Nebraska LTAP
Date of this Version
3-2023
Document Type
Article
Citation
Morcous, G. and Taros, M. (2023). UHPC Decked I-Beam for Accelerated Bridge Construction. NDOT Research Report 21-005.
Abstract
Ultra-High-Performance Concrete (UHPC) is an excellent material for bridge construction due to its exceptional durability and superior mechanical properties. Several Departments of Transportations (DOTs), including NDOT, have limited the use of UHPC in bridge construction to joints and connections between bridge components due to the relatively high materials cost of commercially UHPC products. Recently, NDOT has sponsored a research project to develop a non-proprietary UHPC using local materials to reduce materials cost and ensure its availability to local contractors and precast producers. The project was completed successfully and an economical UHPC mix that satisfied all workability, durability, and strength requirements was developed and tested. Therefore, it is economically feasible to expand the use of UHPC to bridge superstructure components that can have a service life of over 150 years.
The objective of this project is to develop a UHPC superstructure system for bridges in Nebraska that is optimized with respect to structural efficiency, constructability, and economy. Several UHPC superstructure systems used in France, Korea, Malaysia, USA, and Canada including pi-girders, bulb-tee girders, tub girders, box girders, decked I-beams, and waffle slabs, were reviewed and evaluated to determine the system(s) that meet NDOT needs. A decked I-beam (DIB) section was selected due to its ease of production, constructability, and structural efficiency. Formwork design, production trials, and material/structural testing were conducted for UHPC DIB specimens with ribbed and solid slabs using pre-tensioning and post-tensioning systems. Design examples of a typical bridge using DIBs were also presented to demonstrate the implementation of the latest UHPC design specifications/guidelines.