STRUCTURAL ASSESSMENT OF SEABROOK STATION

Transcription

1 STRUCTURAL ASSESSMENT OF SEABROOK STATION Findings and Structural Testing Plan OGUZHAN BAYRAK, Ph.D., P.E. Ferguson Structural Engineering Laboratory The University of Texas at Austin April 23, 2012

2 AGENDA KNOWLEDGE BASE INVOLVEMENT TO DATE INTERIM ASSESSMENT STRUCTURAL TESTING

3 KNOWLEDGE BASE

4 OGUZHAN BAYRAK, Ph.D., P.E. Investigations into the effects of ASR in highway structures were initiated in 2005 Effects of ASR on multiple aspects of structural behavior have been evaluated through large-scale laboratory testing Critical insights gained from laboratory testing results and international literature DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 4

5 ASR IN THE STATE OF TEXAS Lawrence et al., 1999 DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 5

6 LARGE-SCALE EXPERIMENTAL RESEARCH TxDOT IAC 128XXIA006 Flexure and Shear Behavior TxDOT IAC 5DDIA004 Anchor Bolt Behavior DR. OGUZHAN BAYRAK, PE TxDOT IAC 128XXIA007 Dapped End Behavior STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 6

7 FERGUSON STRUCTURAL ENGINEERING LABORATORY DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 7

8 INVOLVEMENT TO DATE

9 INVOLVEMENT TO DATE Paper on ASR Paper on ACI Start Walkdown at Seabrook Station NRC Management Meeting Nov Dec Jan Feb Mar Apr Reviewed Interim Structural Assessment DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION INVOLVEMENT TO DATE 9

10 INTERIM STRUCTURAL ASSESSMENT Expert Review DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION INVOLVEMENT TO DATE 10

11 INTERIM ASSESSMENT

12 INTERIM ASSESSMENT One-Way Shear Strength Strength Margin ASR OR ACI Anchorage of Reinforcement Original Condition Current Condition DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION 12

13 INTERIM ASSESSMENT Performance of large ASR-affected structures is not well represented by current test data set. Limit State Lower-Bound Reference Specimen Scale One-Way Shear without Transverse Reinforcement Ahmed et al., Reinforcement Anchorage without Transverse Reinforcement Chana, No. 5 DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION 13

14 STRUCTURAL TESTING

15 METHODOLOGY Interim Structural Assessment Today Shear and Lap Splice Test Programs Quantify Margin Available Above Code-Calculated Capacities Quantify Impact of ASR on Structural Capacity and Stiffness Final Structural Assessment Aging Management Program DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 15

16 TEST PROGRAMS SHEAR 9 Beams LAP SPLICE 9 Beams Design Margin Effects of ASR Retrofit Strategies Control Series I Series II C-1 I-1 I-2 I-3 I-4 II-1 II-2 II-3 II-4 DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 16

17 REPLICATION OF SEABROOK DETAILS The reinforcement detailing will: represent the lack of through-thickness reinforcement within tunnel walls enable focused study of shear and anchorage behavior at current and future levels of ASR degradation DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 17

18 REPLICATION OF SEABROOK DETAILS The concrete mixture will: be developed through trial batching with representative coarse and fine aggregates be sufficiently reactive to obtain the necessary data in a timely manner develop mechanical properties that are representative of Seabrook structures DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 18

19 SHEAR TESTING Load Cells Load Cells C L Test Region Displacement Transducers DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 19

20 SHEAR TESTING 3 6 Reinforcement Mats Applied Load TBD 2 Test Region Support Reaction Support Reaction DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 20

21 ANCHORAGE TESTING Load Cells Load Cells Test Region Displacement Transducers DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 21

22 ANCHORAGE TESTING 3 6 TBD Reinforcement Mats Applied Loads TBD Transverse Reinforcement Test Region 2 Support Reaction Lap Splice Support Reaction DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 22

23 PROJECT WORKFLOW Beam Fabrication Conditioning & Monitoring Structural Testing DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 23

24 CONCRETE MIXTURE Maine Granite Sodium Hydroxide Lehigh Cement Jobe Sand FSEL DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 24

25 BEAM FABRICATION DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 25

26 CONDITIONING DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 26

27 EXPANSION MONITORING Cracking indices will be correlated to measured expansions as well as structural test results for use in Seabrook Station. Cracking Indices Expansions DR. OGUZHAN BAYRAK, PE Structural Performance STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 27

28 STRUCTURAL TESTING DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 28

29 ANALYSIS OF RESULTS P = k Δ BEAM Damaged Force, P Applied k ASR Undamaged Strength & Stiffness Implications of ASR k CONTROL Beam Deformation, Δ BEAM DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 29

30 REPRESENTATIVE RESULTS 12 pan Shear, V/bd f' c Normalized Test S Deflection at Load [in] DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 30

31 APPLICATION OF RESULTS Original Design Margin % Reduction Effect of ASR Proven Retrofit Strategy Shear Anchorage Stiffness Crack Index Final Structural Assessment Aging Management Program Structural Monitoring Program Predefined Action Levels

32 SCHEDULE Interim Structural Assessment Today Shear and Lap Splice Test Programs Quantify Margin Available Above Code-Calculated Capacities Quantify Impact of of current ASR on ASR on Structural Capacity and Stiffness Final Structural Assessment Aging Management Program Final Report APRIL 2014 Note: Ambient conditions may impact development of ASR in test specimens and project schedule DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 32

33 QUESTIONS