作者关于用abaqus进行buckling analysis得到buckling mode, 以及将buckling mode乘以magnitude作为缺陷imperfection，并且对column进行nonlinear analysis分享了整个建模的过程，分成两部分，希望能有帮助 （youtube视频）：

ABAQUS: eigenvalue buckling analysis of Cee section column under compression (1)​www.youtube.comABAQUS: nonlinear analysis of Cee section column under compression (2)​www.youtube.com

ABAQUS特征值分析https://www.zhihu.com/video/1072600395498606592

ABAQUS非线性屈曲分析https://www.zhihu.com/video/1072600872722173952

笔者对基于屈曲特征值分析，得到屈曲模态，将其作为基础引入缺陷，然后进行非线性屈曲分析的基本步骤以及注意点进行了小结，以便查阅：

Step1: Eigenvalue buckling analysis

Input the following before *End STEP

*NODE FILE, GLOBAL=YES, LAST MODE=1 ##come combine several buckling modes as the initial imperfection

U

Save U of the first buckling mode in the form of .fil

Step2: Introduce imperfection

Input before *Step #edit input file ** After STEP: Step-1 before *Step, name=Step-1, nlgeom=YES

*IMPERFECTION , FILE=Results, STEP=1

1, 1e-1

1e-1 is 1/10 of the shell thickness

Step3: Perform the postbuckling analysis.

Input the following before *End STEP

*NODE FILE, GLOBAL=YES, LAST MODE=1 ##come combine several buckling modes as the initial imperfection

U

Save U of the first buckling mode in the form of .fil

关于视频，针对特征值分析以及非线性分析的 take away notes:

Buckling eigenvalue analysis

1. material orientation definition: tools-create datum-csys-cylinderical edit material orientation using csys for different regions.

2. Define shell-composite section definition

3. Produce .fil with the buckling mode by "edit keywords" add following before *end step to: *NODE FILE U

Nonlinear analysis

1. Material failure criterion: Hashin damage criterion (this is not verified, but can give an example about how it works)

2. Step-field output- Toggle failure indicators of four Hashin damage criterion to visualize failure status.

3. Displacement control (edit displacement in the boundary condition manager)

4. Define imperfection by adding the following before **STEP (note: several buckling modes can be combined with different magnitude) *IMPERFECTION, FILE=filename, STEP=1 1, imperfection_magnitude

5. How to exact data from results and draw load-displacement curve in excel.

文档资料：ABAQUS Analysis User’s Guide

视频资料：https://www.youtube.com/watch?v=uGVfu3hK43Y