beam4 和 shell41 接触怎么处理？

参加结构设计竞赛，用桐木条和油性纸做高层结构，想用beam4和shell41 进行受力分析，结果计算不出来。错误代码：
*** WARNING *** CP = 11.357 TIME= 21:29:48
Structural elements without mid nodes usually produce much more
accurate results in quad or brick shape.
*** WARNING *** CP = 11.934 TIME= 21:29:49
There are 220 small equation solver pivot terms.
*** ERROR *** CP = 11.950 TIME= 21:29:49
The value of UY at node 274 is 1.337944562E+14. 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.

命令流在附件，求指教