National Academies Press: OpenBook

Bridge Inspection Practices (2007)

Chapter: Chapter Two - Transportation Agencies

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Suggested Citation:"Chapter Two - Transportation Agencies." National Academies of Sciences, Engineering, and Medicine. 2007. Bridge Inspection Practices. Washington, DC: The National Academies Press. doi: 10.17226/14127.
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Suggested Citation:"Chapter Two - Transportation Agencies." National Academies of Sciences, Engineering, and Medicine. 2007. Bridge Inspection Practices. Washington, DC: The National Academies Press. doi: 10.17226/14127.
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Suggested Citation:"Chapter Two - Transportation Agencies." National Academies of Sciences, Engineering, and Medicine. 2007. Bridge Inspection Practices. Washington, DC: The National Academies Press. doi: 10.17226/14127.
×
Page 9
Page 10
Suggested Citation:"Chapter Two - Transportation Agencies." National Academies of Sciences, Engineering, and Medicine. 2007. Bridge Inspection Practices. Washington, DC: The National Academies Press. doi: 10.17226/14127.
×
Page 10
Page 11
Suggested Citation:"Chapter Two - Transportation Agencies." National Academies of Sciences, Engineering, and Medicine. 2007. Bridge Inspection Practices. Washington, DC: The National Academies Press. doi: 10.17226/14127.
×
Page 11
Page 12
Suggested Citation:"Chapter Two - Transportation Agencies." National Academies of Sciences, Engineering, and Medicine. 2007. Bridge Inspection Practices. Washington, DC: The National Academies Press. doi: 10.17226/14127.
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7U.S. INSPECTION INVENTORY U.S. federal regulations require the periodic inspection of bridges on public roads with a span of greater than 20 ft (1). State DOTs may inspect other highway structures such as sign bridges, high mast lights, tunnels, and retaining walls, as well as minor bridges with span of 20 ft or less. Structures such as pedestrian bridges and railroad bridges that cross public roads are also inspected, either directly by the DOT or bridge owners. The counts of National Bridge Inventory (NBI)-eligible structures among U.S. states range from fewer than 800 in Rhode Island to more than 49,000 in Texas (Table 5). These include bridges owned by the state government, local gov- ernments, tollway authorities, and others. Although the re- sponsibility for compliance with federal regulations at all bridges is imposed on the state government and by extension the state DOT, inspection of bridges may be done by bridge owners, subject to review and approval by the state DOT. The set of NBI-eligible structures includes approximately 471,000 bridges and 125,000 culverts. Of these, 499,000 are water crossings, 38,000 require underwater inspection, 22,000 are fracture-critical, and 84,000 are posted for load capacity (see Table 5). ADMINISTRATIVE LEVELS U.S. road agencies exist at national, state, and local levels. At the national level, the FHWA is concerned with the infra- structure of public roads throughout the nation. The FHWA executes the bridge inspection programs for many federally owned bridges on public roads and regulates the inspection of public roads bridges owned by others. U.S. state transporta- tion departments execute bridge inspection programs for state-owned bridges and variously execute, regulate, or re- view inspection programs for bridges owned by others within the state. Local governments are among these other owners. Inspection of local governments bridges are performed by local agency staff, by consultants hired by local road agen- cies, or by state DOT staff. Federal regulations address bridge inspection population, inspection intervals, inspection methods, inspection person- nel, and inspection reporting. Federal requirements are presented primarily in the Code of Federal Regulations (1) and, by reference, in FHWA guides and manuals (3,4), AASHTO manuals (5–7), and National Highway Institute (NHI) courses. State DOTs, acting within the limits of federal regulation, develop additional requirements and provide more detailed statements of inspection program requirements. ROAD AGENCIES IN OTHER NATIONS Denmark—Danish Road Directorate The Danish Road Directorate administers 4000 km of road- ways; approximately 5% of the