Structures Solutions. Second Strategic Highway Research Program (SHRP2) Round 7 Implementation Assistance Program Webinar

Transcription

1 Second Strategic Highway Research Program (SHRP2) Round 7 Implementation Assistance Program Webinar Structures Solutions (, R06G, R19A, R19B) March 9, 2016

2 Agenda SHRP2 update Implementation Assistance Program opportunities Product description & assistance opportunities: Nondestructive Testing for Concrete Bridge Decks () Nondestructive Testing for Tunnel Linings (R06G) Service Life Design for Bridges (R19A) Service Limit State Design for Bridges (R19B) Round 7 Schedule Questions 2 2

3 SHRP2 at a Glance SHRP2 Solutions 63 products Solution Development processes, software, testing procedures, and specifications Field Testing refined in the field Implementation 350 transportation projects; adopt as standard practice SHRP2 Education Connection connecting next-generation professionals with next-generation innovations 350 SHRP2 projects nationwide 3 3

4 Focus Areas Safety: fostering safer driving through analysis of driver, roadway, and vehicle factors in crashes, near crashes, and ordinary driving Reliability: reducing congestion and creating more predictable travel times through better operations Capacity: planning and designing a highway system that offers minimum disruption and meets the environmental and economic needs of the community Renewal: rapid maintenance and repair of the deteriorating infrastructure using already-available resources, innovations, and technologies 4 4

5 SHRP2 Implementation: Moving Us Forward 5 5

6 SHRP2 Implementation: Moving Us Forward 6 6

7 SHRP2 Implementation Assistance Program Designed to help State DOTs, MPOs, local agencies, and other interested organizations deploy SHRP2 Solutions. 7 7

8 SHRP2 Structures Products Improving the service life of bridges and tunnels. 8 8

9 Nondestructive Testing (NDT) for Concrete Bridge Decks () On-line repository for bridge, tunnel and pavement NDT technologies 9 9

10 NDT for Tunnel Linings (R06G) Lining assessment with mobile/hand-held technologies

11 Service Life Design for Bridges (R19A) Design Guide for Bridges for Service Life 11 11

12 Service Limit State Design for Bridges (R19B) Longer Lasting, Durable Designs 12 12

13 Nondestructive Testing for Concrete Bridge Decks () Yajai Tinkey Vice President and Associate Engineer Olson Engineering

14 Nondestructive Testing for Concrete Bridge Decks 3/9/

15 Problems 15 15

16 Bridge Deterioration 16 16

17 Challenge: State of Practice 17 17

18 Challenge: Evaluating the Full Range of Deterioration Types Deterioration of Interest Delamination Corrosion Vertical cracking Degradation 18 18

19 Solution Performance evaluation of applicable NDT technologies. Electronic repository of NDT technologies for bridge practitioners

20 NDT Technology Performance Solution Deterioration of Interest Delamination Corrosion Vertical cracking Concrete degradation Performance Evaluation Accuracy Repeatability Speed Ease of use Cost 20 20

21 Example Deliverable from NDT Bottom delamination Sound Deeper than 2.5 delamination (top) Top Delamination Areas with Probable Top Delaminations = 14% Areas with Probable Incipient (Deeper)Top Delaminations = 13% Areas with Probable Bottom Delaminations (or Thin Section) = 5.7% 21 21

22 Benefits 1. Provide more detailed and accurate information about internal deterioration or defects. 2. Enable more objective condition assessments on both project and network levels. 3. Can reduce the frequency of inspections, thus reducing traffic interruptions. 4. Can collect data at rates similar to or faster than traditional methods (chain-dragging and hammer sounding). 5. Provide similar cost between NDT technologies and traditional testing methods. 6. Provide a better bridge management program

23 Round 4 8 IAP States NDT for Bridge Decks 23 23

24 Classroom Training and Field Demo 24 24

25 State Directions State DOT Technologies Interested Direction Status Indiana GPR/IR Hire Consultants Completed the selection process. AEComm and Resource International, Inc. won the on call project. Issued the P.O to Resource International and ready to start the field test anytime now. Virginia GPR Hire Consultants Developing the RFP. Louisiana GPR Hire Consultants Developing the RFP. Oregon GPR/IE/IR Hire Consultants Developing the RFP. Iowa IE Purchase Equipment Developing the specifications. Pennsylvania GPR/IR Purchased 2 cellphone IR camera (Seek Thermal and Flir). Evaluating both cameras. Planning to deploy 2 units for each of 11 districts. Looking for quotes for a Purchase Equipment GPR system. Florida IR Purchased IR cameras (Flir). Completed the training for Purchase Equipment the personnel. Ready for the field test. Missouri Resistivity In house resources Developing field program 25 25

