Iowa Department of Transportation
Iowa Highway Research Board
Brent Pharesbphares@iastate.edu email >
Bridge Research Engineer, BEC
Yaohua "Jimmy" Deng
About the research
Accelerated bridge construction (ABC) has grown significantly in the last decade as an efficient method to rebuild bridges in the highway network. This method uses modern approaches in design, construction, and materials to reduce disruptions to traffic due to bridge construction.
In some cases, it is required to construct a new substructure beneath/within an existing bridge. There are various approaches to construct new foundations during ABC projects. The methods include spread footings, driven piles, drilled shafts, continuous flight augurs, and micropiles. Each method has its own advantages and disadvantages, which should be assessed for each ABC project.
For this research, each foundation method was reviewed by considering the specific features of the method that can be favorable to implement. To investigate new probable foundation construction approaches, a survey was distributed to state departments of transportation (DOTs). The survey included questions about the common bridge foundation approaches. According to the results, micropiles are the most commonly used piling approach, and there is no new method experienced by DOTs to establish foundations during ABC projects.