total public road network in Denmark (see Table 6). The Directorate’s responsibilities in- clude bridges, tunnels, retaining walls, noise barriers, sign structures, and ferry berths. In 2006, Denmark had national roads, regional roads, and local roads, and a corresponding three levels of road agen- cies. A reorganization that became effective in 2007 elimi- nated county agencies and reduced the number of municipal agencies (see Table 7). Some roads and major bridges are conceded, and some crossings, including the Great Belt and the Oresund, are private roads. The Road Directorate is responsible for planning, creation of standards for road design and construction, and for inspec- tions of structures. The Directorate prepares a guide to inspec- tion of bridges (8), which is followed by the Directorate and by local agencies. Local agencies frequently hire consultants for bridge inspection, and inspection data for local bridges are usually reported to the Directorate, although this is not manda- tory. Local agency bridges are designed, inspected, and rated in conformance with Directorate standards. Finland—Finnish Road Administration The Finnish Road Administration (Finnra) manages 78 000 km of roads, 11,191 bridges, and 2,935 culverts. Finnra oversees contract work, with design, construction, maintenance, and most inspections performed by contractors. Finnra sets national standards for bridges, offers expert guidance to regional and local road agencies, and addresses all issues that must be coordinated at the national level. Finnra’s guides and handbooks are followed by local road agencies, by other Finnish agencies such as the forestry CHAPTER TWO TRANSPORTATION AGENCIES

8Structures Owner Special Inspection Load Postings Water Crossings DOT Alabama Alaska Arizona Arkansas California Colorado Connecticut 8 DC Delaware Florida Georgia Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Ohio Oklahoma Oregon Pennsylvania Puerto Rico Rhode Island South Carolina South Dakota Tennessee Texas Utah Vermont Virginia Washington West Virginia Wisconsin Wyoming Bridges 9,921 1,125 3,361 9,690 20,757 6,617 3,569 244 649 9,352 9,081 948 3,962 21,664 16,832 21,270 17,834 10,672 10,995 2,034 3,914 4,624 9,488 7,261 13,647 19,239 4,725 12,510 952 2,127 6,035 2,164 15,665 12,725 3,641 26,296 16,722 6,937 20,613 1,816 721 8,120 4,811 11,388 31,408 2,302 2,530 10,275 7,395 6,417 11,765 2,609 Culverts 5,784 53 3,849 2,792 3,274 1,661 599 2 203 2,189 5,444 158 110 4,142 1,442 3,583 7,682 2,851 2,356 336 1,170 298 1,399 5,773 3,258 4,645 204 2,947 682 244 410 1,672 1,677 4,788 837 1,770 6,665 314 1,694 327 28 1,084 1,150 8,381 17,818 526 173 2,974 250 504 1,926 424 State 5,602 756 4,469 7,084 11,900 3,442 2,775 211 812 5,295 6,499 704 1,269 7,513 5,132 3,972 4,829 8,784 7,794 1,936 2,504 2,816 4,408 3,571 5,537 10,134 2,449 3,471 956 1,289 2,370 2,933 7,424 16,531 1,111 8,855 6,759 2,661 14,812 1,812 588 8,326 1,811 8,038 32,086 1,706 1,077 11,696 3,080 6,628 4,869 1,938 Local 9,925 123 2,268 5,239 11,342 4,534 1,235 0 7 5,477 7,767 370 1,620 17,613 12,664 20,665 20,090 4,624 5,241 208 2,174 1,536 6,368 9,245 10,879 13,637 1,938 11,795 613 861 2,532 699 8,512 712 3,298 18,448 15,767 3,918 6,004 322 138 818 4,021 11,330 16,467 967 1,597 1,086 3,869 108 8,682 839 Other 178 299 473 159 789 302 158 35 33 769 259 32 1,183 680 478 216 597 115 316 226 406 570 111 218 489 113 542 191 65 221 1,543 204 1,406 270 69 763 861 672 1,491 9 23 60 129 401 673 155 29 467 696 185 140 256 Fracture Critical 260 103 65 347 1,007 207 169 13 29 339 82 10 173 550 523 1,660 1,109 349 142 45 285 329 105 248 244 1,589 310 1,289 34 144 652 53 1,777 140 239 1,099 754 347 1,896 22 35 65 228 271 624 62 161 344 364 563 116 97 Under- water 945 175 12 7,536 638 75 309 13 77 3,950 2,170 102 306 1,293 710 144 201 2,147 1,198 371 421 756 353 338 304 174 499 95 122 137 708 7 804 2,142 38 290 71 676 3,881 30 89 241 112 543 796 78 53 697 315 256 276 61 Other Special 380 12 43 707 80 61 289 2 21 578 94 19 71 271 905 939 572 84 7 14 135 448 187 187 1,715 318 24 50 25 53 391 32 4 27 37 29 1,129 42 1,981 40 97 322 26 46 108 46 41 134 170 337 12 13 Bridges 2,982 273 201 1,836 803 672 106 29 7 988 2,050 146 593 1,128 1,923 5,298 9,803 1,346 2,124 99 356 433 1,253 350 3,828 5,656 648 5,246 25 222 291 180 1,145 4,427 1,040 2,434 5,818 796 2,618 198 70 601 1,333 1,258 3,602 211 125 1,269 802 