Bridge Inspection Practices (2007) / Chapter Skim
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Appendix F - Details for Inspection Types and Intervals
Appendix F - Details for Inspection Types and Intervals
Pages 145-169
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From page 146... ...
. Note: Not all inspection intervals are shown.
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From page 147... ...
. Note: Not all inspection intervals are shown.
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From page 148... ...
is 4 or greater Cross-channel profile Component 120 months Channel condition (61) > 7 Cross-channel profile Component 120 months Scour SmartFlag not on Timber member boring report Component Immediate Hollow sound, borer or beetle activity, bulging, splits, cracks noted during routine inspection Timber member boring report Component 96 months Structure located west of the Coast Range and in service longer than 20 years Timber member boring report Component 120 months Structure located in western Oregon and in service longer than 25 years Oregon Timber member boring report Component 144 months Structure located east of the Cascades and in service longer than 30 years Pennsylvania Routine, close-up, hands-on Component 72 months Areas without hands-on in other routine inspections, as noted in inspection report Tennessee Cursory -- substructure Component 24 months Substructure in shallow water TABLE F4 PERIODIC TASKS IN ROUTINE INSPECTION
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From page 149... ...
UBIV = under bridge inspection vehicle; NBIS = National Bridge Inspection Standards. DOT Inspection Scope Interval Notes TABLE F5 ACCESS FOR ROUTINE INSPECTION
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From page 152... ...
152 DOT Name Location on Component Notes Routine Most routine inspections are hands-on Alabama Special D -- Pin and hanger details Close-up inspection of pin and hanger Alaska Routine Extent of hands-on varies as needed Arizona Hands-on Locations identified in report Extent of hands-on varies as needed Arkansas Hands-on Locations identified in report and in database Extent of hands-on varies as needed California Hands-on Electronic notes; not searchable Extent of hands-on varies as needed Hands-on Locations identified in report; excluded areas also noted Extent of hands-on varies as needed Box beams -- Curved Box beams -- Bridges with one or two box beams Tension members of trusses Welded connections for lateral bracing All nonredundant members Rusted areas of members All bearings Metal deck connections Welds in tension Repaired welds Connecticut 100% hands-on 100% hands-on 100% hands-on 100% hands-on 100% hands-on 100% hands-on 100% hands-on 100% hands-on 100% hands-on 100% hands-on 100% hands-on Fatigue-prone welds Delaware Hands-on Locations identified in report Extent of hands-on varies as needed Hands-on Some post-tensioned structures; every cycle Hands-on Bearings, if accessible Post-tensioned box girders Every square foot must be viewed; use UBIV as required. Hands-on At least some sounding of concrete At least some probing of timber Hands-on Eastern Federal Lands Hands-on Clean and inspect representative area of bearings Florida Locations identified in report Extent of hands-on varies as needed Idaho Hands-on Locations identified in report and in database Extent of hands-on varies as needed Iowa Hands-on Locations identified in report and in database Extent of hands-on varies as needed Kentucky Hands-on Locations identified in report and in database Extent of hands-on varies as needed Maine Hands-on Locations identified in electronic report, not database Extent of hands-on varies as needed Maryland Hands-on Locations identified in report and in database Extent of hands-on varies as needed Michigan Hands-on Locations identified in web-based report Extent of hands-on varies as needed Missouri Hands-on Locations identified in report and in database Extent of hands-on varies as needed (continued )
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From page 153... ...
for fracture-critical details (pin and hangers, etc.) Critical sections of controlling members on posted bridges Scour-critical substructure units End regions of steel girders or beams under deck joint Cantilever portions of concrete piers or bents in fair or lesser condition TABLE F7 (Continued)
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From page 154... ...
