Transportation Asset Management Case Studies
Bridge Management Experiences of California, Florida, and South Dakota
California is responsible for the inspection and preservation of approximately 24,500 bridges. The California Department of Transportation (Caltrans) Division of Maintenance Office in Sacramento, with a staff of more than 140 bridge inspectors, structural engineers, and bridge management engineers, performs periodic inspections and maintenance for all of California's 12 districts. In addition, two independent city/county agencies perform bridge inspections on their own inventory. Of the 11 bridge management engineers in the Division of Maintenance Office, 2 develop software, 2 run bridge management programs in Pontis®, 1 enters data, and 6 monitor all ongoing projects.
All the information necessary to manage the integrity of California's bridge infrastructure is contained in a single database with sharing features achieved using the Pontis® data structure (figure 2). This interoperable database design eliminates the need to move information from one component to the other. Additional tables are linked to the Pontis® structure for various mission critical activities such as project tracking, maintenance recommendations, detailed fracture critical, scour and load rating information, and postearthquake inspection activities.
|Figure 2. Caltrans bridge management system schematic.|
Caltrans inspectors and engineers use three primary applications to access the different components of the database:
The overall security of the bridge management database is controlled at two levels. At the top level, all users are required to log into the Oracle engine, and their privileges are set to the appropriate level. At the form level, the SMART interface application (figure 3) assigns additional controls at the user login and validates the individual data items against the predefined values in the National Bridge Inspection Coding Guide. Inspectors, for example, can update any data item available to them through this SMART interface, but they cannot delete a bridge from the system. Using the Internet, district maintenance crews can access current recommendations for each bridge but are only allowed to update a single field, which indicates that a work item has been completed.
|Figure 3. Caltrans SMART interface.|
Bridge Inspections Using SMART
Bridge inspectors use SMART, a custom inspection collection and report generation software, which has a thin-client (Web-based) interface that allows inspectors to access the database from a remote location.
Caltrans inspectors are required to be State-licensed civil engineers. The inspection teams are responsible for all biennial inspections as well as fracture critical and underwater inspections. The teams collect inventory data and condition information in the field on system-generated pre-inspection reports and enter the inspection results into an electronic format to comply with National Bridge Inspection (NBI) standards. Their inspections are based on the American Association of State Highway and Transportation Officials "AASHTO Guide for Commonly Recognized (CoRe) Structural Elements" and custom developed elements that provide information on the condition of each element on the bridge. The information includes detailed fracture critical findings, load rating information, photos, and commentary for each structure in the bridge inventory. All textual as well as graphic information from these statewide inspections is then entered into the centralized bridge management database. Bridge inspectors use SMART, a custom inspection collection and report generation software, which has a thin-client (Web-based) interface that allows inspectors to access the database from a remote location.
The bridge information entered into the database through the inspection process is ultimately presented in a bridge inspection report. The inspection team is responsible for the inspection report and for making recommendations for preservation actions based on their findings in the field. The bridge inspection report documents the current condition of the bridge and all recommended work for that structure. This inspection report is the primary means of conveying the results of the inspection to the bridge owners.
In addition to the bridge report, the bridge management database is used to generate various lists and reports for district maintenance crews, project planners, Caltrans management, and the California Transportation Commission.
Project Prioritization Using Pontis®
The bridge management staff uses the Pontis® Bridge Management System to perform deterioration modeling and project prioritization. Within the Caltrans Division of Maintenance Office, the Office of Structure Maintenance and Investigation has the primary role for determining scope and priority for all bridge maintenance and preservation projects.
Bridge management engineers review and prioritize the needs identified by the inspectors. Projects are designed to minimize impacts to traffic and to maximize improvements with the funds available. Improvement projects involving, for example, new alignment or bridge widening, are initiated by the Caltrans Office of Planning along with Regional Transportation Planning Organizations.
These recommendations from all over the State are prioritized and validated by the Office of Structure Maintenance and Investigation against the project recommended priority list generated by Pontis® (figure 4). Bridge projects generated are manually coordinated with pavement management system projects, which is done through data extraction of projects from the bridge management database. Bridge managers use the comparison to coordinate the scheduling of projects. In some cases, Caltrans has operated using a Corridor Maintenance Policy, where segments of highways with a variety of maintenance needs such as bridge, roadway, landscaping, and drainage are publicized for full or substantial closure prior to performing the necessary work.
|Bridge ID||Feature Intersected||Year||Predom. Action||Predom. Object||Cost ($)||Benefit ($)||BCR|
|24 0228R||STOCKTON, 34TH,35TH, & T||2007||Rehab Elem||Other Bridge Railing||10,894||127,237||11.68|
|57 0551F||SIGN STRUCTURE||2007||Rehab Elem||Other Bridge Railing||9,351||106,703||11.41|
|57 0772||ROUTE 67||2007||Rehab Elem||Other Bridge Railing||7,042||78,991||11.22|
|24 0289L||UP,BNSF,SCRTDLRT,REDDING||2007||Rehab Elem||Other Bridge Railing||9,144||101,447||11.09|
|24 0069R||UP RR,BNSF,AMTRAK, I ST||2007||Rehab Elem||Other Bridge Railing||30,159||331,653||11.00|
|57 0713R||SAN LUIS REY RIVER||2007||Min Repair||Pourable Joint Seal||6,802||74,562||10.96|
|57 0568L||MTDB,BNSF,AMTRAK,15,PAC||2007||Rehab Elem||Other Bridge Railing||5,671||62,018||10.94|
|17 0070||ROUTE 80||2007||Rehab Elem||Other Bridge Railing||6,758||72,502||10.73|
|25 0099||SOUTH FORK AMERICAN RIV||2007||Ovly Deck||R/Conc Approach Slab||6,869||70,879||10.32|
|57 0001L||SAN MATEO CREEK||2007||Min Repair||Pourable Joint Seal||5,933||59,279||9.99|
Figure 4. Pontis® work candidate priority list.
The Division of Maintenance Office has adopted the bridge health index as one performance measure toward its goal of preserving the bridge inventory. The health index is a single number indicator of the structural health of the bridge. This indicator is expressed as a percentage value from 0 percent to 100 percent, corresponding to the worst and best possible conditions, respectively. The health index is calculated in Pontis® as a function of the fractional distribution of the bridge's element-level information across the range of their applicable condition states. Caltrans has begun an incentive program to encourage all districts to aim for a higher overall bridge health index.
Project Archiving Using BIRIS
California maintains a complete image archive of all bridge "as-built" plans, bridge reports, photos, and other significant correspondence in the bridge database. This information is scanned and indexed into the database by a staff specifically trained for this task. The images archived in the database are accessed using BIRIS, a Web application product developed specifically for Caltrans.
California maintains a complete image archive of all bridge "as-built" plans, bridge reports, photos, and other significant correspondence in the bridge database.
The database archive also contains
- Information on projects accomplished by State crews
- Completed State crew maintenance activities that are scheduled and performed based on recommendations by inspectors (documented in the database by the particular district crew performing the work via a custom developed Web page)
- Minor and major rehabilitation projects completed by contractors.
Caltrans enjoys effective management of its entire bridge inventory because the bridge management data are held in a single large database that is accessible to all users through Pontis® programming tools.
|Bidwell Bar Bridge at Lake Oroville, CA|