314 378 448 Culverts 47 2 26 13 25 31 1 2 31 15 4 4 8 114 20 2,861 51 11 1 26 9 51 76 151 86 8 0 2 8 6 4 19 9 4 17 144 30 48 13 1 26 54 32 86 8 1 18 17 3 6 27 Bridges 8,342 1,042 2,242 8,822 12,699 5,383 1,779 91 407 6,302 6,843 762 3,485 18,068 14,706 19,722 16,102 9,284 10,909 1,557 2,346 2,194 6,485 5,400 12,269 16,652 3,930 11,849 365 1,556 3,235 1,560 10,425 9,802 3,273 21,240 14,748 5,840 15,595 1,322 321 6,845 4,313 8,775 23,501 1,387 2,178 7,341 5,574 5,755 9,088 1,758 Culverts 5,783 49 3,844 2,791 3,164 1,621 595 2 203 2,176 5,430 157 109 4,131 1,428 3,582 7,628 2,781 2,355 331 1,161 289 1,391 5,593 3,252 4,633 197 2,944 668 233 405 1,628 1,651 4,780 829 1,739 6,633 313 1,653 322 28 1,075 1,144 8,376 17,815 503 124 2,969 238 474 1,918 422 Source: National Bridge Inventory Data (2). TABLE 5 U.S. NATIONAL BRIDGE INVENTORY STRUCTURES National Directorate Local Agencies Roads (route miles) 4000 km 70 000 km Bridges* 3,500 7,000 *Approximate number. Prior to 2006 Current (2007) County Road Agencies 14 0 Municipal Road Agencies 273 99 TABLE 6 ROADS AND BRIDGES IN DENMARK TABLE 7 ROAD AGENCIES IN DENMARK

9administration, and by private bridge owners. Local road agencies (primarily municipal governments) can store their bridge information in Finnra’s registry if the local user is cer- tified for the registry. Documents prepared by Finnra include guidelines and pol- icy for bridge maintenance, rehabilitation, and repair operation; guidelines for bridge inspection; a bridge inspec- tion manual; and a bridge repair manual [SILKO Guidelines, Siltojen Korjausohjeet (Bridge Repair Guidelines)]. France—French National Road Directorate French road authorities exist at three levels: national, de- partmental (similar to U.S. states), and local (cities, towns, and villages). The French National Road Directorate, an agency within the French Ministry of Equipment (Ministère de l’Équipement, des Transports, de l’Aménagement du territoire, du Tourisme et de la Mer (Ministry for Infra- structure, Transport, Spatial Planning, Tourism, and the Sea), provides funding to national road agencies acting in the departments (states) and establishes national policies for road transport. The Directorate develops and operates the bridge management system. Departmental agencies [Direction Départementale de l’Equipement (DDE), an agency of the Ministry of Equipment] do repairs of bridges and conduct specialized studies and investigations as needed. Local agencies, called subdivisions, each guided by its departmental agency, do routine bridge inspection and maintenance. In France, the Instruction Technique pour la Surveillance et l’Entretien des Ouvrages d’Art (ITSEOA) (9) establishes procedures for inspection of most roadway infrastructure including bridges, tunnels, culverts, retaining walls, and embankments. The first part of the ITSEOA addresses admin- istrative issues. The second part consists of 30 documents addressing methods and techniques for particular materials and structures. Condition assessment is further guided by the Image de la Qualité des Ouvrages d’Art (IQOA) (10), which presents standard classifications for each kind of deterioration and dam- age encountered on some 25 types of structures. Two substantial reorganizations of French road agencies have occurred since the 1980s. Before 1982, the Ministry of Equipment controlled 105,000 bridges. Between 1982 and 2006, the ministry had direct control of 23,000 bridges and controlled the activities of six private companies that man- aged conceded motorways. There are 7,000 bridges along these motorways. In 2006, further decentralization reduced the Directorate’s inventory to fewer than 15,000 bridges. Roadway concessionaires have consolidated, and there are now three large corporations managing most conceded roads. Overall, maintenance responsibilities at most bridges are del- egated to private companies. There are 11 interdepartmental road agencies that have direct control of inspections, maintenance, repairs, and re- placements of bridges. Funds for these activities come from the national government, and decisions on repairs and replace- ments are subject to review and approval by the national road directorate. National funds for bridge repairs are allocated to interde- partmental road agencies through five general supervisors. The supervisors belong to the General Bridge Inspection