September 30, 2016
Expertise and new technology keep bridge safety-inspection efforts cutting-edge
Fifty-eight thousand of the 600,000 operational bridges in the United States are considered “structurally deficient” and in need of repair. With safety inspections required every two years, and more frequently for poor-condition bridges, more than 300,000 bridge safety inspections must take place every year.
Michael Baker International has been at the forefront of bridge safety inspection efforts for 45 years and literally wrote the book on what it takes to prepare the “army” of well-trained and equipped bridge engineers needed to properly inspect and keep our country’s bridges safe.
Setting the Standards
Inspector in a UBI inspecting the Baldwin Bridge - I-95 in Old Saybrook, Conn.
When the Federal Highway Administration (FHWA) published the National Bridge Inspection Standards
(NBIS) to set national requirements for the inspection of highway bridges in 1971, it also developed an accompanying manual called the Bridge Inspector’s Training Manual 70
. Twenty years later, Michael Baker was contracted to author the revised Bridge Inspector’s Training Manual 90,
and then updated it to today’s popular Bridge Inspector’s Reference Manual
). The BIRM
details programs, procedures and techniques for inspecting and evaluating a variety of in-service highway bridges. It remains the definitive resource used by bridge-inspection engineers in the U.S. today.
Michael Baker also has been providing classroom content for the FHWA’s training arm, the National Highway Institute (NHI), in the form of a bridge safety inspection course called “Safety Inspection of In-Service Bridges,” and teaching the course continuously since 1989. Since this or a similar course is required training for all bridge inspectors and essential for transportation agency employees, consultants and others involved in bridge inspection or bridge inspection management, it is safe to say that most of the key staff responsible for the safety inspection of our nation’s bridges have been trained by Michael Baker.
The two-week course incorporates two days of field trips so participants gain actual experience recognizing and documenting bridge deficiencies in decks, superstructures, substructures, and waterways. The field trips pose their own unique challenges, when severe weather or other extenuating circumstances including safety concerns, time, cost, and transportation coordination, make it impossible for a physical visit.
Another view from the UBI during the Baldwin Bridge inspection
Recognizing the need for an alternative delivery option if the physical bridge site visit is not possible, the FHWA contracted with bridge engineers at Michael Baker and technical developers at Engility Corporation to develop an interactive, virtual-reality, 3D, bridge inspection computer program that brings bridge inspection field work back to the safety of the classroom. Since its pilot in 2012, the award-winning, 3D-Virtual Bridge Inspection (VBI) has become the primary training tool for the safety inspection of in-service bridges and tunnels.
Every five years, Michael Baker re-competes for the privilege to continue to update and deliver the two-week long training, which has been taught in 45 states and also in Taiwan, Saudi Arabia, Kuwait and Canada.
Since it can be difficult for engineers to leave the office for two weeks to attend the course and to maximize bridge safety by certifying more bridge inspectors, the FHWA made the decision to condense the class to one week long and offer it only to professional engineers under the title, NHI Course 130056, Safety Inspection of In-Service Bridges for Professional Engineers. Michael Baker’s long-term dedication and expertise in bridge safety inspections, combined with its history of exemplary work with the FHWA, helped the firm competitively earn the contract to pilot and deliver the new course starting in 2016. It incorporates the 3D-virtual technology Michael Baker developed for the two-week course as well as other innovations, including an audience response system that gives participants the opportunity to use a remote-control clicker to engage and respond in class using technology provided.
Michael Baker engineers have developed or are currently developing nine different bridge and tunnel inspection courses for the NHI and have presented more than 800 courses. To date, the firm has trained more than 30,000 bridge inspectors nationwide.
A Legacy of Excellence and Innovation
SPRAT climbers inspecting the Irvin Cobb Bridge over the Ohio River in Paducah, Ky.
Michael Baker’s legacy of excellence in bridge safety inspections extends beyond the classroom. The firm’s 100 bridge safety inspectors/instructors are practicing bridge engineers with years of hands-on inspection experience. They continually upgrade their skills with ongoing safety and technical training at various levels and intervals, depending on their roles.
As part of the bridge inspection process, inspectors assess, evaluate and report on the condition of the structure and safety of the bridge from the foundation to the roadway, including the curbs, lighting and even signage. “Inspecting thousands of bridges annually for 30 bridge owners in 20 states, we are constantly on the lookout for ways to inspect safer, better and more cost-effectively,” said Paul McGuinness, Michael Baker’s Bridge Inspection Practice Lead. “This also allows Michael Baker to provide best-practices, incorporate new technologies and employ innovative solutions in the way We Make a Difference for our clients.”
Recently, Michael Baker added the use of unmanned aerial vehicles (UAS) in bridge safety inspections to its “innovation tool bag” to provide clients with the highest-quality inspections possible. Michael Baker has performed several structural inspections with UAS technology and currently has a contract to perform pilot inspections of state DOT bridges utilizing this technology.
Planning and preparation before the inspection includes reviewing the bridge plans and previous inspection findings, and identifying equipment and tools needed. The actual inspection consists of visual observations, a physical inspection, and when required, an advanced inspection with testing, depending on variables like the type of inspection being performed, construction type of the bridge and deficiencies found. Sketches, forms, tables and photographs document the findings in an inspection report. Any critical findings that pose a safety risk are immediately identified and reported so they can be addressed.
“More certified bridge safety inspectors ultimately mean safer bridges, roadways and waterways,” says McGuinness. “Michael Baker is proud to continue its legacy of excellence innovating and advancing bridge inspection science, technology and training to better preserve and ensure the safety of our national infrastructure.”
Header Image: Inspectors using a bucket boat lift to inspect the Leonard P. Zakim cable-stayed bridge in Boston, Mass