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Memorandum

TO: All Design Section Staff
FROM: J. Kapur
DATE: September 17, 2002
SUBJECT: LRFD General Notes – Pile Foundation

The recent communications with the WSDOT Geotechnical Branch have resulted in simplification in the LRFD General Notes, and establishing the following procedure in pile foundation:

Only pile ultimate bearing capacity shall be included in the General Notes. The ultimate pile bearing capacity shall be taken as the maximum pile loading from the applicable service, strength and extreme-event limit states. A separate table showing all pile loadings, tips elevation, and pile layout data shall also be furnished to the project Geotechnical engineer prior to the completion of the project.

Background:

The current practice is to show all LRFD pile foundation loadings from service, strength and extreme-event limit states in the general notes. Showing all these loadings is confusing since the pile ultimate bearing capacity is the only loading required for pile driving.

In order to simplify this process, the Geotechnical Branch recommends showing only pile ultimate bearing capacity in the general notes. However, designers are required to submit the pile foundation data sheet to the Geotechnical engineer for their review as soon as foundation design is completed. A copy of the revised General Notes and Pile foundation data sheet is attached, and could be found in J:\PSConcrete subdirectory.

If you have any questions regarding these issues, please contact Bijan Khaleghi at

705-7181.

JK:dsb

MWA/BK

Attachment 1
Attachment 2

cc: J. A. Weigel, Bridge and Structures - 47340

F. Higgins, Bridge and Structures - 47340