AASHTO Domestic Scan Proposal Form
AASHTO is soliciting topic proposals for a US Domestic Scan Program, loosely modeled after the
existing FHWA/AASHTO/NCHRP International Technology Scanning Program. Each selected
scan topic will be investigated through site visits to three to six locations over a one or two week
period, conducted by a group of eight to 12 transportation professionals with expertise in the
selected topic area. Proposed topics should meet the following criteria:
 Address an important and timely need for information by transportation agencies;
 Are of interest to a broad national spectrum of people and agencies;
 Are complex and also “hands-on,” meaning they lend themselves particularly well to
exploration through on-site visits; and
 Are sufficiently focused that the tour participants are able to investigate and understand
key issues in the limited time available on the tour.
Proposals should be returned to kplatte@aashto.org no later than August 26, 2005.
Proposal Contact Information
Name: Thomas Saad, P.E.
Title: FHWA, Structural Design Engineer
Address: 19900 Governors Drive, Olympia Fields, IL 60461
E-mail: Thomas.saad@fhwa.dot.gov
Telephone number: 708.283.3521
Date of submission: November 10, 2008
Title of Proposed Scan
Best Practices for Providing Bridge Safety and Serviceability in Bridge Design, Load Rating and
Posting
Problem Statement
(What topic is to be examined? What drives the need for the scan? Why now?)
The AASHTO SCOBS has recently completed the development of a comprehensive set of
reliability based design and load rating codes to enhance the safety and serviceability of bridges
and other highway structures in design and load evaluation. Several lead States have been
operationally implementing Load and Resistance Factor Design for many years. Only a few
States are implementing Load and Resistance Factor Rating practices. There are a large number
of States that are currently in the process of fully implementing both LRFD and LRFR at the State
and local level and are trying to adjust operational procedures to implement the complimentary
set of provisions and maximize the bridge safety benefits that can be achieved. A great deal of
information for operationally mainstreaming the code provisions into routine practice is available
from lead States, but this information has not been collected and organized to share with other
State Bridge Design, Maintenance and Load Permitting offices. There is no set of documented
‘best-practices’ for designing, rating and permitting our nation’s highway bridges.
This scan will define the best practices for operationally implementing the AASHTO LRFD
Bridge Design Specifications in conjunction with the AASHTO Manual for Bridge Evaluation
(LRFR Standards) to obtain the full benefits of the new reliability based specifications. A final
report would provide a set of the best operational practices for States to deploy the codes and to
increase bridge safety and serviceability.
Scan Scope
(What specific subject areas are to be examined? Which cities and states might be visited?
Which agencies/organizations (including specific departments or types of staff if applicable)?
The scan team would conduct extensive reviews of lead State bridge design, load rating and load
permitting for both State and locally-owned bridges. The scan team would capture State Bridge
Program goals for maintaining high levels of safety and serviceability in the State’s bridge
network and identify the best State-specific design and load rating practices for achieving those
goals. State-specific guidelines for implementing the LRFD and LRFR provisions would be
collected State program and the best practices from these States would be documented and
disseminated.
Some States that have extensive program guidelines and experience for implementing LRFD
include Florida, Delaware, Washington, New York, Pennsylvania and Tennessee. These States
likely have some disparate bridge program goals and traffic demands that are reflective of the
varying demands and needs of States across the country. Lead States that have examined and are
making efforts to implement LRFR for both load rating and load permitting include the States of
Oregon, New York, Louisiana, Florida, and Delaware.
Several of these States have local agencies responsible for designing, load rating and permitting
bridges. A representative number of local agencies should be interviewed to determine how
State Highway Agencies (SHA) establish bridge program policies that allow local agencies an
opportunity to integrate their bridge design and operational safety program objectives with those
of the SHAs.
Scan Objectives
(What key information is to be gained? What information is to be shared after the
scan? Who would the audience be for this information?)
The key information to be collected includes State-specific policies and operational guidelines for
designing new bridges for safety and serviceability over the design life of the structure. Practices
for evaluating and rehabilitating existing bridges would also be collected.
State and local agency policies and practices for load rating bridges, posting substandard bridges
and permitting overweight vehicles would also be collected and evaluated.
The scan would attempt to quantify the various safety and performance benefits that are
expected to be achieved through the implement of the LRFD and LRFR provisions and establish
the best practices for operationally transitioning State-specific practices to maximize the bridge
safety and serviceability. This information would be of great benefit to share with States
currently developing protocol for implementing the complete set of reliability based design tools.
Benefits Expected (Including potential impacts on current technology or procedures)
State-specific guidance and practices identified that increase the safety and durability of bridges.
Rapid deployment of the full set of AASHTO’s reliability based design and evaluation standards
to increase bridge design safety and serviceability.
Improved practices for evaluating existing bridges subject to increasing traffic loads.
Improved practices for posting bridges that cannot safely accommodate State legal loads.
Provide State Highway Agencies with solutions for operationally implementing the AASHTO
LRFD and LRFR codes.
Protocol for implementing new reliability based design and analysis methods to maximize bridge
safety benefits.
Improved operational handling of the growing number of annual and oversize load permits.
Identifying needs of State agencies to improve bridge safety and performance that will result in
priority research needs statements to improve the new codes.