Monitoring Scour Critical Bridges (2009)

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66 Appendix A contains a blank copy of the synthesis survey that was sent to state departments of transportation in the United States. Detailed results of the survey can be found in Appendix C. APPENDIX A Survey

67 NCHRP SYNTHESIS TOPIC 36-02 PRACTICES FOR MONITORING SCOUR CRITICAL BRIDGES PURPOSE OF THIS SYNTHESIS: In the United States, there are 26,000 scour critical bridges, so me of which are m onitored by fixed instru me ntation. Following th e approxi ma tely 100 of these bridges have been instru me nted for scour m easure me nts. Often these bridges are instrum ented because the scour estim ates seem overly conservative, and it is prudent to observe scour activity during flood events before spending resources on other types of counterm easures. For other bridges scheduled to be replaced, m onitoring (prior to replacem ent) is a cost-effective alternative to ensure the safety of the traveling public. Valuable field data are often accum ulated fro m instrum ente d bridges, and so me of these bridges have been m onitored for mo re than eight years. This data—and the exploration and evaluation of it—will prove useful in the im provem ent of technologies a ssociated with both predicting and m onitoring bridge scour. The focus of this study is fixed m onitoring instru me ntation. This synthesis will serve to docum ent the success or failure of th e various scour m onitors that have been deployed and to obtain ideas that can help im prove the reliability of existing m onitoring equipm ent. This synthesis will also serve as a foundation for the developm ent of a national database that will serve as a valu a bl e resource to engineers and researchers for assessing the accuracy of various scour estim ating procedures currently in use. m unicipal to the international level. Allow approxim ately one and one-half hours to com plete this questionnaire. Additionally, those respondents who believe their scour monitoring project would make a good case study are invited to indicate their willingness to contribute detailed information about their projects. They will be contacted individually by the researcher to obtain the case study inform ation. Transportation Research Board, and others, with the goal of assisting in the developm ent and im plem entation of scour m onitorin g program s. It is a rare opportunity to do substantive research in the field of scour m onitoring instru me ntation. This field is v ital to the health of the nation’s transportation system , and the results from this project will provide a m eans to disse mi nate the experience of engineers fro m around the world in a straightforward fashion. Kindly answer the following questions to the best of your knowledge. All departm ents within your agency that have significant experience with scour m onitoring instru me ntation should be given the opportunity to co mme nt or answer survey questions that pertain to his or her expertise. Additional copies of this survey ma y be ma de as needed. If multiple bridges are or were monitored by your agency, please choose from the following two options: (1) complete Sections 3 through 7 for each bridge , or (2) select one bridge for each category of instrumentation employed and complete Sections 3 through 7. If you select Option 2, please attach a list that includes the names of the bridges being monitored and the type of instrumentation. If providing an exact answer will require mo re tim e than you can allow, please offer your best estim ate or leave that question blank. If you have any questions regarding the proper interpretation of this survey, do not hesitate to call or e-m ail me . We appreciate your support and thank you for your tim e and effort. Wh en you have co mp leted this survey, please return it by March 4, 2005 by any convenient m eans to: Beatrice E. Hunt, PE Hardesty & Hanover, LLP 1501 Broadway New York, NY 10036, USA TEL: 212-944-1150 FAX: 212-391-0297 E-m ail: bhunt@hardesty-hanover.com If you would like more space to answer a question, please feel free to include an attachment and reference the question number ( s ) in the survey. Note that the blank lines in the electronic survey will expand automatically to allow additional space. successful completion of NCHRP Project 21-03 Instrumentation for Measuring Scour at Bridge Piers and Abutments, The purpose of this questionnaire is to collect specific information on fixed scour monitors from sources ranging from the The results of this synthesis will be shared and distributed through AASHTO, the Federal Highway Administration, the

