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
AGENDA KNOWLEDGE BASE INVOLVEMENT TO DATE INTERIM ASSESSMENT STRUCTURAL TESTING
KNOWLEDGE BASE
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
ASR IN THE STATE OF TEXAS Lawrence et al., 1999 DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 5
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
FERGUSON STRUCTURAL ENGINEERING LABORATORY DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION KNOWLEDGE BASE 7
INVOLVEMENT TO DATE
INVOLVEMENT TO DATE Paper on ASR Paper on ACI 318-71 Start Walkdown at Seabrook Station NRC Management Meeting Nov Dec Jan Feb Mar Apr 2011 2012 Reviewed Interim Structural Assessment DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION INVOLVEMENT TO DATE 9
INTERIM STRUCTURAL ASSESSMENT Expert Review DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION INVOLVEMENT TO DATE 10
INTERIM ASSESSMENT
INTERIM ASSESSMENT One-Way Shear Strength Strength Margin ASR OR ACI 318-71 Anchorage of Reinforcement Original Condition Current Condition DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION 12
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., 1998 5 47 Reinforcement Anchorage without Transverse Reinforcement Chana, 1989 12 12 No. 5 DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION 13
STRUCTURAL TESTING
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
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
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
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
SHEAR TESTING Load Cells Load Cells C L Test Region Displacement Transducers DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 19
SHEAR TESTING 3 6 Reinforcement Mats Applied Load TBD 2 Test Region Support Reaction Support Reaction 3-2 21-4 3-2 DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 20
ANCHORAGE TESTING Load Cells Load Cells Test Region Displacement Transducers DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 21
ANCHORAGE TESTING 3 6 TBD Reinforcement Mats Applied Loads TBD Transverse Reinforcement Test Region 2 Support Reaction Lap Splice Support Reaction 3-2 21-4 3-2 DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 22
PROJECT WORKFLOW Beam Fabrication Conditioning & Monitoring Structural Testing DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 23
CONCRETE MIXTURE Maine Granite Sodium Hydroxide Lehigh Cement Jobe Sand FSEL DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 24
BEAM FABRICATION DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 25
CONDITIONING DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 26
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
STRUCTURAL TESTING DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 28
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
REPRESENTATIVE RESULTS 12 pan Shear, V/bd f' c Normalized Test S 10 8 6 4 2 0 0 0.2 0.4 0.6 0.8 1 1.2 Deflection at Load [in] DR. OGUZHAN BAYRAK, PE STRUCTURAL ASSESSMENT OF SEABROOK STATION STRUCTURAL TESTING 30
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
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
QUESTIONS