ISU Research Projects
2nd-Cycle Projects (2016-grant)
- Synthesis of Available Contracting Methods: Accelerated bridge construction (ABC) is the solution of choice to upgrade substandard bridges, while maintaining traffic flow and optimizing safety through work zones. However, the perception of higher construction costs for ABC versus conventional construction continues in spite of numerous ABC projects having lower construction costs relative to conventional construction. This inaccurate perception and the fear of cost overruns are causing some bridge owners to be hesitant about using ABC technologies, especially those technologies related to bridge system moves which can provide the greatest benefit for safety and traffic flow impacts. While the traditional contracting method for state DOTs is primarily unit price contracting, there are alternatives, including cost plus, lump sum, lump sum with guaranteed maximum price, and progressive lump sum with a guaranteed maximum price. To date there has been little investigation into the use of these alternatives on ABC projects, this project will explore the use of these options to understand the state of practice and provide insights and lessons learned for DOTs.
- Performance of Existing ABC Projects – Inspection Case Studies: As the initial deployments of ABC methods age, it becomes necessary to inspect the structures for both maintenance decision making and for assurance of adequate service life performance. Current inspection methods used for traditional bridge structures can be modified to establish inspection protocols for ABC projects. Once inspection protocols have been developed, existing ABC projects can be inspected. After which, any apparent performance trends can be documented and best practices identified.
- Development of Non-Proprietary UHPC Mix: This project develops and characterizes economic, non-proprietary UHPC mixes made with materials locally available. This will be achieved through a holistic set of laboratory experiments that will be primarily focused on the choice of fibers, which are known as the costliest ingredient of UHPC mixes.
- Development of ABC Course Module: Design of Link Slabs: This project builds on the findings from a former ABC UTC-sponsored research project on link slabs and develops a short course module to provide the design guidelines and practical recommendations necessary to properly implement a link slab in jointless bridges.
1st-Cycle Projects (2016-grant)
3rd-Cycle Projects (2013-grant)
- Development of Guidelines to Establish Effective and Efficient Timelines and Incentives for ABC [ABC-UTC-2013-C3-ISU01]: The main objective of the proposed project is two folds: 1) Provide guidelines to evaluate the direct and indirect costs (traffic delays and opportunity losses) under following conditions: conventional construction, only ABC techniques, only incentivizing strategies, and combination of ABC and incentivizing strategies; and 2) Develop a decision-making framework to compare the total costs and durations of each of the candidate techniques to optimize for the lowest cost and construction duration techniques accordingly.
- Integral Abutment Details for ABC Projects, Phase II [ABC-UTC-2013-C3-ISU02]: The proposed research aims to develop ABC compatible integral abutment connections to marry the two technologies together and continue to advance the quality, performance, economics and constructability of bridges to meet the demands of today’s growing infrastructure.
- Inspection and QA/QC for ABC Projects [ABC-UTC-2013-C3-ISU03]: The objective of this research is to explore available nondestructive testing technology to determine applicability for the inspection and quality control of accelerated bridge construction components.
2nd-Cycle Projects (2013-grant)
1st-Cycle Projects (2013-grant)