National Bridge Inventory [NBI] - Data Dictionary
NBI Elements
Item #
|
Description |
Item # |
Description |
1
2
3
4
5
6
7
8
9
10
11
12
13
19
20
21
22
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
State Code
Highway Agency District
County (Parish) Code
Place Code
Inventory Route
Features Intersected
Facility Carried by Structure
Structure Number
Location
Inventory Route, Minimum Vertical Clearance
Kilometer Point
Base Highway Network
LRS Inventory Route, Subroute Number
Bypass, Detour Length
Toll
Maintenance Responsibility
Owner
Functional Classification of Inventory Route
Year Built
Lanes On and Under the Structure
Average Daily Traffic
Year of Average Daily Traffic
Design Load
Approach Roadway Width
Bridge Median
Skew
Structure Flared
Traffic Safety Features
Historical Significance
Navigation Control
Navigation Vertical Clearance
Navigation Horizontal Clearance
Structure Open, Posted or Closed to Traffic
Type of Service
Structure Type, Main
Structure Type, Approach Spans
Number of Spans in Main Unit
Number of Approach Spans
Inventory Route, Total Horizontal Clearance
Length of Maximum Span
Structure Length
Curb or Sidewalk Widths
Bridge Roadway Width, Curb-to-Curb
Deck Width, Out-to-Out
Minimum Vertical Clearance Over Bridge Roadway
Minimum Vertical Underclearance
|
55
56
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
75
76
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
Minimum Lateral Underclearance on Right
Minimum Lateral Underclearance on Left
Deck Condition Rating
Superstructure Condition Ratings
Substructure Condition Ratings
Channel and Channel Protection
Culverts Condition Ratings
Method used to Determine Operating Rating
Operating Rating
Method used to Determine Inventory Rating
Inventory Rating
Structural Evaluation Appraisal Ratings
Deck Geometry Appraisal Ratings
Underclearances, Vertical and Horizontal Appraisal Ratings
Bridge Posting
Waterway Adequacy Appraisal Ratings
Approach Roadway Alignment Appraisal Ratings
Type of Work
Length of Structure Improvement
Inspection Date
Designated Inspection Frequency
Critical Feature Inspection
Critical Feature Inspection Date
Bridge Improvement Cost
Roadway Improvement Cost
Total Project Cost
Year of Improvement Cost Estimate
Border Bridge
Border Bridge Structure Number
STRAHNET Highway Designation
Parallel Structure Designation
Direction of Traffic
Temporary Structure Designation
Highway System of the Inventory Route
Federal Lands Highways
Year Reconstructed
Deck Structure Type
Wearing Surface/Protective System
Average Daily Truck Traffic
Designated National Network
Pier or Abutment Protection [for navigation]
NBIS Bridge Length
Scour Critical Bridges
Future Average Daily Traffic
Year of Future Average Daily Traffic
Minimum Navigation Vertical Clearance
|
|
DEC_AREA
FIPS
FUNCT_OBS
STATUS
STRUCT_DEF
SUFF_RAT
|
NBI Elements > ITEM 1 - State Code: 2 - Digit FIPS only
Code Description
01 Alabama
02 Alaska
04 Arizona
05 Arkansas
06 California
08 Colorado
09 Connecticut
10 Delaware
11 District of Columbia
12 Florida
13 Georgia
15 Hawaii
16 Idaho
17 Illinois
18 Indiana
19 Iowa
20 Kansas
21 Kentucky
22 Louisiana
23 Maine
24 Maryland
25 Massachusetts
26 Michigan
27 Minnesota
28 Mississippi
29 Missouri
30 Montana
31 Nebraska
32 Nevada
33 New Hampshire
34 New Jersey
35 New Mexico
36 New York
37 North Carolina
38 North Dakota
39 Ohio
40 Oklahoma
41 Oregon
42 Pennsylvania
44 Rhode Island
45 South Carolina
46 South Dakota
47 Tennessee
48 Texas
49 Utah
50 Vermont
51 Virginia
53 Washington
54 West Virginia
55 Wisconsin
56 Wyoming
60 American Samoa
66 Guam
69 Northern Marianas
72 Puerto Rico
78 Virgin Islands
NBI Elements > ITEM 2 - Highway Agency District
The highway agency district (State or Federal) in which the bridge is located represented by a 2-digit code.
NBI Elements > ITEM 4 - Place Code
Cities, towns, townships, villages, and other census-designated places identified using the FIPS codes given
in the current version of the Census of Population and Housing - Geographic Identification Code Scheme.
NBI Elements > ITEM 5 - Inventory Route
The inventory route is a 9-digit code composed of 5 segments.
Length Segment Description
1 digit 5A Record Type
1 digit 5B Route Signing Prefix
1 digit 5C Designated level of service
5 digit 5D Route Number
1 digit 5E Directional Suffix
NBI Elements > ITEM 5A - Record Type
There are 2 types of NBI records: "ON" and "UNDER".
