Return to index: [Subject] [Thread] [Date] [Author]
Earthquake Forces and Design Deformation of a Pile Group
[Subject Prev][Subject Next][Thread Prev][Thread Next]- To: <seaint(--nospam--at)seaint.org>
- Subject: Earthquake Forces and Design Deformation of a Pile Group
- From: "Brian S Bossley" <BSBossley(--nospam--at)venturaengineering.com>
- Date: Tue, 5 Apr 2005 16:28:23 -0400
Ok - once again - another question for the structural giants of SEAINT: Correct me if I'm wrong, but under ASCE 7-98 or ASCE 7-02, the earthquake forces are ULTIMATE (yet elastic) forces and then these are factored down if you are using WORKING STRESS. But I seem to remember someone telling me (at an ASCE seminar, I believe) that the design deformation is the deformation that you get from your ULTIMATE combinations, regardless of which set of combinations you chose for design. I know that in ASCE 7, they have an equation delta(x) = Cd* delta(xe)/I for the calculation of the story drift determination, where Cd is the deflection amplification factor to get you from a ELASTIC deformation to a design INELASTIC deformation and delta(xe) is the ELASTIC deformation based on the shears you've calculated for the ULTIMATE earthquake forces. So I assume that the INELASTIC deformation (delta(x)) is what would actually occur when the big one hits - or at least for design considerations. Now I have pretty big lateral forces transferred to a pile group (HP's) and I am told by the geotech guy that the forces in each pile are not based on relative stiffness of the piles (weak axis vs strong axis), but rather on some fifth order interaction equation that I don't know anything about because I'm not a geotech. But, for a set of given deformations, he gave me the shears at the top of the pile for both weak axis and strong axis and also, the corresponding bending moments. Now, would the force transferred to these piles be based upon the base shear or upon the design deformation? If deformation, is that the inelastic ultimate deformation or the elastic ultimate deformation? Brian S. Bossley, PE Ventura Engineering 7610 Olentangy River Rd. Columbus, OH 43235 (614) 847-1110 x121 ******* ****** ******* ******** ******* ******* ******* *** * Read list FAQ at: http://www.seaint.org/list_FAQ.asp * * This email was sent to you via Structural Engineers * Association of Southern California (SEAOSC) server. To * subscribe (no fee) or UnSubscribe, please go to: * * http://www.seaint.org/sealist1.asp * * Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you * send to the list is public domain and may be re-posted * without your permission. Make sure you visit our web * site at: http://www.seaint.org ******* ****** ****** ****** ******* ****** ****** ********
- Prev by Subject: RE: E-Files and Clients....
- Next by Subject: Earthquakes and geotechs
- Previous by thread: RE: Building Implosion
- Next by thread: Richard Bradshaw, S.E.
- About this archive
- Messages sorted by: [Subject][Thread][Author][Date]