Click for next page ( 7

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 6
6 CHAPTER 1 Background on Bridge Maintenance Programs at U.S. Departments of Transportation The database system developed under this project is crews, and as pay items for contract maintenance. Some DOTs designed to be compatible with existing practices in bridge employ multiple numbering systems. Work by DOT crews maintenance of U.S. Departments of Transportation (DOTs). may be reported in one numbering system for crew activity To ensure compatibility, current practices in programs for reports and in another numbering system for a maintenance bridge maintenance were reviewed. Common features in main- management system. tenance work activities and work reporting were noted. These At most DOTs, there is greater detail in data systems that common features became the basis in formation of a national record crew activities or contract pay items, and greater aggre- database for bridge maintenance work. The review exam- gation in management systems for maintenance programs. ined the type and scope of work activities in bridge main- Both systems are useful. Detail in crew activities and pay items tenance. The review produced a glossary of terms in bridge allows simple computation of costs. Aggregation into mainte- maintenance. nance operations provides an overview of maintenance pro- gram scope and accomplishment. Scope of Bridge Maintenance Bridge Maintenance Scope Bridge maintenance can be defined in terms of policy state- and Definition ments, lists of actions, budget status and the capabilities of DOTs' maintenance data systems. DOTs recognize mainte- Definitions of bridge maintenance are collected from nance as distinct from new construction, replacement of struc- AASHTO (1, 12), published materials of state DOTs, and tures, and major rehabilitation of structures. Replacement or NCHRP reports. Bridge maintenance can be defined by at modification of portions of bridges may be maintenance if least the following four means: projects are small and have a short duration. Larger projects are construction, rather than maintenance. Emergency work, usu- 1. Policies: Descriptive concepts of the kinds of work and ally in response to accidents or extreme events, is classified as outcomes that are maintenance. maintenance and can entail significant, temporary modifica- 2. Actions: Maintenance denoted by lists of maintenance tions to bridges. 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. DOT Maintenance Actions 4. Data: Maintenance identified and perhaps limited by Most DOTs recognize bridge components as objects of the capabilities of data systems used in maintenance maintenance actions. Maintenance actions at most DOTs operations. distinguish construction materials (repair steel versus repair concrete) and types of work (patch beam versus straighten Maintenance Defined By Policies beam). Some DOTs recognize separate maintenance actions for different types or forms of bridge component. Policy-level definitions of maintenance are obtained from Numbering systems for maintenance actions exist in three AASHTO, FHWA, and state transportation agencies. forms: as maintenance operation items used by maintenance AASHTO's guide (13) defines maintenance as any activity management systems, as action items used by maintenance other than new construction. AASHTO's maintenance manual

OCR for page 6
7 (2) more narrowly defines maintenance as routine upkeep and bridge reconstruction, and bridge replacement are not main- relatively small repairs that keep bridges in good condition. tenance. New construction is not maintenance. Maintenance actions include routine cleaning and painting as well as repairs and replacements of components. FHWA (33) recognizes these same activities as maintenance. Maintenance Defined by Lists of Actions NCHRP Report 131 on budgeting for highway maintenance A review of maintenance actions presented by AASHTO (30) defines maintenance as actions that preserve assets in their and by state DOTs reveals seven common operations in bridge as-constructed condition. This definition excludes improve- maintenance (Exhibit 1). ments to existing structures as well as new construction. State Most state DOTs identify maintenance actions in all oper- DOTs often define maintenance in a similar, narrow sense. ations shown in Exhibit 1 though terms vary among DOTs. Maintenance preserves bridges and can restore bridges to orig- Some DOTs identify minor repair and major repair rather inal condition. New construction and betterments--actions than repair and replace. Some DOTS describe betterments, that increase capacity or improve function of bridges--are instead of modify actions. Modify actions, within mainte- often excluded. nance programs, can include replacement of obsolete rail- California DOT maintenance manual (22) notes that, main- ings, extension to drain outlets, and relocation of bracing in tenance does not include reconstruction or improvements. truss portal frames. Some DOTs have separate categories for Idaho DOT (23) considers improvements part of maintenance. maintenance of movable spans, motion equipment, tunnels, Michigan DOT (6) notes that maintenance projects are of or other structural assets. short duration and have little impact on traffic operations. Montana DOT notes that (28) maintenance preserves the Maintenance Defined by Budgets originally intended use and function of bridges. Ohio DOT (37) notes that maintenance is intended to keep bridges in Budgets in transportation departments identify funds for original condition. Oregon DOT (20) identifies preserving, the maintenance division, contract maintenance, and equip- repairing, and restoring as maintenance. Texas DOT (21) ment and materials used in maintenance tasks. The federal identifies maintenance in three categories: routine, preven- Highway Bridge Program (HBP) program has an impact tive, and major. Texas' major maintenance includes bridge here. Bridge replacement or major rehabilitation projects replacement and bridge reconstruction. Washington State that are eligible for HBP funds are not maintenance. At the DOT (27) identifies cleaning and minor repairs as normal same time, projects that extend life of bridges are mainte- maintenance. nance and can be HBP-eligible. Eligible maintenance proj- Based on stated policies, cleaning and minor repairs are ects usually entail repairs, element replacements, or minor always maintenance. Repairs or replacements of components modifications. are often maintenance. Improvements achieved in small proj- From the perspective of DOTs' budgets, cleaning and other ects might be maintenance. Larger projects for improvement, routine upkeep are always maintenance. Repairs, component 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.

