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6The database system developed under this project is designed to be compatible with existing practices in bridge maintenance of U.S. Departments of Transportation (DOTs). To ensure compatibility, current practices in programs for bridge maintenance were reviewed. Common features in main- tenance work activities and work reporting were noted. These common features became the basis in formation of a national database for bridge maintenance work. The review exam- ined the type and scope of work activities in bridge main- tenance. The review produced a glossary of terms in bridge maintenance. Scope of Bridge Maintenance Bridge maintenance can be defined in terms of policy state- ments, lists of actions, budget status and the capabilities of DOTsâ maintenance data systems. DOTs recognize mainte- nance as distinct from new construction, replacement of struc- tures, and major rehabilitation of structures. Replacement or modification of portions of bridges may be maintenance if projects are small and have a short duration. Larger projects are construction, rather than maintenance. Emergency work, usu- ally in response to accidents or extreme events, is classified as maintenance and can entail significant, temporary modifica- tions to bridges. DOT Maintenance Actions Most DOTs recognize bridge components as objects of maintenance actions. Maintenance actions at most DOTs distinguish construction materials (repair steel versus repair concrete) and types of work (patch beam versus straighten beam). Some DOTs recognize separate maintenance actions for different types or forms of bridge component. Numbering systems for maintenance actions exist in three forms: as maintenance operation items used by maintenance management systems, as action items used by maintenance crews, and as pay items for contract maintenance. Some DOTs employ multiple numbering systems. Work by DOT crews may be reported in one numbering system for crew activity reports and in another numbering system for a maintenance management system. At most DOTs, there is greater detail in data systems that record crew activities or contract pay items, and greater aggre- gation in management systems for maintenance programs. Both systems are useful. Detail in crew activities and pay items allows simple computation of costs. Aggregation into mainte- nance operations provides an overview of maintenance pro- gram scope and accomplishment. Bridge Maintenance Scope and Definition Definitions of bridge maintenance are collected from AASHTO (1, 12), published materials of state DOTs, and NCHRP reports. Bridge maintenance can be defined by at least the following four means: 1. Policies: Descriptive concepts of the kinds of work and outcomes that are maintenance. 2. Actions: Maintenance denoted by lists of maintenance crew actions and maintenance contract pay items. 3. Budgets: Maintenance identified by the source of funding and by U.S. federal participation, if any, in funding. 4. Data: Maintenance identified and perhaps limited by the capabilities of data systems used in maintenance operations. Maintenance Defined By Policies Policy-level definitions of maintenance are obtained from AASHTO, FHWA, and state transportation agencies. AASHTOâs guide (13) defines maintenance as any activity other than new construction. AASHTOâs maintenance manual C H A P T E R 1 Background on Bridge Maintenance Programs at U.S. Departments of Transportation
(2) more narrowly defines maintenance as routine upkeep and relatively small repairs that keep bridges in good condition. Maintenance actions include routine cleaning and painting as well as repairs and replacements of components. FHWA (33) recognizes these same activities as maintenance. NCHRP Report 131 on budgeting for highway maintenance (30) defines maintenance as actions that preserve assets in their as-constructed condition. This definition excludes improve- ments to existing structures as well as new construction. State DOTs often define maintenance in a similar, narrow sense. Maintenance preserves bridges and can restore bridges to orig- inal condition. New construction and bettermentsâactions that increase capacity or improve function of bridgesâare often excluded. California DOT maintenance manual (22) notes that, main- tenance does not include reconstruction or improvements. Idaho DOT (23) considers improvements part of maintenance. Michigan DOT (6) notes that maintenance projects are of short duration and have little impact on traffic operations. Montana DOT notes that (28) maintenance preserves the originally intended use and function of bridges. Ohio DOT (37) notes that maintenance is intended to keep bridges in original condition. Oregon DOT (20) identifies preserving, repairing, and restoring as maintenance. Texas DOT (21) identifies maintenance in three categories: routine, preven- tive, and major. Texasâ major maintenance includes bridge replacement and bridge reconstruction. Washington State DOT (27) identifies cleaning and minor repairs as normal maintenance. Based on stated policies, cleaning and minor repairs are always maintenance. Repairs or replacements of components are often maintenance. Improvements achieved in small proj- ects might be maintenance. Larger projects for improvement, bridge reconstruction, and bridge replacement are not main- tenance. New construction is not maintenance. Maintenance Defined by Lists of Actions A review of maintenance actions presented by AASHTO and by state DOTs reveals seven common operations in bridge maintenance (Exhibit 1). Most state DOTs identify maintenance actions in all oper- ations shown in Exhibit 1 though terms vary among DOTs. Some DOTs identify minor repair and major repair rather than repair and replace. Some DOTS describe betterments, instead of modify actions. Modify actions, within mainte- nance programs, can include replacement of obsolete rail- ings, extension to drain outlets, and relocation of bracing in truss portal frames. Some DOTs have separate categories for maintenance of movable spans, motion equipment, tunnels, or other structural assets. Maintenance Defined by Budgets Budgets in transportation departments identify funds for the maintenance division, contract maintenance, and equip- ment and materials used in maintenance tasks. The federal Highway Bridge Program (HBP) program has an impact here. Bridge replacement or major rehabilitation projects that are eligible for HBP funds are not maintenance. At the same time, projects that extend life of bridges are mainte- nance and can be HBP-eligible. Eligible maintenance proj- ects usually entail repairs, element replacements, or minor modifications. From the perspective of DOTsâ budgets, cleaning and other routine upkeep are always maintenance. Repairs, component 7 Exhibit 1. Common operations in bridge maintenance. ⢠Clean, Clear actions include sweeping, flushing, removal of incompressibles, removal of vegetation, removal of material in channels, and all similar operations. ⢠Seal, Paint, Coat actions provide spot, partial, or complete application of fluid sealers, paints, coatings or preservatives. ⢠Reset actions include re-positioning, lubrication, and tightening (of bolts and rods). ⢠Repair actions return elements to better condition and perhaps to as-built condition. Patching is a repair action. ⢠Replace actions are replacement, in kind, of all or part of elements. ⢠Modify actions are repairs or replacements that alter elements. ⢠Emergency actions are executed in response to sudden acute problems that must be corrected to restore or continue traffic operations.
