壳体结构冲击模拟 壁厚为什么会减小？

Dear all, 
  
I'm now simulating tube crushing with Abaqus/Explicit. The tube is meshed with shell elements, and general contact is used for contact. As the mesh goes finer, the thickness of elements reduces and there's a warning message as follows: 
  

In step 1, some facet thicknesses for general contact were reduced

            from the parent element or specified values due to a large

            thickness compared to facet dimensions.  The most significant

            thickness scaling factor was 0.69815 for a facet on parent element

            53801 of instance QQQQ-2.  An element set named

            "WarnElemGContThickReduce" has been created to locate the regions

            of reduced thickness.

 
  
I know that such thickness reduction is required by the contact simulation, but can anyone give some comments on to what extent such reduction will influence the final results? and is it possible to know the amount of thickness reduction for each element whose thickness has been reduced. (As the warning message only gives the most significant reduction value). 
  
Many thanks and kindly regards, 
  
XIAO.K