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  • United States Society on Dams

    Changing Times The Challenges andRisks of Managing Aging Infrastructure

    Under a New Financial Reality

    33rd Annual USSD Conference

    Phoenix, Arizona, February 11-15, 2013

  • CONTENTS

    Plenary Session

    USACE Experience in Performing Constructability Reviews . . . . . . . . . . . . . . . 1

    David Paul, Mike Zoccola and Vanessa Bateman, Corps of Engineers; and Dan

    Hertel, Engineering Solutions, LLC

    Levees

    Levee Evaluation with Ground-Penetrating Radar . . . . . . . . . . . . . . . . . . . . 3

    Hussein Khalefa Chlaib, Haydar Al-Shukri, Hanan Mahdi, M. Mert Su,

    Aycan Catakli and Najah Abd, University of Arkansas at Little Rock

    How Enhanced and Economically Viable Engineering Analysis Can Help Levee

    Owners Evaluate Their Inventory in Response to FEMAs Proposed Approach for

    Non-Accredited Levees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

    Todd Mitchell, Paul Grosskruger and Cornelia Dean, Fugro Constultants, Inc.;

    and Bob Woldringh, Furgro Engineers, BV

    Use of Fragility Curves in Assigning Levee Remediation Priorities . . . . . . . . . . . 7

    Rich Millet, Sujan Punyamurthula, Derek Morley and Loren Murray, URS

    Corporation

    Probabilistic Evaluation of Levee Distress for the Sacramento River Bank

    Protection Project . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

    Khaled Chowdhury, URS Corporation; Derek Morley and Mary Perlea, Corps

    of Engineers; Wilbur Huang, California Department of Water Resources; and

    Matthew Weil and Saritha Aella, URS Corporation

    Integrating Levee Performance Assessments into Complex Flood Protection

    Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

    T. Mitchell, Fugro Consultants, USA; R. Kluskens, Royal HaskoningDHV;

    B. Woldringh, Fugro Consultants BV; M.T. van der Meer, Fugro WaterServices;

    R.G. Kamp and C. de Gooijer, HKV Consultants; M.M. Hillen, Royal

    HaskoningDHV

    Concrete Dams

    Updated Stress and Stability Analysis of a TVA Dam . . . . . . . . . . . . . . . . . . 13

    Dan D. Curtis, HATCH Ltd.; Husein Hasan, Tennessee Valley Authority; Frank

    Feng and Bob He, HATCH Ltd.; and Justin Long, Tennessee Valley Authority

    v

  • An Advanced Model for Simulation of ASR Behavior at Roanoke Rapids Dam . . . . . 15

    Brian R. Reinicker and Farzad Abedzadeh, HDR Engineering, Inc.; Robin G.

    Charlwood, Robin Charlwood & Associates; and John A. Cima, Dominion

    Resources Services, Inc.

    Investigations to Evaluate Performance of Concrete Arch Dam Affected by

    Alkali-Silica Reaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

    Daniel D. Mares, Bureau of Reclamation

    Structural Analysis of Corbels on an Aging Multiple-Arch Dam . . . . . . . . . . . . 19

    Brad B. Watson, Victor M. Vasquez and Les Boyd, Freese and Nichols, Inc.;

    Doug Witkowski, Lower Colorado River Authority; and James O. Jirsa,

    University of Texas at Austin

    Integrating Infrastructure Upgrades with Gravity Dam Repairs . . . . . . . . . . . . 21

    Timothy W. Johnston, Gannett Fleming, Inc.; John A. Wilkes, Carpi USA Inc.;

    Mishelle Noble-Blair, Fairfax Water; and Thomas B. Pursel, Gannett Fleming,

    Inc.

    Explicit Seismic Analysis of Mossyrock Dam . . . . . . . . . . . . . . . . . . . . . . 23

    Dan D. Curtis, Hatch Associates Consultants; Gurinderbir Sooch, HATCH Ltd.;

    and Toby Brewer and Andrew Schildmeyer, Tacoma Power

    Strength Monitoring for RCC Dam During Construction . . . . . . . . . . . . . . . . 25

    James Stiady, Kleinfelder; Frank Collins, Parsons; and Jim Zhou, Gerald E.

    Reed III, Wade Griffis and Jeffrey A. Shoaf, San Diego County Water Authority

    Practical Application of RFC Dam Construction Based on Cheap Mix Design

    of SCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

    Qiong Wu, Xuehui An, Miansong Huang and Feng Jin, Tsinghua University

    Filling an Expanded Reservoir A Myriad of Considerations . . . . . . . . . . . . . 29

    Kelly L. Rodgers, Gerard E. Reed III and Jim Zhou, San Diego County Water

    Authority; Surraya Rashid and Rosalva Morales, City of San Diego; and

    Thomas O. Keller, GEI Consultants, Inc.; and Anna E. Kolakowski, California

    Department of Water Resources

    Tailings Dams

    Dam Break Analysis Applied to Tailings Dams: USSD Workshop Summary and

    Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

    Jos L.M. Clemente, Bechtel Power Corporation; Robert E. Snow, DAppolonia

    Engineering; Carmen Bernedo, MWH Global, Inc.; Clinton Strachan, MWH

    Americas, Inc.; and Andy Fourie, University of Western Australia

    vi

  • Design, Construction, and Performance of a Seepage Cutoff Barrier in a Dam . . . . 33

    Ivn A. Contreras, Jon D. Ausdemore, Joe A. Welna and Rachel E. Franz, Barr

    Engineering Co.

    Seismic Design of Perimeter Slurry Walls for the Kingston Coal Ash Pond Closure . . 35

    Alan F. Rauch, Stantec, Inc.; Rodney P. McAffee, C-CORE; and Yong Wu and

    Luis J. Arduz, Stantec, Inc.