replacements, and minor modifications are usually mainte- nance and may be eligible for federal HBP funds. Bridge replacement and major rehabilitations are not maintenance. Maintenance Defined by Data Systems The capabilities of data systems can impose limits on the work that is tracked as maintenance. Maintenance data are the history of maintenance actions executed on bridges. Each bridge is presented to the maintenance database as an entity; as a complete set of descriptive and defining data. A bridge is presented as its National Bridge Inventory (NBI) record, its element-level model, its element-level condition data, etc. Maintenance actions are tied to individual bridges. The exis- tence and immutability of each bridge and its make-up are essential attributes. Projects that replace bridges or greatly alter bridges are not maintenance, in this context, because they are not compatible with the basic organization of maintenance data. Maintenance Categories Maintenance programs consist of two broad categories: cyclic work and singular work. Cyclic work, which includes actions such as deck sweeping, is performed at set intervals. Singular work, such as repair, is performed in response to deficient con- ditions. The categories reveal two distinct origins of mainte- nance projects. Cyclic work is performed in response to DOT policy. Singular work is performed in response to inputs from bridge inspections and road surveys. A third category, updat- ing, may be added. Updating is work to replace obsolete ele- ments such as bridge railings, when the replacement is per- formed as part of the maintenance program. DOTs use various names for these categories of maintenance. Terminology is addressed in Chapter 6. Contract Maintenance Contracts for bridge maintenance work include site contracts that deliver a fixed schedule of repairs at a fixed set of bridges, open-ended contracts that provide specified maintenance actions, and asset management contracts that provide a level of service along a route (Table 1). Site contracts are construction contracts that deliver a set of repairs or treatments at bridges. Open-ended contracts offer a schedule of maintenance actions that district managers can direct to bridges. Asset management (AM) contracts place responsibility for both the identification of maintenance needs and the execution of work with the con- tractor. In AM contracts, DOTs make periodic inspections of assets to verify that the level of service is adequate. In bid processes, site contracts entail bidding on a fixed schedule of items with fixed quantities. Open-ended contracts entail bidding on a fixed schedule of actions with estimated quantities; quantities are estimated for the first yearsâ work in the contract based on known maintenance needs. Asset Man- agement contracts entail bidding on a schedule of actions and 8 DOT Contract Note Delaware Open-end 3-year duration, Standard maintenance actions and costs, Maximum contract amount. Florida AM Maintenance action executed when requested by DOT. Site Bridge rehabilitation, Bridge replacement. Michigan Site Capital scheduled maintenance, Capital preventive maintenance. New York Site Larger maintenance projects. Job Order An open-ended contract type using a construction task catalog of fixed prices. Suited to replacement-in-kind maintenance needs. Hybrid Contracts that provide bid items, quantities and engineering design plans for one among a set of similar projects. Schedule of bid prices are applied to additional, similar projects as quantities and engineering design become available. Oregon Site Small contracts are administered within districts. Larger projects go toOrDOTâs central procurement. Virginia Open-end District-wide contracts having 3-year duration and renewed each year. Contracts funded at $2MM annually. Contracts have 95 bid items for both ordinary and preventive maintenance, and a mix of federal-eligible and non-eligible actions. AM Turnkey asset management (TAM) contracts are used for operations and minor repairs along interstate routes. Design Consultant design services are available to VaDOT districts through three, open-ended, regional contracts. Washington Job Order An open-ended contract type. Used for maintenance actions at ferry terminals. Table 1. Bridge maintenance contracting (14).
estimated quantities intended to deliver a specified level of service along a route. Summary on Bridge Maintenance Scope Bridge maintenance can be defined in terms of policy statements, lists of actions, budget status, and the capabil- ities of maintenance data systems. U.S. DOTs recognize maintenance as distinct from new construction, replacement of structures, and major rehabilitation of structures. Clean- ing, painting, and minor repairs are always maintenance. Replacement or modification of portions of bridges may be maintenance if projects are small and have a short duration. Large projects are construction, rather than maintenance. Emergency work, usually in response to accidents or extreme events, is classified as maintenance and can entail significant, temporary modifications of bridges. Terms in Bridge Maintenance This section reports a set of frequently used terms in bridge maintenance. Chapter 6 provides a glossary of terms collected from DOT maintenance manuals and guides. Bridges are structures included in the National Bridge Inven- tory System (NBIS) (35). Bridges may include short spans and minor culverts. Bridge components include the five com- ponents that appear in the NBIS (deck, superstructure, sub- structure, channel, culvert) plus six components that are identified in maintenance work (joints, drains, railings, bear- ings, approaches, movable bridge). Bridge elements include AASHTOâs commonly recognized bridge elements (1) plus additional elements defined by DOTs. Bridge devices are pre- fabricated parts such as railings or bearings that can be replaced as individual units (Exhibit 2). An Operation is a kind of maintenance (Exhibit 3). An Activity is a general method for an operation. A maintenance Event is the accomplishment of one operation, on one bridge, at one time. A maintenance Record is the collection of data for one maintenance event. A maintenance Item is the identifica- tion, usually by a numerical code, of a maintenance action. Costs of maintenance are computed from usages of resources. Resources include Labor, Equipment, and Materials for DOT crew work, and pay items and quantities for contract maintenance (Exhibit 4). Labor costs are sums of employee hours and labor rates. Equipment costs are sums of equip- ment usage and equipment rates. Material costs are sums of material quantities and unit costs. Contract costs are sums of pay Item quantities and bid prices. Maintenance Accomplish- ments are quantities of maintenance work completed. These may be expressed in units specific to maintenance operations, or as quantities of bridge elements that receive maintenance. 9 Exhibit 2. Terms describing bridges. Bridge: A structure carrying traffic over a span of greater than 20 feet, as defined in NBIS (Ref 42). Culverts, as defined in NBIS. Component: One among the major regions or assemblies of a bridge. There are five NBIS components (deck, superstructure, substructure, channel, culvert), and six additional components that are objects of maintenance (joints, drains, railings, bearings, approaches, movable bridge). Element: One among AASHTOâs commonly recognized elements, or among additional elements defined by DOTs. Device: A part that can be replaced as a unit, often without demolition of attached portions of the bridge. Exhibit 3. Terms describing maintenance work. Operation: A type of maintenance work, being one among: Clean, Reset, Coat, Repair, Replace, Modify, Emergency. Activity: A method of performance of an operation. Event: The accomplishment of an operation at a specific structure, on specific dates, in specific quantities, incurring specific costs and delivering specific improvement. Record: Data for one event, identifying the structure, the action, the date, the resources used, the action quantity accomplished, and the improvement to bridge condition. Item: The identifying number of a maintenance action.