Code Description
1 Route carried "ON" the structure
2 Single route goes "UNDER" the sturcture
A - Z Multiple routes go "UNDER" the structure
99 Miscoded data
NBI Elements > ITEM 5B - Record Signing Prefix
Code Description
1 Interstate highway
2 U.S. numbered highway
3 State highway
4 County highway
5 City street
6 Federal lands road
7 State lands road
8 Other
99 Miscoded data
NBI Elements > ITEM 5C - Designated Level of Service
Code Description
0 None of the below
1 Mainline
2 Alternate
3 Bypass
4 Spur
6 Business
7 Ramp, Wye, Connector, etc.
8 Service and/or unclassified frontage road
99 Miscoded data
NBI Elements > ITEM 5D - Route Number
The route number of inventory route in 5 digits, right justified with leading zeros.
NBI Elements > ITEM 5E - Directional Suffix
Code Description
0 N/A
1 North
2 East
3 South
4 West
99 Miscoded data
NBI Elements > ITEM 6A - Features Intersected / ITEM 6B - Critical Facility Indicator
These items contain the description of the features intersected by the structure and a critical facility indicator( no longer coded ).
NBI Elements > ITEM 7 - Facility Carried by Structure
The facility being carried by the structure. In all situations this item describes the use "on" the structure.
NBI Elements > ITEM 8 - Structure Number
A 15 digit structure number unique for each bridge within the state.
NBI Elements > ITEM 9 - Location
A narrative description of the bridge location.
NBI Elements > ITEM 10 - Inventory Route, Minimum Vertical Clearance
The minimum vertical clearance over the inventory route identified in Item 5, whether the route is "on" the structure
or "under" the structure. Measured in meters.
NBI Elements > ITEM 11 - Kilometerpoint
The linear referencing system(LRS) kilometerpoint is used to establish the location of the bridge on the
Base Highway Network(Item 12).
NBI Elements > ITEM 12 - Base Highway Network
The Base Highway Network includes the through lane(mainline) portions of the NHS, rural/urban principal arterial system
and rural minor arterial system. Ramps, frontage roads and other roadways are not included in the Base Network.
Code Description
0 Inventory route is not on the Base Network
1 Inventory route is on the Base Network
99 Miscoded data
NBI Elements > ITEMS 13A, 13B - LRS Inventory Route, Subroute Number
If Item 12 - Base Highway Network has been coded 1, the information to be recorded for this item is inventory route for
the State's linear referencing system(LRS). If Item 12 has been coded 0, this entire item is left blank.
NBI Elements > ITEM 19 - Bypass, Detour Length
The actual length to the nearest kilometer of the detour length. It is the total additional travel for a vehicle
which would result from closing of the bridge.
NBI Elements > ITEM 20 - Toll
Code Description
1 Toll bridge. Tolls are paid specifically to use the structure.
2 On toll road. The structure carries a toll road, i.e. tolls are paid to the facility, which includes
both the highway and the structure.
3 On free road. The structure is toll-free and carries a toll-free highway.
4 On Interstate toll segment under Secretarial Agreement. Structure functions as a part of
the toll segment.
5 Toll bridge is a segment under Secretarial Agreement. Structure is seperate agreement
from highway segment.
99 Miscoded data
NBI Elements > ITEMS 21, 22 - Maintenance Responsibility / Owner
Code Description
01 State Highway Agency
02 County Highway Agency
03 Town or Township Highway Agency
04 City or Municipal Highway Agency
11 State Park, Forest, or Reservation Agency
12 Local Park, Forest, or Reservation Agency
21 Other State Agencies
25 Other Local Agencies
26 Private (other than railroad)
27 Railroad 31 State Toll Authority
32 Local Toll Authority
60 Other Federal Agencies (not listed below)
61 Indian Tribal Government
62 Bureau of Indian Affairs
63 Bureau of Fish and Wildlife
64 U.S. Forest Service
66 National Park Service
67 Tennessee Valley Authority
68 Bureau of Land Management
69 Bureau of Reclamation
70 Corps of Engineers (Civil)
71 Corps of Engineers (Military)
72 Air Force
73 Navy/Marines
74 Army
75 NASA
76 Metropolitan Washington Airports Service
80 Unknown
99 Miscoded data
NBI Elements > ITEM 26 - Functional Classification of Inventory Route
Code Description
Rural
01 Principal Arterial - Interstate
02 Principal Arterial - Other
06 Minor Arterial
07 Major Collector
08 Minor Collector
09 Local
Urban
11 Principal Arterial - Interstate
12 Principal Arterial - Other Freeways or Expressways
14 Other Principal Arterial
16 Minor Arterial
17 Collector
19 Local
99 Miscoded data
NBI Elements > ITEM 27 - Year Built
Year of construction of the structure.
