I have been analyzing a model for pushover analysis. I have roof bracing of HSSP members which STAAD does not recognize as a circular type & I keep getting error messages that I need to model these as circular section (which they are already!). I end up re-modeling these as PIPE. STAAD then forces me to change some of these to W or T or channel shape as I keep getting error message " ***ERROR : ONLY WIDE FLANGE, TEE, AND CHANNEL ARE ACCEPTED AS BEAM/COLUMN IN PUSHOVER ANALYSIS. " although these are not beams or columns but roof or wall plane bracing. I ran the program & kept changing these individually to W shape (for sake of making the program run). Although if I ever mange to finish the design of the structure it has no resemblance to my original with all these force changes due to STAAD PUSHOVER ANALYSIS Package bugs & limited capabilities. In the process of changing these bracing to a type that Staad Pushover accept & let it run I get a new message which I have not seen before namely "EXCEPTION (ACCESS VIOLATION) RAISED! ABORTING ANALSIS".
Can some one let me know how to resolve this?
Can you please attach the model? We need to look into the model.
Please note that STAAD force me to change all my bracing to Pipe & then some of these to Wide flange. It keep giving error message beam by beam & force me to change member type to Wide Flange & then I got the final fatal error. Here is the file. I did not know how to attach it as a file
This is another model done for testing the Pushover and I get an error " **ERROR : MASS PARTICIPATION IS LESS THAN 75 PERCENT IN PUSH LOAD DIRECTION. FURTHER ANALYSIS IS STOPPED". In order to resolve this issue I change the ridge point coordinate (i.e. node 5) from 6m to 8m, then I get I get the violation Error ""EXCEPTION (ACCESS VIOLATION) RAISED! ABORTING ANALYSIS".
I have two question 1)How do I resolve the Participation issue? 2) How do I resolve the Violation error.
Furthermore the program does not run if I change the structure to a braced frame instead of Moment frame (by introducing hinge at ridge & adding bracing" with the error **ERROR : MASS PARTICIPATION IS LESS THAN 75 PERCENT IN PUSH LOAD DIRECTION. FURTHER ANALYSIS IS STOPPED"
Here is the file
There has been a problem in the Pushover analysis and that is the reason why you have faced this problem. Developers are working on that. In this model, I have used partial moment release and the program is able to analyse the model. Please fid the attached revised model. It is worth mentioning that the program can only handle wide flange, channel and T sections in pushover analysis. So, I changed the HSS and pipe section to channel section.
Mohandes,
If you run your first model with the command
PERFORM BUCKLING ANALYSIS
the buckling factor for the first mode is reported as 1.04. It means that the applied loads in your model are very close to the capacity of the structure calculated from a linear buckling analysis.
By changing the full releases to partial releases as DSANJU has suggested, the buckling factor for the first mode goes up to 1.63. The revised model that he has provided represents a structure that is more stable.
If you look at the portal frame I posted for testing Staad Pushover. If I increase the coordinate of the ridge at node 5 I get the "Exception [Access violation]Raised! Aborting Analysis" error which should have nothing to do with partial release of joint as I have done that on this simple portal frame & I still get the same error. The original issue is that I have a structure that need to be checked for Pushover. I should not be force to change my structure to suite STAAD Pushover short coming as far as Members selection is concern. I have designed & optimized my structure for all Load combinations. I was hoping that Staad will be able to analysis the same structure for pushover. Changing the structure to match Staad Pushover shortcoming results in a structure that no longer match my original design & the whole pushover exercise using Staad in this way is futile. I may need to find an alternative program which can check my existing structure for push over & does not force me to modify it to suite the analysis package.
Thank you Kris. It solves the fatal error but I have left with a structure with so many member different from my original design that either I have to re-design and change my building to the same member type that Staad Pushover accept which is not what I can do as we have all our building with circular section for bracing which staad does not like. So need to find an alternative program which does what is expected rather than staad which is a) not up to date to the latest code ASCE 41-06 rather than outdated FEMA356 b) limit in which member type can be used & C) if you lucky program works without any fatal error.