Maintenance Outcomes are the improvements to bridge con- ditions achieved by maintenance events. Most DOTs recognize categories of maintenance. These are variously called Scheduled/Response, Preventive/Routine, or Proactive/Reactive. These terms have different and sometimes conflicting meanings for different DOTs. Exhibit 5 lists these terms as they are defined by AASHTO and by DOT sources. Condition ratings are integer values indicating the presence and severity of defects at bridges (Exhibit 6). In practice in the United States, ratings usually denote the 9-to-0 scale used in the NBIS and applied to bridge components. Condition States are also integer values indicating the presence and severity of defects. States usually denote the 5-valued and 4-valued scales used for AASHTOâs commonly recognized bridge elements. Road Surveys report presence of debris, graffiti, and other defi- ciencies in upkeep along routes and at bridges. Similar data may be called maintenance assurance values, maintenance quality data, or simply field data. Condition ratings and con- dition states are usually reported by bridge inspectors. Road survey data are reported by road maintenance crews. Summary on Maintenance Terms Selected terms describing bridge features, maintenance work, costs, and condition data are defined in this section. Most of these terms are familiar, and the definitions given here are com- 10 Exhibit 4. Terms related to maintenance cost. Resource: Any measurable contributor to the cost of maintenance. Resources include labor, equipment, materials, and pay items. Labor: As a resource, the set of employees and hours. As a cost, the sum of products of hours and rates. Equipment: As a resource, the set of equipment types and usages. As a cost, the sum of products of equipment usages and rates. Materials: As a resource, the set of material items and quantities. As a cost, the sum of products of material quantities and unit costs.. Pay Items: As a resource, the set of pay items and quantities. As a cost, the sum of products of pay items and bid prices. Accomplishment: The quantity of maintenance work that is completed, expressed in action units, or bridge element units or both. Outcome: Improvement to condition ratings or road survey data achieved by a maintenance event. Exhibit 5. Terms describing maintenance categories. AASHTO (2) Scheduled: Work programmed at intervals. Response: Done as needed and as identified through the inspection process. Alabama (11) Routine Limited Activities: Quantities of work that can be established and firmly adhered to. Control is exercised on the basis of planned work units. Examples: Mowing, Bridge Inspection. Routine Unlimited Activities: High priority work performed when needed in the amounts required to minimize deficiencies. Oregon (20) Proactive: Activities planned in advance to reduce lifecycle costs; inspection, upkeep. Proactive: Activities planned in advance to forestall significant damage. Preservation or restoration activities. Reactive: Incident driven activities. Performed to correct or respond to immediate problems. Texas (21) Preventive Maintenance: Steel structure cleaning and repainting; installation of other coatings; installation of bridge deck protection; joint cleaning and sealing or replacement. Routine Maintenance: Repair of substructures, superstructures, decks, joints, approach slabs, and railing; spot painting; repair and operation of movable bridges; installation of temporary bridges; repair and installation of fender systems.
monly used. Three termsâOperation, Activity and Eventâ have a special role in the database developed in this project. A larger list of terms collected from DOT maintenance manuals is provided in Chapter 6. Maintenance Actions U.S. state DOTs perform similar maintenance work, but there are differences in the level of detail used to record main- tenance accomplishments and to distinguish methods and products. Sets of maintenance actions are collected from public doc- uments including the following: ⢠Manuals on maintenance policies and recommendations. These provide descriptive information on maintenance actions but might not contain formal numbering and measurement units for actions. ⢠Manuals for maintenance foremen and maintenance crews. These usually report formal procedures for recording and reporting maintenance activities. Reporting includes crew size, crew activities, materials used, and equipment used. Often, measures of indirect activities such as traffic control, travel time, and preparation at the maintenance yard, are included. ⢠Manuals for information systems. These list the numbers (IDs) for maintenance actions. At some DOTs, different maintenance information systems are used by different department branches. The branch tracking costs might employ a management system that reports maintenance operations, with each operation covering many related actions. The maintenance crews may use a more detailed list of actions. Details of information from AASHTO and from state DOTs are reported in the following section. A summary of cate- gories of bridge maintenance work and maintenance actions reported by AASHTO and state DOTs are provided in several tables in Appendix A. AASHTO Maintenance Manual The AASHTO maintenance manual (2) identifies various bridge elements, discusses their common modes of deteriora- tion, and presents actions for maintenance of these elements. The maintenance manual does not provide a formal list of maintenance actions, but maintenance actions are evident in the narrative. AASHTO actions are presented for bridge deck, superstruc- ture, substructure, joints, drains, curbs, railings, approach pave- ment, approach embankment, and channel. The following are the six maintenance operations: ⢠Clean, Clear; ⢠Seal, Paint, Coat; ⢠Reset; ⢠Patch; ⢠Repair; and ⢠Modify. The AASHTO presentation includes several actions for each operation, taking into account different types of bridge ele- ments, different methods of maintenance, and different repair products. The AASHTO actions include major operations. For decks, actions such as installation of cathodic protection, place- ment of concrete deck overlay, deck replacement, and asphaltic overlay with waterproofing membrane are included. For chan- nels, AASHTO actions include construction of revetments, placement of channel liners, and construction of check dams. Alabama DOT The Alabama DOT (11) identifies basic maintenance oper- ations as the following: ⢠Cleaning, ⢠Painting, ⢠Minor Repairs, ⢠Major Repairs, ⢠Moveable Span Maintenance, ⢠Tunnel Maintenance, and ⢠Other Structure Maintenance. Alabama DOT uses two systems of numbering for main- tenance actions. The Alabama maintenance management system uses six numbers (645â650) to identify operations. Alabama maintenance crews report their accomplishments as âBâ codesâa set of 39 actions (11). The Alabama B codes rec- ognize eleven components: Bridge, Movable Spans, Deck, 11 Exhibit 6. Terms describing field data. Condition Rating: An integer value indicating presence and severity of defects in a bridge component. Condition State: An integer value indicating presence and severity of defects in a bridge element. Road Survey, Assurance Value, Quality Data, Field Data: Reports of presence and extent of debris graffiti or other upkeep deficiencies.