NBI Elements > ITEMS 28A, 28B - Lanes On and Under the Structure
Number of lanes being carried by the structure and being crossed over by the structure.
NBI Elements > ITEM 29 - Average Daily Traffic
Average daily traffic volume for the inventory route identified in Item 5.
NBI Elements > ITEM 30 - Year of Average Daily Traffic
Year represented by the ADT(Item 29).
NBI Elements > ITEM 31 - Design Load
Code Metric / English Description
1 M 9 / H 10
2 M 13.5 / H 15
3 MS 13.5 / HS 15
4 M 18 / H 20
5 MS 18 / HS 20
6 MS 18+Mod / HS 20+Mod
7 Pedestrian
8 Railroad
9 MS 22.5 / HS 25
0 Other or Unknown
99 Miscoded data
NBI Elements > ITEM 32 - Approach Roadway Width
Normal width of usable roadway approaching the structure measured in meters.
NBI Elements > ITEM 33 - Bridge Median
Code Description
0 No median
1 Open median
2 Closed median(no barriers)
3 Closed median with non-mountable barriers
99 Miscoded data
NBI Elements > ITEM 34 - Skew
The skew angle is the angle between the centerline of a pier and a line normal to the roadway centerline.
Major variation in skews of substructure units is indicated with 99.
NBI Elements > ITEM 35 - Structure Flared
Flared = width of structure varies.
Code Description
0 No flare
1 Yes, flared
99 Miscoded data
NBI Elements > ITEM 36 - Traffic Safety Features
Bridge inspection shall include the recording of information on the following traffic safety features
so that the evaluation of their adequacy can be made.
Segment Description
36A Bridge railings
36B Transitions
36C Approach guardrail
36D Approach guardrail ends
The reporting of these features shall be as follows:
Code Description
0 Inspected feature does not meet currently acceptable stds. or a safety feature is required and none is provided.*
1 Inpected peature meets currently acceptable standards.*
N Not applicable or a safety feature is not required.*
99 Miscoded data
* For structures on the NHS, national standards are set by regulation. For those not on the NHS, it shall be
the responsibility of the highway agency (state, county, local or federal) to set standards.
NBI Elements > ITEM 37 - Historical Significance
Code Description
1 Bridge is on the National Register of Historic Places(NRHP).
2 Bridge is eligible for the NRHP.
3 Bridge is possibly eligible for the NRHP(requires further investigation before determination can be made)
or bridge is on a State or local historic register.
4 Historical significance is not determinable at this time.
5 Bridge is not eligible for the NRHP.
99 Miscoded data
NBI Elements > ITEM 38 - Navigation Control
Code Description
N Not applicable, no waterway.
0 No navigation control on waterway(bridge permit not required).
1 Navigation control on waterway(bridge permit required).
99 Miscoded data
NBI Elements > ITEM 39 - Navigation Vertical Clearance
If Item 38 - Navigation Control has been coded 1, clearance is the minimum vertical clearance imposed at the site as
measured above a datum that is specified on a navigation permit issued by a control agency. Measured in meters.
NBI Elements > ITEM 40 - Navigation Horizontal Clearance
If Item 38 - Navigation Control has been coded 1, clearance is the horizontal clearance imposed at the site that is shown
on the navigation permit. Measured in meters.
NBI Elements > ITEM 41 - Structure Open, Posted or Closed to Traffic
Code Description
A Open, no restriction
B Open, posting recommended but not legally implemented (all signs not in place or not correctly implemented)
D Open, would be posted or closed except for temporary shoring, etc. to allow for unrestricted traffic
E Open, temporary structure in place to carry legal loads while original structure is closed and awaiting
replacement or rehabilitation
G New structure not yet open to traffic
K Bridge closed to all traffic
P Posted for load (may include other restrictions such a temporary bridges which are load posted)
R Posted for other load-capacity restriction (speed, number of vehicles on bridge, etc.)
