21st South Seismic Station Upgrades: Instrumentation and Structural Health Monitoring

Utah Department of Transportation's (UDOT’s) 21st South Seismic Station was established in the early 2000’s in collaboration with UDOT, Utah State University (USU), University of Utah Seismograph Stations (UUSS), Brigham Young University (BYU), and the U.S. Geological Survey (USGS). In 2008 some station repairs, upgrades, and other changes took place during the adjacent UTA TRAX line construction. The UUSS monitors and maintains one surface acceleration sensor at the site as Station 7208 in the UUSS network. The rest of the site instrumentation is monitored and maintained by UDOT with some assistance from USU and UUSS. Instrumentation being actively monitored at the site includes two surface acceleration sensors, nine bridge acceleration sensors attached to flyover structure C-846, and five downhole acceleration sensors at depths of 25 to 400 feet. This represents a total of 39 channels of horizontal and vertical acceleration data. The associated onsite data recorders have been configured to record structural and ground accelerations during a major earthquake. While the majority of the station equipment is working well, some key equipment is beginning to have significant problems and is in need of repair or replacement. The main example of this condition is that the seismic data recorders are showing signs of aging or wear, with various error messages appearing and some components failing. These recorders can no longer be serviced by the manufacturer. Newer seismic data recorders are available and have additional functionality. At the same time, there is interest by USU to conduct structural health monitoring of structure C-846 using the existing bridge acceleration sensors and proposed temperature sensors that could be attached to the bridge. The major objectives are to:p reserve the readiness of the seismic station for accurately recording strong motion of the bridge and the downhole array during a major earthquake for at least the next 10 years; and conduct meaningful structural health monitoring using existing and new sensors on the bridge, with clearlyidentified research objectives that would benefit UDOT and academia. Major Tasks are: Task 1. Establish a common vision and develop a plan to maintain UDOT’s 21st South Seismic Station. (a) Hold a meeting with interested agencies (UDOT, USU, USGS, UUSS) to determine individual data needs (USU to contact agencies as needed prior to meeting to prepare and bring preliminary proposal of following items which will be fine-tuned and finalized at meeting); (i) Define roles and responsibilities of all partners; (ii) Define an action plan for all partners if a strong motion event occurs; (iii) Create an inventory of all the existing equipment (recorders, sensors, etc.) and describe the capabilities of each; include a matrix outline, photographs, diagrams, etc. to support the effort; (iv) Identify the equipment gaps to meet the needs of the partners; describe the gaps in the current capabilities to understand why additional equipment (sensors) are needed; (v) Develop a plan for structural health monitoring of the bridge include any additional equipment needed for this effort (current equipment gap); (vi) Determine what data will be collected and how each agency will access and use the data; and (vii) Determine equipment needs based on the defined data requested and recommended structural health monitoring. Task 2. Evaluate the condition of the existing equipment (seismic data recorders, sensor channels, etc.); this includes evaluating the two downhole sensors and a surface sensor that have erratic signals. Task 3. Prepare a cost estimate for replacing, updating and adding additional equipment including labor and installation costs. Task 4. Develop an implementation plan for Phase I, Task 3 with a detailed schedule. Task 5. Create a report outlining Phase I Tasks 1 through 4. Task 6. Purchase and install equipment as described in the implementation plan (amount depends on allotted funding but anticipated equipment will include at least a 36 channel data acquisition system to be installed in the shed. In addition to the data acquisition system, an array of thermos-couples will be installed on the bridge to determine bridge temperatures thru the thickness of the deck and transversely across the bridge. It is anticipated that this array will include approximately 16 channels of temperature data.) (a) Collect initial data from installed instrumentation and communication solutions. Task 7. Update the seismic station inventory and operations manual. Task 8. Develop a plan for long term station monitoring and future maintenance along with an associated cost estimate for the effort. Task 9. Develop agreements between partners to manage and maintain the seismic station. Task 10. Create Phase I summary report with recommendations for future upgrades & monitoring.

    Language

    • English

    Project

    • Status: Active
    • Funding: $45000
    • Contract Numbers:

      168533

    • Sponsor Organizations:

      Utah Department of Transportation

      4501 South 2700 West
      Project Development
      Salt Lake City, UT  United States  84114-8380
    • Managing Organizations:

      Utah Department of Transportation

      4501 South 2700 West
      Project Development
      Salt Lake City, UT  United States  84114-8380
    • Project Managers:

      Hales, Thomas

    • Performing Organizations:

      Utah State University, Logan

      Civil and Environmental Engineering Department
      Logan, UT  United States  84332
    • Principal Investigators:

      Halling, Marvin

    • Start Date: 20151230
    • Expected Completion Date: 20170331
    • Actual Completion Date: 0

    Subject/Index Terms

    Filing Info

    • Accession Number: 01590772
    • Record Type: Research project
    • Source Agency: Utah Department of Transportation
    • Contract Numbers: 168533
    • Files: RiP, STATEDOT
    • Created Date: Feb 22 2016 2:06PM