Joints, Curbs/Rails, Superstructure, Substructure, Slopes/ Shores, Culverts, Navigation Lights, and Tunnels. For most components, the actions include cleaning, coating, minor repair and major repair. California DOT Bridge maintenance actions are reported in Chapter H of the California Maintenance Manual (22). California mainte- nance actions include cleaning, coating, repair, rehabilitation, and replacement of bridge components. Colorado DOT Colorado DOT employs two sets of maintenance actions. One set is coordinated with Coloradoâs implementation of the Pontis Bridge Management System (32). This set has 40 actions with identifying numbers between 351 and 399. The set recog- nizes eight bridge components (Bridge, Deck, Expansion Joints, Curbs/Rails, Superstructure, Bearings, Substructures, and Approaches). The actions include cleaning, painting, reposi- tioning, lubricating, tightening and repairing. Activity 398 is used to identify miscellaneous work such as repair of utilities. Activity 399 is reserved for identifying deficiencies that require engineering design to accomplish a repair. Separately, contract maintenance is organized as pay items. Annually, Colorado DOT tabulates average costs for pay items in maintenance contracts (39), as well as annual item data books (17). Contract actions include the full range of cleaning, paint- ing, repairing and replacement actions. Florida DOT The Florida DOT maintenance management system (MMS) includes 14 actions. The actions identify the components. The components are Bridge, Deck, Drains, Railings, Superstructure, Substructure, Channel, Electrical Systems, and Mechanical Systems. Actions for each component include both mainte- nance and repair. Georgia DOT Georgia DOT lists 13 actions in its Bridge Information Management System (BIMS) (5). The components are Bridge, Decks, Curb/Rails, Joints, Superstructure, Substructure, Approach Slab, and Culverts. Most actions provide for major repair or replacement of components. One action, number 845, provides cleaning, routine maintenance and minor repair for most components. Idaho DOT The Idaho maintenance manual (23) describes, in text, a set of 52 actions. The actions address 10 components: Bridge, Decks, Joints, Bearings, Curb/Railing, Substructure, Approach Pavements, Channel, Culvert, Accessories, and Signs/Utilities. Under Accessories are actions for drainage systems, catwalks, sidewalks, cathodic protection systems, de-icing systems, fill stabilization, walls, and slope paving. Maintenance actions provide cleaning, clearing, painting, repairs, replacements, and modifications. Illinois DOT Illinois DOT lists 139 maintenance actions in the manual for the Illinois Highway Information System, ISIS (16). The com- ponents are: Bridge, Decks, Drains, Joints, Railings, Superstruc- ture, Bearings, Substructure, Slopes, Approach Pavements, Channels, and Miscellaneous. Under Miscellaneous are actions for lighting, and movable bridges. Maintenance actions include cleaning, clearing, painting, sealing, patching, repairs, replace- ments, modifications and removal of structures. Illinois actions are further defined by repair products. Paint- ing is an example. ISIS has 26 codes identifying paint material and manner of application. Illinois records as many as four paint codes per bridge to identify the various paints used. Maryland DOT Maryland DOT (4) uses open-ended maintenance contracts within DOT regions to perform actions such as deck patching, clearing drains, debris removal, slope protection, and under- deck timber planking. Separate contracts for bridge painting include items for zone painting, overcoating, and complete removal and repainting. Michigan DOT Maintenance actions are collected from the Michigan DOT Bridge Capital Scheduled Maintenance Manual (CSM) (6). The CSM manual lists maintenance first as operations and then as specific actions within each operation. The operations are the following: ⢠Superstructure Washing; ⢠Vegetation Control; ⢠Drainage System Cleaning/Repair; ⢠Spot Painting; ⢠Joint Repair/Replacement; ⢠Concrete Coating/Sealing; ⢠Minor Concrete Patching and Repair; ⢠Concrete Crack Sealing; ⢠Approach Pavement Relief Joints; and ⢠Slope Paving Repair. Within each operation, specific actions differ in repair method or material. The CSM manual addresses contract maintenance work and lists 51 maintenance pay items. Addi- tional information, collected from Juntunen (18), indicates that zone painting, full painting and epoxy overlays for decks are also maintenance actions. 12
Montana DOT The Montana DOT Maintenance Manual (25) identifies both state-force maintenance and contract maintenance. Maintenance and repair of structures are provided by a set of 13 actions that include cleaning, clearing (drains), debris removal, adjustment/tightening of parts, and repair of ele- ments. Contract maintenance is used for maintenance overlays, crack sealing, and coatings. Montana DOT performs mainte- nance actions in response to visible deficiencies. Montana DOT employs a readable system for numbering of mainte- nance actions (as opposed to a simple index). Each action is identified by a four digit sequence composed of the following: ⢠A single digit for highway asset, ⢠A single digit for purpose of the action, and ⢠Two digits identifying a specific action. Bridges are highway asset â4,â and preventive maintenance is purpose â1.