This design memorandum is an amendment to AASHTO Guide Specifications for LRFD Seismic Bridge Design and revisions approved in 2008 by the AASHTO Highway Subcommittee on Bridges and Structures. Revisions include 2008 Ballot Items 74, 75 and 76. WSDOT requires all new bridges, bridge widenings, and retaining walls to be designed in accordance with the requirements of the AASHTO Guide Specifications, revisions and WSDOT amendments.

The AASHTO Guide Specifications for LRFD Seismic Bridge Design and Ballot Items could be downloaded from the following web sites:

The following items summarize WSDOT’s additional requirements and deviations from the AASHTO Guide Specifications for LRFD Seismic Bridge Design:

Background

This design memorandum describes WSDOT’s amendments to AASHTO Guide Specifications for LRFD Seismic Bridge Design and revisions approved in 2008 by the AASHTO Highway Subcommittee on Bridges and Structures based on the WSDOT design and construction requirements. This memorandum supersedes design memorandum issued on February 18, 2008.

If you have any questions regarding these issues, please contact Bijan Khaleghi at 705-7181 or Chyuan-Shen Lee at 705-7441.

cc:   Mohammad Sheikhizadeh, Bridge Construction - 47354

Click here for a PDF of this design memo.

Click here for a PDF of Figure 3.3-1a.

Click here for a PDF of Figure 3.3-1b.

Click here for a PDF of Figure 3.3-2.

Click here for a PDF of Figure 3.3-3.

Click here for a PDF of Figure 4.11.2-1.