County Bridge Inspection. IACC Conference Presented by: Michael L. McCool, PE Bridge Department Manager Beam, Longest and Neff, LLC

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1 County Bridge Inspection Road Scholar Core Course # 9: Bridge Basics IACC Conference Presented by: Michael L. McCool, PE Bridge Department Manager Beam, Longest and Neff, LLC

2 Topics National Bridge Inspection Program Indiana Inspection Program LPA Guidance Document Types of Inspections Load Ratings QA/QC Eligibility for Federal Funds

3 National Bridge Inspection Program County Bridge Inspection Silver Bridge Disaster December 15, 1967 Point Pleasant, WV Eyebar-Chain Suspension Bridge Brought on the Federal Highway Act of 1968 which established a national bridge inspection standard

4 National Bridge Inspection Program County Bridge Inspection Mianus River Bridge June 28, 1983 Greenwich, CT Pin and Hinge Bridge Brought on the Inspection of Fracture Critical Bridge Members

5 National Bridge Inspection Program County Bridge Inspection Schoharie Creek Bridge April 5, 1987 Fort Hunter, NY Approximate 50 year flood with snow melt Brought on the technical advisory Scour at Bridges

6 National Bridge Inspection Program County Bridge Inspection I-35W August 1, 2007 Minneapolis, MN Steel Deck Truss Brought on the publication Load Rating Guidance and Examples For Bolted and Riveted Gusset Plates in Truss Bridges

7 National Bridge Inspection Program County Bridge Inspection Many of these collapses could not have been prevented by the inspection standards at the time. Real world examples of what can happen if critical areas of bridges are either not inspected or if critical findings are not followed up on.

8 Indiana Bridge Inspection Program County Bridge Inspection Purpose of the Bridge Inspection program is threefold: Ensure public safety Provide for the efficient use of resources in maintaining the serviceability of Indiana s bridges and small structures Comply with all federal and state laws, rules, and policies Bridge Inspections are required on all bridges meeting the National Bridge Inspection Standards (NBIS) definition of a bridge (Spans > 20 feet).

9 LPA Guidance Document The Role of the Employee in Responsible Charge (ERC) in Bridge Inspections Consultant Selection LPA-Consultant Bridge Inspection Contract Bridge Inspection Schedule Scour Monitoring Load Posting Signs Critical Findings New Bridges Bridge Files

10 LPA Guidance Document Chapter 1 ERC for County Bridge Inspections. County Bridge Inspection Managing the LPA s County Bridge Inspection Program. Ensuring timely inspections and reports. Reviewing and submitting related invoices. Submitting a Bridge Inspection Quarterly Report. Ensuring any and all required actions are completed as directed in the INDOT Bridge Inspection Manual and as described in this chapter. ERC s for Bridge Inspection are required to attend INDOT s Bridge Inspection Training Class.

11 LPA Guidance Document Chapter 13 County Bridge Inspection Map 21 legislation includes an Element Level Inspection requirement for bridges on the NHS. This chapter in the LPA Guidance Document does not in any way supersede the Bridge Inspection Manual (BIM). Help ensure all requirements in the BIM are fulfilled without exception. Failure of the LPA to comply with the National Bridge Inspection Program (NBIS) puts the LPA and INDOT at risk of losing all or a portion of their federal funds.

12 LPA Guidance Document Chapter 13 ERC Responsibilities Primary point of contact for LPA. County Bridge Inspection Responsible for ensuring a new Bridge Inspection Contract is in place prior to the expiration of the previous contract. Creation and advertisement of a Request for Proposals (RFP). Ensures the consultant selection process adheres to all Federal and State regulations and requirements. The process for initiating a new LPA Consultant Bridge Inspection Contract should begin approximately one year prior to the expiration of the current Bridge Inspection Contract.

13 LPA Guidance Document Chapter 13 County Bridge Inspection Bridge inspections shall be maintained on schedule and completed no later than the end of the month of the scheduled inspection month. Important to note: Late inspections do not change the schedule of any future inspections. There are possible penalties for late inspections. Penalties may include but are not limited to: Losing part or all of the federal funds provided within the inspection contract. Losing part or all of federal funds for other projects, etc.

