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