Need a book? Engineering books recommendations...
Return to index: [Subject] [Thread] [Date] [Author]
RE: Soil Pressure
[Subject Prev][Subject Next][Thread Prev][Thread Next]- To: <seaint(--nospam--at)seaint.org>
- Subject: RE: Soil Pressure
- From: "Alex C. Nacionales" <anacio(--nospam--at)skyinet.net>
- Date: Wed, 27 Jan 1999 14:23:52 +0800
The correct pressure should be p=1/2x(35)x(8)^2=1120 plf. Maybe you just mistyped it. I have my own question. Regarding the seismic pressure, What is the engineering basis for the upside down triangle pressure distribution. A rectangular distribution would be safer applied at 1/2 the wall height. Assumming soil weight is 150 pcf and g=.40 you get 20 pcf of siesmic load due to the earth. Alex C. Nacionales > -----Original Message----- > From: EphHirsch(--nospam--at)aol.com [mailto:EphHirsch(--nospam--at)aol.com] > Sent: Wednesday, January 27, 1999 9:44 AM > To: seaint(--nospam--at)seaint.org > Subject: Re: Soil Pressure > > > Sorry, last post contained nothing (I hit the wrong key before > anything was > typed). Based on the data your geotech gave you, the equivalent > pressure at > the base of the wall (assuming 8 ft. ht. as you stated) due to 35 pcf > equivalent fluid pressure is 8 x 35 = 280 psf with a triangular > distribution > diminishing to zero at the top and therefore an overall > horizontal total force > = 1/2 x 280 x 8 = 1,140 plf (i.e. pounds per horizontal linear > foot of wall). > How did you arrive at 75 psf for an answer?? How this force is > resisted and > what the reaction/shear /moment distribution is of course a function of > whether or not the wall is a cantilered one from its base or > restrained its > top by the floor framing system. Strictly speaking of course > this would also > affect the soil pressure distribution itself, but the geotech > presumably just > assumed triangular distribution in either case, based on how the > data appears > to be stated. > > Now, in addition to the above there will be added horizontal > pressure of 15H > (psf), where H is height of surcharge, NOT wall, with a total > horizontal force > of 8 x 15H (plf). Since you didn't give the surcharge height, > the numerical > values are not obtainable. > > The inverted triangular earthquake equivalent fluid pressure of > 20 pcf will > not increase the horizontal pressure at the base of the wall, but > will impose > an additional total horizontal force of 1/2 x 8^2 @ 20 pcf = 640 > plf applied @ > 2/3 the wall height. > > Does that answer your question? > > >
- References:
- Re: Soil Pressure
- From: EphHirsch
- Re: Soil Pressure
- Prev by Subject: Re: Soil Pressure
- Next by Subject: RE: Soil Pressure
- Previous by thread: Re: Soil Pressure
- Next by thread: RE: Soil Pressure
- About this archive
- Messages sorted by: [Subject][Thread][Author][Date]