Service and each supervisor is charged with a geographic region in France. General supervisors control DDE activities that affect bridges. Local road agencies include approximately 100 Conseil Général, and more than 38,000 towns and villages. Local road agencies are assisted by the Assistance Technique fournie par l’etat pour des raisons de Solidarité et de l’Amé- nagement du Territoire (ATESAT), a program of the Min- istry of Equipment, to ensure the safety of roadways. Technical organizations involved in bridge engineering and road operations include: SETRA (Service d’Etudes Techniques des Routes et Autoroutes)—reviews proposed repair projects and operates LAGORA, the French bridge management system. CETE (Centre d’Etudes Techniques de l’Equipement)—a group of eight regional centers providing technical advice to local road agencies and assisting in bridge investigations and planning for repair projects. LCPC (Laboratoire Central des Ponts et Chaussées)—the central (national) laboratory performing bridge research and providing expert technical advice on bridges. LRPC (Laboratoire Régional des Ponts et Chaussées)—a group of 17 regional laboratories engaged in detailed inspec- tion, testing, instrumentation, and diagnosis for bridges and structures. CETU (Centre d’Etudes des Tunnels)—performs detailed inspection, testing, and studies of tunnels. Road concessionaries are required to adhere to the guides and standards of the French National Road Directorate; local government road agencies are not. In practice, most local agencies do follow national standards, and it is the policy of Interior Ministry (Ministère de l’Intérieur, responsible for departments, towns, and cities) to advise local governments on their bridge inspections. Germany—German Federal Roads German federal roads are administered by the Bundesminis- terium für Verkehr, Bau und Stadtentwicklung (BMVBS) (Federal Ministry of Transport, Building, and Urban Affairs). The ministry provides advice and technical support

10 to German states and to other federal agencies. States admin- ister inspections, control data in the bridge management sys- tem, and develop five-year plans for maintenance programs. There are approximately 120,000 bridges on all roads; of these, 37,000 are on federal highways and trunk roads, and 83,000 are on state, county, municipal, and rural routes. [A note on wording: Germany distinguishes federal roads from national roads. Two German states, Bavaria and Sax- ony, refer to their state roads as national roads.] German guides and standards for inspection of structures and for standardized reporting of condition include: • Inspection and Testing of Engineering Structures in Connection With Roads, DIN 1076, 1999 (11). • Recording and Assessment of Damages, Guideline RI- EBW-PRÜF, 2004 (12). • Structure Inventory, ASB, 2004 (13). These publications are revised and updated by working groups that have representatives from BMVBS, from Bundesanstalt für Strassenwesen (Bundesanstalt für Strassen- wesen is the Federal Highway Research Institute of BMVBS), and from some federal states. Deutsches Institut für Normung (DIN), the German Institute for Standardization, provides standards for a wide range of engineering and man- ufacturing activities. German federal standards for bridge inspection apply to states for inspection of bridges on federal roads. Inspections of bridges on state roads and bridges on county and munici- pal roads are not required to meet federal standards; how- ever, local agencies are strongly encouraged to do so. Norway—Norwegian Public Roads Administration The Norwegian Public Roads Administration (Statens veg- vesen) has a central office, 5 regions, and 30 districts. All construction and maintenance are done by contract. In each region there is one engineer responsible for bridges. This engineer is involved in all activities including bridge man- agement, inspection, maintenance, repair, strengthening, and construction. South Africa—South African National Roads Agency The South African National Department of Transport devel- ops policy, strategy, and high-level regulation for all modes of transport. The Department of Transport directs the operat- ing agencies. The operating agency for roads is the South African National Roads Agency Limited (SANRAL), which administers the national road system. SANRAL’s assets in roads, structures, and