AREA SURCHARGE AND EFP
AREA SURCHARGE AND EFP
(OP)
Using EFP, for an area surcharge load (i.e., a load of infinite length and width) behind a retaining wall, wouldn't the magnitude of the force be S x H (where S is the surcharge load in psf and H the wall height in ft)? Wouldn't the magnitude of the loading diagram be S? And thus the moment be (S x H^2)/2?
Thanks in advance.
Thanks in advance.





RE: AREA SURCHARGE AND EFP
k can be active or at rest pressure (usually passive is not used in retaining wall design)
The retaining wall will also see lateral load from the soil and groundwater which will need to be added to the surcharge load.
RE: AREA SURCHARGE AND EFP
RE: AREA SURCHARGE AND EFP
Note that if the surcharge area is large enough, this may be a good approximation. However if the surcharge area is localized, the shape will be parabolic.
RE: AREA SURCHARGE AND EFP
RE: AREA SURCHARGE AND EFP
Maybe it wasn't such a good question. But as "yack" pointed out, most soils reports that I have read provide EFP values for designing retaining walls (of course, at the back of these reports there are shear strength tests which provide phi, which can be used for Rankine, etc.). Therefore, if one is trying to determine the moment from an area surcharge (infinite length and width) using an EFP approach, what is the load diagram (and thus the moment) behind the wall.
RE: AREA SURCHARGE AND EFP
Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora. See FAQ158-922 for recommendations regarding the question, "How Do You Evaluate Fill Settlement Beneath Structures?"