154 DOT Name Location on Component Notes Routine inspections are hands-on notes UBIV = under bridge inspection vehicle; ADTT = average daily truck traffic. Rhode Island Hands-on All routine inspections are hands-on Tennessee Hands-on Texas Hands-on Locations identified in report Extent of hands-on varies as needed Vermont Hands-on Locations identified in report Extent of hands-on varies as needed Hands-on Locations identified in report Extent of hands-on varies as needed AASHTO fatigue categories D or worse and ADTT 500 or more Virginia Fatigue prone AASHTO fatigue categories D or worse and Interstate route Washington Hands-on Locations identified in report and in electronic notes Most routine inspection is hands-on; extent of hands-on varies as needed West Virginia Hands-on Locations identified in report and in electronic Extent of hands-on varies as needed Locations identified in report and in database Hands-on Hands-on Locations identified in report and in database Ends of prestressed concrete beams at continuity diaphragms Precast concrete bridge parapets TABLE F7 (Continued)
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From page 155... ...
Entire Culverts measure water velocity upstream, downstream, and hydraulic opening In-depth pin/hanger Component 24 months Ultrasonic inspection of pins and hangers for suspended spans Florida Storm event -- Level 3 In-depth inspection based on findings of Level 1 or 2 inspection 25-year-old bridge Entire Do "Detail" inspection Michigan Fatigue-prone details Component 36 months Redundant bridges having fatigue-prone details New Jersey Fracture critical Entire 48 months Alternate inspection cycles (continued )
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From page 156... ...
Collect electrical potentials, chloride contents, amount of section loss in steel reinforcement In-depth -- Concrete segmental bridge Component 120 months Concrete segmental bridge Inspection for corrosion of posttensioning system and for longitudinal cracking In-depth -- Electroslag welds Component 120 months Bridge has electroslag welds Nondestructive testing for fatigue cracks in the welds In-depth -- Other special details Component 120 months Other details that warrant special inspection In-depth -- Pin and hanger Component 120 months Redundant pin and hanger assemblies In-depth -- stringer/floorbeam connections Component 120 months Stringer/floorbeam connections Oregon Movable bridge Component 72 months In-depth inspection of operational mechanism In-depth -- Fracture critical Entire 120 months Fracture-critical member in fair or lesser condition Span 150 ft In-depth -- Fracture critical 180 months Fracture-critical member in good condition In-depth -- Redundant, not fracture critical 180 months Span >500 ft Pennsylvania In-depth -- Redundant, not fracture critical 120 months Redundant, non-fracture-critical bridges Span >500 ft and superstructure in poor or lesser condition Ferry -- Vehicle transfer spans Component 24 months Ferry terminal -- Other structures/areas Component 24 months Movable bridge equipment Component 72 months In-depth for electrical and mechanical equipment Washington Underwater -- In-depth Component (specific) As needed Detailed inspection of specific portions; may include nondestructive testing Wisconsin In-depth Entire 72 months DOT Name Scope Interval Notes TABLE F8 (Continued)
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From page 157... ...
No diver. Channel cross section and scour evaluation Underwater Type 2 Dive inspection where wading/probing not possible and water at least 4 ft deep Cleaning: 100% Level I, 10% Level II Underwater Type 3 Dive inspection, in-depth for prior evidence of distress or scour Cleaning: 100% Level I, >10% Level II New Jersey Underwater Type 4 Dive inspection to prepare for replacement, rehabilitation, or priority repairs Cleaning: Level II Dive Water depth >0.9 m, water current >0.6 m/s, and chest waders not adequate 60 months Scour rating 4 or higher.
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From page 158... ...
May identify portions and recommend in-depth inspection UW probe/visual 24 months Inspection from surface of water UW survey 24 months Streambed profile in vicinity of bridge Wisconsin UW dive 60 months Dive inspection DOT Name Interval Notes TABLE F9 (Continued)
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From page 159... ...
