Bridge Design Manual LRFD

Publication Version
M 23-50.22
Manual Manager
Michael Rosa,
Bridge and Structures Office, Engineering and Regional Operations Division

This manual has been prepared to provide Washington State Department of Transportation (WSDOT) bridge design engineers with a guide to the design criteria, analysis methods, and detailing procedures for the preparation of highway bridge and structure construction plans, specifications, and estimates.

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Bridge Design Manual Memorandums 

Bridge design memorandums are issued as interim updates to the Bridge Design Manual. 

Active design memorandums supersede the contents of the Bridge Design Manual and are currently in force. View Active Bridge Design Manual memorandums

Inactive memorandums provide historical context and background on design policies incorporated into the Bridge Design Manual. View Inactive Bridge Design Manual memorandums.

Individual Chapters

Contents (PDF 278KB)
Foreword (PDF 96KB)

Chapter 1 General Information (PDF 1.0MB)
Chapter 2 Preliminary Design (PDF 3.6MB)
Chapter 3 Loads (PDF 906KB)
Chapter 4 Seismic Design and Retrofit (PDF 4.7MB)
Chapter 5 Concrete Structures (PDF 18.2MB)
Chapter 6 Structural Steel (PDF 2.2MB)
Chapter 7 Substructure Design (PDF 2.4MB)
Chapter 8 Walls and Buried Structures (PDF 3.0MB)
Chapter 9 Bearings and Expansion Joints (PDF 1.5MB)
Chapter 10 Sign, Barriers, Approach Slabs, and Utilities (PDF 8.6MB)
Chapter 11 Detailing Practice (PDF 1.4MB)
Chapter 12 Quantities, Costs, and Specifications (PDF 2.5MB)
Chapter 13 Bridge Load Rating (PDF 1.9MB)
Chapter 14 Accelerated and Innovative Bridge Construction (PDF 2.5MB)
Chapter 15 Structural Design Requirements for Design-Build Contracts (PDF 1.5MB)

Revision History

M 23-50.22

M 23-50.21

M 23-50.20

 M 23-50.19 

M 23-50.18 

M 23-50.17  

M 23-50.16 

M 23-50.15 

M 23-50.14

M 23-50.13 

M 23-50.12

M 23-50.11

M 23-50.10

M 23-50.09 

M 23-50.08

M 23-50.07 

M 23-50.06 

M 23-50.05 

M 23-50.04 

M 23-50.03 

M 23-50.02 

M 23-50.01 February 2007

November 2006

September 2006

August 2006

July 2005

April 2005

August 2002

Slow down – lives are on the line. 

In 2023, speeding continued to be a top reason for work zone crashes.

Even one life lost is too many.

Fatal work zone crashes doubled in 2023 - Washington had 10 fatal work zone crashes on state roads.

It's in EVERYONE’S best interest.

95% of people hurt in work zones are drivers, their passengers or passing pedestrians, not just our road crews.