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Martin Luther King, Jr. Blvd. Viaduct, Portland. Project Background and Today’s Design Status. Location – Looking Southeast. Closer View - Looking Southeast. Historic Background - MLK. MLK (Union Ave.) built 1938 H-15 Design Live Load. Historic Background – Grand. Grand Ave. built 1964
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Martin Luther King, Jr. Blvd. Viaduct, Portland • Project Background and Today’s Design Status
Historic Background - MLK • MLK (Union Ave.) built 1938 • H-15 Design Live Load
Historic Background – Grand • Grand Ave. built 1964 • HS-20 Design Live Load
Early Problems • Crosses Filled-In Slough • Wood Waste • Timber Piles Not Driven Deep Enough • Partial Structure Settlement • ACWS Added to Raise Grade • Jacking Attempt after cutting columns. Instead of raising the structure, it lowered the footings.
Today’s Conditions • Structure Settlement, Translation & Deterioration • Sufficiency Ratings • MLK 19, Grand Ave. 60 (out of 100) • SB Weight Restrictions (50,000 lb) • Ongoing Maintenance
Stakeholder & Architectural Goals 1 • Environmental Assessment & 4(f) Evaluation Process 2001-2002 • Design Review Advisory Committee (DRAC) • Improved Vehicular Access • Improved Ped. & Bike Access • Traffic Calming • Landscaping, Planters on Structure
Stakeholder & Architectural Goals 2 • Access to Springwater Trail • Gateway to SE Portland • Appearance Reminiscent of Existing Structure • Shorter, Haunched Spans 24 m (80 ft) • Deck Overhangs • Historic Lighting Fixtures • Historic Interpretive Signs (in pylons) • Improved Ped. & Bike Access
Stakeholder & Architectural Goals 3 • Architectural Rails • Open for Outward Visibility • “Not like the Ross Island Bridge” • Must meet LRFD Strength & Performance • Similar to FHWA Crash-Tested Rail • FHWA Concurrence • Keep Adjacent Businesses Open • Cross Existing UPRR • Future Light Rail Transit Beneath
Bridge Replacement Concept Studies (1999-2001) • Replace MLK Structure on Existing Alignment • Highway Standards • 45 mph, 3.6 m Lanes, Std. Metal Rails • Prestressed Concrete Girders • Approx. 36 m (120 ft.) Spans
New Alignment Alternatives • Boulevard (35 mph) Standards • Grade Separated Alternative (Chosen) • Signalized Alternative (Not Chosen) • 3.3 m Lanes, 1.2 m & 1.8 m Shoulders • Tight Curves: Shorter Bridge, Less Skew • Substandard Horizontal Alignment • Accepted By City of Portland via IGA • Ownership Transfers to Portland Upon Completion
Engineering Solutions • Replace MLK Struct., Rehab Grand • TS&L (Sept. 2003): Replace Grand? • Approx. $3 million extra • Best time to replace during this project • Wouldn’t have to remove rails, etc. later • But, existing structure didn’t meet criteria to replace (SR > 50) • Not in original scope • Not in the budget
Stage Construction Challenges • Narrow Lanes & Shld. on New Struct. • Restricted Right-of-Way • Traffic Volumes (60,000+ ADT) • Maintain 4 Lanes During Construction • Temporary Detour Structure (partial)
Superstructure • Precast P/S Slab/Box Girders • Fits Desired Span Lengths (75’-80’) • Haunched for Architectural Appearance • Quicker to Build, No Falsework Req’d. • Good Structure Economy • Spread Boxes w/ Cast Deck • Has Been Done Before • North 3 Spans CIP P/T Box Girder • Flared, Curved, Skewed
Span Layout Issues • Repetitive Spans Promote Economy • Try To Avoid Existing Bents • Many Utilities, Buried and Overhead • Resulting Spans Weren’t Equal
Foundation Conditions • Silt Overburden Layer • Seismic Settlement & Amplification • Use Steel H-Piles • Driven into Troutdale Gravel Layer • Approx. 15-20 m deep North & South • Approx. 25-30 m deep at wood waste • MSE Wire Retaining Walls • CIP Architectural Facing, After Settlement
Logistical Challenges During Design • Decentralization of ODOT in 2004 • Designers/Drafters in: • Region 1, Portland • Region 2, East Salem • ODOT HQ, Salem • Minimal Traffic Control Design Begun • DEA, Inc. Recruited for Traffic Control Design, Drafting, Lead Structure Design
Evolving Bid Schedule • November 2005: Change of Course • Cost of Grand rehab approached replacement cost • Decision to Replace Grand Ave. • Split Contracts • March 9, 2006 bid for earthwork, drainage, utilities ($5 million) • Nov. 2006 bid for structure and retaining walls
Innovative Contracting Methods • Complex Project with Significant Risk Elements • Want an experienced contractor with innovative abilities • Think it through ahead of time
Innovative Contracting, cont. 1 • Best Value Bid Process (A+C+D) on Structure Work • “A” Component: Price (40%) • “C” Component: Qualifications (40%) • “D” Component: Tech. Approach (20%) • Not Used: “B” Component (Time)
Innovative Contracting, cont. 2 • ODOT Experience with Best Value Contracting: • I-5 Interstate Bridge Lift Span Trunnion Replacement (1997) • St. Johns Bridge Rehabilitation (2003-05) • Both Were A+C • Procedure now in place at Office of Procurement to streamline Best Value Contracting
Philosophical Considerations • Budget Limitations • $32 million available from Bridge Program • Scope creep • Project now approx. $50 million range • Unfunded Stakeholder Demands • Awareness of Project Scope • Grand Ave. not part of original scope
Philosophical Considerations cont. • Context Sensitive Solutions • Was the original scope realistic considering the setting? • Old industrial area vs. redevelopment visions • Transportation impacts on communities • Cause urban blight vs. enhancement