Northeast Extreme Tee (NEXT) Beam with Rochester VT Case Study

February 15, 2018 1:00 pm

Rita Seraderian, P.E., Executive Director, Precast/Prestressed Concrete Institute Northeast; Rob Young, P.E., Senior Project Manager, Structures Section, Vermont Agency of Transportation; Joe Carrara, President, J.P. Carrara & Sons, Inc.; and Q&A Panel member Mike Culmo, P.E., Vice President of Transportation and Structures, CME Associates, Inc.

Webinar Documents:
Background and Overview, Rita Seraderian - pdf of presentation
Rochester VT Bridge 15 over Brandon Brook, Rob Young - pdf of presentation
Precast Abutment and NEXT Beam Fabrication, Joe Carrara - pdf of presentation
Q&A Session - pdf
News - February 15, 2018 - pdf of presentation

Description: The precast concrete Northeast Extreme Tee (NEXT) beam was developed in 2008 by the PCI Northeast Bridge Technical Committee, which is made up of DOTs, engineers, and industry representatives. This unique beam element offers significant advantages over typical stringer-beam bridges. The top flange of the beam can be designed as the deck or designed to support the weight of a cast-in-place concrete deck. The beam can be readily fabricated, transported, and erected. This presentation will include the background, development and applications for the NEXT beam. Also included will be a case study of Route 73 Rochester Vermont Bridges 15 & 16. For this 2014 project the Vermont Agency of Transportation (VTrans) conducted an engineering study, which recommended the use of the NEXT beam. Vtrans also set a road-closure maximum time of 60 hours for Bridge 16 and 84 hours for Bridge 15. Project background, owner’s perspective, and design and construction details will be discussed. Also discussed will be the fabrication process and challenges, in addition to overall lessons learned.

Presentation Photos/Graphics:

1) 2010 - York, Maine - first NEXT Beam bridge

2) Fabrication of a NEXT beam with variable flange thickness and dual-coated Z-bar reinforcement

3) Rochester VT NEXT Beam with precast backwall and parapet

4) Shipping of precast abutment component

5) Erection of NEXT beam utilizing a slider beam; with front of beam still on dolly, tractor pushes NEXT beam across the river to the crane on the other side

6) Erection of NEXT beams utilizing two cranes and off-set picking beams

7) NEXT Beams in place; closure pour forming

8) 2014 Rochester VT Bridge complete