26 Resources Implementation Assistance: Report: Tool: Contacts: Matt DeMarco, FHWA SHRP2 Renewal Program, Patricia Bush, AASHTO Program Manager for Engineering, 26 26

27 Nondestructive Testing for Tunnel Linings (R06G) Dennis Sack Senior Vice President and Principal Engineer Olson Engineering

28 Mapping Defects In or Behind Tunnel Linings (R06G) Use proven high-speed and detailed NDT methods to evaluate tunnel condition as part of an integrated Asset Management program

29 Tunnels in the United States According to the Federal Highway Administration: 473+ highway tunnels in the national inventory (state and federal, including Puerto Rico) spread out across the nation. 37 States have at least 1 tunnel on a highway: California 64 NPS 64 Colorado 38 Photos courtesy of Wikipedia 29 29

30 Tunnel Evaluation New Tunnel Inspection Requirements are now in place for all DOT tunnels across the country with the National Tunnel Inspection Standard (NTIS). Clear inspection and reporting requirements, with new needs for high-speed inspection

31 High-Speed Mapping of Defects In or Behind Tunnel Linings (R06G) Challenge Safely performing tunnel inspections in a high-traffic and confined work space. Solution Use proven NDT scanning technologies to evaluate tunnel linings more quickly and comprehensively. Results then directly coupled with an integrated asset management program

32 Tunnel Deterioration Overview Tunnel deterioration is a major maintenance problem for highway departments. Issues for Tunnel Liners: Corrosion of reinforcing steel Moisture intrusion Debonding/delamination of shotcrete and tile Drainage system failure Cracking of concrete Deformations and bulges 32 32

33 Current SHRP2 Implementation: Pennsylvania and Colorado DOT Penetradar GPR of PennDOT Tunnel Distribution of Cracks Greater Than 1/8, Armstrong Tunnel Initial training on NDT methods completed. Field testing of two PennDOT tunnels completed using various scanning methods. Testing reports due shortly for review. Tunnel-specific asset management programs created and available for sharing with other states

34 R06G Product Approach Participate in educational programs on the use of highspeed NDT methods for evaluation of tunnels. Learn about and apply effective asset management programs that uses NDT data and other sources as inputs. Use these NDT technologies to conduct high-speed evaluations of tunnels. Use the NDT results and other data to populate and use an effective tunnel asset management program

35 Previously Evaluated and Proven NDT Technologies Techniques Used: Air-coupled ground-penetrating radar (GPR) Thermography (handheld or vehicle mounted thermal camera) LiDAR scanning Photogrammetry Ground-coupled GPR Ultrasonic echo Ultrasonic surface waves and impact echo

36 Benefits of NDT Technologies Shorter and possibly fewer tunnel shutdowns during inspections, resulting in fewer detours. Safer for inspectors. Scanning tests provide 100% coverage. LiDAR and Photogrammetry Air Coupled GPR Scanning Infrared Handheld devices to test areas in depth

37 LiDAR and Infrared Scanning Examples 37 37

38 Air Coupled GPR Example Lining Surface ~14 Concrete ~1 Drainage Layer ~14 Shotcrete 38 38

39 Hand-Held IR Example Shotcrete Lined Tunnel IR Image of Debonded Shotcrete (debonds in red) FLIR 1 IR Camera 39 39

40 Service Life Design for Bridges (R19A) Mike Bartholomew Technology Director, North American Bridges CH2M

41 Project Background TRB Research Project, R19A Bridges for Service Life Beyond 100 Years: Service Life Design for Bridges Completed in : FHWA/AASHTO Implementation phase of Service Life Design for Bridges 41 41

42 Service Life Design for Bridges Design structures for service life and durability Go beyond requirements in structural codes: Assess the durability objective Assess the environment and exposure Provide materials and structural detailing that will make the structure last

43 Service Life Design Basics Based on designing for material deterioration over time Corrosion of steel from chlorides (sea water and de-icing agents) Corrosion of reinforcing steel from carbonation (function of humidity, wetting and drying cycles)

44 Service Life Design Basics Based on designing for material deterioration over time Concrete damage from freeze-thaw Concrete damage from alkali aggregate reaction Abrasion of bridge decks from studded tires and chains Breakdown of protective coating systems

