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I-75 over STRAITS OF MACKINAC

Map

Coordinates:
+45.83684, -84.72481
45°50'13" N, 84°43'29" W

Facts

Source: National Bridge Inventory. Information not verified; use at your own risk.
Name:I-75 over STRAITS OF MACKINAC
Structure number:000000000002456
Old structure number:24186000000B010 (from 1992 edition)
Location:MACKINAW CITY-ST IGNACE
Purpose:Carries highway over waterway
Route classification:Principal Arterial - Interstate (Rural) [01]
Tolls:Yes [1]
Length of largest span:3801.0 ft. [1158.5 m]
Total length:19248.6 ft. [5866.7 m]
Roadway width between curbs:47.9 ft. [14.6 m]
Deck width edge-to-edge:53.8 ft. [16.4 m]
Vertical clearance below bridge:134.5 ft. [41.0 m]
Owner:State Toll Authority [31]
Year built:1957
Historic significance:Bridge is on the National Register of Historic Places [1]
Design load:MS 18 / HS 20 [5]
Number of main spans:3
Main spans material:Steel [3]
Main spans design:Suspension [13]
Deck type:Concrete Cast-in-Place [1]
Wearing surface:Bituminous [6]

Latest Available Inspection: July 2018

Good/Fair/Poor Condition:Fair
Status:Open, no restriction [A]
Average daily traffic:11,076 [as of 2007]
Truck traffic:7% of total traffic
Deck condition:Satisfactory [6 out of 9]
Superstructure condition:Very Good [8 out of 9]
Substructure condition:Very Good [8 out of 9]
Structural appraisal:Equal to present desirable criteria [8]
Deck geometry appraisal:Basically intolerable requiring high priority of replacement [2]
Water adequacy appraisal:Superior to present desirable criteria [9]
Roadway alignment appraisal:Superior to present desirable criteria [9]
Channel protection:There are no noticeable or noteworthy deficiencies which affect the condition of the channel. [9]
Pier/abutment protection:Navigation protection not required [1]
Scour condition:Bridge foundations determined to be stable for the assessed or calculated scour condition. [8]
Sufficiency rating:56.0

Previous Inspections

DateConditionDeckSuperstructureSubstructureADTSuff. Rating
July 2018FairSatisfactoryVery GoodVery Good1107656.0
July 2017FairSatisfactoryFairSatisfactory1107645.0
July 2016FairSatisfactoryVery GoodGood1107656.0
July 2015FairSatisfactoryVery GoodGood1107656.0
July 2014FairSatisfactoryVery GoodGood1107656.0
August 2013FairSatisfactoryVery GoodGood1107656.0
July 2012FairSatisfactoryVery GoodGood1107656.0
July 2009FairSatisfactoryVery GoodGood1107656.0
July 2008FairSatisfactoryVery GoodGood1107656.0
August 2006FairSatisfactoryVery GoodGood1239856.0
August 2004GoodVery GoodExcellentGood1200056.0
July 2002GoodVery GoodExcellentGood1200053.0
August 1990GoodGoodGoodGood1200053.0

Element Data

Source: National Bridge Elements dataset, 2019 edition. This feature is experimental.
ElementUnitsQuantity1-Good2-Fair3-Poor4-Serious
Superstructure
Steel Stringerlinear ft.133,401117,39313,3402,6680
Steel Protective Coatingsq. ft.960,724826,22396,07238,4290
Deck
Reinforced Concrete Decksq. ft.525,337520,0845,25300
Wearing Surfacessq. ft.689,836655,34434,49200
Superstructure
Steel Trusslinear ft.35,07828,7646,31400
Steel Protective Coatingsq. ft.999,999849,999110,00040,0000
Steel Main Cablelinear ft.15,20014,59260800
Steel Protective Coatingsq. ft.97,28068,09629,18400
Steel Secondary Cableeach72,80061,88010,92000
Steel Protective Coatingsq. ft.131,94685,76532,98713,1940
Steel Floor Beamlinear ft.31,18629,3151,2476240
Steel Protective Coatingsq. ft.513,379395,30292,40815,40110,268
Steel Pin or Pin & Hangar Assemblyeach126600
Steel Gusset Plateeach3,6083,10350500
Steel Protective Coatingsq. ft.55,24343,6428,2863,3150
Substructure
Reinforced Concrete Columneach7064600
Steel Column Tower/Trestlelinear ft.1,046858157310
Steel Protective Coatingsq. ft.999,999749,999170,00080,0000
Reinforced Concrete Pier Walllinear ft.6536074600
Reinforced Concrete Pier Caplinear ft.1,4751,28319200
Deck
Open Grid Decksq. ft.214,60060,08883,69468,6722,146
Steel Protective Coatingsq. ft.214,60025,75253,65098,71636,482
Concrete Filled Grid Decksq. ft.185,000120,25046,25018,5000
Joints
Pourable Jointlinear ft.4,7524741,4261,902950
Assembly without Seal Jointlinear ft.1,141947171230
Other Jointlinear ft.4,9144912,9491,4740
Bearings
Movable Bearingeach1,7991,1653992350
Fixed Bearingeach2,1112,0852600
Bridge Rail
Steel or Aluminum Bridge Raillinear ft.36,68331,5472,5682,5680
Steel Protective Coatingsq. ft.199,345161,46927,9089,9680