99 Miscoded data
NBI Elements > ITEMS 42A, 42B - Type of Service On / Under bridge
Type of Service On Bridge
Code Description
1 Highway
2 Railroad
3 Pedestrian-bicycle
4 Highway-railroad
5 Highway-pedestrian
6 Overpass structure at an interchange or second level of a multilevel interchange
7 Third level (Interchange)
8 Fourth level (Interchange)
9 Building of plaza
0 Other
99 Miscoded data
Type of Service under Bridge
Code Description
1 Highway, with or without pedestrian
2 Railroad
3 Pedestrian-bicycle
4 Highway-railroad
5 Waterway
6 Highway-waterway
7 Railroad-waterway
8 Highway-waterway-railroad
9 Relief for waterway
0 Other
99 Miscoded data
NBI Elements > ITEMS 43A, 44A - Kind of material, Main / Approach
Code Description
1 Concrete
2 Concrete continuous
3 Steel
4 Steel continuous
5 Prestressed concrete *
6 Prestressed concrete continuous *
7 Wood or timber
8 Masonry
9 Aluminum, Wrought Iron or Cast Iron
0** Other
99 Miscoded data
* Post-tensioned concrete coded as prestressed concrete
** Not applicable for Item 44
NBI Elements > ITEMS 43B, 44B - Type of Design, Main / Approach
Code Description
01 Slab
02 Stringer/Multi-beam or girder
03 Girder and floorbeam system
04 Tee beam
05 Box beam or girders - Multiple
06 Box Beam or girders - Single or Spread
07 Frame
08 Orthotropic
09 Truss - Deck
10 Truss - Thru
11 Arch - Deck
12 Arch - Thru
13 Suspension
14 Stayed girder
15 Movable - Lift
16 Movable - Bascule
17 Movable - Swing
18 Tunnel
19 Culvert
20* Mixed types
21 Segmental box girder
22 Channel beam
00** Other
99 Miscoded data
* Applicable to only approach spans - Item 44.
** Not applicable for Item 44
NBI Elements > ITEM 45 - Number of Spans in Main Unit
Number of spans in the main or major unit.
NBI Elements > ITEM 46 - Number of Approach Spans
Number of spans in the approach spans to the major bridge, or the number of spans of material different
from that of the major bridge.
NBI Elements > ITEM 47 - Inventory Route, Total Horizontal Clearance
The total horizontal clearance for the inventory route identified in Item 5 measured in meters. It is the available
clearance measured between the restrictive features -- curbs, rails, walls, piers or other structural features limiting the
roadway (surface and shoulders). When the restriction is 100 meters or greater, code could be 999.
NBI Elements > ITEM 48 - Length of Maximum Span
The length of maximum span. It shall be noted whether the measurement is center of bearing points or clear open distance between
piers, bents or abutments. The measurement shall be along the centerline of the bridge. Measured in meters.
NBI Elements > ITEM 49 - Structure Length
The length of the structure measured in meters. This shall be the length of roadway which is supported on the bridge structure.
The length is measured back to back of backwalls of abutments or from paving notch to paving notch. Culvert lengths are measured along
the center line of roadway regardless of their depth below grade. Measurement is made between inside faces of exterior walls. Tunnel
length is measured along the centerline of the roadway.
NBI Elements > ITEMS 50A, 50B - Curb or Sidewalk Widths (Left / Right)
The widths of the left and right curbs or sidewalks measured in meters. "Left" and "Right" is determined on the basis of
direction of the inventory.
NBI Elements > ITEM 51 - Bridge Roadway Width, Curb-to-Curb
The most restrictive minimum distance between curbs or rails on the structure roadway measured in meters.
NBI Elements > ITEM 52 - Deck Width, Out-to-Out
The out-to-out width measured in meters.
NBI Elements > ITEM 53 - Minimum Vertical Clearance Over Bridge Roadway
The actual minimum vertical clearance over the bridge roadway, including shoulders, to any superstructure restriction,
measured in meters. When no superstructure restriction exists above the bridge roadway, or when a restriction
is 30 meters or greater, indicated as 99.99.
NBI Elements > ITEM 54A - Minimum Vertical Underclearance - Reference feature
The reference feature from which the clearance measurement is taken:
Code Description
H Highway beneath structure
R Railroad beneath structure
N Feature not a highway or railroad
99 Miscoded data
NBI Elements > ITEM 54B - Minimum Vertical Underclearance
The minimum vertical clearance from the roadway(travel lanes only) or railroad track beneath the structure to the
underside of the superstructure. Measured in meters.
NBI Elements > ITEM 55A - Minimum Lateral Underclearance - Reference feature
The reference feature from which the clearance measurement is taken:
Code Description
H Highway beneath structure
R Railroad beneath structure
N Feature not a highway or railroad
99 Miscoded data
NBI Elements > ITEM 55B - Minimum Lateral Underclearance on Right
The minimum lateral underclearance on the right measured in meters.
NBI Elements > ITEM 56 - Minimum Lateral Underclearance on Left
The minimum lateral underclearance on the left measured in meters.
NBI Elements > ITEMS 58, 59, 60 - Condition ratings: Deck, Superstructure, Substructure
Code Description
N NOT APPLICABLE
9 EXCELLENT CONDITION
8 VERY GOOD CONDITION - no problems noted.
7 GOOD CONDITION - some minor problems.
6 SATISFACTORY CONDITION - structural elements show some minor deterioration.
5 FAIR CONDITION - all primary structural elements are sound but may have minor section loss, cracking,
spalling or scour.
4 POOR CONDITION - advanced section loss, deterioration, spalling or scour.
3 SERIOUS CONDITION - loss of section, deterioration of primary structural elements. Fatigue cracks
in steel or shear cracks in concrete may be present.
