So I look up the Material-Models but I can't find any accurate relations.

So can anyone help? I will appreciate.