Spliced Precast Girders Solving Transportation and Handling Problems

Project Genesis Problem: Girder Weight and/or Length Haul weight limitations Haul size limitations Permitting costs and scheduling Terrain and access Precast limited to spans < 160’

Pennsylvania Permit Vehicles 33X95.5 PABT

Project Genesis Solution: Spliced Girder Design Segment girder into 2 or more pieces Pretension for handling Haul segments to jobsite Assemble segments using post-tensioning Erect girder as “pretensioned” girder

Drop-In Span Projects Fuller Warren Bridge, Jacksonville, Florida Moore Haven Bridge, Florida Highland View Bridge, Florida Main Street Viaduct, Pueblo, CO

FULLER WARREN BRIDGE, JACKSONVILLE, FL

MOORE HAVEN BRIDGE, FLORIDA

HIGHLAND VIEW BRIDGE, FL

MAIN STREET VIADUCT, PUEBLO, CO

MAIN STREET VIADUCT, PUEBLO, CO

Simple-Span Projects Harbour Island People Mover, Tampa, FL Klickitat County, WA Rock Cut Bridge, WA I-15 Reconstruction, Salt Lake City, UT

Klickitat County, WA Built 1954 90 ft total length 3 – 30 ft segments Erected on falsework Spliced because of contractor’s equipment

KLICKITAT COUNTY, WA

Harbour Island People Mover Built 1984 Single box beam elevated guideway 140 ft total length 2 – 70 ft segments Erected on falsework

HARBOUR ISLAND PEOPLE MOVER

HARBOUR ISLAND PEOPLE MOVER

HARBOUR ISLAND PEOPLE MOVER

HARBOUR ISLAND PEOPLE MOVER

HARBOUR ISLAND PEOPLE MOVER

Rock Cut Bridge, WA Built in 1995 190 ft total length 3 segments Spliced near site, then launched Access required splicing Owners wanted concrete bridge Very tight schedule and budget

ROCK CUT BRIDGE, WA

ROCK CUT BRIDGE, WA

ROCK CUT BRIDGE, WA

Project Objectives Extend current span limit Provide a concrete alternative for the 150’ – 225’ span range Provide pretensioned girder equivalency Utilize PennDOT detailing to degree possible No additional complexity for contractor

PA Spliced Girder Standards Based on PA Bulb Tee Single-span splicing 2- or 3-piece segmentation Span Limit: 225 ft

Project Scope Phase I: Concept design Phase II: Standard drawings & details Phase III: Design examples

Standard Drawings

Based on PA Bulb Tee

Single-Span Spliced Girder

End Block

End Block

Reinforcing

Reinforcing

Concepts & Design Issues Detailing issues Fabrication details Erection details Splice details Post-tensioning and grouting

Detailing Issues Girder geometry End blocks and anchorages Flange Bulb End blocks and anchorages Joints – Girder end treatments Post-tensioning ducts Rebar placement Bearings

Fabrication Issues Post-tensioning End blocks and anchorages Haunched pier segments More intensive fabrication effort

Erection Issues Splicing before erection In-place splicing Girder stability Crane pick

Erection Scheme

Erection Scheme

Splice Details Shear keys Rebar splicing Duct splicing Wet joints

Closure Pour

Post-Tensioning Issues Tendon size (7-0.6”, 12-0.6”, 19-0.6”) Duct size and type (plastic or metal) Anchorage type Anchorage zone reinforcement Anchorage protection Grouting

Prestressing Materials PT Strand Strength (ksi) 250/270/300

Types of Post-Tensioning Tendons

Plastic vs. Metal Ducts Metal Plastic More widely used Less costly Unlimited sizes Stiffer Better grout flow Plastic More durable Non-corrosive Lower coefficient of friction

Anchorage Types

Multistrand Anchorage Sizes Anchor head Trumpet Bearing plate Duct and coupler Permanent grout cap Inspectability The VSLAB+TM System was developed for use in slabs. If your project has beams, VSL will combine our ES multistrand grouted system for beams with our VSLAB+TM System for slabs. 0.5” Strand - 12,19,31,43,55 0.6” Strand - 7,12,19,22,31,37,55

Anchorage Zone Reinforcement

Corrosion Protection of Strand Corrugated plastic duct Galvanized corrugated metal duct Smooth HPDE duct The VSLAB+TM System was developed for use in slabs. If your project has beams, VSL will combine our CS multistrand grouted system for beams with our VSLAB+TM System for slabs.

Protection of Anchorages Non metallic permanent grout caps We see here the stress and components, both assembled and disassembled. Looking at the line of disassembled components from left to right we see the recess former, the grout cap, the end anchor head, the bearing plate, the 2 half shells, the wedge clamps and the duct. When assembled, the system is mechanically locked together, providing the strand with reliable encapsulation. . Galvanized Bearing plates Anchorheads Spiral reinforcement

Multistrand Stressing Equipment Stress 20% then 100% Elongation measured during stressing

PT Grouting Details Procedures QC Specifications Inspection

Practice Recommended by ASBI and PTI Specifications Grouting Materials Testing, Q/A, Q/C Construction VSL decided few years ago to carry out an extensive R & D program on grout to review the Grout Mix Design, Procedures, Equipment and Personnel on the impact of grout We will show you selected results of the R&D program

Grout Vents

Materials - Anchorages Permanent Cap Positive Seal Integral Vent Positive Duct Connections

Materials - Vents & Drains Positive Shut-Off Reopen & Close Grouting Pressure

Grouted Duct VSL decided few years ago to carry out an extensive R & D program on grout to review the Grout Mix Design, Procedures, Equipment and Personnel on the impact of grout We will show you selected results of the R&D program

Completed Girder

Summary Extend practical span range of precast/prestressed girders to 225’ Solve handling problem with segmentation: Spliced Girders Final girder is erected as ordinary precast/pretensioned girder No additional complexity for contactor

Project Status Phase I: Concept design Complete Phase II: Standard drawings & details Phase III: Design examples Awaiting release by PennDOT

Questions? Developer of Standards and Design Examples Roy L. Eriksson, P.E. Eriksson Technologies, Inc. Tampa, FL LRFD.com