St. Croix River Crossing Project

Public Information Meeting

St. Croix River Crossing Project

Public Information Meeting

St. Croix River Crossing, Preliminary Engineering St. Croix River Crossing, Preliminary Engineering and Design Criteria and Design Criteria Mn/DOT Contract No. 92530Mn/DOT Contract No. 92530

Project ElementsProject ElementsProject ElementsProject Elements

Extradosed Extradosed spansspans

MN approach spans and MN approach spans and rampsramps

General Study DescriptionGeneral Study Description

• Evaluating the design and making refinements to enhance Evaluating the design and making refinements to enhance safety, and life cycle operations and maintenance of the safety, and life cycle operations and maintenance of the structure.structure.

– Verify the structural sufficiency and feasibility of the conceptual bridge design as summarized in the Visual Quality Manual.

– Evaluating a number of options related to the sizes of structural members with the goal of reducing cost while maintaining the overall appearance as outlined in the Visual Quality Manual.

– Evaluating the constructability of the concept design and recommending appropriate refinements.

• Coordination of these efforts with appropriate agencies, Coordination of these efforts with appropriate agencies, stakeholders and the general publicstakeholders and the general public

• Prepare technical documents that will be used by the Prepare technical documents that will be used by the Minnesota Department of Transportation to prepare a Minnesota Department of Transportation to prepare a solicitation for the final design and construction of the bridge.solicitation for the final design and construction of the bridge.

ProgressProgress Images ImagesProgressProgress Images Images

View of refined 3-column form

Road deck view

View along exterior barrier

View along north side at tower

Elements Under StudyElements Under StudyElements Under StudyElements Under Study • Two vs. three column configuration

– The goal is to delete the center column if structurally possible.

• Two vs. three column configuration

– The goal is to delete the center column if structurally possible.

• One vs. two box girder configuration and depth of structure

– The two box option requires struts be placed between them.– The option will be selected based upon cost and constructability

issues.– The depth of the box girders is also being studied with the goal to

reduce depth and overall cost

• One vs. two box girder configuration and depth of structure

– The two box option requires struts be placed between them.– The option will be selected based upon cost and constructability

issues.– The depth of the box girders is also being studied with the goal to

reduce depth and overall cost

Two column configuration Three column configuration

One box girder Two box girders

Elements Under StudyElements Under StudyElements Under StudyElements Under Study

• Cable attachment (exposed vs. covered)Cable attachment (exposed vs. covered)• Cable attachment (exposed vs. covered)Cable attachment (exposed vs. covered)

Exposed cable attachment Covered cable attachment

• Pedestrian railing and path lighting design• Bridge aesthetic lighting design• Color selections

• Pedestrian railing and path lighting design• Bridge aesthetic lighting design• Color selections

Additional Study and Design EffortsAdditional Study and Design EffortsAdditional Study and Design EffortsAdditional Study and Design Efforts

Loop Trail Loop Trail

Inboard of TowersInboard of Towers

Loop Trail Loop Trail

Inboard of TowersInboard of Towers

View looking along trail

Potential overlook plaza at tower

Loop Trail Outboard of TowersLoop Trail Outboard of TowersLoop Trail Outboard of TowersLoop Trail Outboard of Towers

View looking along trail

Trail widening at tower