Need a book? Engineering books recommendations...

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

RE: Drilled Pier/pile-Support is pinned or fixed

[Subject Prev][Subject Next][Thread Prev][Thread Next]

John,

Thanks a lot. I don’t have very high seismic forces. But very high wind loads. Here in Qatar, one pile/drilled pier per column is very common.

Regards

Ashraf

 


From: j.n.sigalas [mailto:sigalasi(--nospam--at)central.ntua.gr]
Sent: 30 August 2006 22:29
To: seaint(--nospam--at)seaint.org
Subject: Re: Drilled Pier/pile-Support is pinned or fixed

 

Ashraf,

In my oppinion a 100% pinned connection(if finally assumed in the design)should be very carefully detailed and materialised at the site.

In addition to the above, I again believe,that the performance of a pinned connection can not be practically guaranteed especially at locations

very difficult to inspect(and even more difficult to repair, should that be necessary).

I am sure that as your piles will pass thru a 3 to 5 mthick comressible layer your design addresses also the issues of

- negative skin friction(can cause signifficant increase of the axial load) and

- the small lateral support in the top 3 to 5 m(could be critical particularly in seismic regions where high horizontal forces are transmitted).

Of course, I don't know the particulars of your project however introducing pile caps,monolithic pile-to-pile cap connection and more than

one pile per column would be a worth considering alternative if the project was in my end (Greece).

regards

john n. sigalas

 

----- Original Message -----

Sent: Wednesday, August 30, 2006 8:43 AM

Subject: Drilled Pier/pile-Support is pinned or fixed

 

Hello All,

I am designing a pile/drilled pier foundation for a building. I want to reduce the support forces so that I can reduce the no. of piles/pier. The columns are almost 20m high. I would like to know whether I can take base as pinned in analysis if I am using singe piles/piers for each column. The pile/drilled piers are around 6 to 10 m deep. The piles/piers here are designed based on skin friction with a pile socket length in rock of 3 to 6m. The rock is of poor quality with RQD (Rock Quality Designation) 0% to 50%. These are from Geotechnical report. I would like to mention that the soil up to 3 to 5m from Pile/Pier head is mainly of hydraulic fill material. N value of top soil varies from 35 to 4. The site is in a reclamation area.

Thanks in advance,

Regards

Ashraf

*** WORLEYPARSONS GROUP NOTICE ***
"This email is confidential.  If you are not the intended recipient, you must not disclose  or  use the  information contained in it.  If you have received this email in error,  please notify us immediately by return email and delete the email and any attachments. Any personal views or opinions expressed by the writer may not necessarily reflect the views or opinions of any company in the WorleyParsons Group of Companies."
 
*** WORLEYPARSONS GROUP NOTICE ***
"This email is confidential.  If you are not the intended recipient, you must not disclose  or  use the  information contained in it.  If you have received this email in error,  please notify us immediately by return email and delete the email and any attachments. Any personal views or opinions expressed by the writer may not necessarily reflect the views or opinions of any company in the WorleyParsons Group of Companies."