etabs 运行分析出现警告 负刚度 特征值

在etabs运行分析日志中出现
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NEGATIVE STIFFNESS FOUND DURING SOLUTION FOR DOF RY OF JOINT15546
LOCATED AT X =4226.080, Y =14392.368, Z =13500.000,
STIFFNESS MATRIX DIAGONAL VALUE = -4.6060E+07,
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NEGATIVE STIFFNESS FOUND DURING SOLUTION FOR DOF U1 OF CONSTRAINTAL2
LOCATED AT X =-1374.846, Y =-9837.165, Z =4100.000,
STIFFNESS MATRIX DIAGONAL VALUE =-1.449953,
还有
我做了一个10层的框剪模型，进行模态分析，指定振型数是12个，运行完毕后出现这样的警告：
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EIGENVALUE12 WAS FOUND OUT OF SEQUENCE
这两个问题，不知道是什么意思，该如何解决？
请问出现的原因及解决办法？麻烦各位 不吝赐教谢谢！！！