2 CRITICAL CONDITION - advanced deterioration of primary structural elements. Fatigue cracks in steel
or shear cracks in concrete may be present or scour may have removed substructure support. Unless
closely monitored it may be necessary to close the bridge until corrective action is taken.
1 "IMMINANT" FAILURE CONDITION - major deterioration or section loss present in critical sructural
components or obvious vertical or horizontal movement affecting structure stability. Bridge is
closed to traffic but corrective action may put it back in light service.
0 FAILED CONDITION - out of service; beyond corrective action.
99 Miscoded data
NBI Elements > ITEM 61 - Channel and Channel Protection
Code Description
N Not applicable.
9 There are no noticeable or noteworthy deficiencies which affect the condition of the channel.
8 Banks are protected or well vegetated. River control devices such as spur dikes and embankment protection
are not required or are in a stable condition.
7 Bank protection is in need of minor repairs. River control devices and embankment protection have a little
minor damage. Banks and/or channel have minor amounts of drift.
6 Bank is beginning to slump. River control devices and embankment protection have widespread minor damage.
There is minor stream bed movement evident. Debris is restricting the channel slightly.
5 Bank protection is being eroded. River control devices and/or embankment have major damage. Trees and
brush restrict the channel.
4 Bank and embankment protection is severely undermined. River control devices have severe damage.
Large deposits of debris are in the channel.
3 Bank protection has failed. River control devices have been destroyed. Stream bed aggradation, degradation
or lateral movement has changed the channel to now threaten the bridge and/or approach roadway.
2 The channel has changed to the extent the bridge is near a state of collapse.
1 Bridge closed because of channel failure. Corrective action may put back in light service.
0 Bridge closed because of channel failure. Replacement necessary.
99 Miscoded data
NBI Elements > ITEM 62 - Culverts
Code Description
N Not applicable. Used if structure is not a culvert.
9 No defeciencies
8 No noticeable or noteworthy deficiencies which affect the condition of the culvert. Insignificant scrape
marks caused by drift.
7 Shrinkage cracks, light scaling and insignificant spalling which does not expose reinforcing steel. Insignificant
damage caused by drift with no misalignment and not requiring corrective action. Some minor scouring has
occured near curtain walls, wingwalls or pipes. Metal culverts have a smooth symmetrical curvature with
superficial corrosion and no pitting.
6 Deterioration or initial disintegration, minor chloride contamination, cracking with some leaching, or spalls
on concrete or masonry walls and slabs. Local minor scouring at curtain walls, wingwalls or pipes. Metal culverts
have a smooth curvature, non-symmetrical shape, significant corrosion or moderate pitting.
5 Moderate to major deterioration or disintegration, extensive cracking and leaching or spalls on concrete
or masonry walls and slabs. Minor settlement or misalignment. Noticeable scouring or erosion at curtain walls,
wingwalls or pipes. Metal culverts have significant distortion and deflection in one section, significant corrosion
or deep pitting.
4 Large spalls, heavy scaling, wide cracks, considerable efflorescence or opened construction joint permitting loss of
backfill. Considerable settlement or misalignment. Considerable scouring or erosion at curtain walls, wingwalls or
pipes. Metal culverts have significant distortion and deflection throughout, extensive corrosion or deep pitting.
3 Any condition described in Code 4 but which is excessive in scope. Severe movement or differential setlement of the
segments or loss of fill. Holes may exist in walls or slabs. Integral wingwalls nearly severed from culvert. Severe
scour or erosion at curtain walls, wingwalls or pipes. Metal culverts have extreme distortion and delection in one
section, extensive corrosion, or deep pitting with scattered perforations.
2 Integral wingwalls collapsed, severe settlement of roadway due to loss of fill. Section of culvert may have failed and
can no longer support embankment. Complete undrmining at curtain walls and pipes. Corrective action required to
maintain traffic. Metal culverts have extreme distortion and deflection and deflection throughout with extensive
perforations due to corrosion.
1 Bridge closed. Corrective action may put back in light service.
0 Bridge closed. Replacement necessary.
99 Miscoded data
NBI Elements > ITEMS 63, 65 - Method Used to Determine: Operating Rating / Inventory Rating
Code Description
1 Load Factor(LF)
2 Allowable Stress(AS)
3 Load and Resistance Factor(LRFR)
4 Load Testing
5 No rating analysis performed
99 Miscoded data
NBI Elements > ITEM 64 - Operating Rating
This capacity rating referred to as the operating rating, will result in the absolute maximum permissible load level to which
the structure may be subjected for the vehicle type used in the rating. Represents the total mass of the entire vehicle
measured in metric tons. If the bridge will not carry a minimum of 2.7 metric tons of live load, the operating rating
is 0 metric tons.