OCR for page 6
8 replacements, and minor modifications are usually mainte- bridge inspections and road surveys. A third category, updat- nance and may be eligible for federal HBP funds. Bridge ing, may be added. Updating is work to replace obsolete ele- replacement and major rehabilitations are not maintenance. ments such as bridge railings, when the replacement is per- formed as part of the maintenance program. DOTs use various Maintenance Defined by Data Systems names for these categories of maintenance. Terminology is addressed in Chapter 6. The capabilities of data systems can impose limits on the work that is tracked as maintenance. Maintenance data are Contract Maintenance the history of maintenance actions executed on bridges. Each bridge is presented to the maintenance database as an entity; Contracts for bridge maintenance work include site contracts as a complete set of descriptive and defining data. A bridge that deliver a fixed schedule of repairs at a fixed set of bridges, is presented as its National Bridge Inventory (NBI) record, open-ended contracts that provide specified maintenance its element-level model, its element-level condition data, etc. actions, and asset management contracts that provide a level of Maintenance actions are tied to individual bridges. The exis- service along a route (Table 1). Site contracts are construction tence and immutability of each bridge and its make-up are contracts that deliver a set of repairs or treatments at bridges. essential attributes. Projects that replace bridges or greatly alter Open-ended contracts offer a schedule of maintenance actions bridges are not maintenance, in this context, because they are that district managers can direct to bridges. Asset management not compatible with the basic organization of maintenance data. (AM) contracts place responsibility for both the identification of maintenance needs and the execution of work with the con- Maintenance Categories tractor. In AM contracts, DOTs make periodic inspections of Maintenance programs consist of two broad categories: cyclic assets to verify that the level of service is adequate. work and singular work. Cyclic work, which includes actions In bid processes, site contracts entail bidding on a fixed such as deck sweeping, is performed at set intervals. Singular schedule of items with fixed quantities. Open-ended contracts work, such as repair, is performed in response to deficient con- entail bidding on a fixed schedule of actions with estimated ditions. The categories reveal two distinct origins of mainte- quantities; quantities are estimated for the first years' work in nance projects. Cyclic work is performed in response to DOT the contract based on known maintenance needs. Asset Man- policy. Singular work is performed in response to inputs from agement contracts entail bidding on a schedule of actions and Table 1. Bridge maintenance contracting (14). DOT Contract Note 3-year duration, Standard maintenance actions and costs, Maximum Delaware Open-end contract amount. AM Maintenance action executed when requested by DOT. Florida Site Bridge rehabilitation, Bridge replacement. Michigan Site Capital scheduled maintenance, Capital preventive maintenance. Site Larger maintenance projects. An open-ended contract type using a construction task catalog of fixed Job Order prices. Suited to replacement-in-kind maintenance needs. New York Contracts that provide bid items, quantities and engineering design plans for one among a set of similar projects. Schedule of bid prices are Hybrid applied to additional, similar projects as quantities and engineering design become available. Small contracts are administered within districts. Larger projects go to Oregon Site OrDOT's central procurement. District-wide contracts having 3-year duration and renewed each year. Contracts funded at $2MM annually. Contracts have 95 bid items for Open-end both ordinary and preventive maintenance, and a mix of federal-eligible and non-eligible actions. Virginia Turnkey asset management (TAM) contracts are used for operations and AM minor repairs along interstate routes. Consultant design services are available to VaDOT districts through Design three, open-ended, regional contracts. An open-ended contract type. Used for maintenance actions at ferry Washington Job Order terminals.