159 DOT Name Scope Interval Notes Alabama Fracture-critical details Component 24 months Connecticut Fracture critical -- secondary roads Rotating 25% of details receive hands-on Bridges not on Interstate or other limitedaccess highway Fracture critical Component 24 months Fracture-susceptible bridges Fracture critical w/NDE Component 120 months Includes use of nondestructive testing Eastern Federal Lands UBIV fracture critical Component Iowa Fatigue Component 24 months Fracture-critical bridges, bridges with arrested cracks Minnesota Fracture critical 12 months Comprehensive inspection fracture-critical Missouri Most fracture-critical member Montana Fracture critical Component 24 months Fracture critical Component 24 months Hands-on for vulnerable areas and details New Jersey Fracture critical -- In-depth Entire 48 month In-depth for alternate inspection cycles North Carolina Fracture critical Rhode Island Fracture critical 12 months 12 months Base metal is ASTM A7, A8, A94, A242, A440, A514, or A517 steel 24 months Age of structure > 30 years ADTT > 1000 Oregon Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Component Component Component Component Component Component Component Component Component Component Component Component Component Age of structure < 30 years ADTT < 1000 Base metal has low values of toughness in field situations; similar to A514 or A517 Nonredundant riveted or bolted members in tension Bending with no welding present 48 months Detail vulnerable to fatigue or collision damage Nonredundant riveted or bolted members with tack welding present Nonredundant welded members in bending Nonredundant welded members in direct tension Pin and hanger assembly -- Perform an initial UT of the pin and hangers and follow-up at least every 4 years E or E' detail -- Perform an initial UT of the detail and follow up at least every 4 years Age of structure > 30 years Rolled members with no welds present 72 months (continued )
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From page 160... ...
160 DOT Name Scope Interval Notes Level 2 -- Fracture-critical inspection Level 2 -- Fracture-critical inspection Component Component ADTT > 1,000 Rolled members with no welds present Age of structure < 30 years Rolled members with no welds present 120 m onths ADTT < 1,000 Rolled members with no welds present 120 m onths Fracture-critical memb er in fair or lesser condition Span 150 ft Pennsylvania In-depth -- Fracture critical Entire 180 m onths Fracture-critical memb er in good condition Virginia Fracture critical Component 12 m onths Washington Fracture critical Component 24 m onths Wisconsin Fracture critical Component 72 months UBIV = under bridge inspection vehicle; UT = ultrasonic testing ; NDE = nondestructive evaluation; ADTT = average daily truck traffic. TABLE F10 (Continued)
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From page 161... ...
These must receive special inspections Inspection team will include specialists, as needed Nevada New Jersey Yes Open-deck railroad bridges -- Special attention to condition of ties Ultrasonic inspections Movable bridges New Mexico New York No Require all inspectors to handle any bridge Inventory indicates need for special equipment during inspection North Carolina No Require all inspectors to handle any bridge North Dakota Yes Training for segmental box bridges Ohio Yes Major bridges identified by span length and structure type Inspectors must demonstrate adequate experience In-depth inspection may require riggers, divers, or other personnel with special skills Oklahoma Yes Snooper inspection of "Long and Tall" bridges that are not fracture critical Monitoring pier movement with an electronic distance measuring device Oregon Yes Special expertise or equipment may be needed for: Movable bridge Suspension or cable-stayed bridge Tall bridge (continued )
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From page 162... ...
Pennsylvania Yes Prestressed concrete segmental bridges More experienced team leaders are used for more complex inspections Critical elements of complex structures may be inspected separately for use of special equipment or personnel Consultants hired for complex inspection by central office Rhode Island Yes One concrete segmental bridge One tied-arch bridge South Dakota No No complex bridges identified Tennessee No Movable, suspension, or cable-stayed bridges Other bridges with unusual characteristics No special qualifications for personnel TABLE F11 (Continued)
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From page 163... ...
