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RECTBEAM.xls

I was trying to find where the CRSI "Universal Column Formulas" came from. I have a project that requires the use of ACI 318-05 and I want to make sure that this sheet covers all the required items. Where can I find these equations? Thanks in advance!

mdmichiels:

The CRSI “Universal Column Formulas” are from editions of the CRSI Manual from the mid to late 1990’s. As far as I know CRSI has not republished these formulas, reflecting the change in the “phi” factor from 0.70 to 0.65. I wish that they would, because I plan to create an updated version on the RECTBEAM.xls workbook. For now, in the 2 colum worksheets my best bet is to ratio down the original “Universal Column Formulas” formulas by a factor of 0.65/0.70. Problem is, the way those equations are expressed and simplified down, it does not make it readily apparent where to make those adjustments. I will get it figured out…..hopefully.

Remember that both the ACI 318-02 and ACI 318-05 Codes still permit the use of the ACI 318-99 Code, as long as the applicable “phi” factors and ultimate load factors for that prior code are still used as a matter of consistency.

Alex

Alex,

I am assuming you are referring to the Maunual of Standard Practice. Is that correct? I have a copy of the Design Handbook from 1993 and 2002 and couldn't find any reference to these equations.

I did note that ACI 318-05 permits the use of the CRSI Handbook (2002) or the ACI design handbook (1997, which uses 318-95). Where does it make reference to ACI 318-99? Feels like I've been chasing my tail to make sure I stay consistent throughout the entire process.

mdmichiels:

No, the CRSI "Universal Column Formulas"are from the CRSI Design Handbook, 8th Edition, 1996, pages 3-225 to 3-230.

I was incorrect in my statement that the ACI 318-02 and ACI 318-05 Codes state that you may still use ACI 318-99. That is not exactly true. What I actually meant was that Appendix C in ACI 318-05 gives you the load factors and "phi" factors that can be used as an alternative. The "phi" factor for tied compression members is shown 0.70, same as in ACI 318-99, and the ultimate load factors are for the most part the same as in ACI 318-99. The main difference is that you cannot take a 0.75 reduction times the D+L+W load combination, as was allowed in ACI 318-99. As long as you use the correct load factors and load combinations from ACI 318-05 Appendix C, you can use the column worksheets from the RECTBEAM.xls workbook, because you are prompted for the ultimate factored loads, and the "phi" factor used is 0.70.

That's my take on it anyway.

Alex

Mr. Tamanovich, since you intend to update the RECTBEAM.xls workbook to ACI 318-05, can you please consider posting a metric version of the spreadsheet. The vast majority of engineers working with ACI318-05 outside the US have to submit calculations in metric.