Model CHECK Clear relation

From what I can see there is no such capability, probably because it is dangerous. Removing all the relations in a model without knowing what they do could screw up any number of things. For example, I often use relations to define the description of a part that will be put into a bill of materials. A shaft might have relations that define a retaining ring slot's dimensions based upon the part's diameter. There are lots of cases where the relations are what makes the model correct, particularly if a top-level assembly is being used to drive the component dimensions.