163 DOT Name Scope Interval Note Alabama Special C -- Suspension and movable bridges Entire Movable bridge 12 months Poor condition Florida Movable portion Operation 12 months Maryland Drawbridge Equipment Team has electrical engineer and mechanical engineer Michigan Movable equipment, routine Equipment 72 months Movable bridge equipment Movable Bridge -- Type I Equipment In-depth electrical, mechanical equipment inspection Movable Bridge -- Type II Equipment Medium-depth electrical, mechanical equipment inspection New Jersey Movable Bridge -- Type III Equipment Visually monitor operation of electrical, mechanical equipment North Carolina Movable span inspections Oregon Movable bridge Entire 12 months Cursory inspection for operation Virginia Movable bridge Special team having an electrical engineer, a bridge safety engineer, and a mechanical engineer Movable bridge operation Operation 1 month Trial opening of span Special feature -- Movable 12 months Inspector has special training or experience Washington Movable bridge equipment Equipment 72 months In-depth for electrical and mechanical equipment Wisconsin Movable bridge 12 months TABLE F12 ROUTINE INSPECTIONS OF MOVABLE BRIDGES
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From page 164... ...
Temporary supports for beams Load posted for operating rating Superstructure condition rating 3 or less New Jersey Interim inspection Component 12 months Substructure condition rating 3 or less 12 months Scour rating 1 or 2. Active structural flag for scour Fathometer survey, channel cross section Component 24 months Scour rating 3 General recommendation 3, assigned by inspector Condition rating weighted average 3, computed by NYSDOT data system Inactive red flag or active yellow flag Posted bridge Poor condition New York Interim (Type 2)
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From page 165... ...
Unscheduled inspection DOT Inspection Scope Interval Notes Unrepaired critical findings Interim (Type 2) Interim (Type 2)
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From page 166... ...
TABLE F15 SPECIAL INSPECTIONS DOT Inspection Interval Notes Connecticut Routine -- Bridges 48 months In service four years Had in-depth inspection Condition ratings 6 or better HS 30 inventory Single span <100 ft span Less than 75 years old 14 ft vertical clearance ADT < 125,000 ADTT < 10% Eastern Federal Lands Bridges 48 months Main elements condition rating >5 Montana NBI/element level inspection 48 months Prestressed structures MDT design standards Length < 100 ft Known good condition Oregon Routine -- Culvert 48 months Culvert (62) condition 6 or better Element state 100% 1 or 2 ADT = average daily traffic; ADTT = average daily truck traffic; MDT = Montana Department of Transportation.
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From page 167... ...
NBI procedures, but not reported to FHWA Montana Minor bridge Spans down to 8 ft on national and state highway systems, or on transporter erector routes Minor culverts Inspected as funds allow Noise wall Noise reduction walls New Jersey Railroad bridge Open deck railroad bridges. Inspect condition of ties as hazard to road below New York Sign structure Overhead sign structure; rating scale similar to bridges Adjacent structure All structures, over or adjacent to public roads, that in failure would cause immediate danger to traveling public Minor bridge Minor structures; spans down to 6 ft Oregon Tunnel Tunnels Conveyor belt Conveyor belts High-mast light High-mast lighting Highway environs -- H 24 months Non-bridge over highway.
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From page 168... ...
In-depth inspection Ferry terminal equipment 12 months Ferry terminal equipment. Electrical systems, mechanical systems, hoists Ferry terminal soundings 12 months Soundings at vehicle transfer spans of ferry terminals Highway lid 60 months Bridge span < 20 ft, on STRAHNET highway Bridge span < 20 ft, operating rating less than HS 10 Bridge span < 20 ft, vertical clearance < 18 ft Single steel or concrete spans 6 ft to 20 ft Steel corrugated pipes, spans 8 ft to 20 ft Minor bridge 72 months Timber spans 4 ft to 20 ft Multiple pipe 72 months Multiple pipes out to 10 ft to 20 ft Multiple span 72 months Multiple spans 8 ft to 20 ft Overhead structures Safety inspection of structures crossing state-owned facilities Pedestrian bridge 60 months Pedestrian bridge Private bridge 60 months Private bridges over public highways Sign structure Sign bridges Washington Tunnel 24 months Tunnels NBIS = National Bridge Inspection Standards; STRAHNET = Strategic Highway Network.
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