*** ERROR ***                           CP =      22.480   TIME= 22:45:48

 The value of UY at node 5989 is 476303840.  It is greater than the      

 current limit of 1000000.  This generally indicates rigid body motion   

 as a result of an unconstrained model.  Verify that your model is       

 properly constrained.                                                   

 *** ERROR ***                           CP =      22.620   TIME= 22:46:04

 *** MESSAGE CONTINUATION ---- DIAGNOSTIC INFORMATION ***                

 If one or more parts of the model are held together only by contact     

 verify that the contact surfaces are closed.  You can use the CNCHECK   

 command to check the initial contact status in the SOLUTION module.     

這是在ANSYS中進行螺栓預緊力分析，出現以上兩處錯誤，不知道是接觸問題還是邊界條件問題或者是預緊力的加載不對，懇請有經驗或懂的大神指點一下，謝謝！