Events in July 2023
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Prioritization Efforts for ABC in Texas Prioritization Efforts for ABC in Texas
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July 20, 2023Graham Bettis, P.E., State Bridge Engineer and Director of Bridge Division, Texas Department of Transportation; and Bernie Carrasco, P.E., Bridge Management Section Director, Bridge Division, TxDOT
Webinar Documents:
Prioritization Efforts for ABC in Texas - pdf of presentation
- Link: TxDOT's Bridge Standards
- Link: TxDOT's Departmental Materials Specifications 7300, Precast Concrete Fabrication Plants
Q&A Session - pdf
News - July 20, 2023 - pdf of presentationDescription: The Texas Department of Transportation (TxDOT) has utilized various accelerated bridge construction (ABC) techniques to deliver projects quickly and minimize disruptions to traffic. Each year, TxDOT replaces between 120 and 150 bridges through the bridge replacement program and adds an additional 300-400 bridges to the inventory. These projects provide ample opportunity for the use of a variety of ABC techniques. This presentation covers TxDOT resources available to encourage the use of accelerated bridge construction, including standard drawings, as well as the proposed changes to project planning to promote the use of ABC more often.
Presenters:
Graham Bettis, P.E.
State Bridge Engineer
Director, Bridge Division,
Texas Department of Transportation
Email: Graham.Bettis@txdot.govGraham is the Texas State Bridge Engineer, and he has been in this position since the summer of 2018. In this role Graham helps to oversee the design, construction, inspection, and maintenance of the statewide inventory of 55,000 bridges. His background is primarily in structural evaluation and preservation. Graham graduated from the University of Texas at Austin in 1999 and worked as consultant in the forensic engineering field before moving to TxDOT’s Materials and Tests Division in 2006 and then to Bridge Division in 2011.
Bernie Carrasco, P.E.
Bridge Management Section Director,
Bridge Division,
Texas Department of Transportation
Email: Bernie.Carrasco@txdot.govBernie has worked in the TxDOT Bridge Division since 2002 after graduating from Texas A&M. He became the Bridge Management Section Director in 2018. Bernie’s career at TxDOT has included bridge and tunnel inspections, bridge design, and now overseeing the programming of rehabilitation and replacement bridge projects through TxDOT’s Category 6 Funds as well as maintenance of the bridge inspection data.
Presentation Photos/Graphics:
1) Precast Concrete Bent Cap Option (standard drawing and precast cap being installed)
2) Use of the NEXT 36D Beam in TxDOT Amarillo District
3) Use of Pre-topped Tx-Girders in TxDOT Bryan District
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ASBI Monthly Webinar: I-59/20 Birmingham Viaduct Project -
Design Guidance for UHPC Connections of Precast Girders Made Continuous for Live Load Design Guidance for UHPC Connections of Precast Girders Made Continuous for Live Load
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July 28, 2023In 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 - pdfDescription: 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:
Royce Floyd, Ph.D., P.E., S.E.
Associate Professor
School of Civil Engineering and Environmental Science
The University of Oklahoma
Email: rfloyd@ou.eduZachary Tiry
(M.S., May 2023, OU)
Graduate Structural Engineer
Halff Associates, Inc.
Richardson, Texas
Former Graduate Research Assistant
The University of Oklahoma
Email: zacharytiry@ou.eduPresentation 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