NBI Elements > ITEM 66 - Inventory Rating
This capacity rating referred to as the inventory rating, will result in a load level which can safely utilize an existing
structure for an indefinite period of time. Coded as '999' for a structure under sufficient fill such that, according to
AASHTO design, the live load is insignificant in the structure load capacity.
NBI Elements > ITEMS 67, 68, 69, 71, 72 - Appraisal ratings
- Structural Evaluation
- Deck Geometry
- Underclearances, Vertical and Horizontal
- Water Adequacy
- Approach Roadway Alignment
Code Description
N N/A
9 Superior to present desirable criteria
8 Equal to present desirable criteria
7 Better than present minimum criteria
6 Equal to present minimum criteria
5 Somewhat better than minimum adequacy to tolerate being left in place as is
4 Meets minimum tolerable limits to be left in place as is
3 Basically intolerable requiring high priority of corrrective action
2 Basically intolerable requiring high priority of replacement
1 This value of rating code not used
0 Bridge closed
99 Miscoded data
NBI Elements > ITEMS 70 - Bridge Posting
Code Description
5 Equal to or above legal loads
4 00.1 - 09.9 % below
3 10.0 - 19.9 % below
2 20.0 - 29.9 % below
1 30.0 - 39.9 % below
0 > 39.9% below
99 Miscoded data
NBI Elements > ITEM 75A - Type of Work
Code Description
31 Replacement of bridge or other structure because of substandard load carrying
capacity or substantial bridge roadway geometry.
32 Replacement of bridge or other structure because of relocation of road.
33 Widening of existing bridge or other major structure without deck rehabilitation
or replacement; includes culvert lengthening.
34 Widening of existing bridge with deck rehabilitation or replacement.
35 Bridge rehabilitation because of general structure deterioration or inadequate strength.
36 Bridge deck rehabilitation with only incidental widening.
37 Bridge deck replacement with only incidental widening.
38 Other structural work, including hydraulic replacements.
99 Miscoded data
NBI Elements > ITEM 75B - Work Done By
Code Description
1 Work to be done by contract
2 Work to be done by owner's forces
99 Miscoded data
NBI Elements > ITEM 76 - Length of Structure Improvement
This is the length of the proposed bridge improvement measured in meters.
NBI Elements > ITEM 90 - Inspection Date
This is the month(2-digits) and year(4-digits) of the last routine inspection of the structure performed.
NBI Elements > ITEM 91 - Designated Inspection Frequency
This is the number of months between designated inspections of the structure.
NBI Elements > ITEMS 92A, 92B, 92C - Critical Feature Inspection
- Fracture Critical Details
- Underwater Inspection
- Other Special Inspection
1st digit
Code Description
Y Special inspection or emphasis needed
N Not needed
2nd and 3rd digit
2 - digit number to indicate the number of months between inspections only if the first digit is coded 'Y'.
NBI Elements > ITEMS 93A, 93B, 93C - Critical Feature Inspection Date
If the first digit of Item 92 is coded 'Y' then the first 2 - digits represent the month and last 2 - digits represent
the year that the last inspection of the denoted critical feature was performed.
NBI Elements > ITEM 94 - Bridge Improvement Cost
Estimated cost of the proposed bridge or major structure improvements in thousands of dollars. This cost shall
include only bridge construction costs, excluding roadway, right of way, detour, demolition, prelimnary engineering, etc.
NBI Elements > ITEM 95 - Roadway Improvement Cost
Estimated cost of the proposed roadway improvement in thousands of dollars. This shall include only roadway
construction costs, excluding bridge, right-of-way, detour, extensive roadway realignment costs, preliminary
engineering, etc.
NBI Elements > ITEM 96 - Total Project Cost
Estimated total project costs associated with the proposed bridge improvement project in thousands of
dollars, including incidental costs not included in Items 94 and 95. The total project cost will therefore
be greater than the sum of Items 94 and 95.
NBI Elements > ITEM 97 - Year of Improvement Cost Estimate
The 4 - digit year that the costs of work estimated in Items 94, 95 and 96 were based upon.
NBI Elements > ITEM 98 - Border Bridge
This item indicates structures crossing borders of States.
Segment Description
98A Neighboring State Code[ 3 digits ]
98B Percent Responsibility*[ 2 digits ]
* - Percentage of total deck area of the existing bridge that the neighboring State is responsible for funding.
If the structure is not on a border, left blank.
NBI Elements > ITEM 99 - Border Bridge Structure Number
This item indicates neighboring State's 15-Digit NBI structure number for any structure noted in Item 98.
Blank if Item 98 is blank.
NBI Elements > ITEM 100 - STRAHNET Highway Designation
Code Description
1 The inventory route is not a STRAHNET route.
2 The inventory route is on a Interstate STRAHNET route.
3 The inventory route is on a Non-Interstate STRAHNET route.
4 The inventory route is on a STRAHNET connector route.
99 Miscoded data
NBI Elements > ITEM 101 - Parallel Structure Designation
Code Description
R The right structure of parallel bridges carrying the roadway in the direction of the inventory.
