Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Retaining Wall Question

[Subject Prev][Subject Next][Thread Prev][Thread Next]
>Another problem is that you may be using retaining wall software that does
>not include the vertical component of the active earth pressure.
>Conservatively, this vertical component would be equal to 1/3 of the
>horizontal component located at the heel of the footing. Without this,
>retaining wall footings become rediculously large. Check your input/output
>and software algorithms.
>Bill Allen

You have brought up something that I have wondered about.  When designing 
for a sloped backfill, do you include the vertical component for friction 
and for overturning (less conservative)?  From the references I have read, 
there seems to be some disagreement on this point.  (ie: Amrhein recommends 
excluding the force from the friction calc.  Other texts recommend 
excluding it from overturning).  You are right in saying that this force 
greatly affects the size of the footing.  The vert. component tends to (in 
many cases) move the pressure resultant TOWARD the kern.  By the way, I 
have used Retain Pro 4.0 and it seems to include the vert component in both 
cases.  Comment would be appreciated.

Kevin McCune