45 Service Life Design Strategies Avoidance of deterioration. Use of highly resistant materials, like stainless steel. Design based on deterioration from the environment. Establish exposure conditions and material resistances. Deemed to satisfy ( rules of thumb ). Uses mathematical deterioration models. Full probabilistic (reliability based, statistical analysis of model variables). Semi-probabilistic or deterministic (direct equation solutions with load and resistance factors)

46 Service Life Design for Bridges fib Bulletin 34 Model Code for Service Life Design Written and distributed by the International Federation of Structural Concrete (fib) A reliability-based service life design methodology for concrete structure Similar to Load-Resistance Factor Design ISO 16204:2012 Service Life Design of Concrete Structures 46 46

47 Project Overview Implementation phase of Service Life Design with 4 states and 1 federal agency: Iowa Oregon Virginia Pennsylvania Central Federal Lands Each agency will at least: Complete the service life design for at least one structure. Gather data that will feed into the service life analysis. Example: test concrete mixes, test structures, evaluate current design standard for service life, evaluate RFP wording. Evaluate life-cycle costs

48 Resources

49 Resources Service life design example report for a major structure. Calculation tools for full probabilistic approach to service life design. Excel spreadsheets Graphical solutions Guidance on concrete tests to assess state of concrete structures, exposure conditions. Calculation tools to determine chloride diffusion coefficient of concrete based on chloride profiles

50 Product Value to DOTs More scientific and proactive through-life design approach. Designing material durability properties for different levels of environmental exposure allocates $ where needed. Evaluation of alternatives for life-cycle cost selecting best long-term solution. Quantitative Construction monitoring/testing to assure quality structure is achieved Recorded on birth certificate. Better prediction of condition to maintain/repair/replace for future funding allocation. All leading to longer life structures. Small short-term $ investment Large long-term $ savings

51 Questions? Contacts: Matt DeMarco, FHWA SHRP2 Renewal Program, Patricia Bush, AASHTO Program Manager for Engineering, Subject Matter Expert Team: Mike Bartholomew, CH2M, Anne-Marie Langlois, COWI North America, 51 51

52 Service Limit State Design for Bridges (R19B) Wagdy Wassef, Ph.D., P.E. AECOM Naresh Samtani, Ph.D., P.E. President NCS GeoResources

53 Service Limit State Design Originally, only the strength limit state in the AASHTO Load and Resistance Factor Design (LRFD) specifications was statistically calibrated. The consequences of the loads exceeding the resistance are not well defined for service limit states. Service limit states may be exceeded but the acceptable frequency of exceedance is not known. The load and resistance factors for service limit states were selected to produce results similar to those using earlier specifications (no statistical calibration)

54 General Calibration Process Loads and resistance vary. Failure is assumed when loads exceed the resistance. Low probability of failure constitutes acceptable design. For design purposes, assumptions regarding the value of the loads and the resistance are made to produce acceptable probability of failure. Loads Resistance Probability of Failure 54 54

55 Benefits of Using Calibrated Service Limit States Uniform reliability. The ability to revise the design requirements in the future to correspond to the observed performance by uniformly increasing or decreasing the level of reliability across all bridges. The ability perform a route-specific calibration for routes with unique characteristics (e.g., unusually high traffic volumes)

56 Service Limit State Design Products and the Implementation Process Products Data used in the calibration Calibration process Recommended specifications revisions Implementation AASHTO technical committees incorporate sections relevant to the specifications sections they oversee. States implement recommendations they feel important to them even if AASHTO does not implement them. FHWA incorporates in some of their publications

57 Calibration of Service Limit States General calibration process was developed for service limit states and was revised to fit specific requirements for different limit states. The following limit states were calibrated: Fatigue I and Fatigue II limit states for steel components. Fatigue I for compression in concrete and tension in the reinforcement. Tension in prestressed concrete components. Crack control in decks. Service II limit state for yielding of steel and for bolt slip. Foundations settlement

58 Fatigue of Structural Steel Largest Weigh-In-Motion (WIM) data study. Based on current traffic and vehicles. Established a process to study fatigue using WIM data. The ability to develop site-specific/route-specific fatigue load factors. Revisions to fatigue provisions are being considered by the technical committee on steel bridges (T-14) include: New load factors for Fatigue I and Fatigue II limit states. New number of load cycles per truck passage 58 58

59 Fatigue of Compression in Concrete And Tension in Reinforcement New resistance (fatigue threshold) equations were developed resulting in higher fatigue resistance for reinforcement The new equations are being considered by the technical committee on concrete bridges T

60 Tension in Prestressed Concrete (Service III) Issues investigated: Background and history of changes to AASHTO standard specifications and AASHTO LRFD provisions. Effect of changes in methods of estimating P/S losses on the reliability of bridges. Study of reliability levels using different P/S loss methods. New load factor accepted by T-10 in