    Foundations

    Performance of Prewetted Loess Foundations for Embankment Dams . . . . . . . . . 37

    William Engemoen, Bureau of Reclamation

    Erodabilty of Seepage Barrier Materials . . . . . . . . . . . . . . . . . . . . . . . . 39

    Nathan Braithwaite and John Rice, Utah State University; and David Paul,

    Corps of Engineers

    Blue Lake Dam Left Abutment Stabilization Design . . . . . . . . . . . . . . . . . . . 41

    James H. Rutherford, Peter Friz, John Werner and Lingmin Feng, HATCH

    Renewable Power; and Jerry Higgins, Colorado School of Mines

    Hydraulics and Hydrology

    Performance of RCC Strengthened Levee in Full-Scale Overtopping Tests . . . . . . . 43

    Fashad Amini and Lin Li, Jackson State University

    Scour of Discontinuous Blocky Rock . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

    Michael George and Nicholas Sitar, University of California, Berkeley

    Finite Element Modeling of Trunnion Rods . . . . . . . . . . . . . . . . . . . . . . . 47

    Mark A. Cesare, J. Darrin Holt and Robert F. Lindyberg, FDH Engineering,

    Inc.; and Jim J. Lua and Xiujun Fang, Global Engineering and Materials, Inc.,

    Effects of Bronze and Composite Sleeves on Trunnion Yoke Plate Stress

    Concentrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

    Thomas J. Walker, Black & Veatch Corporation; Kevin Z. Truman, University

    of Missouri-Kansas City; and Kurt A. Jacobs, Corps of Engineers

    Hodenpyl Hydroelectric Plant Spill Tube Headgate Replacement Project . . . . . . 51

    Tor Hansen, Barr Engineering Company; Adam Monroe, Consumers Energy

    Company; and Rusty Friedle, Gerace Construction

    Inundation Mapping for Impending Record Reservoir Releases Missouri River

    Flood of 2011 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

    Thomas Gorman, Lowell Blankers, Laurel Hamilton, Colleen Horihan, Troy

    Ingram, Tony Krause, Curtis Miller, Eric Morrison, Michelle Schultz, Megan

    Splattstoesser and Neil Vohl, Corps of Engineers

    vii

  • Saving Lives with 2-D Inundation Flood Modeling as a Dam Design Tool . . . . . . . 55

    Milan Jankovic and Shane Willard, Bureau of Indian Affairs

    IDF Determination Using Risk Analysis at the Norway-Oakdale Project . . . . . . . . 57

    Eric J. Gross, Federal Energy Regulatory Commission

    Modeling a Low-Head Dam Retrofit with a 2-D Hydraulic Model (Adaptive

    Hydraulics) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

    Jeff Weiss, Jon Ausdemore, Tom MacDonald and Ron Koth, Barr Engineering

    Company

    Approach for Mapping Flooding Risk near Lake Okeechobee, Florida . . . . . . . . . 61

    Guillermo Simn, Taylor Engineering, Inc.; and Ao Yi, AECOM

    Comparison of Modern Day Inundation Modeling Techniques (2-D versus 1-D,

    with 3-D on the Horizon) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

    Milan Jankovic and Shane Willard, Bureau of Indian Affairs

    Dam Safety

    Incorporating Uncertainties in the Estimation of Vulnerabilities for Security Risk

    Assessments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

    J. Darrell Morgeson, Institute for Defense Analyses; Yazmin Seda-Sanabria,

    Corps of Engineers; Enrique E. Matheu, U.S. Department of Homeland Security;

    and Michael J. Keleher, Institute for Defense Analyses

    Semi-Quantitative Risk Categorization for Periodic Dam Safety Assessments . . . . . 67

    Timothy M. OLeary and Gregg A. Scott, Corps of Engineers

    Minimizing Over-Conservatism in Dam Safety Modifications through the Careful

    Use of Risk Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

    Daniel W. Osmun, William R. Fiedler and William O. Engemoen, Bureau of

    Reclamation

    Look Both Ways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

    Kim de Rubertis, Consulting Engineer; and C. van Donkelaar, McMillen, LLC

    Interim Risk Reduction Measures Plans: Lessons Learned . . . . . . . . . . . . . . . 73

    Jacob Davis, Corps of Engineers

    Plan for the Safety of Aging Dams; Plan the Work, Work the Plan . . . . . . . . . . . 75

    William J. Friers, CDM Smith; Neil R. Bonesteel, City of Troy, NY; Kapila S.

    Pathirage, CDM Smith; and Chris E. Wheland, City of Troy, NY

    viii

  • An Innovative Response Plan for Potential Seismic Failure Modes at Priest

    Rapids Dam. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

    James H. Rutherford, HATCH Associates Consultants Inc.; Dave Mishalanie,

    Grant County Public Utility District No. 2; J. Groeneveld and Nikou Snell, Hatch

    Ltd.; and Mohammed Badruzzaman, HATCH Associates Consultants Inc.

    Increasing Prickett Dam Height for New PMF . . . . . . . . . . . . . . . . . . . . . 79

    Michael McCaffrey and Tony Plizga, Parsons Brinckerhoff; Ben Trotter and

    Todd Poehlman, Integrys Business Support; and Lorna Langone, Parsons

    Brinckerhoff

    Lake Delhi Dam Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

    William R. Fiedler, Bureau of Reclamation; Wayne King, Federal Energy

    Regulatory Commission; Neil Schwanz, Corps of Engineers; and William

    Holman, Stanley Consultants, Inc.

    Earthquakes

    Overburden Correction Factors for Predicting Liquefaction Resistance Under

    Embankment Dams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

    Jack Montgomery and Ross W. Boulanger, University of California, Davis; and

    Leslie F. Harder, Jr., HDR Engineering, Inc.

    Fault Rupture Risk Evaluation and Mitigation at the Isabella Auxiliary Dam . . . . . 85

    David C. Serafini and Henri V. Mulder, Corps of Engineers

    Seismic Analysis of the Baker River Hydroelectric Project West Pass Dike . . . . . . 87

    Lin Zhao, Jason E. Hedien and Julie Stanaszek, MWH Americas, Inc.; and

    Zakeyo Ngoma, Puget Sound Energy

    Seismic Stability Evaluation of Anderson Dam, Santa Clara County, California . . . . 89

    Marc J. Ryan, AMEC Environment and Infrastructure; Michael Mooers, Santa

    Clara Valley Water District; Faiz I. Makdisi, AMEC Environment and

    Infrastructure; James Nelson, Santa Clara Valley Water District; and Christopher

    Slack, AMEC Environment and Infrastructure

    Terminal Dam A Small Facility with Big Problems. . . . . . . . . . . . . . . . . . 91

    Tara Schenk McFarland, Bureau of Reclamation

    Impact of Embedded Tower on Seismic Risk of an Embankment Dam . . . . . . . . . 93

    Michael E. Ruthford, Chung F. Wong, Michael Ma and Vlad G. Perlea, Corps

    of Engineers; and Michael H. Beaty, Beaty Engineering LLC

    Development of the Calaveras Dam Replacement Project Challenges and

    Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

    Michael Forrest, Noel Wong and John Roadifer, URS Corporation; and Daniel

    Wade and Gilbert Tang, San Francisco Public Utilities Commission

    ix

  • Development of a Risk-Informed Approach to the Seismic Evaluation of

    Hydropower Projects Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . 97

    Martin W. McCann, Jr., Jack R. Benjamin and Associates, Inc.; David W. Lord,

    Federal Energy Regulatory Commission; Kevin Marshall, Grant County Public

    Utility District; David Mishalanie, Grant County Public Utility District; Gene

    Yow, Chelan County Public Utility District; and Bill Christman, Chelan County

    Public Utility District

    Development of a Risk-Informed Approach to the Seismic Evaluation of

    Hydropower Projects The Owners Perspective . . . . . . . . . . . . . . . . . . . 99

    Bill Christman, Chelan County Public Utility District; Kevin Marshall and David

    Mishalanie, Grant County Public Utility District; Gene Yow, Chelan County

    Public Utility District; David W. Lord, Federal Energy Regulatory Commission;

    and Martin W. McCann, Jr., Jack R. Benjamin and Associates, Inc.

    Development of a Risk-Informed Approach to the Seismic Evaluation of

    Hydropower Projects FERC Perspective . . . . . . . . . . . . . . . . . . . . . . 101

    David W. Lord, Federal Energy Regulatory Commission; Martin W. McCann,

    Jr., Jack R. Benjamin and Associates, Inc.; Kevin Marshall and David

    Mishalanie, Grant County Public Utility District; and Gene Yow and Bill

    Christman, Chelan County Public Utility District

    Environment

    Reservoir Sustainability Workshop, Lakewood, Colorado, July 10-12, 2012 . . . . . 103

    Timothy J. Randle and Kent L. Collins, Bureau of Reclamation

    Sustainable Water Infrastructure in California . . . . . . . . . . . . . . . . . . . . . 105

    Lawrence H. Roth, ARCADIS U.S.

    Resolving Complex Challenges in River Restoration The San Joaquin River

    Restoration Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

    William R. Swanson, Jill C. Chomycia, Jeffrey T. Payne and Heather Shannon,

    MWH Americas, Inc.; Alicia Forsythe, Bureau of Reclamation; and Kevin

    Faulkenberry, California Department of Water Resources

    Decommissioning

    Elwha River Restoration: Sediment Management First Year Results . . . . . . . . . 109

    Timothy J. Randle and Jennifer A. Bountry, Bureau of Reclamation

    Large Scale Dam Removal on the Klamath River Monetizing the Social

    Effects of Large Scale Dam Decomissioning . . . . . . . . . . . . . . . . . . . . . . 111

    Ben Swann and Chris Park, CDM Smith

    x

  • Working Together with Minimum Budget to Breach a High-Hazard Dam . . . . . . . 113

    Stephen L. Whiteside, CDM Smith; Emily Davenport, City of Valdosta, Georgia;

    and Jose Maria Guzman, CDM Smith

    Construction and Rehabilitation

    Pine Creek Dam Phase V Rock Investigation . . . . . . . . . . . . . . . . . . . . 115

    Kathryn A. White, Corps of Engineers

    Reducing Seepage into Inter-Gallery Drains Within the Narrows Dam Intake

    Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

    Stefan Schadinger, Parsons Brinckerhoff; Mark J. Gross, Alcoa Power

    Generating Inc.; and Michael McCaffrey, Paul F. Shiers and Christopher

    Godwin, Parsons Brinckerhoff

    Early Contractor Involvement: Case Studies for Reducing Costs, Compressing

    Schedules, and Improving Projects . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

    Del A. Shannon and John F. Bowen, ASI Constructors, Inc.

    The Bid Process Closing the Communication Gap between Engineer and

    Contractor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

    Mark Landis, Schnabel Engineering; and Page Riley, Philips and Jordan Inc.

    Development and Field Testing of a Pressure Sensing Grout Packer . . . . . . . . . 123

    David Paul, Jeffrey Schaefer and Brook Brosi, Corps of Engineers; Patrick

    Carr, The Judy Company, Inc.; and Chad Conti, GEI Consultants, Inc.

    McClure Penstock Replacement Project From Failure to Reconstruction . . . . . 125

    Whitney Hansen and William J. Forsmark, Barr Engineering Company; and

    Robert J. Meyers, Upper Peninsula Power Company

    Lake Townsend Dam Replacement Challenges in Building a New Dam at the

    Toe of an Old Dam under Full Reservoir Head . . . . . . . . . . . . . . . . . . . . 127

    Robert Cannon, Tillman Marshall, Greg Paxson and Frederic Snider, Schnabel

    Engineering; and Melinda King, City of Greensboro

    Seismic Remediation Design and Construction of Key-Block: Mormon Island

    Auxiliary Dam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

    M. Jonathan Harris and Michael J. Romansky, Bureau of Reclamation

    Geotechnical Concerns in Addressing Seepage at a Rock-Filled, Wood-Faced

    Dam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

    John C. Stoessel, Southern California Edison; John Wilkes, CARPI USA, Inc.;

    and Craig McElfresh, MCS Construction, Inc.

    xi

  • Concrete Placement and Rehabilitation at the Hannawa Development . . . . . . . . 133

    Bryce Mochrie, Parsons Brinckerhoff; Lee Talbot, Brookfield Renewable Energy

    Group; and Kevin Finn, Parsons Brinckerhoff

    Developing Great Hydroelectric Projects in a Challenging Social and Economical

    Environment: La Romaine Complex, Situated in Northern Quebec, Canada . . . . . 135

    Vlad Alicescu, Jean-Pierre Tournier and Pierre Vannobel, Hydro-Quebec

    Reduce Risk of Cofferdam Failure with RCC A Historical Perspective . . . . . . . 137

    Daniel L. Johnson, Tetra Tech, Inc.; and Kenneth D. Hansen, Consulting

    Engineer

    Rock Anchors for Dams: A Five-Year Update . . . . . . . . . . . . . . . . . . . . . 139

    Donald A. Bruce, Geosystems, L.P.; John S. Wolfhope, Freese and Nichols, Inc.;

    and Jesse D. Wullenwaber, Schnabel Engineering, LLC

    Rehabilitation of Temporary Composite Dams Case Study: Mared Soil-Sheet

    Pile Dam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

    Saber Alidadi and Masoud Hakami, Khuzestan Water & Power Authority

    Monitoring and Instrumentation

    ROV Sonar Inspection of a Power Tunnel . . . . . . . . . . . . . . . . . . . . . . . 143

    Florijon Dhimitri, Parsons Brinckerhoff; Richard Glenn, Glenn Underwater

    Services, Inc.; Michael Sabad, APGI; and Olga Zabawa, Parsons Brinckerhoff

    Libby Dam Hemispherical Bulkhead Inspection, A 30-Story Descent to a Dam

    Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

    Kenwarjit S. Dosanjh, Travis L. Ford and Samuel M. Planck, HDR

    Engineering, Inc.; and Joshua J. Erickson and Michael T. Likavec, Corps of

    Engineers; and Greg Mayer, Ropeworks/Mistras Group, Inc.

    Performance Evaluation of Upstream Slope Protection During Reservoir

    Drawdown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

    Donald J. Montgomery, Christine T. Weber and Terrence E. Arnold, MWH

    Americas, Inc.

    Early Warning System at Creekside Dams Putting it to the Test . . . . . . . . . . 149

    Laura LaRiviere, Kleinfelder, Inc.; and Brian Boswell, Umpqua Indian Utility

    Cooperative

    Dam Safety Training for Dam Operating Personnel . . . . . . . . . . . . . . . . . . 151

    Jay N. Stateler, Bureau of Reclamation

    Efficiency and Automation: Are Automated Data Acquisition Systems More

    Efficient than Manual Methods? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

    Christopher J. Hill, Metropolitan Water District of Southern California

    xii

  • Subsidence

    Investigative Procedure for Assessing Earth Fissure Risk for Dams and Levees . . . 155

    Kenneth Fergason and Michael Rucker, AMEC Environment and Infrastructure,

    Inc.; and Michael Greenslade, Flood Control District of Maricopa County

    InSAR as a Subsidence Characterization Tool for Flood Control Dam Studies . . . . 157

    Bibhuti B. Panda, Michael L. Rucker and Kenneth C. Fergason AMEC

    Environment and Infrastructure, Inc.; Michael D. Greenslade, Flood Control

    District of Maricopa County

    Characterization of Subsidence Impacting Flood Control Dams and Levees . . . . . 159

    Michael Rucker and Kenneth Fergason, AMEC Environment and Infrastructure,

    Inc.; Michael Greenslade, Flood Control District of Maricopa County; and

    Lawrence Hansen, AMEC Environment and Infrastructure, Inc.

    Laboratory Testing of Critical Hydraulic Conditions for the Initiation of Piping . . . 161

    Mandie Swainston-Fleshman and John Rice, Utah State University

    Ashton Dam

    Can FERCs Risk Informed Decision Making (RIDM) Save You Money? Yes!

    A Case Study of Ashton Dam, Idaho . . . . . . . . . . . . . . . . . . . . . . . . . . 163

    Frank L. Blackett, Justin F. Smith and Patrick J. Regan, Federal Energy

    Regulatory Commission

    Embankment Dams

    Potential for Cracking around Outlet Conduits and its Impact on Seepage

    Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

    Keith A. Ferguson, Mahdi Soudkhah and Elena Sossenkina, HDR Engineering,

    Inc.

    Economical and Reliable Solutions for Arresting Surficial Slope Failures in

    Earthen Dams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

    Jos Hernndez, Corps of Engineers; Bhaskar C. S. Chittoori and Minh Le,

    University of Texas at Arlington; Les Perrin, Corps of Engineers (retired); and

    Ken McCleskey, Corps of Engineers; and Anand J. Puppala, University of Texas

    at Arlington

    Field Testing of Crushed Ignimbrite for Dam Filter Material . . . . . . . . . . . . . 169

    Lelio H. Mejia, URS Corporation

    Evaluation of the Central Filter at Saddleback Flood Retarding Structure . . . . . . 171

    Dean B. Durkee, Gannett Fleming, Inc.; Sam Sherman, Flood Control District of

    Maricopa County; and Frances Ackerman, Gannett Fleming, Inc.

    xiii

  • Devils Lake Flood Risk Management Geotechnical Aspects . . . . . . . . . . . . 173

    Paul D. Madison, Corps of Engineers; and Stephen L. McCaskie, Hanson

    Professional Services

    Effect of Anisotropic Permeability on Phreatic Line Recession in Homogeneous

    Earth Dams Under Reservoir Rapid Draw Down . . . . . . . . . . . . . . . . . . . 175

    V. Rashidian, Imam Khomeini International University

    xiv

  • 1

    USACE EXPERIENCE IN PERFORMING CONSTRUCTABILITY REVIEWS

    David Paul1 Mike Zoccola2

    Vanessa Bateman3 Dan Hertel4

    ABSTRACT

    The Army Corps of Engineers (USACE) is implementing risk informed decision processes for the dam and levee safety programs. These processes prioritizes projects that have actionable failure modes with significant consequences, so that risks to society are being reduced with reduced budgets available to federal agencies that significant infrastructure responsibilities. The Total Design and Construction Process stresses that design and construction teams are integrated throughout the design and construction phases. Developing a systematic approach, with experienced people representing the design and construction disciplines can identify potential issues and mitigate them before they manifest themselves during the construction phase. Wolf Creek Dam (USACE Nashville District) is classified a DSAC 1 (most serious classification) and is undergoing modifications to construct a cutoff wall to mitigate seepage and piping failure modes. The authors describe three scenarios of conducting constructability reviews to identify potential risks presented during construction and further develop project designs and approaches to minimize and appropriately allocate these risks. Three scenarios are described: 1.) Performing a constructability review of proposed engineering alternatives to address actionable failure modes for Isabella Dam2.) Performing a constructability review of potential high risk construction activities in Critical Area 1 (in karst foundation geology) for Wolf Creek Dam which identified possible failure modes and utilized event trees to estimate the risk; 3.) Performing a qualitative risk analyses of potential failure modes for Wolf Creek Dam which could affect the operation of the Switchyard/Powerhouse. These examples will demonstrate the value of various approaches to constructability reviews that were successful in reducing overall project costs and identified risks to both the owner and contractor. The project team must meld the appropriate approach to the current phase of the project. Constructability reviews during the feasibility stage would likely not be appropriate for the final design or construction phase. Properly conducted constructability reviews can significantly alter the course of the project and result in cost and time savings, as well as reduced risk. 1 Lead Civil Engineer, USACE Risk Management Center, 12300 W. Dakota Ave Suite 230, Lakewood, CO 80228, Phone 720-289-9042, [email protected] 2 Chief of Engineering, USACE Nashville District, 801 Broadway, Nashville, TN 37203, [email protected] 3 Engineering Geologist, USACE Nashville District, 801 Broadway, Nashville, TN 37203, [email protected] 4 President, Engineering Solutions, LLC, 11983, Bozeman, MT 59719, [email protected]

  • NOTES

    2

  • 3

    LEVEE EVALUATION WITH GROUND-PENETRATING RADAR Hussein Khalefa Chlaib5 Haydar Al-Shukri6 Hanan Mahdi7 M. Mert Su8 Aycan Catakli9 Najah Abd10

    ABSTRACT The Big Dam Bridge (BDB) levee on the Arkansas River at Little Rock, AR, and the Lollie Levee near Conway, AR, were surveyed with Ground Penetrating Radar (GPR) to assess their structural integrity. GSSI SIR-30 and SIR-3000 systems with multi-frequency (200, 400, and 900MHz) antennas were utilized. The purpose of this study was to detect cavities, continuous animal burrows, and any deformation in the levee body. GPR profiles exhibited many sub-surface anomalies at various depths. Several holes were dug to inspect the true nature of the shallower anomalies to ground-truth the reliability of the GPR data. Steven Soil Sensor was utilized to measure the dielectric constant near the surface of the levees. These values were used to calculate the precise depth of the anomalies that were detected by GPR. Connected empty cavities, continuous animal burrows, clay clasts, and metal objects were found at different depths having different sizes. The depths of the located features ranged between 0.12m and 0.30m and their diameters ranged from 0.06m to 0.08m. Similar to the shallow anomalies, deeper anomalies with normal and reversed polarities were present throughout the GPR profiles which indicate that similar features exist at depth.

    5 PhD Candidate, Applied Science Dep. University of Arkansas at Little Rock, 2801 South University, ETAS 555, Little Rock, AR 72204-1099, (501)569-8349, [email protected] 6 Professor and Chair, Applied Science Dep. University of Arkansas at Little Rock, 2801 South University, ETAS 300O, Little Rock, AR 72204-1099, (501)569-8000, [email protected] 7 Research Associate Professor, Graduate Institute of Technology (GIT), University of Arkansas at Little Rock, 2801 South University, ETAS 101C, Little Rock, AR 72204-1099, (501)569-8305 [email protected] 8 Research Assistant, Applied Science Dep. University of Arkansas at Little Rock, 2801 South University, ETAS 555, Little Rock, AR 72204-1099, (501)569-8349, [email protected] 9 Graduate Assistant, Applied Science Dep. University of Arkansas at Little Rock, 2801 South University, ETAS 101 E, Little Rock, AR 72204-1099, (501)569-8349, [email protected] 10 PhD Candidate, Applied Science Dep. University of Arkansas at Little Rock, 2801 South University, ETAS 555, Little Rock, AR 72204-1099, (501)569-8349, [email protected]

  • NOTES

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  • 5

    HOW ENHANCED AND ECONOMICALLY VIABLE ENGINEERING ANALYSIS CAN HELP LEVEE OWNERS EVALUATE THEIR INVENTORY IN

    RESPONSE TO FEMAS PROPOSED APPROACH FOR NON-ACCREDITED LEVEES

    Todd Mitchell11

    Paul Grosskruger12 Cornelia Dean13 Bob Woldringh14

    ABSTRACT

    Our nation faces ongoing challenges to balance the dire risks of levee failures with the enormous costs in mitigating all perils. Government agencies strive to balance practical expenditures with economic loss while maintaining life safety as the top priority. Thus, many communities in the United States are burdened with the challenge of mitigating flood risks with limited time and funds, and oftentimes have no alternative but to pass this burden on to property owners through the NFIP. This issue becomes very difficult for property owners to accept when a levee exists to defend their community, yet for reasons that are frequently difficult for the layperson to understand, those levees fail NFIP accreditation requirements and are not considered in the creation of Flood Insurance Rate Maps (FIRMs). Through plans to revise its approach to levee assessment with the proposed Levee Analysis and Mapping Procedures policy (LAMP), FEMA plans to enact new provisions for characterizing these levees that fail accreditation and thus affecting property owners in these flood risk zones. However, FEMAs efforts will not fully resolve the problem. The fiscal responsibility for these newly provised characterization studies will fall directly on the levee owners. In many cases the levee owners will lack the funding to perform these studies and conduct the essential repairs necessary to make changes to the FIRM affecting landward side property owners. Similarly, many levee owners do not have the experience and knowledge to execute such studies in a way that will maximize effectiveness and contribute to a cost-effective remediation strategy. This paper explores a mechanism that shifts the paradigm from reach-level diagnosis and remediation towards a cost-comparable investigation that can result in precisely targeted remediation. FEMA, levee owners, elected officials, and all stakeholders at risk have the opportunity to benefit from a program that allows categorization of levees by FEMAs new standards while identifying how to target selective areas for specific and tailored repairs that directly impact the acceptance grading of the levee and thus affecting flood insurance premiums for landward-side property owners.

    11 Certified Mapping Scientist, Fugro Consultants, Inc., 4820 McGrath Street #100, Ventura, CA, 93003, 805-650-700, [email protected] 12 Fugro Consultants, Inc., Professional Engineer, 4651 Salisbury Road, South, Jacksonville, FL 32256, 904-253-7880, [email protected] 13 Fugro Consultants, Inc., GIS Manager , 4820 McGrath Street #100, Ventura, CA, 93003, 805-650-700, [email protected] 14 Fugro Engineers, BV, Principal Engineer, Veurse Achterweg 10, 2264 SG Leidschendam ZH, NL, +31-70-31-11157, [email protected]

  • NOTES

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  • 7

    USE OF FRAGILITY CURVES IN ASSIGNING LEVEE REMEDIATION PRIORITIES

    Rich Millet, GE, PE 15

    Sujan Punyamurthula, GE, PE, PhD 16 Derek Morley, PE 17 Loren Murray, PE 18

    Fragility curves can be defined as the relationship of the probability of failure P(f) versus some physical event or condition. In a flood protection system, the principal physical event or condition is the height of water against the levee. This paper describes the development of two simplified but pragmatic processes to develop fragility curves addressing the probability of failure P(f) versus water surface elevations (WSE) for a given levee segment/reach. Using either of these approaches, remediation needs of a levee system can be established and prioritized. The comprehensive development of probabilistic fragility curves is a complicated process and in many potential applications there is insufficient time and/or budget to complete such a rigorous task. This paper presents two simplified processes to develop fragility curves generating many of their benefits even when it is not possible to implement a rigorous probabilistic process. Processes are presented to address the cumulative potential of levee failure caused by four loading mechanisms: underseepage, through-seepage, landside slope stability, and erosion. Once fragility curves have been developed, a prioritization can be made of the reaches/segments of a leveed area with the lowest WSE for a given selected probability of failure; e.g., 5%, 50%, etc. Remediation can then be focused on these critical reaches/segments. Examples are presented to demonstrate the process.

    15 Vice President and Program Manager, URS Corporation, 2870 Gateway Oaks Dr. #150, Sacramento, CA 95833, [email protected] 16 Vice President, Deputy Program Manager, and a/e Division Manager, URS Corporation, 2870 Gateway Oaks Dr. #150, Sacramento, CA 95833, [email protected] 17 Formerly Project Manager, URS Corporation 2870 Gateway Oaks Dr. #150, Sacramento, CA 95833; currently Chief, Soil Design Section B, USACE, 1325 J Street, Sacramento, CA 95814, [email protected] 18 Senior Project Manager, URS Corporation, 2870 Gateway Oaks Dr. #150, Sacramento, CA 95833, [email protected]

  • NOTES

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  • 9

    PROBABILISTIC EVALUATION OF LEVEE DISTRESS FOR THE SACRAMENTO RIVER BANK PROTECTION PROJECT

    Khaled Chowdhury, PE, GE19

    Derek Morley, PE20 Mary Perlea, PE21

    Wilbur Huang, PE22 Matthew Weil, PE23

    Saritha Aella24

    ABSTRACT The Sacramento River Flood Control Project (SRFCP) is a system of levees, weirs, pumping plants, and bypasses designed to safely convey Sacramento River and tributary flood flows. There are about 1300 miles of project levees in this system. The Sacramento River Bank Protection Project is a federal program that inspects the SRFCP levees and associated natural banks and berms, identifying and ranking erosion problems, and providing remedial repairs. In preparation of an environmental document for the project, USACE Sacramento District required an annual exceedance probability (AEP) evaluation for erosion and other failure modes to assist in the planning process. The other failure modes for the project included underseepage, through seepage, and landside slope stability. These failure modes may lead to structural degradation of the levee, increasing the risk of failure, flood inundation, and damage to interior of levees. An innovative approach was developed to assess the AEPs of 100 erosion sites in an expedited -manner. The purpose of the evaluations was to provide AEP estimates for four specified conditions. The technical approach for the project involved document review for past performances and geologic conditions, a site reconnaissance by an engineering team using a project specific data collection method, a sensitivity study of factors affecting calculation of erosion failure mode, and review of findings. The field observations documented 13 characteristics for erosion, 8 characteristics for underseepage, 5 characteristics for through seepage, and 8 characteristics for landside slope stability. Based on these observations, a weighted site characterization score was calculated for each erosion site for erosion and other failure modes. The past performance events at the erosion sites were also evaluated for the other failure modes based on the California Department of Water Resources Urban and Non-Urban Levee Evaluations Project data. This innovative and unique approach was instrumental in implementation of the planning process of Phase II of the SRBPP.

    19 Project Manager, URS Corporation, 2870 Gateway Oaks Suite 150, Sacramento CA 95833, [email protected] 20 Chief, Soil Design Section B, USACE Sacramento District, 1325 J Street, Sacramento, CA 95814, [email protected] 21 Levee Safety Program Manager, USACE Sacramento District, [email protected] 22 Chief, USACE/CVFPB Projects Section, Department of Water Resources, 3464 El Camino Avenue, Sacramento, CA 95821, [email protected] 23 Senior Staff Engineer, URS Corporation, Sacramento, CA , [email protected] 24 Senior Staff Engineer, URS Corporation, Sacramento, CA , [email protected]

  • NOTES

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  • 11

    INTEGRATING LEVEE PERFORMANCE ASSESSMENTS INTO COMPLEX FLOOD PROTECTION SYSTEMS

    T. Mitchell25 R. Kluskens26

    B. Woldringh27 M.T. van der Meer28

    R.G. Kamp29 C. de Gooijer30 M.M. Hillen31

    ABSTRACT

    Great strides have been made in the past few years in terms of improving the characterization of levee performance and engineering assessments. The automation of several key steps in the evaluation of levees will continue to lead to improved risk assessments, targeted remediation efforts, and more effective investment by stakeholders. However, to realize the full value of these efforts, improvements in performance assessment also need to be linked to flood protection systems. The ability to identify very specific high-risk-of-failure locations on a levee can be of tremendous value to emergency management during episodic flooding hazards. Both nationally and internationally, efforts are being made to integrate the modeling of hazards of episodic events, such as hurricanes and seasonal flooding, with levee performance metrics in a dashboard environment. The dashboard will provide managers and operators of flood defense systems a powerful tool not only in their remediation planning but also in their efforts to deal with episodic flood events. Geotechnical integrity is essential for levee safety assessments. Several pilot programs have been carried out in both the USA and the Netherlands to improve the geotechnical modeling of levee strength. New insights are integrated in Fugros Rapid Engineering Assessment of Levees (REAL). REAL incorporates levee geotechnical, geospatial, and geological characteristics in its assessment and allows for systematic, consistent, and repeatable evaluation at very closely spaced cross-section intervals and various water levels. This assessment and evaluation process is typically 100 times faster than conventional work flows. This paper will elaborate on some recent developments in 3-D and real-time geotechnical and geospatial levee engineering assessments.

    25 Todd Mitchell, Fugro Consultants, USA. ([email protected]) 26 Ries Kluskens, Royal HaskoningDHV, The Netherlands, [email protected] 27 Bob Woldringh, Fugro Engineers BV, The Netherlands, ([email protected]). 28 Martin van der Meer, Fugro WaterServices, The Netherlands, ([email protected]) 29 Robert Kamp, HKV Consultants, The Netherlands, [email protected] 30 C. de Gooijer, HKV Consultants, The Netherlands, [email protected] 31 Marten Hillen, Royal HaskoningDHV, The Netherlands, [email protected]

  • NOTES

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  • 13

    UPDATED STRESS AND STABILITY ANALYSIS OF A TVA DAM

    Dan D. Curtis32 Husein Hasan33 Frank Feng34

    Bob He35 Justin Long36

    ABSTRACT

    The objective of this paper is to present a 3D stress and stability analysis of a dam that was initially analyzed using traditional two-dimensional stability analysis. The 2D stability analysis found that numerous blocks in the dam were unstable under the new PMF load condition. After further review of the initial 2D stability assessment, it was concluded that consideration of 3D behavior could reduce anchor requirements because some of the dam blocks were embedded in rock. A non-linear three-dimensional finite element model of the entire concrete dam including the intake and powerhouse was developed in the finite element program ANSYS. The model used surface contact elements at all of the vertical contraction joints in the concrete dam. These contact elements allowed relative opening/closing and sliding along these joints. In addition, similar contact elements were used at the concrete/rock interface. The model allows non-linear redistribution of forces due to opening/closing and sliding at these interface elements. The analyses considered normal, unusual and extreme loading. The results of the revised PMF analysis are presented herein. The stability of the dam was evaluated by gradually lowering the shear strength at the concrete/rock interface. An automated procedure was developed to iterate the uplift pressure as the dam/rock interface joint opened. As a result of the non-linear analysis, the anchor requirements were significantly reduced. Also, the exaggerated deformed shape of the dam clearly identified modes of failure for the entire structure. In addition, a non-linear analysis of the behavior of horizontal cracks in the spillway sluice gallery was undertaken and the results of this analysis will be presented.

    32 Project Manager, HATCH Ltd., Amherst, New York 14228-1146 USA; [email protected] 33 Civil Engineer Specialist, Tennessee Valley Authority, River Operations and Renewables /Reservoir Operations Support, Knoxville, TN 37902 USA, [email protected] 34 Senior Civil Engineer, HATCH Ltd., Amherst, New York 14228-1146 USA; [email protected] 35 Civil Engineer, HATCH Ltd., Amherst, New York 14228-1146 USA; [email protected] 36 Senior Civil Engineer, Tennessee Valley Authority, River Operations and Renewables /Reservoir Operations Support Knoxville, TN 37902 USA, [email protected]

  • NOTES

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  • 15

    AN ADVANCED MODEL FOR SIMULATION OF ASR BEHAVIOR AT ROANOKE RAPIDS DAM

    Brian R. Reinicker, P.E., P.G.37 Farzad Abedzadeh, Ph.D., P.E.38

    Robin G. Charlwood, Ph.D., P.E. 39 John A. Cima, P.E.40

    ABSTRACT

    Roanoke Rapids Dam is a 72-foot high, 3,050-foot long concrete gravity dam with four 26MW power generating units located on the Roanoke River in North Carolina. The dam was constructed in 1955 and has performed satisfactorily for most of its life. Studies performed in 2006 to 2007 discovered significant cracking along several monoliths of the upstream face of the curved portion of the South Non-Overflow Section (SNOS) and led to the conclusion that the dam is undergoing concrete expansion due to an Alkali-Silica Reaction (ASR), most notably along the dam axis. A system of crack grouting and deep, multi-strand rock anchors was designed and constructed to stabilize these monoliths and accommodate future ASR-induced expansion. During construction, the cracking was found to be more extensive than had previously been understood. A reassessment of stability mechanisms and temporary reinforcement allowed construction to continue with construction completed in May 2010. Following construction of the reinforcement, finite element modeling of the structure was initiated to more completely understand the historical behavior and provide a tool to predict future responses of the modified structure. This paper describes the initial development of an advanced ASR material model which provided a State-of-the-Practice level simulation of the ASR-induced concrete expansion behavior. The ASR material model was implemented within a finite element structural model of the full dam. Results from the finite element structural model are shared to demonstrate how the model simulates the ASR expansion behavior at Roanoke Rapids Dam from the onset of ASR effects up through the time of remediation. Comparisons between model results and historic instrumentation data are provided to demonstrate the calibration of the model with observed behavior.

    37 Senior Geotechnical Engineer, HDR Engineering, Inc., 440 S. Church Street, Charlotte NC 28202-2075, [email protected], 704.248.3693 38 Senior Geotechnical Engineer, HDR Engineering, Inc., 440 S. Church Street, Charlotte NC 28202-2075, [email protected], 704.307.8927 39 Principal, Robin Charlwood & Associates, PLLC, 4010 Alder Avenue, Freeland WA 98248, [email protected], 425.478.1642 4 Consulting Engineer, Dominion Resources Services, Inc., 5000 Dominion Boulevard, Glen Allen VA 23060, [email protected], 804.273.3045

  • NOTES

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  • 17

    INVESTIGATIONS TO EVALUATE PERFORMANCE OF CONCRETE ARCH DAM AFFECTED BY ALKALI-SILICA REACTION

    Daniel D. Mares, PE41

    ABSTRACT

    The concrete arch dam is experiencing concrete expansion, cracking and deterioration due to alkali-silica reaction (ASR). The cracking and deterioration is enhanced by freeze-thaw damage. ASR is the specific chemical reaction between the alkalis in Portland cement and silica or silicates in the aggregate which, in the presence of moisture, forms a hydrophilic expansive ASR gel. The gel absorbs moisture and swells which results in cracking and expansion of concrete structure. The reactive aggregate has been identified as strained quartz, which was the coarse aggregate used in concrete mix during dam construction. Strained quartz is known to be associated with late reacting ASR. Evidence of the concrete expansion was observed at this arch dam in the late 1970's when structure deformation data collection was initiated. The concrete deterioration includes spalling, pattern cracking, de-bonding of coarse aggregates from the remaining concrete, and calcium carbonate deposits on exposed concrete surfaces. This paper summarizes the investigation and analyses that have been performed since the late 1990s. Investigations have included concrete coring and testing, petrographic examinations, seismic tomography, borehole geophysics, in-situ stress measurements, and deformation monitoring on the concrete dam and rock abutments. A structural analysis was performed to estimate present and future stress conditions at the dam. In-situ stress measurement data and deformation data were used to calibrate the structural analysis model. The analysis indicated that the upward expansion and upstream tilt of the dam would result in large upward reaction forces in the upper abutments.

    41 Daniel D. Mares, P.E., Civil Engineer, Waterways and Concrete Dams Group, Bureau of Reclamation, [email protected]

  • NOTES

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  • 19

    STRUCTURAL ANALYSIS OF CORBELS ON AN AGING MULTIPLE-ARCH DAM

    Brad B. Watson, P.E. 42

    Victor M. Vasquez, P.E.43 Les Boyd, P.E.44

    Doug Witkowski, P.E.45 James O. Jirsa, Ph.D., P.E.46

    ABSTRACT

    Buchanan Dam, owned by the Lower Colorado River Authority (LCRA), is a 145-ft high, multiple-arch dam on the Colorado River. Completed in 1937 and stretching more than two miles, Buchanan Dam is considered the longest multiple-arch dam in the nation. The dam includes two multiple-arch sections with 35-foot and 70-foot diameter arches. As part of a comprehensive facility review, analyses of the arch sections were performed. As often occurs when re-analyzing old structures using current criteria, some results were unsatisfactory. The corbels on the buttresses supporting the arches were found inadequate in both strength and ductility. A risk assessment of the structure indicated the need for action. Expenditure for enhancing corbel capacity was estimated between $15 and $30 million. LCRA engaged Freese and Nichols, Inc. to perform in-depth evaluations before proceeding with such significant construction expenditures. The corbels were first reevaluated using American Concrete Institute (ACI) methodology. Due to differences between the ACI code provisions and the corbel geometry and reinforcement, these results were deemed inconclusive. As a result, 2-D finite element models were developed; however, the adequacy of the corbels could not be substantiated without additional information. Additional inspections of the corbels through visual observations and underwater video found no visible signs of cracking that would suggest overstressing. Also, a physical model study was conducted by constructing and testing two half-size specimens of a representative corbel section. The tests indicated that shear failure was unlikely. Failure was due to tensile cracking of the concrete section followed by ductile yielding of the steel reinforcement at the face of the corbels. Results of the physical tests were then used to develop refined analytical models. The analytical model results demonstrated the corbel had adequate strength to resist anticipated loads. Ultimately, the structure was deemed safe and a large expenditure was avoided through careful engineering.

    42 Senior Structural Engineer, Freese and Nichols, Inc., [email protected] 43 Project Manager, Freese and Nichols, Inc., [email protected] 44 Senior Structural Engineer, Freese and Nichols, Inc., [email protected] 45 Principal Engineer, Lower Colorado River Authority, [email protected] 46 Professor - Janet S. Cockrell Centennial Chair in Engineering, University of Texas at Austin, [email protected]

  • NOTES

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  • 21

    INTEGRATING INFRASTRUCTURE UPGRADES WITH GRAVITY DAM REPAIRS

    Timothy W. Johnston, P.E.47

    John A. Wilkes, P.E.48 Mishelle Noble-Blair49

    Thomas B. Pursel, P.E.50

    ABSTRACT The Upper Occoquan Dam, a 72-foot high, 1950s vintage concrete gravity dam located on the Occoquan River, is one of two primary sources of municipal water supply for Fairfax Water, which serves nearly 1.7 million people in Northern Virginia. Although the primary purpose of the dam and reservoir is municipal water supply, the Federal Energy Regulatory Commission (FERC) has regulated this facility due to the presence of a hydroelectric plant. In 2005, as part of FERCs potential failure modes analysis process, recommendations were made to conduct investigations and prepare alternatives for dam safety repairs to significant cracks in the 72-foot-high powerhouse intake wall. This paper discusses the engineering investigations and development of repair alternatives to address the structural cracks in the powerhouse intake wall, including eliminating the seepage that was occurring through the wall. An innovative and cost-effective solution that addressed both dam safety concerns and a need to upgrade the powerhouse intake structure to an outlet works that met current industry standards for reservoir emergency draw down was selected. Structural and stability concerns were addressed by placing mass concrete within interior wet well chambers and multi-level portals of the powerhouse intake. Outlet works capacity was increased by encasing four large diameter steel conduits within the mass concrete backfill and adding a new gated concrete control tower to regulate discharge. The potential for seepage paths to develop through the new mass concrete backfill was minimized by the underwater installation of a PVC geocomposite membrane liner waterproofing system on the upstream face of the intake structure. The upgrades and repairs were accomplished without lowering the reservoir level expanding the dams footprint or impacting the water supply. The project also included hydroelectric plant demolition and FERC license surrender.

    47 Project Manager, Associate, Gannett Fleming, Inc., Camp Hill, PA 17011, [email protected] 48 Carpi USA Inc., Roanoke, VA 24018, [email protected] 49 Senior Plant Engineer, Fairfax Water Treatment Plant, Lorton, VA 22079, [email protected] 50 Vice President, Gannett Fleming, Inc., Camp Hill, PA 17011, [email protected]

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  • 23

    EXPLICIT SEISMIC ANALYSIS OF MOSSYROCK DAM

    Dan D. Curtis51 Gurinderbir Sooch52 Toby Brewer, P.E.53

    Andrew Schildmeyer, P.E.54

    ABSTRACT Hatch Associates Consultants Inc. was retained by Tacoma Power, located in Washington State to perform an explicit seismic analysis of Mossyrock Dam. A finite element model was then developed for the arch dam and its foundation rock which includes the effects of dam-foundation-reservoir interaction. Non-reflecting absorbing boundaries were modeled along the foundation sides and also at the extents of the reservoir. The vertical contraction joints and the dam-foundation interface were modeled with contact surfaces capable of opening, closing, and sliding during an earthquake. The shear strength of the dam-foundation interface included only a frictional component of shear strength i.e., cohesion was neglected. The new seismic analysis of Mossyrock Dam indicates that the total deflections, accelerations, and stresses calculated using the LS-DYNA finite element model are significantly smaller than those determined with a previous, implicitly solved, ANSYS model. Also, the model was used to check the response with a known recorded earthquake at Mossyrock Dam. Because this new model appears to attract less load than the previous analysis, no tension cracks in the horizontal lift joints are now expected where the previous analysis indicated such problems would occur. However, the results of the new analysis indicated relatively large hydrodynamic loads act on the radial gates at the top of the dam when compared to the hydrodynamic loads computed using the Westergaard method.

    51 Project Manager, Hatch Associates Consultants, Amherst, New York 14228-1146, USA and Hatch Ltd, Niagara Falls, Canada, [email protected] 52 Civil Engineer, Hatch Ltd, Niagara Falls, Canada, [email protected] 53 Chief Dam Safety Engineer, Tacoma Power, Tacoma, Washington, [email protected] 54 Professional Engineer, