Material Nonlinear analysis using SAP2000
Material Nonlinear analysis using SAP2000
(OP)
I want to do material nonlinear analysis using SAP2000. But I have a doubt whether the SAP2000 actually follows the material nonlinear curve. To check that one I created a simple model (one end fixed and other end free, vertical column), then I applied different compression forces and checked whether the actual stresses and strains in the model were according the given nonlinear material curve.
In the elastic region, stresses and strains in the model were on the defined stress-strain curve(follows the stress-strain curve)
But I found following problems in the nonlinear analysis.
Problems
1)Beyond the yield point (when I increase the load), actual stresses and strains in the model were not on the curve (model doesn't follow the stress-strain curve in the plastic region).
2)For very high loads such that stresses are higher than the maximum allowable stress in the curve, still model run without any warning messages or collapse of the model.
3)For both linear and nonlinear analysis, I found same results for a given load.
In the elastic region, stresses and strains in the model were on the defined stress-strain curve(follows the stress-strain curve)
But I found following problems in the nonlinear analysis.
Problems
1)Beyond the yield point (when I increase the load), actual stresses and strains in the model were not on the curve (model doesn't follow the stress-strain curve in the plastic region).
2)For very high loads such that stresses are higher than the maximum allowable stress in the curve, still model run without any warning messages or collapse of the model.
3)For both linear and nonlinear analysis, I found same results for a given load.





RE: Material Nonlinear analysis using SAP2000
RE: Material Nonlinear analysis using SAP2000
RE: Material Nonlinear analysis using SAP2000
RE: Material Nonlinear analysis using SAP2000
RE: Material Nonlinear analysis using SAP2000
Even though I did the geometric non linear analysis (with small deformations) I couldn't see any different in the results.
When I did the geometric non linear analysis (with large deformations), I could observe slightly changes in the results.But still model doesn't do material non linear analysis.
Then I assigned a hinge to the column and did my analysis.I found that the software does the non linear analysis only at hinge but not in the entire element.
If you have any suggestions, please kindly inform me.
RE: Material Nonlinear analysis using SAP2000
good luck
Rubber engineering