SR 18 over I 20


+32.29259, -90.26694
32°17'33" N, 90°16'01" W


Source: National Bridge Inventory. Information not verified; use at your own risk.
Name:SR 18 over I 20
Structure number:31000180250556B
Location:SR 18 OVER I 20
Purpose:Carries highway over highway
Route classification:Other Principal Arterial (Urban) [14]
Length of largest span:102.0 ft. [31.1 m]
Total length:337.9 ft. [103.0 m]
Roadway width between curbs:40.4 ft. [12.3 m]
Deck width edge-to-edge:44.0 ft. [13.4 m]
Vertical clearance below bridge:16.4 ft. [5.0 m]
Skew angle:10°
Owner:State Highway Agency [01]
Year built:1969
Historic significance:Bridge is not eligible for the National Register of Historic Places [5]
Design load:MS 18+Mod / HS 20+Mod [6]
Number of main spans:4
Main spans material:Concrete continuous [2]
Main spans design:Box Beam or girders - Single or Spread [06]
Deck type:Concrete Cast-in-Place [1]

Latest Available Inspection: May 2018

Good/Fair/Poor Condition:Fair
Status:Open, no restriction [A]
Average daily traffic:17,000 [as of 2017]
Truck traffic:3% of total traffic
Deck condition:Fair [5 out of 9]
Superstructure condition:Fair [5 out of 9]
Substructure condition:Very Good [8 out of 9]
Structural appraisal:Somewhat better than minimum adequacy to tolerate being left in place as is [5]
Deck geometry appraisal:Better than present minimum criteria [7]
Underclearances appraisal:Meets minimum tolerable limits to be left in place as is [4]
Roadway alignment appraisal:Equal to present desirable criteria [8]
Scour condition:Bridge not over waterway. [N]
Sufficiency rating:77.0

Previous Inspections

DateConditionDeckSuperstructureSubstructureADTSuff. Rating
May 2018FairFairFairVery Good1700077.0
May 2016FairFairFairVery Good1500077.2
June 2014FairFairFairVery Good1750080.0
May 2012FairFairFairVery Good1600080.1
May 2010FairFairFairVery Good1550080.1
May 2008FairSatisfactoryVery GoodVery Good1750092.1
October 2006FairSatisfactoryVery GoodVery Good1750092.1
July 2004GoodGoodVery GoodVery Good1300094.4
August 2002GoodGoodVery GoodVery Good1400094.3
August 2000GoodGoodVery GoodVery Good1200094.4
July 1998GoodGoodVery GoodVery Good1200094.4
September 1996GoodGoodVery GoodVery Good1200095.0
December 1994GoodGoodVery GoodVery Good1200093.0
February 1993GoodGoodVery GoodVery Good1158093.0
March 1991GoodGoodVery GoodVery Good1072093.0

Element Data

Source: National Bridge Elements dataset, 2019 edition. This feature is experimental.
Reinforced Concrete Closed Web/Box Girderlinear ft.338033800
Reinforced Concrete Top Flangesq. ft.14,85507,4287,4270
Reinforced Concrete Abutmentlinear ft.167167000
Assembly with Sealeach8585000
Movable Bearingeach1400140
Steel Protective Coatingsq. ft.1400014
Bridge Rail
Reinforced Concrete Bridge Raillinear ft.676676000