68 City State Country City State Zip Code Country Street Address Section 1 Respondent Information 1.1 Agency/Organization 1.2 Address 1.3 Contact Name 1.4 Department/Group 1.5 Job Title 1.6 Telephone 1.7 Fax 1.8 E-mail 1.9 Type of Agency/Organization Federal Agency County Agency State/Provincial Agency Municipal Agency Engineering/Design/Planning Firm Construction Company Monitoring System Vendor Professional/Trade Organization Other: Section 2 General 2.1 Does or has your agency/organization used instrumentation for scour monitoring? Yes No 2.2 If yes, what type(s) of scour monitoring have you employed? (Check all that apply.) Portable Instrumentation Fixed Instrumentation If you have not used fixed scour monitoring instrumentation, please respond to Questions 2.3, 2.4, 5.14, 8.1, and 9.8 only. If you have used fixed instrumentation, please proceed to Sections 3 through 9. 2.3 If you have not used fixed instrumentation for scour monitoring, are there particular problems/limitations why you have chosen not to use this technology? 2.4 What innovations/advancements would be beneficial for you to consider using fixed scour monitoring instrumentation? Section 3 Specific Bridge Information If multiple bridges are or were monitored by your agency, please choose from the following two options: (1) complete Sections 3 through 7 for each bridge, or (2) select one bridge for each category of instrumentation employed and complete Sections 3 through 7. If you select Option 2, please attach a list that includes the names of the bridges being monitored and the type of instrumentation. 3.1 Bridge Name 3.2 Route Number 3.3 Average Daily Traffic (ADT) 3.4 Bridge Location 3.5 Name of Waterway 3.6 Year Built Year Rebuilt (if applicable) 3.7 Bridge Identification Number (BIN) 3.8 Who owns the bridge? 3.9 Who maintains the bridge? 3.10 What is the total length of the bridge? ft m 3.11 What type of structure is it? (Check all that apply.) Fixed Bridge Movable Bridge Highway Bridge Railroad Bridge Culvert Bulkhead Wharf/Fishing Pier Other:

69 3.12 What types of fixed scour monitors were/are installed at the bridge? (Check all that apply and indicate the number for each type of monitor after the name.) Sonars: Magnetic Sliding Collars: Tilt Sensors: Briscos: Float-out Transmitters: Vibration Sensors: Sounding Rods: Buried/Driven Rods: Piezoelectric Polymer Film: Others: 3.13 Please list the name and contact information of the vendor who provided the fixed monitors. 3.14 Why were scour monitors installed at this bridge? (Check all that apply.) Scour critical rating Bridge to be replaced in about years Research project for: Others: 3.15 If applicable, what are the ratings for NBIS Items 60 and 113 for the substructure units being monitored? Item 60: Item 113: Not certain 3.16 Has the monitoring data obtained been useful for changes or verification of the bridge scour ratings? No Yes; specify: 3.17 What is the foundation type? Piles Spread Footings Drilled Shafts Unknown 3.18 Is the foundation depth known? Yes—as-built depths Yes—design depths Unknown 3.19 What part of the structure is being monitored? (Check all that apply.) Pier(s) Number of piers: No. of monitors per pier: Abutment(s) Number of abutments: No. of monitors per abutment: Others: Section 4 Site Conditions 4.1 Is the waterway riverine or tidal? Riverine Tidal 4.2 What is the flow habit of the waterway? Ephemeral Intermittent Perennial but flashy Perennial 4.3 Are any of the conditions listed below present at the site? (Check all that apply.) Debris loading Extreme temperatures Sediment loading Ice flows Air entrainment High velocity flows 4.4 Is there a history of scour at the site? Yes No Unknown 4.5 What is the average water depth in the main channel? <10 ft (<3 m) 10–30 ft (3.1–9.1 m) 31–50 ft (9.2–15.2 m) 51–75 ft (15.3–22.9 m) 76–100 ft (23–30.5 m) >100 ft (>30.5 m) Unknown 4.6 Major flood events (if any) since the monitors were installed: Date(s) of Flood (Indicate dd/mm/yy) Maximum Discharge (Indicate cfs or cms) Return Interval (Indicate year) Approx. Velocity* (Indicate fps or mps) *Approaching pier/abutment 4.7 What are the subsurface conditions in the area of the bridge? (Check all that apply.) Clay Fine Sand/Silt Coarse/Medium Sand Gravel Cobbles Organics Concrete Riprap Bedrock; type of rock: Others: 4.8 Are there borings and/or other soil/rock data available for this location? No Yes; describe: Others:

70 Section 5 Design and Installation 5.1 Describe the location of the fixed monitors with reference to the bridge. (Check all that apply.) Upstream Buried; feet/meters away from bridge substructure Downstream Mounted on substructure Others: 5.2 When were the monitors installed (example: Month/YYYY)? 5.3 What were the costs of installation? (Include all available costs and specify type of currency.) Materials: Labor: Per monitor location: Total: 5.4 What type of contract was the scour monitoring system installed under—bridge rehabilitation, stand-alone project for scour monitoring, or some other type of contract? (Check all that apply.) Bridge Rehabilitation Scour Countermeasures Emergency Scour USGS Research Project FHWA Demonstration Project 97 (DP-97) Research: Others: 5.5 What factors contributed to the decision to use fixed scour monitors for this location? For Questions 5.6 to 5.8 below, please check all groups that apply. 5.6 Who designed the scour monitoring system? Contractor In-House Staff—Department/Group Name: Consultant Monitoring System Vendor Others: 5.7 Who manufactured the scour monitoring system? Contractor In-House Staff—Department/Group Name: Consultant Monitoring System Vendor Others: 5.8 What parties were involved in the installation of the scour monitoring system? Contractor In-House Staff—Department/Group Name: Consultant Monitoring System Vendor Others: 5.9 Do the monitors have an automated alarm system (automatic alert that sends a signal)? Yes No Yes—but currently not in use Not certain 5.10 If there is an automated alarm system, please list the agency/organization and department/group that is contacted when the automated system is activated: 5.11 If there is an automated alarm system, how are the responsible persons contacted? E-mail Fax Telephone Pager Others: 5.12 How is the fixed monitoring system powered? Solar power Commercial power Others: 5.13 If there are any other types of scour countermeasures (structural, hydraulic, etc.), monitoring equipment, or portable monitors utilized at the bridge, please list them: 5.14 Are other measurement instruments installed at the bridge? (Check all that apply and indicate the number installed for each type of device.) Water Stage Sensors Velocity Meters Inclinometers Water Quality Monitors Structural Monitors; specify: Temperature Sensors Wind Sensors Others: 5.15 If any instruments were checked in the previous question, indicate whether they are part of the scour monitoring system, and if known, the manufacturer. If “Others” was checked, please describe the type of instruments. 5.16 Does the monitoring system contain any special innovative features or materials? Please describe:

71 Section 6 Data Collection and Analysis 6.1 How often do the fixed monitors take readings? Every 30 min. Once hourly Daily Weekly Monthly When activated by: Others: 6.2 How often is the data collected and reviewed by a person(s)? Every 30 min. Once hourly Daily Weekly Monthly Others: 6.3 How often is the data collected and reviewed during emergency situations? Every 30 min. Once hourly Daily Weekly Monthly Others: 6.4 Please describe what is considered an emergency situation and the emergency protocol for this site. For example, is it a pre-determined data value, a major storm event, and/or a water surface elevation that would prompt an emergency response? Does the emergency response consist of lane/roadway segment/bridge closures and/or additional monitoring? 6.5 How is data downloaded or retrieved? (Check all that apply.) Automatically downloaded via telemetry to a base computer and retrieved at that computer Automatically downloaded via telemetry to a network and retrieved via internet connection Not automatic—downloaded by the person(s) monitoring the bridge 6.6 By which mode is the data downloaded? (Check all that apply.) Locally at the bridge site Via telephone landline (dial-up) Via cellular Via satellite Others: 6.7 Please list the agency/organization and department/group responsible for monitoring the bridge. 6.8 Is a continuous set of data available? Yes No Not certain 6.9 In what format is the data recorded? Text File Spreadsheet Database Others: 6.10 How is the data used, and what outputs are generated (i.e., graphs, data reduction, reports, design, and/or analysis)? Please describe: 6.11 Describe if the monitoring data has been useful in verifying scour predictions. 6.12 What is the scour rating of this bridge according to the FHWA National Bridge Scour Evaluation Program, FRA requirements for identification of scour critical bridges, or other systems? Low Risk Scour Susceptible Scour Critical Unknown Foundation Others: 6.13 Has an emergency Plan of Action, similar to that developed by FHWA, been established? Yes No Not certain Specify: 6.14 If applicable, has the information obtained from the monitoring been useful for the development or revisions to a Plan of Action? Please describe: 6.15 How were critical/emergency scour depths determined for the bridge? Please describe: 6.16 Are independent checks performed in order to confirm the validity of the readings from the fixed monitors? Examples of independent checks would be readings from portable monitors, diving inspections, or fathometric surveys. Please check the appropriate box and explain. Yes No Not certain 6.17 Has data been recorded during a hurricane or other extreme event? If you can provide these data, please indicate this in Section 9.2. Yes No Not certain