61 Crack Control by Distribution of Reinforcement in Decks Review of the background of the LRFD provisions. Study of reliability levels using current provisions indicated uniform reliability; however, is it the correct level of reliability? The ability to control the level of reliability

62 Yielding of Structural Steel and Slip of Bolted Connections Background of the load factor for yielding under service load was investigated. Minimal test results in the early 1960s were used to establish this limit state. Possibility of using single lane distribution factor based on WIM data. Guidance was incorporated in AASHTO LRFD in

63 Live Load Deflections Humans do not feel deflections, they feel the accelerations associated with the deflections and vibrations. AASHTO limits on deflections are a fraction of the span length. Some specifications are based on natural frequency to control the acceleration, not the deflection. R19B indicated that AASHTO s limit generally follow the same trend as controlling accelerations. Guidance added to AASHTO LRFD in static deflection, mm Deflection Limitations for Highway Bridge Superstructure Vibration Existing Spread Box Girders Existing Adjacent Box Girders Existing I Girders Existing Steel Girders ACCEPTABLE without sidewalks with sidewalk, occasional pedestrian use with sidewalks, frequent pedestrian use first flexural frequency, Hz UNACCEPTABLE 63 63

64 Idealized Vertical Deformation Patterns for Bridges : Settlement at a foundation location : Difference in settlement between two adjacent foundations Deformation induces force effects within superstructure AASHTO LRFD incorporates induced force effects due to support deformations through load factor SE 64 64

65 When is a Bridge Structure Affected? CONSTRUCTION POINT CONCEPT Load Z Y X W During construction S Factored Load (Strength Limit) Long term settlement (if applicable) Service Load (Service Limit) F W X Y Z Vertical Displacement Foundation could be shallow (spread footings) or deep (piles, shafts, etc.) 65 65

66 Calibration Process for Load Factor SE What is the uncertainty in estimated values of foundation deformation,? Need to express SE in terms of probability of exceedance (or reliability index) 66 66

67 Example Data from FHWA (1987) for Immediate Settlement of Spread Footings 67 67

68 Section 3, Proposed New Table for SE Immediate settlement Hough method Schmertmann method Local method Deformation SE * Consolidation settlement 1.00 Lateral deformation P-y or SWM soil-structure interaction method 1.00 Local method * *To be determined by the owner based on local geologic conditions

69 Flow Chart Accompanying guided step-by-step process for implementation -0 CONCEPT 69 69

70 Implementation Tools White paper Several examples Flow chart Proposed LRFD specification revisions and commentaries Under consideration by T-15 and T-5 committees SHRP2 Round 7 Implementation Assistance Program (IAP) Material available at:

71 Benefits of Using Calibrated Foundation Deformations Consideration of calibrated foundation deformations in the bridge design process can lead to use of cost-effective structures with more efficient foundation systems. Permit enhanced use of cost-effective spread footings and true bridge abutments (spread footing on top of MSE wall). The proposed approach and modifications will help avoid overly conservative criteria that can lead to: a) foundations that are larger than needed, or b) a choice of less economical foundation type (such as, using a deep foundation at a location where a shallow foundation would be adequate)

72 Assistance Opportunities Round 7 IAP April 1 st to 29 th Nondestructive Testing for Concrete Bridge Decks () Nondestructive Testing for Tunnel Linings (R06G) Service Life Design for Bridges (R19A) Service Limit State Design for Bridges (R19B) Lead Adopter Incentive 5 available Up to $100,000 each User Incentive 8 available Up to $30,000 each 8 available Up to $30,000 each Technical assistance Who can apply: State DOTs, MPOs, local and tribal agencies. Local agencies must coordinate application submittals with their state DOTs

73 Structures Product Information Simply Google SHRP2 for the FHWA and AASHTO SHRP2 product websites

74 Timeline Product-specific webinars March 8 March 22, 2016 Round 7 Application Period April 1 April 29, 2016 Round 7 Recipients Announced June

75 For More Information Product Leads: Matt DeMarco FHWA Product Lead Patricia Bush AASHTO Product Lead Additional Resources: GoSHRP2 Website: AASHTO SHRP2 Website: GoSHRP2 Alert Sign Up: fhwa.dot.gov/goshrp2 fhwa.dot.gov/goshrp2/contact Download now: Copy of this presentation Product webinar schedule and registration information Links to Round 7 product research recordings (SHRP2 Tuesdays) Round 7 assistance opportunities 75 75