( For a STRAHNET highway, this is west to east and south to north. )
L The left structure of parallel bridges. This structure carries traffic in the opposite direction.
N No parallel structure exists.
99 Miscoded data
NBI Elements > ITEM 102 - Direction of Traffic
Code Description
0 Highway traffic not carried
1 1 - way traffic
2 2 - way traffic
3 One lane bridge for 2 - way traffic
99 Miscoded data
NBI Elements > ITEM 103 - Temporary Structure Designation
Code Description
T Temporary structure(s) or conditions exist.
99 Miscoded data
Blank if not applicable.
NBI Elements > ITEM 104 - Highway System of the Inventory Route
Code Description
0 Inventory Route is not on the NHS.
1 Inventory Route is on the NHS.
99 Miscoded data
NBI Elements > ITEM 105 - Federal Lands Highway
Code Description
0 N/A
1 Indian Reservation Road (IRR)
2 Forest Highway (FH)
3 Land Management Highway System (LMHS)
4 Both IRR and FH
5 Both IRR and LMHS
6 Both FH and LMHS
9 Combined IRR, FH and LMHS
99 Miscoded data
NBI Elements > ITEM 106 - Year Reconstructed
4 - digit year of most recent reconstruction of the structure. If there has been no reconstruction, year is 0.
NBI Elements > ITEM 107 - Deck Structure Type
Code Description
1 Concrete Cast-in-Place
2 Concrete Precast Panels
3 Open Grating
4 Closed Grating
5 Steel plate (includes orthotropic)
6 Corrugated Steel
7 Aluminum
8 Wood or Timber
9 Other
N Not applicable
99 Miscoded data
NBI Elements > ITEM 108 - Wearing Surface/Protective System
Information on the wearing surface and protective system of the bridge deck is composed of 3 segments.
Length Segment Description
1 digit 108A Type of Wearing Surface
1 digit 108B Type of Membrane
1 digit 108C Deck Protection
NBI Elements > ITEM 108A - Type of Wearing Surface
Code Description
1 Monolithic Concrete (concurrently placed with structural deck)
2 Integral Concrete (separate non-modified layer of concrete added to structural deck)
3 Latex Concrete or similar additive
4 Low slump Concrete
5 Epoxy Overlay
6 Bituminous
7 Wood or Timber
8 Gravel
9 Other
0 None (no additional concrete thickness or wearing surface is included in the bridge deck)
N Not applicable (applies only to structures with no deck)
99 Miscoded data
NBI Elements > ITEM 108B - Type of Membrane
Code Description
1 Built-up
2 Preformed Fabric
3 Epoxy
8 Unknown
9 Other
0 None
N Not applicable (applies only to structures with no deck)
99 Miscoded data
NBI Elements > ITEM 108C - Deck Protection
Code Description
1 Epoxy Coated Reinforcing
2 Galvanized Reinforcing
3 Other Coated Reinforcing
4 Cathodic Protected
6 Polymer Impregnated
7 Internally Sealed
8 Unknown
9 Other
0 None
N Not applicable (applies only to structures with no deck)
99 Miscoded data
NBI Elements > ITEM 109 - Average Daily Truck Traffic
The percentage that shows the percentage of Item 29 - Average Daily Traffic that is truck Trafic.
NBI Elements > ITEM 110 - Designated National Network
Code Description
0 The inventory route is not part of the national network for trucks.
1 The inventory route is part of the national network for trucks.
99 Miscoded data
NBI Elements > ITEM 111 - Pier or Abutment Protection
Code Description
1 Navigation protection not required
2 In place and functioning
3 In place but in a deteriorated condition
4 In place but re-evaluation of design suggested
5 None present but re-evaluation suggested
99 Miscoded data
NBI Elements > ITEM 112 - NBIS Bridge Length
Does this structure meet or exceed the minimum length specified to be
designated as a bridge for National Bridge Inspection Standards purposes?
Code Description
Y Yes
N No
99 Miscoded data
NBI Elements > ITEM 113 - Scour Critical Bridges
Code Description
N Bridge not over waterway.
U Bridge with "unknown" foundation that has not been evaluated for scour. Until risk can be
determined, a plan of action should be developed and implemented to reduce the risk to
users from abridge failure during and immediately after a flood event (see HEC 23).
T Bridge over "tidal" waters that has not been evaluated for scour, but considered low risk.
Bridge will be monitored with regular inspection cycle and with appropriate underwater
inspections until an evaluation is performed ("Unknown" foundations in "tidal" waters
should be coded U.)
9 Bridge foundations (including piles) on dry land well above flood water elevations.
8 Bridge foundations determined to be stable for the assessed or calculated scour condition.
Scour is determined to be above top of footing (Example A) by assessment (i.e., bridge
foundations are on rock formations that have been determined to resist scour within the
service life of the bridge4), by calculation or by installation of properly designed
countermeasures (see HEC 23).
