UHPC – Innovations in Practical Applications (ACI Spring 2021 Convention, Virtual Sessions) As a consequence of material degradation, increasing traffic loads and seismic actions, a large number of existing reinforced concrete bridges are no longer safe and may represent a risk for human lives and for the robustness of the road network. Many of these bridges cannot be easily replaced given the cost of demolition and rebuilding in addition to the social costs for traffic interruption. As an alternative to replacement of the entire structure, service life of a bridge can be extended by adopting reliable strengthening techniques. Among these, High Performance Fiber Reinforced Concrete (HPFRC) jacketing was experimentally investigated in this research work. The pier was subjected to cyclic horizontal loads, both before and after strengthening, up to failure. Experimental results show that the HPFRC jacketing remarkably increased the flexural capacity of the pier, maintaining a significant post-peak residual strength. The jacketing also enhanced the structural response in terms of crack control and ultimate deformation.

Unlocking Workability Issues of UHPC (ACI Spring 2021 Convention, Virtual Sessions) Research currently being conducted at Oklahoma State University will be discussed to better understand the performance of UHPC with a focus on workability. Results from a wide range of tests such as rheology, compressive strength, modulus of elasticity, flexural strength, permeability, shrinkage, and durability, will be presented. The effects of mixture proportions on the UHPC performance, especially the rheological behavior, will be highlighted.