In this quarterly ABC-UTC Research Seminar, Royce W. Floyd, P.E., S.E., Ph.D., Principal Investigator; and Zachary Tiry, M.S. Student, present work under the ABC-UTC research project entitled Design Guidance for UHPC Connections of Precast Girders Made Continuous for Live Load [ABC-UTC-2016-C4-OU01], conducted at the University of Oklahoma.

Documents:
Design Guidance for UHPC Connections of Precast Girders Made Continuous for Live Load - pdf of presentation
Q&A Session - pdf

 Description: Connection of precast, prestressed concrete bridge girders to make spans continuous for live load allows for construction of bridges using precast elements while also allowing for structural benefits of live load continuity and durability benefits of reducing the number of bridge deck joints. Ultra-high performance concrete (UHPC) has mechanical and durability properties which far exceed those of conventional concrete and is, therefore, well-suited for continuity connections. While design of conventional concrete continuity joints is well known and frequently used in practice for new construction, little guidance exists on design of these connections using UHPC. The project described in this seminar extended previous research on structural behavior of UHPC continuity connections to produce design guidance using information from the literature and laboratory testing.

[Note: The previous research on structural behavior of UHPC continuity connections is titled “Evaluation of Ultra-High Performance Concrete, Fiber Reinforced Self-​Consolidating Concrete, and MALP Concrete for Prestressed Girder Repair,” sponsored by the Oklahoma Department of Transportation, SPR Item Number 2284, https://shareok.org/handle/11244/330981]

Presenters:

Presentation Graphics:

Figure 1. Joint reinforcement for hooked strand (a) and straight strand (b) designs

Figure 2. Typical continuity connection specimen failure when loaded in negative moment

Figure 3. Load-deflection curves for hooked and straight strand specimens tested for positive moment