This Small Grant for Exploratory Research (SGER) is to conduct an immediate reconnaissance of the collapsed freeway and to document damaged and collapsed structural components and connections as well as to collect any other perishable data which can include fire-damaged steel and concrete, bolts and other connectors, drawings of original structure and seismic retrofit done in 1990s, material test results, reconstruction plans, videos, photos and other evidence of fire and damage collected by others as well as interviews with eyewitnesses to the fire and the collapse. At 3:42 am on the morning of Sunday, April 29, 2007, a tanker truck overturned on the elevated freeway connectors and started a fire that resulted in the collapse of two spans of the Distribution Structure, also known as the Mac Arthur Maze, twenty minutes later at 4:02 am. The understanding of response of elevated freeways to fire is very limited. The collapse of Mac Arthur Maze connectors provides the research community with a unique opportunity to learn from this collapse as much as possible, before the damaged structure is removed and replaced, in order to develop construction technologies and design concepts that can help transportation agencies, both state and federal, in designing and constructing steel overpasses that can survive such fire. As the aftermath of this event indicated, the collapse of such seemingly minor spans, with only 84 feet span, resulted in major transportation slow down and much discomfort and lost time for hundreds of thousands of commuters.
The information generated in this project for protection of steel elevated freeways against fire, can have broader applications to other elements of infrastructure such as ports, parking structures and major steel bridges throughout the country since fire caused by the trucks can result in collapse of steel bridges in all 50 states. Another broader implication is what can be learned from this accidental fire , can be useful in protecting the steel bridges in our infra-structure against intentional fires set by criminals to harm civilians and the economic as well as transportation infra-structure.