â Actions for preventive maintenance of bridges are numbered â41XX,â where âXXâ are from a list of the spe- cific activities. New Hampshire lists bridge maintenance actions for deck, beams, trusses, joints, and rails. New York State DOT New York State DOT (38) identifies cyclic maintenance actions including deck washing, concrete sealing, bearing lubri- cation, bridge painting and deck overlays. Repairs, replace- ments, and modifications to reduce vulnerability are also maintenance, though not cyclic. New York associates some maintenance actions with specific construction materials or element types. In addition, maintenance actions are appro- priate only for structures within a stated range of condition ratings. North Carolina DOT North Carolina DOTâs program for preventive maintenance (10) includes bridge painting, joint repairs, and rehabilitation of decks. Ohio DOT Ohio DOTâs bridge maintenance actions are collected from the on-line Bridge Maintenance Manual (29), the Transporta- tion Management System (TMS) Foremanâs Manual (37) and the Maintenance Administration Manual (19). The on-line maintenance manual is an illustrated guide to maintenance and repair of bridges. The on-line manual recog- nizes eleven bridge components (Bridge, Deck, Drains, Joints, Railings, Sidewalks, Superstructure, Substructure, Approach, Channel, Culvert) and six operations (Clean, Coat, Reset, Repair, Replace, Modify). The on-line manual recognizes dif- ferent bridge elements (by type of joint, type of bearing, etc.), different construction materials, and different repair products. Starting with eleven components and six maintenance opera- tions, the multiplicity of elements, materials, and products yield a list of 300+ actions in bridge maintenance. A formal list of 126 maintenance actions appears in Ohioâs TMS Foremanâs Manual (37). These actions are used in report- ing crew work and accomplishments. These actions address the maintenance programs for bridges, roadways, and facilities. There are 43 actions related to bridges and culverts. These actions recognize the same components and basic actions found in the on-line maintenance manual. Oklahoma DOT Oklahoma DOTâs (31) actions for bridge maintenance include painting, sealing, and repairs to decks, superstructure, and substructure. Repair methods include use of synthetic fiber wraps for reconstruction of concrete elements, and the rebuild- ing of steel beams by cutting out deteriorated portions (ends of beams, often) and welding in a matched section of steel. Oregon DOT Oregon DOT employs two numbering systems for main- tenance actions (20). A set of nine actions is used in the MMS. These MMS actions recognize three structures (Culvert, Bridge, Movable Bridge) and four operations (Clean, Coat, Maintain, Repair). A separate numbering system, called TEAMS, is used by DOT work crews to report production. There are 49 TEAMS actions for bridges. The TEAMS actions recognize nine com- ponents (Movable Bridge, Deck, Drains, Walks/Rails/Curbs, Superstructure, Substructure, Slope, Channel, Culvert); four construction materials (Concrete, Steel, Timber, Any); and a few bridge elements. Pennsylvania DOT Pennsylvania DOT lists bridge maintenance actions in its Procedures and Standards for Bridge Maintenance (34). The pub- lication lists procedures that include operations for cleaning, resetting, repairing, replacing, and modifying. Often, separate procedures are listed for similar actions applied to different structure types or different construction materials. Maintenance procedures recognize 12 components (Bridge, Deck, Drains, Joints, Railings, Sidewalks/Curbs/Parapets, Superstructure, Bearings, Substructure, Approach, Chan- nel, Culvert). Actions provide cleaning, repositioning, tightening, coating, repairing, replacing, and modifying of components. Actions are identified under two numbering systems: the Maintenance of Roadways Information System (MORIS) cost functions and the BMS activity numbers. MORIS lists 31 actions for bridge maintenance. The MORIS numbers 13
aggregate similar actions for different structure types or construction materials. There are 77 BMS activity numbers for bridge maintenance. The BMS activities recognize distinc- tions among elements, though a single BMS activity can corre- spond to more than one procedure. An overview of Pennsylvaniaâs bridge preservation program is provided by Rogers (36). Texas DOT Texas DOTâs (3, 21, 26) maintenance actions recognize nine components (Bridge, Deck, Drains, Joints, Railings, Super- structure, Substructure, Approaches, Channel). The actions provide for cleaning, coating, repair, and replacement of com- ponents. Contract maintenance projects are organized as stan- dard pay items. Texas DOT (8) developed standard repair details for the guidance of maintenance personnel. The general goals of preventive maintenance are to keep joints clean and sealed, control drainage, clear debris from channels and maintain bearings. Virginia The Virginia Transportation Research Council (VTRC) identifies washing, sweeping, lubrication, joint sealing, over- lays, vegetation control, and zone painting among preventive maintenance actions (7). Repairs, element replacements and modifications are also maintenance. Modifications include retrofit of fatigue-prone details and installation of cathodic protection systems. VTRC reports intervals and average costs for some actions in preventive maintenance. Washington State DOT Washington State DOTâs maintenance program recognizes two classes of structures (24). Major structures are bridges on the state bridge list. Minor structures are drainage structures, retaining walls, noise barriers, etc. Area maintenance crews take actions to sweep decks, remove debris on components, and clear drains. Other repair works on bridges are the respon- sibility of the state Bridge Preservation Engineer. Washington DOT provides detailed guidance for compli- ance with environmental regulations, especially for activities that can affect waters of the state. Programmatic permit guides are provided for the following: ⢠Bridge Maintenance Washing and Cleaning, ⢠Bridge and Ferry Terminal Deck Overlay Replacement, ⢠Bridge and Ferry Terminal Deck and Drain Cleaning, ⢠Bridge General Maintenance and Repair, and ⢠Bridge Paint-Prep Washing and Blasting. Summary and Maintenance Actionsâ Existing Practice Maintenance operations at most DOTs include cleaning, coating, and repairs. Many DOTs also include operations for replacement (usually of parts or portions of bridge compo- nents), for minor modifications, as well as actions for lubrica- tion and other actions to reset devices on bridges. Maintenance actions at most DOTs are distinguished by construction mate- rial (repair steel versus repair concrete) or by type of work (patch