SEAOC Volume 3 Page 305 Grade Beam Mpr? A few errors to report in text...

[McEngr]

Page 305 has a probably Moment capacity (Mpr) of 2860 ft-kips. Can someone give me a brief help on how they come up with this? It seems I could solve it just like they do on previous pages, but there's very little info in the SEAOC.

Would I sum up the moments from grade beams 46 and 47 and divide by half of the column length 29 since there is no column below? I'm clueless on this one and don't like accepting info without understanding it.

Thanks in advance for anyone willing to take the time and study concrete with me...

 

[McEngr]

Also, can someone explain why Seismic and Wind Forces by Alan Williams omits the requirement of chapter 21 transverse column shear reinforcement? This seems like a huge error unless I am missing something!

VE is clearly larger than half of VU. Correct? This is plainly stated in ACI 318-08 section 21.5.4.2.

 

[McEngr]

Another errata that I can tell in SEAOC Volume III:

Page 313 - Ajis shown pictorally in the ACI 318-08 fig R21.7.4. The Aj of the beams seem incorrectly applied since the shear would have to be limited by the beam size itself. Can someone explain to me how Aj can be bigger than the Abm?

Page 314 mentions column depths of 42 and 40 inches. The columns are clearly 36" deep.

Another side note on the Wind & Seismic Design Examples (Alan Williams) - much better illustration of hoop and seismic transverse reinforcement in the beams than in the SEAOC manual. However, the SEAOC does a much better job of illustrating a column that undergoes transverse reinforcement. For SMF Columns: use SEAOC Vol 3, for SMF Beams, use Alan Williams text.