Region One Bridge Design Robert Jose Tovar If

Region One Bridge Design – Robert Jose Tovar “If I have seen further it is by standing upon the shoulders of giants” – Isaac Newton

Hwy 2 Over Marine Drive – Bridge Replacement using Precast Segmental Tubs

Project Review Project Development Construction Issues Trapezoidal box Girders

Project Background 2009 Job Transportation Act • June 2009 -- EB Frontage Road Widening to three lanes • April 2011 -- Phase I Troutdale Interchange widen EB Exit Ramp to three lanes • December 2013 -- Phase II Troutdale Interchange improve Marine Drive five lanes

Project Background – Traffic Management Plan

Marine Drive - Existing Bridges

Roadway Design Issues Improve Marine Drive from 2 lanes to 5 lanes with sidewalk Increase Vertical Clearance to 16’-0” or 17’-4” No vertical abutments Single Span desirable Limited time for detours for Marine Drive Roadway alignment shift required to eliminate temporary bridge.

T S & L Design Span Length 130 feet. Replace two existing structures with One. Shallow Superstructure depth to 5’-0”. L/D ratio 26. Review post-tensioning concrete and steel design. Concrete option use 52 inch tubs BR 133.

TS&L Alternates – Post-Tension Concrete vs Steel

Construction Sequence

Previous 52 inch-Segmental Bridges Barger Ave – 134 ft. Royal Ave -118 ft.

Project Team Recommends Concrete

Construction Issues Post-tensioning Duct Resetting Bearing Closure pour – Special Concrete Segmental Construction Specifications Construction conflict resolution using 3 D graphics

Post-Tensioning Duct Size • AVAR ACS 22. 6 use 4 inch duct

Wasger Davis S-22. 6 use a 4 ½” Duct Size • Design Deviation required for duct to web ratio greater than 0. 4 AASHTO.

Post-tension Duct & Stressing Duct ratio > 0. 4 need a design deviation ask for 0. 45 Actual duct ratio is 0. 425 Change P/T location to reduce stresses Use Alternate End Stressing approved. Block out required and planned.

Block out for P/T use mechanical splicing anchors

Reset Bearing after 45 days P/T. What? • Can we reduce days down? 30 days? 14 days?

Recommend Using PTFE Elastomeric or Cotton Duck Bearings

Concrete Splice Material – Slump 8 inches Min. • Recommend Special bid item CPC 5000 – Closure Pour Concrete 5000 psi • Future ODOT may want to consider Self-Consolidating Concrete (J-Ring)

Segmental Concrete Bridge Specifications Recommend new Prestress Specification Falsework (Piles, or spread footing) Bracing requirements Girder Handling and Erection Plan Splice Concrete requirements Elevation bearing control

Conflict Resolution Using 3 D- Pdf

Conflict Resolution Continue • Temporary falsework pile redesigned due to conflict with existing footing.

Trapezoidal Box Girders ODOT History and Standard Details Concrete P/T Segmental Design Software review Other Trapezoidal Box Girder Review

ODOT Tub History – All Single Span Washburn (BR_17446) – 175 feet, 76 inch Barger Ave (BR_17474) – 134 feet, 64 inch Wilsonville (BR_17995) – 140 feet, 52 inch Chenowith (BR_18153) – 182 feet, 70 inch Royal Ave (BR_17945) – 118 feet, 52 -inch Mt. Hood Meadows (BR_18571) – 132 feet. 64 inch Marine Dr. (BR_21816) – 130 feet, 52 -inch

ODOT History and Standard Details Designed developed in the middle 1990’s. BR 133 Web is 10 inches, bottom slab 7’-0”. Span range 125 to 175 single span Weight 1. 6 to 2. 12 kips/foot Precast vs Cast-in-Place(5 ksi)

Software Requirements Segmental Design Pre-stressed with Post-tensioning Multiple Stage Post-tension Tapered Girders

Midas Software – 2003 ODOT to Replace Bridge 2 D

Other U girders review PCI Zone 6 Spliced U-Girder Spliced U Girder P/T - Oregon, Colorado & Florida Pre-stressed U Girders – Washington, Texas and Colorado

Other Smaller Pre-stressed U-Girders

LRT (Bybee) Widening- Spliced U Girder

Challenges of using Trapezoidal Box Girders Designing complex structure stating using P/T and tracking pre-stressed losses, software. Stage construction, temporary tower locations. Heavy Girders, requiring girder erection plans. Higher construction support, camber and grade control.

Why Use Trapezoidal Box Girders? High span to depth ratio for increase vertical clearance Good replacement for Cast in Place Post-tensioning. Girders are in 6 inch increments for better designs. Conventional Construction techniques. Aesthetics – reduced girders lines and tapered girder Torsional Stiff for curved girder optional

Thank You – Comments?