beam versus straighten beam). Most DOTs recognize bridge components as objects of maintenance actions, and most recognize more than the five NBIS components. Some DOTs recognize separate mainte- nance actions for different types or forms of bridge component. These are element-level distinctions, though CoRe elements are not often used directly. Numbering systems for maintenance actions exist in three forms: as maintenance operation items used by maintenance management systems, as action items for maintenance crews, and as pay items for contract maintenance. Some DOTs employ more than one numbering system. At most DOTs there is greater detail in recording crew activities and contract pay items, and greater aggregation in maintenance operations tracked by management systems. Both are needed. Detail in crew activities and pay items allows simple computation of costs. Aggregation into maintenance operations provides an overview of maintenance program scope and costs. Bridge Maintenance Dataâ Existing Practice Data in bridge maintenance programs identify and quantify: actions taken, usages of resources, and quantities of accom- plishment. Direct uses of data include cost computations and computation of resources needed for unit accomplishment of maintenance actions. Reports are summaries of maintenance data for a type of action, a DOT region, a time period, or other organizing basis. Evaluations are comparisons of cost and ben- efits in various guises: cost for maintenance quantity, cost for maintenance quality, comparative costs of repair products, comparative productivity of different equipment or crew size, etc. Programmatic evaluations are needed for Governmental Accounting Standards Board (GASB) reporting and life-cycle cost computations. Maintenance management, finally, is the intelligent application of reports and evaluations to estimation of future needs and planning. Users of maintenance data include maintenance crews, foremen, and regional superintendents, all working with information on resource needs and production rates for maintenance actions. DOT maintenance directors use reports 14
of maintenance data to justify budget requests and report achievements of maintenance programs. Bridge engineers use maintenance data in the evaluation of products and methods. Maintenance Data Data are considered in two sets: data on usage of resources and data on conditions of bridges. Each has two subsets. For resources, there are data on resources used in work by DOT crews, and there are data on pay items and quantities for con- tract maintenance. For conditions, there are data from bridge inspections and data from surveys by road crews. Data on Resources Data on resources include all labor, equipment, and mate- rial needed to accomplish a maintenance task (30). This con- cept is evident in some state DOT policy statements (Table 2) and in the forms used for reporting crew maintenance work and contract maintenance. Maintenance by DOT Crews A primary source of data for work by DOT crews is the crew card (also called day card, daily work report, daily time card, etc.). Crew cards provide information on resources and accomplishments. Examples are found in the Ohio DOTâs Transportation Management Systemâs Foremanâs Manual (37) and the Alabama DOTâs Field Operationâs Manual (11) (Fig- ure 1). Typical content of crew cards includes the following: ⢠Work Administration â Maintenance unit number and name â Job number or index to maintenance program plan â Date(s) â Crew Leader name or ID ⢠Work performed â Action Number and name â Activity Numbers and names ⢠Exact location where the work was performed â Bridge ID â Optional: Location on a bridge identified by span, lane, beam line, etc. 15 DOT Policy Ohio (37 ) It is intended that all work effort, inclusive of layout, mobilization, final clean up, etc., that contributes directly to achieve the accomplishment of the item be charged to the itemâs Program Activity Code. (All work is part of the activity, and not a separate item or cost. This will lead to different apparent costs when traffic control is provided for a single activity and when traffic control allows several activities to occur together.) Ohio (19) It is imperative that ODOT capture the cost of using in-house resources to perform the work necessary to reach its goals. This information will be used in various ways including the following: ⢠As a tool to assist managers in allocating resources based on projected workloads. ⢠To compare costs of performing similar activities between districts, determine desired performance thresholds, and identify best practices of those business areas that perform within the cost thresholds. ⢠To accurately compare in-house costs to costs of outsourcing. ⢠To calculate overhead rates for the Department, District, County and Garage. ⢠To refine allocation methods relating to overhead rates as the process becomes more defined. ⢠To monitor accountability and accuracy of the data in TMS through Quality Assurance Reviews. Texas (21) Provide data on work load and cost of maintenance activities to support budgeting and planning efforts; Provide a tool for analyzing maintenance activities so that production efficiency can be improved; Help identify sections of highway which qualify for rehabilitation; Document the work accomplished in order to support the departmentâs budget requests to the legislature; and Provide data to compare costs of maintenance activities performed under contract with those performed by state forces. Table 2. Policies on maintenance costs.
⢠Labor Usage â Crew Size â Employee names or IDs â Number of hours worked by each employee on each activity ⢠Equipment Usage â Equipment Type(s) and ID(s) â Miles or hours used for each type of equipment â Miles or hours used for each activity ⢠Material Usage â Material Item Number(s) â Quantities of materials ⢠Work Accomplishment â Work unit â Number of units accomplished Crew cards identify the maintenance yard, date of work, and crew leader. The crew card may include a job or authorization 16 Figure 1. Work reporting formâFlorida DOT.
