I'm using tapered steel sections in STAAD PRO V8i and the design output has warning of "tapered beam design output restricted to track 0". My question is what is the design implication of this warning and how can I remove this?
As per the British Steel Code, the tapered beam design is limited to TRACK 0 only. The detailed result is not available as we are in the process of improving the Tapered Beam Design.As of now, we suggest you not to use Tapered Beam design option till the modifications are completely implemented.
As a workaround you may created such beams from the Crete User Table>> General Option.
Q: Hi Shany, thanks for your reply. Just to add to my inquiry on tapered beam, I am getting "pass" result on the staad output file, does this mean I can trust this design output even it has warning?
On your suggestion to create user table, I have made it as well but the same warning is shown on the staad output
A:
The warning in itself is not going to affect the design. The warning merely suggests that the output is restricted to TRACK 0 only.
However, the technical support group has not been fully happy with the implementation and had reservations regarding particular sections of it. Accordingly, we have asked the development team to do a review and we do not suggest the use of tapered member implementation until the review is complete. We suggest you to split the members having tapered sections and assign the average properties to each bit.
Hi Shany,
Sorry to extend this thread as my query is exactly the same topic as above.
You said that for STAAD to analyze a tapered section, we need to split the members into several parts with uniform cross section using the average properties.
Now, my simple question is, can we model the tapered section by multiple elements but with varying cross sections from start to end node? Will the more realistic model approach be considered? Please see image below.
Thank you very much!
Mac
Master Mac,
You wrote :You said that for STAAD to analyze a tapered section, we need to split the members into several parts with uniform cross section using the average properties.
Our response:No, not always. There are certain types of tapered sections that STAAD is equipped to handle. For such sections, you have to specify the cross section dimensions at start, and at the end, and, the program will do the rest. I-shaped sections (section 5.20.3 of the Technical reference manual), and several types of tubular sections explained in section 5.20.2.1 of that manual fall in this category.
If the section you wish to model is not one of these types, then, what you have said is true. In such case, you can do one of the following:
a) Model it using a number of line segments, each segment having a uniform (non-tapered) cross section. The section dimensions will change abruptly from one segment to the next.
b) Model the member as an assemblage of plates. For your tapered steel box, each side of the box will have a set of plates like you have done in the figure you attached. So, what you have done is correct.
Note: If the box is square instead of rectangular, you can define it using the method described in section 5.20.2.1 of the Technical Reference manual. Example,
MEMBER PROPERTIES3 PRIS SQUARE STA 12 END 8 THI 0.375
RAJAT
Hi,
Actually most of our steel members are tapered box section (see section image below) and the sample model above was a beam divided into multiple segments each with respective properties as required by STAAD - USER TABLE-GENERAL PROP. We are doing this in repetitions and i just want to be sure that our assumption/procedure is acceptable. I understand that STAAD wasn't able to design tapered steel section but still can help us in the analysis and determination of member forces and resistances.
Thank you for your time answering my question and for the clear explanation which helps me to understand better how STAAD deals with tapered steel section. Also thanks to this Community!
Cheers,
Master Mac
Hello Mac,
The procedure you are following will not hamper your analysis results.