equipment are valued at 30 billion Rand (US$3.8 billion). In addition to SANRAL, there are nine provincial departments of transport and numerous municipal transport agencies. SANRAL is decentralized. Four regional branches admin- ister roads. SANRAL has a total staff complement of approx- imately 140 individuals. SANRAL outsources most road de- sign and construction work to private firms. Inspections are also out-sourced. Firms hired by SANRAL to provide inspection services are assigned a section of road and a set of bridges. On conceded roads, concessionaires arrange all inspections, using their own personnel or hiring consulting engineers. Based on inspection reports, repair needs are identified and prioritized. Design consultants, in- dependent of inspection consultants, are hired to make de- tailed evaluations of bridges and to prepare plans and speci- fications for repair projects. Through training consultants, SANRAL offers certifica- tion courses for bridge inspectors. The agency reviews inspection reports; however, it does not verify inspection findings directly, although the overlapping work of inspec- tion consultants and project development consultants yields such verification for some bridges. SANRAL produces a manual for bridge inspection and reporting and maintains standards for design and construc- tion. These standards apply to the national roads whether maintained by SANRAL or by concessionaires. The agency does not formulate national regulations. It does not direct inspection practices of provincial governments or local gov- ernments, nor does it receive inspection data or otherwise monitor the condition of bridges other than bridges on na- tional roads. Road agencies in each of South Africa’s nine provinces are autonomous and perform all inspection and maintenance of bridges on provincial roads. Provincial agencies often follow SANRAL standards for bridge design, inspection, and main- tenance, although this is not required. The provinces do not participate in the inspection or maintenance of national roads within their boundaries. Swedish Road Administration Vagverket, the Swedish Road Administration (SRA), has approximately 6,500 employees in 16 groups that include the head office; 2 support and development divisions; 7 regional offices; and groups for vehicle registrations, driver licensing, ferry operations, engineering consulting, construction and maintenance, and road sector training. Three groups are profit centers: construction and mainte- nance, consulting services, and ferry operations. Profit centers operate as subsidiary companies of SRA and compete with

11 Nation Structure Type Min. Inspection Size Denmark 2 m span Finland 2 m France 2 m Germany 2 m Norway 2.5 m South Africa 6 m Sweden (pre-1989) 3 m Sweden (today) 2 m United Kingdom Highway bridge 1.8 m Germany Noise barrier 2 m height Germany Tunnel 80 m length Finland Pipe bridge 2 m span TABLE 9 MINIMUM SIZE FOR INSPECTION—FOREIGN AGENCIES private contractors and engineering consultants for work in bridge design, construction, and maintenance. SRA’s con- struction and maintenance group holds 62% of SRA routine maintenance contracts. Work performed by SRA includes strategic management, planning of projects, specifications for bridge works, procurement of bridge works, and supervision of contract work. SRA performs about half of all bridge inspections, with other inspections done by consultants. Work by consultants and SRA profit centers include bridge design, maintenance and repair projects, bridge construction, and bridge inspections. SRA maintains guides and manuals for bridge design, con- struction, and inspection. These are mandatory only for SRA bridges. Sweden does not have national regulations for bridge inspection, but these may be developed in the near future. There are seven regional road agencies in Sweden. The agencies maintain bridges on regional roads and on national roads. SRA provides funding and sets standards for the inspection and maintenance for SRA bridges, although the work is executed through the regional road agencies. Municipal road agencies are autonomous, operate without SRA oversight, but usually adhere to SRA standards in bridge design, construction, and inspection. United Kingdom of Great Britain and Northern Ireland—United Kingdom Highways Agency The United Kingdom Highways Agency has a network