number that places this work within the maintenance pro- gram plan. The work itself is identified by an action num- ber or description. The location of work is shown, at least as bridge ID, and possibly as a span, lane, beam line, etc., on the bridge. Labor usage is recorded as employees and hours. Equip- ment IDs and usage are shown. Material item numbers and material quantities are shown. Work accomplishment is shown. Labor usage for indirect activities on crew cards can include yard preparation, travel time, mobilization, traffic control, work interruptions, and clean-up. Some DOTs use standard codes to identify such activities. There are other indirect activ- ities such as administration, inspections, equipment transfer (between yards), and material stockpiling, that are not recorded on crew cards. Crew cards often record work order numbers. The bridge ID, job authorization number, and maintenance action are entered in advance by maintenance administrators. A crew leader receives the card, executes the action, records usages of labor, equipment and materials, and returns the completed card to maintenance administration. Usually the information on a crew card can be tied to a spe- cific bridge. However, there are exceptions when a crew per- forms multiple activities on a single bridge or the same activ- ity on multiple bridges. There is a related issue: all the work performed on a particular bridge might not be recorded on one daily work report if either multiple days or multiple crews are used. Some DOTs have implemented MMS that are driven by work orders. In principle, a work order is issued for each defi- ciency on a bridge, and when the work is completed, the work order is closed out. The Florida work reporting form (Figure 1) includes both field data and office data. Identification of crew members, equipment, materials, and quantities are field data. Crew pay rates, equipment rates, and material unit costs are office data. The extended costs are office computations (Table 3). Contract Maintenance Resources used in contract maintenance are reported as pay items and quantities. A single pay item may combine labor, equipment, and material costs. Reports (billings) from con- tracts may provide the following: ⢠Pay items and quantities for a single maintenance action at one bridge, ⢠Pay items and quantities for the same action at more than one bridge, ⢠Pay items and quantities for multiple maintenance actions at one bridge, and ⢠Pay items and quantities for a project that includes both maintenance and non-maintenance actions. To record resources expended for each maintenance action at each bridge, it may be necessary to allocate pay items among several actions and several bridges. Further allocation may be needed to identify resources for direct and indirect activities. Condition Data Maintenance can improve conditions of bridges. Measures of improvement can be used in evaluations of effectiveness of maintenance actions. For bridges, condition data are avail- able as CoRe element condition reports, as National Bridge Inventory (NBI) condition ratings and as road survey values. CoRe element condition reports list element quantities in condition states (1). For many elements, more than one con- dition state may be reported. Condition states indicate defects. The response, naturally, is repair or replacement. CoRe condi- tion states are defined separately for separate elements. CoRe language is specific, and is intended to foster simple, consistent assignment of conditions states for observed conditions. A condition state may name more than one defect or visible indicator of condition. The CoRe report of condition states does not identify which defect is present. As a result, a condi- tion state can correspond to several maintenance actions that might be needed, but the condition state does not indicate a specific maintenance action (Table 4). NBI condition ratings are more general (35). Three ratings, one each for deck, superstructure and substructure share a common set of definitions. The naming of multiple defects is absent. Both extremes of the NBI rating scale are infrequently used. Rating 0 for failed bridges is not frequently needed. Rat- ing 9 for new or near-new bridges is rarely used. NBI condi- tion ratings indicate the need for a maintenance operation, but not a specific maintenance action (Table 5). Channels and culverts have separate definitions of NBI condition ratings (see Tables 6 and 7). 17 Field Data Office Data Office Computation Employee names, job titles, and hours Employee hourly rates Labor cost Equipment types, IDs, and usage Equipment rates Equipment cost Material types, items and quantities Material unit costs Material cost Table 3. Field data and office data.
Condition information is also available from road surveys. These data are variously called quality survey data, level-of- service data, assurance data, or simply field data. Road surveys report debris, sand/grit, problem vegetation, graffiti, and other conditions that can contribute to deterioration. Maintenance can be cleaning, clearing, spot painting, and resetting. Reports Some DOTs develop Performance Standards (30) for main- tenance actions. Each maintenance action has its own per- formance standard, and each performance standard indicates the resources needed to complete a unit accomplishment of the action. Performance standards are useful in planning and scheduling maintenance work, and typically include the following: ⢠Crew size/Labor requirements; ⢠Kinds and number of equipment used; ⢠Suggested procedures; ⢠Material quantities; ⢠Average daily accomplishment; and ⢠Authorizations, permitting and scheduling constraints. Maintenance data provide the average values for required labor, equipment and materials, and the average values of accomplishment using these resources. An example perfor- mance standard is taken from Pennsylvania DOT is provided in Figure 2. 18 Code Description Operation N Not applicable 9 Excellent condition Clean 8 Very good condition Clean 7 Good condition Reset 6 Satisfactory condition Reset, Coat 5 Fair condition Repair, Coat 4 Poor condition Replace, Modify 3 Serious condition Modify, Emergency 2 Critical condition Emergency 1 âImminentâ failure condition 0 Failed condition Table 5. NBI and maintenance operations: deck, superstructure, and substructure. Code Description Operation N Not applicable. 9 No noticeable or noteworthy deficiencies. 8 Banks are protected or well vegetated. 7 Bank protection is in need of minor repairs. Clear, Reset 6 Bank is beginning to slump. Clear, Reset 5 Bank protection is being eroded. Clear, Repair 4 Bank and embankment protection is severely undermined. Replace 3 Bank protection has failed. Replace, Modify 2 The bridge is near a state of collapse. Modify, Emergency 1 Bridge closed because of channel failure. 0 Bridge closed because of channel failure. Table 6. NBI and maintenance operations: channel. Bridge Element Condition State Concrete Deck Steel Beam Concrete Substructure 1 Clean, Seal surface Clean Clean 2 Patch, Seal cracks, Seal surface Spot paint Patch, Seal cracks, Seal surface 3 Patch Spot paint, Full paint Patch 4 Patch, Replace Portion, Modify protection Full paint, Repair, Patch, Replace Portion, Modify protection 5 Patch, Modify protection, Replace Entire Repair, Replace Patch, Modify protection, Replace Entire Table 4. Maintenance actions for CoRe condition states.