72 6.18 Have analyses and/or tests been performed for this site? (Check all that apply.) Hydraulic and Scour Analysis 1-D; 2-D; 3-D Hydraulic Computer Modeling Borings EFA Testing Pier Stability Analysis Physical Testing (i.e., flume tests); specify: Others: Section 7 Operation, Maintenance, Inspection, and Repairs 7.1 Is the monitoring system currently operational? (If partially operational, check “yes” and all that apply.) Yes No—needs repair No—monitors vandalized No—bridge not in service No—monitoring discontinued No—monitors salvaged No—insufficient funding Not certain—still in place Not certain Others: 7.2 Based on the response to Question 3.12, how many fixed monitors are still currently in operation? Sonars: Magnetic Sliding Collars: Tilt Sensors: Briscos: Float-out Transmitters: Vibration Sensors: Sounding Rods: Buried/Driven Rods: Piezoelectric Polymer Film: Others: 7.3 Have any of the following interfered with the operation of or caused damage to the fixed monitors? (Check all that apply.) Ice flows Debris Interruptions with solar power Corrosion/electrolysis Collisions (ships, etc.) Others: Vandalism; specify vandalized components: 7.4 Are there regularly scheduled maintenance and inspection procedures for the scour monitoring system? If so, please briefly describe the procedures. For example, indicate what parts are serviced and how often. Yes No Not certain 7.5 When maintaining or repairing the scour monitoring system, what is required to access the system? (Check all that apply.) Security Clearance Lane Closures Boat(s) Keys to Doors/Gates Others: For Questions 7.6 to 7.8 below, please check all groups that apply. 7.6 What parties are involved in the routine maintenance of the fixed scour monitors? Contractor In-House Staff—Department/Group Name: Consultant Monitoring System Vendor Others: 7.7 What parties are involved in the repair of the fixed scour monitors? Contractor In-House Staff—Department/Group Name: Consultant Monitoring System Vendor Others: 7.8 What parties are involved in the inspection of the fixed scour monitors? Contractor In-House Staff—Department/Group Name: Consultant Monitoring System Vendor Others: Section 8 Overall Experience, Comments, and Recommendations The purpose of this section is to gather the experience of the bridge owners in order to further the technology and practice of scour monitoring. Please give this section some thought and consideration. Using your feedback, we hope to discover more efficient and cost-effective scour monitoring solutions. 8.1 Do you plan to use additional fixed or portable scour monitors in the future? Yes No Not certain 8.2 Were any problems encountered during the installation of the scour monitoring systems? If so, please describe the problems and any solutions that were devised.

73 8.3 Please comment on the reliability and longevity of the scour monitoring systems, including all components such as the power delivery (solar panels, wiring, batteries, chargers, etc.), software, materials (steel, stainless steel, PVC, etc.), and hardware (nuts, bolts, anchor studs, washers, etc.). For example, how many repairs are needed per year and what types of repairs have been required? 8.4 Please comment on the costs of operation, maintenance, repair, and inspection with respect to the original installation costs. If you are able to list costs, please indicate the time period (i.e., yearly, since installation, etc). Were these additional costs anticipated? 8.5 Were there any additional problems or issues with the scour monitoring systems that were not mentioned in this survey? Were these problems unique to the structure geometry, soil, or waterway conditions? 8.6 What lessons have you learned with the fixed scour monitoring systems? 8.7 What benefits have you gained using fixed scour monitors? 8.8 What advancements do you think are important for the future of fixed scour monitoring technology? 8.9 How long do you intend to keep the data obtained from this scour monitoring project? Section 9 Request for Materials If you have any of the following materials and can submit them with the survey, or in the near future, please indicate so below. Submittals may be in any form that is convenient, electronic, or hard copies. 9.1 Sample data including any spreadsheets, graphs, and/or figures. Yes No 9.2 Sample data recorded during a hurricane/other extreme event, including any available storm data. Yes No Not applicable 9.3 Plans and specifications showing innovations to scour monitoring systems. Yes No Not applicable 9.4 Scour monitoring program write-ups including instructions and/or manuals. Yes No Not applicable 9.5 A Plan of Action manual, similar to that developed by FHWA, for the bridge(s). Yes No Not applicable 9.6 Are there any papers, reports, or case studies published or unpublished on this project(s)? Yes No Not applicable If a copy is not being submitted, please indicate how this material may be obtained: 9.7 Please list any additional materials you are submitting or recommended references: 9.8 If you know of any other fixed scour monitoring installations outside of your agency that are not DOT and/or documented in FHWA HEC-23, Bridge Scour and Stream Instability Countermeasures, would you please provide contact information on the bridge owner and if known, the structure name(s)? 9.9 If you believe your scour monitoring project would make a good case study and are willing to contribute detailed information about your project, please indicate so below. You will be contacted by the researcher to obtain the case study information. Yes No If there are any issues not covered in this survey that you would like to comment on, please feel free to add sheets as necessary. Please respond by March 4, 2005 THANK YOU FOR SUPPORTING THIS IMPORTANT EFFORT