Lessons Learned from Bridge Construction Failures

Approximately 3,500 State or Federal-aid highway bridges are built in the United States every year. The majority of these bridges are built without incident, which is a credit to the construction industry. However, in the past 30 years, several major bridge failures occurred during construction and were attributed to construction practices and procedures. Statistically, bridge falsework represents over one-third of the total recorded falsework collapses, and most of these occur during construction of conventionally reinforced concrete beam or box-girder bridges. This paper examines failures that occurred during construction of the Arroyo Seco Bridge in Pasadena, California; the Cline Avenue Ramp in East Chicago, Indiana; the I-75 Bridge near Zilwaukee, Michigan; the Sunshine Skyway in Tampa Bay, Florida; and the Lake Street/Marshall Avenue Bridge in Minneapolis, Minnesota. Primary and contributing causes of these failures are identified. From a forensic perspective, errors that contribute to falsework failures are almost always obvious after the fact, generally result from human error, and could have been avoided. A clear need exists to adopt unified design criteria and standards for the temporary structures used to construct highway bridge structures, addressing both the technical and procedural requirements of temporary construction.