14 LPA Guidance Document Chapter 13 County Bridge Inspection LPA s consultant is required to develop a Scour Monitor Plan of Action for all scour critical bridges. Responsibility of the LPA / ERC Know the plan. Know responsibilities outlined in the plan. Ensure the plan is followed during flood events. Part 4, Section 7.4 of INDOT BIM

15 LPA Guidance Document Chapter 13 Each bridge shall be load rated. County Bridge Inspection Load ratings shall be stamped by a Professional Engineer (PE). Uploaded into BIAS. Remain on file until rating condition changes. Revised rating warrants a new evaluation by PE. Part 3 of INDOT BIM

16 LPA Guidance Document Chapter 13 County Bridge Inspection Responsibility of the LPA to install and maintain load posting signs. Install and maintain permanent load posting signs in accordance with the load posting recommendations made by the inspection consultant within 90 days. ERC or consultant is responsible to upload photos with a date/time stamp taken from both sides of the bridge into INDOT s BIAS database. Bridge Inspector to notify ERC and Bridge Inspection Program Manager of the Critical Finding which will be recorded and monitored till closed out.

17 LPA Guidance Document Chapter 13 County Bridge Inspection Consultant is responsible for communicating any and all critical findings immediately to the following: ERC INDOT Bridge Inspection Program Manger ERC is responsible to ensure these findings are acted upon within 30 days from notification. Critical Deficiency is a situation that could cause the failure of all or part of the bridge, or a serious traffic safety hazard if not addressed immediately. Actions could be immediate repairs, closing the bridge or additional inspection.

18 LPA Guidance Document Chapter 13 County Bridge Inspection LPA s responsibility for developing and maintaining complete documentation of all aspects of bridge inspection for each bridge. Records must be made readily available to INDOT and FHWA upon request and shall be maintained for the life of the bridge and kept current in BIAS. Failure to maintain adequate bridge files puts the LPA at risk of failure to comply with the NBIS.

19 Types of Inspections Initial Inspections Routine Inspections Fracture Critical Inspections Underwater Inspections Special Inspections Damage Inspections Small Structure Inspections

20 Initial Inspections Baseline inspection. New bridge. After a major rehabilitation. Fully documented inspection. Use bridge plans to determine basic data for entry into BIAS. Required within 90 days of opening of bridge.

21 Initial Inspections Newly discovered bridges not previously inventoried. Bridge plans may not be available. Inspectors evaluate the bridge and decide what other foreseeable inspections will be required throughout its life, including Fracture Critical, Special, or Underwater Inspections.

22 Routine Inspections Regularly scheduled inspections. Consisting of observations and/or measurements needed to determine the physical and functional condition of the bridge. Identify any changes from previously recorded conditions. Routine Inspection ensures that the bridge continues to satisfy present service requirements.

23 Fracture Critical Inspections Regularly scheduled inspections. Examine the fracture critical members or member components of a bridge. Unique Qualifications of Inspection Team Leader. Completion of NHI Fracture Critical Class.

24 Definition of a Fracture Critical Member The FHWA and Indiana Bridge Inspection Manual (BIM), Part 4 - Chapter definition: A steel member in tension, or with a tension element, whose failure would probably cause a portion of, or the entire bridge to collapse. Steel member or portions of the member must be in tension (inclusive of tensile, shear, flexure, torsion or stress reversal forces). Must have no load path redundancy (i.e. less than three primary load carrying members).

25 What Members are Fracture Critical? County Bridge Inspection Rule of Thumb for Tension Rule of Thumb for Compression * Must verify forces with Load Rating

26 What Connections are Fracture Critical? Fracture Critical Connections If a Fracture Critical Member is present It is a Fracture Critical Connection

27 What Members are Fracture Critical (Through Girder)? Tension Zones Floorbeams Connections (Inside)

28 Fracture Critical Field Inspection Requirements Take measurements which will allow a load rating to be performed (with deterioration quantified). ALL fracture critical members, connections and components must be inspected hands-on (arm s length). Members, connections and components must be clean prior to the inspection.

29 Why Clean the Members and Components? Typical Truss Bearing with dirt and debris Crack at gusset plate of bearing

30 Underwater Inspections Mandated by the FHWA on routine intervals for bridges with substructure units in water. Most problems that occur under water do not become visible from the surface until they are critical. Bridges with substructure units in water must be inspected to ensure they are sound.

31 Underwater Inspections Underwater Inspections are called for if scour and the condition of elements below water cannot be assessed because: At the lowest flow during the year, the water is too deep. The current is too fast. The channel bottom is too soft for safe wading.

32 Special Inspections Scheduled to examine a portion of a bridge in more detail or at a greater frequency than is standard for Routine. Provide follow-up after a Routine, Damage, or Initial. Required for complex structures which require a more comprehensive inspection than is possible in a Routine Inspection. Components to be inspected at arm s length.

