abaqus警告信息求高手解答

***WARNING: SOLVER PROBLEM. NUMERICAL SINGULARITY WHEN PROCESSING NODE
MAODONGMOXING-1.404 D.O.F. 1 RATIO = 5.05319E+15.

***WARNING: SOLVER PROBLEM. NUMERICAL SINGULARITY WHEN PROCESSING NODE
MAODONGMOXING-1.571 D.O.F. 2. THIS NODE HAS NO STIFFNESS IN THE
SPECIFIED DIRECTION AND IS NOT COUPLED WITH THE REST OF THE MODEL.

***WARNING: SOLVER PROBLEM. NUMERICAL SINGULARITY WHEN PROCESSING NODE
MAODONGMOXING-1.404 D.O.F. 2. THIS NODE HAS NO STIFFNESS IN THE
SPECIFIED DIRECTION AND IS NOT COUPLED WITH THE REST OF THE MODEL.
***WARNING: SOLVER PROBLEM. ZERO PIVOT WHEN PROCESSING NODE 404 INSTANCE
MAODONGMOXING-1 D.O.F. 1
查了一下资料
第一条是出现在约束1方向出现刚体位移，第二是约束2方向没有刚度。然后模型里加弹簧支座，但是计算后，第二条还是存在，求高手解答。