contact between 2 surfaces

Hello everyone,

I am trying to analyze 2 objects in contact. the first object is wrapped around the second object like 2 concentric circles. the first time i ran this analysis, i applied a pressure force on the outer circle and checked the stresses in the inner circle. the results came out fine so i assume my contact interactions and boundary conditions are not a problem. I am now trying to rerun the analysis but instead of applying a force to the outer ring, im applying a negative strain to simulate material contraction of the outer ring around the inner ring. in reality, this should create a stress on the inner ring. however, in the results, the contact stresses in the inner ring are all 0. i also checked the contact status and it says they are all open.  

does a strain not count as something than can cause contact to occur ?

thank you