7 Countermeasures have been installed to mitigate an existing problem with scour and to
reduce the risk of bridge failure during a flood event. Instructions contained in a plan
of action have been implemented to reduce the risk to users from a bridge failure during
or immediately after a flood event.
6 Scour calculation/evaluation has not been made. (Use only to describe case where bridge
has not yet been evaluated for scour potential.)
5 Bridge foundations determined to be stable for assessed or calculated scour condition.
Scour is determined to be within the limits of footing or piles (Example B) by assessment
(i.e.,bridge foundations are on rock formations that have been determined to resist scour
within the service life of the bridge), by calculations or by installation of properly
designed countermeasures (see HEC 23).
4 Bridge foundations determined to be stable for assessed or calculated scour conditions;
field review indicates action is required to protect exposed foundations (see HEC 23).
3 Bridge is scour critical; bridge foundations determined to be unstable for assessed or
calculated scour conditions:
- Scour within limits of footing or piles. (Example B)
- Scour below spread-footing base or pile tips. (Example C)
2 Bridge is scour critical; field review indicates that extensive scour has occurred at
bridge foundations, which are determined to be unstable by:
- a comparison of calculated scour and observed scour during the bridge inspection, or
- an engineering evaluation of the observed scour condition reported by the bridge
inspector in Item 60.
1 Bridge is scour critical; field review indicates that failure of piers/abutments is
imminent. Bridge is closed to traffic. Failure is imminent based on:
- a comparison of calculated and observed scour during the bridge inspection, or
- an engineering evaluation of the observed scour condition reported by the bridge
inspector in Item 60.
0 Bridge is scour critical. Bridge has failed and is closed to traffic.
99 Miscoded data
NBI Elements > ITEM 114 - Future Average Daily Traffic
The forecasted average daily traffic(ADT) for the inventory route identfied in Item 5.
NBI Elements > ITEM 115 - Year of Future Average Daily Traffic
Year represented by the future ADT in Item 114.
NBI Elements > ITEM 116 - Minimum Navigation Vertical Clearance, Vertical Lift Bridge
The minimum vertical clearance imposed at the site as measured above a datum that is specified on a navigation
permit issued by a control agency. Measured in meters.
NBI Elements > Deck area
This is Deck width( ITEM 52 ) times Structure length( ITEM 49 ) or ITEM_52 x ITEM_49.
NBI Elements > FIPS
The first 2 digits are the Federal Information Processing Standards (FIPS) code for Item 1, and the last 3 digits are the
code for Item 3.
NBI Elements > Status
Code Description
0 Not defecient
1 Structurally defecient
2 Functionally obsolete
N Not applicable
NBI Elements > Sufficiency rating
The sufficiency is a method of evaluating highway bridge data by calculating four separate factors to obtain
a numeric value which is indicative of bridge sufficiency to remain in service. The result of this method is
a percentage in which 100 percent would represent a entirely sufficient bridge and zero percent would represent
an entirely insufficient or deficient bridge.
NBI Elements > Structurally defecient(SD) & Functionally obsolete(FO) Criteria
Below are the definitions for SD criteria and FO criteria in this application. It must be noted
that, based on the criteria used, a bridge could be both structurally deficient and functionally obsolete.
The status field however provides the option of running a query in which a bridge designated as functionally obsolete is
not structurally deficient. In other words functionally obsolete bridges are exclusive of structurally deficient bridges.
Also, the status field definition of bridge deficiencies is limited only to those bridges which are 10 years or
older and are more than 20 feet in length.
Definition of SD criteria
SD(Structurally deficient) criteria are defined as bridges that meet at least one of the following qualifications:
1. ITEM 58 coded 0, 1, 2, 3 or 4; or
2. ITEM 59 coded 0, 1, 2, 3 or 4; or
3. ITEM 60 coded 0, 1, 2, 3 or 4; or
4. ITEM 62 coded 0, 1, 2, 3 or 4; and the last two digits of ITEM 43 are coded 19; or
5. ITEM 67 coded 0, 1 or 2; or
6. ITEM 71 coded 0, 1 or 2 and the last digit of ITEM 42 coded 0, 5, 6, 7, 8 or 9.
Definition of FO criteria
FO(Functionally Obsolete) criteria are defined as bridges that meet at least one of the following qualifications:
1. ITEM 68 coded 0, 1, 2 or 3; or
2. ITEM 69 coded 0, 1, 2 or 3 and the last digit of ITEM 42 coded 0, 1, 2, 4, 6, 7 or 8; or
3. ITEM 72 coded 0, 1, 2 or 3; or
4. ITEM 67 coded 3; or
5. ITEM 71 coded 3 and the last digit of ITEM 42 coded 0, 5, 6, 7, 8 or 9.