of 9400 km of trunk roads that link population centers, ports, and key cross-border routes. The network has approxi- mately 10,000 bridges and 6,000 other structures (tunnels, retaining walls, and sign structures). There are approxi- mately 100,000 other bridges and structures that are the re- sponsibility of local authorities. In total, the United King- dom has approximately 155,000 bridges on roadways, waterways, and rails. The Highways Agency has a staff of 1,700 people involved in development of guides and specifications, and in contract administration. It develops policies for the entire life cycle of bridges including construction, inspection, maintenance, and improvement. The direct tasks of construction, maintenance, inspection, etc., are done by contractors under Highways Agency oversight. All Highways Agency bridge inspections are performed under contract. Increasingly, the agency relies on long-term contracts for the operation and maintenance of roads. It has assigned 14 areas to Maintenance Area Contracts (MACs). MACs are usually let for 7 years. The 14 maintenance areas are regional in extent, with exact boundaries adjusted to achieve viable work programs. MACs operate in accordance with Highways Agency standards. The Design Manual for Roads and Bridges (14) was created and is maintained by the Highways Agency. The manual’s provisions are mandatory for work on highways controlled by the Highways Agency. The Highways Agency works in association with trunk road authorities in Scotland, Wales, and Northern Ireland to produce requirements for the inspection and management of structures. Requirements are published as BD 62/94 and BD 63/94. These are not statutory instruments; instead, they are enforce- able as contract provisions. Interim Advice Note IAN 45 mod- ifies the requirements in BD 62/94 and BD 63/94. The revised BD62/BD63 will be supplemented by advice in a bridge in- spection manual, which will have a scope similar to the FHWA/NHI training manual for inspectors. Highways Agency standards apply only to Highways Agency bridges; however, many regional and local road agencies also follow agency standards. These agencies may include Highways Agency standards as contract clauses to Nation Structures Inspected Denmark Bridges Culverts Decks on piles Sign bridges Retaining walls Cable ducts Pipe ducts Sluices All structures of importance to the traffic network Finland Inspectors are mostly employees of consulting firms that inspect all varieties of civil structures and highway assets. Germany Bridges Culverts Sign structures Signal structures Tunnels Noise barriers Retaining walls High mast lights Sweden Bridges Culverts Retaining walls TABLE 8 STRUCTURES INSPECTED—FOREIGN AGENCIES

12 their consultants. All road agencies have a statutory Duty of Care. The use of Highways Agency standards is one method of demonstrating sufficient care. The management of the secondary and tertiary road net- work is complex. Responsibilities are shared among a variety of counties, boroughs, and cities. These local entities are autonomous and can set their own rules, but most adopt some or all of the standards produced by the Highways Agency. BRIDGE INSPECTION INVENTORY— FOREIGN AGENCIES Tables 8 and 9 list the structures and minimum sizes of struc- tures inspected by foreign road agencies. These include bridges, culverts, and retaining walls in all countries, and tunnels, pipe bridges, sign bridges, and noise barriers in most countries. Finland inspects all structural assets of importance to the highway network, including decks on piles, retaining walls, cable ducts, pipe ducts, culverts, and sluices.

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TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 375: Bridge Inspection Practices examines bridge inspection practices in the United States and selected foreign countries. The report explores inspection personnel (staff titles and functions, qualifications, training and certification, inspection teams, and the assignment of teams to bridges), inspection types (focus, methods, and frequency), and inspection quality control and quality assurance. The report also reviews the uses agencies make of information gathered from bridge inspections, what triggers repairs, and plans for future development of inspection programs.

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