Kamal H Khayat, Mahdi Valipour
Missouri University of Science and Technology, Rolla, Department of Civil, Architectural and Environmental Engineering
Bridge decks; Concrete overlays; Overlays (Pavements); Pavement design; Pavement performance; Service life; Ultra high performance concrete; Bridges and other structures; Design; Highways; Materials
The main objective of this research was to develop a cost-effective ultra-high performance concrete (UHPC) for bonded bridge deck overlays. The high durability and mechanical properties of such repair material can offer shorter traffic closures and prolong the service life of the bridge deck. The UHPC was optimized using supplementary cementitious materials (SCMs), proper combinations of sands, and adequate selection of fiber types and contents. . Early-age and long-term deformation caused by concrete, humidity and temperature gradients, as well as cracking and delamination were monitored over time. Test results indicate that there was no surface cracking or delamination in UHPC overlays after more than 200 d of casting. After laboratory investigations, a life cycle cost analysis (LCCA) was determined for the selected concrete mixtures with different mixture compositions and performance characteristics. Results indicate that, based on both deterministic and probabilistic results, UHPC overlay with minimum 25 mm (1 in.) thickness is a more cost-effective option compared with other commonly used materials, such as latex-modified concrete and conventional bonded concrete overlays.