Summary of Maintenance Data and Uses Maintenance data include information on resources which are used to compute costs and information on bridge condi- tions which are used to quantify improvements. Using these data, various evaluations can be made to present the cost and effectiveness of maintenance actions or the scope and accom- plishments of maintenance programs. Performance standards are derived from maintenance data. Maintenance Management Systems MMSs use maintenance data, reports, and evaluations to support decisions in maintenance programs. Management functions build upon basic reports and evaluations. Aspects of maintenance management are reviewed here. Maintenance Management Modules AASHTO guidelines (13) identify six modules for MMS: Planning, Programming, Resources, Scheduling, Monitoring, and Administration. For MMS, each module combines diverse inputs on conditions of structures, maintenance actions, finan- cial resources, physical resources, public input/perceptions, DOT policies, and DOT goals. Planning. MMS planning proceeds from maintenance needs and feasible actions. MMS may automate the identifi- cation of some maintenance needs based on the comparisons of current conditions of structures with target values for con- ditions. Other needs may be based on a desired interval (for cleaning, etc.) without specific reliance on condition data. Programming. MMS composes work programs based on maintenance needs, priorities among needs, and constraints imposed by available resources. Priorities may be based on condition data available from a BMS database. BMS optimiza- tion routines can be primary sources in formation of mainte- nance programs. Resource Management. MMS evaluates needs in fund- ing, labor, equipment, and materials as the aggregate of needs 19 Code Description Operation N Not applicable. Use if structure is not a culvert. 9 No deficiencies. 8 No noticeable or noteworthy deficiencies. 7 Insignificant damage not requiring corrective action. 6 Deterioration or initial disintegration. Repair 5 Moderate to major deterioration or disintegration. Repair 4 Considerable settlement or misalignment. Repair, Replace 3 Severe movement or differential settlement of the segments. Replace 2 Corrective action required to maintain traffic. Emergency 1 Bridge closed. Corrective action may put back in light service. 0 Bridge closed. Replacement necessary. Table 7. NBI and maintenance operations: culvert. MORIS 711-7431-01, BMS Activity: A743101, Clean/Flush Deck Unit of measurement: Each Bridge ACTIVITY REQUIREMENTS LABOR EQUIPMENT MATERIAL Number Classification Number Type Amount Description 1 Foreman 1 Sweeper Water 2 Crew members 1 Water tank, compressor, hoses 1 Equipment operator 1 Front end loader PRODUCTION UNITS / HR PLANNING UNITS PERFORMANCE STANDARD Bridges / HR 3 Bridges / Day 8 MH / Bridge Figure 2. Performance standard: Pennsylvania DOT (34).
for all actions in the current maintenance program. Needs in each category are also broken down by DOT region, so that appropriate distribution of resources can be achieved. Scheduling. MMS schedules individual maintenance actions based on needs, on available crews and equipment, and (often) with consideration of impacts on network traffic operations. Monitoring and Evaluation. MMS tracks work accom- plishment, resources used, productivity, costs, and improve- ments to conditions. Maintenance Support and Administration. MMS assists in coordination of maintenance events with regulatory agen- cies, public-interest programs, safety programs and resource management. MMS embodies, as a set of logical rules, knowl- edge of the restrictions imposed by statute or regulation, and of stakeholders in activities that are in line with or in support of the maintenance program. Maintenance data contribute to the operation of all six modules. Some of these contributions are indicated in Table 8. Commercial Maintenance Management Systems For reasons of financial accountability, DOTs employ some means for recording the dates, locations, maintenance activ- ities, resource utilization, and accomplishment for work per- formed by DOT crews. These data are normally entered into highway maintenance management systems (HMMS). There are several commercial HMMS available to DOTs. There is not much uniformity among commercial systems. The number of activities defined in these systems range from roughly 30 to 80 activities. DOTs with HMMS distinguish between activities for planning purposes and for recording work accomplishments. HMMS originally provided for record- ing short lists of maintenance activities, but evolved to record activities plus work methods, in effect multiplying the num- ber of distinct maintenance actions that HMMS could track. There are a number of vendors of commercial off-the-shelf software for management of plant maintenance. These systems are intended for maintenance of equipment, vehicles, and facil- ities, but can be applied to bridges. One drawback to use in bridge maintenance is the lack of location referencing capabil- ities. Plant maintenance systems are adapted to ID numbers. Bridge maintenance requires both bridge ID and bridge linear referencing data. However, toll authorities have found the soft- ware practical because of the need to maintain their toll facili- ties, and their bridge networks are much smaller and funda- mentally different than state highway networks. Collectively, the major vendors have an installed base of tens of thousands of plant maintenance management systems in various com- mercial, government and quasi-government entities including toll authorities. Summary on Bridge Maintenance Programs in the United States U.S. DOTs have programs for maintenance of bridges that are similar in the physical activities performed, but different in the identification and reporting of actions. Each DOT rec- 20 MMS Module Maintenance Actions Condition Data Resource Data Planning Catalog of feasible actions for element and condition Condition of element shows need for maintenance Programming Selection of a feasible action Condition report may indicate quantity of element needing maintenance Resources requirements estimated from performance standard Resource management Performance standard indicates materials needs Scheduling Standard action may include a recommendation for scheduling Performance standard indicates crew type, and equipment type Monitoring and Evaluation New condition data, after maintenance, indicates level of improvement Actual usages of resources are reported Support & Administration Standard action may require permits Network conditions Reports of usage of resources contribute to budgeting process. Table 8. MMS and contributing maintenance data.
ognizes a boundary between actions that are maintenance and actions that are (re)construction, but different DOTs do not recognize quite the same boundary. Each DOT identifies the resource amounts and resource costs used in bridge mainte- nance, but various DOTs employ differing identifications and measurement bases for resources. Condition data for bridge components (NBI ratings) and bridge elements (CoRe condi- tion states) are similar among U.S. DOTs. Some DOTs define additional bridge elements. Current practices in bridge maintenance programs have implications for a national database system for bridge mainte- nance data. A national system must resolve the different num- bering systems for maintenance actions used by DOTs. A national system must accommodate all kinds of work that DOTs identify as bridge maintenance. A national system must accept the different approaches to identification and measurement of resources used by DOTs. A national system must accommo- date additional condition data reported by some DOTs. 21