33 Special Inspections Details and bridges that require a Special Inspection include the following: Cover plates Fatigue category E and E details Hangers of all types Hinge or pin connections Tri-axial Constraint details Known defects or damages severe enough to warrant extra scrutiny Steel box girders Timber-covered bridges Railroad flat car bridges

34 Damage Inspections Unscheduled inspection. Assess structural damage resulting from environmental factors or human actions. Flood damage, fire damage, barge impact, and vehicle impact are examples of events that may call for a Damage Inspection.

35 Small Structure Inspections Bridges and culverts with spans greater than 4 feet and less than or equal to 20 feet. Regularly scheduled inspections. Observations and measurements needed to determine the physical and functional condition of the structure. Identify any changes from previously recorded conditions. Ensures that the structure continues to satisfy present service requirements.

36 Load Ratings All state, county, toll road, and local agency bridges shall have a load rating performed. Perform the load rating based on the current findings. Inspection Consultants may obtain the existing load ratings from the previous Inspection. By re-using the existing load rating, the Inspection Team Leader accepts the responsibility and liability for the load rating and relieves the liability of the load rating from the previous Inspection Consultant.

37 Why QC/QA Procedures? To help ensure: Accuracy Consistency A Quality Product Public Safety Maintenance and Repairs Prioritization of Recommended Work Identification of Training needs Part 2 Indiana Bridge Inspection Manual

38 Why QC/QA Procedures? It is a federal requirement ( 23 CFR (g) ) 23 CFR (g) Quality Control and Quality Assurance requires each state to assure that systematic Quality Control (QC) and Quality Assurance (QA) procedures are being used to maintain a high degree of accuracy and consistency in the inspection program Without QC/QA procedures in place, FHWA would find INDOT non-compliant QC Internal Review QA External Review

39 Quality Control Procedures Internal review process Focus on at-risk bridges Condition Ratings of 4 or less Field and office reviews Time added is approximately 2 days per inventory Designated Quality Control Officer Consultant direct supervisor or a program manager Firms w/o active 2 nd team leader shall use another firm Not the team leader of original inspection team

40 Quality Assurance Procedures County Bridge Inspection INDOT or INDOT s assigned organization will be the quality assurance officer Ensure adherence to FHWA and INDOT criteria Reviews include: Independent Oversight Bridge File Load Rating Verification

41 Quality Assurance Procedures Independent Oversight Review County Bridge Inspection Ensure consistency of condition ratings Ensures QC efforts are equally effective Independent field inspection by QAO Performed within 6 months of team leader s inspection Bridge File Review INDOT Database Manager selects 10 bridge files reviewed per quarter Files reviewed for accuracy and completeness

42 Quality Assurance Procedures Load Rating Verification Review INDOT Load Rating Engineer selects 10 bridges reviewed per quarter County Bridge Inspection Files reviewed for accuracy and completeness Files must contain the summary sheet from the load rating All supporting computations must include a clear statement of all assumptions used in calculating the load rating For computer modeling, input data files shall be included in the file

43 Quality Assurance Closeout Independent Oversite, Bridge File and Load Rating Verification Review reports discussed with Bridge Inspection Program Manager. Annual report to summarize findings. Corrective actions to inventory data may be necessary. Additional Training may be required.

44 Eligibility for Federal Funds To be eligible for Replacement or Rehabilitation Funds, Bridges must meet following criteria: Greater than 20 feet in length and; Structural Deficient or Functionally Obsolete and; 10 Year Rule Cannot have been replaced or rehabilitated within last 10 years, regardless of funding source and; Sufficiency Rating : 80: 50: Not Eligible Rehabilitation Replacement

45 Eligibility for Federal Funds Structurally Deficient: Deck, Superstructure, Substructure or Culvert Condition Rating of 4 (Poor) or less. or: Structural Condition or Waterway Adequacy Appraisal Rating of 2 (Basically Intolerable Requiring High Priority of Replacement).

46 Eligibility for Federal Funds Functionally Obsolete: Deck Geometry, Underclearance, or Approach Roadway Alignment Appraisal Rating of 3 (Basically Intolerable Requiring High Priority of Corrective Action). or: Structural Condition or Waterway Adequacy Appraisal Rating of 3 (Basically Intolerable Requiring High Priority of Corrective Action).

47 Eligibility for Federal Funds Sufficiency Rating 15% 55% Structural Adequacy and Safety Load carrying ability based on what it 55% was designed for 30% (Deterioration) 30% Serviceability and Functional Obsolescence - Geometry Criteria based on current standards 15% Essentiality for Public Use Detour Length and Strategic Highway Network (STRAHNET) ( - ) Special Reductions Long Detours, Specialty Bridges and Traffic Safety Features

48 Questions? IACC Conference Presented by: Michael L. McCool, PE Bridge Department Manager Beam, Longest and Neff, LLC