Retaining Rock
Retaining Rock
(OP)
What's the most commonly used friction angle when designing a retaining wall that will retain rock fill or riprap?
Are you an
Engineering professional?
Join Eng-Tips Forums!
Engineering professional?
Join Eng-Tips Forums!
- Talk With Other Members
- Be Notified Of Responses
To Your Posts - Keyword Search
- One-Click Access To Your
Favorite Forums - Automated Signatures
On Your Posts - Best Of All, It's Free!
- Students Click Here
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.
Talk To Other Members
RE: Retaining Rock
I think to remember AASHTO (or was other code?) limited the internal friction angle to 34 deg.
The friction factors that AASHTO table 5.5.5B gives for friction soil-concrete for sound rock, gravel etc range from about 30 to 35 deg, so it would imply somewhat higher angles of inner friction (except that friction at the interface is assumed go as high as the internal friction angle), but maybe not as high as at the 3/2 factor higher derivable from the NBE AE-88 limit for friction at the interface.
Real angles of internal friction should be in the 45 to 51 deg range for rough and dry broken sharp stones, I think to remember.
Refer to the applicable code if any.
RE: Retaining Rock
I was going to use 40 deg... Thanks!