NCEES civil sample questions, #515 in structural

[user 788]

I figured the effective width of the footing would be B' = B-2e.

How did they come up with B' = 3(B/2 - e) ?

Also, to find p max I would have used equation 36.20 in the CERM which is (P/BL)(1+6e/:beerchug:.

Why did they use 2P/A. What's the 2 ? The safety factor ?

 

[gipper]

Hi Tina,

This one stumped me for awhile too. I've attached a couple of pages from "Foundation Engineering" by Peck which might help you. These pages are from chapter 24 - "Footings Subjected to Moment." The resultant in this problem is outside the middle third of the footing, so section 24.3 applies in this case.

gipper

 

[user 788]

Thanks. That sure helps.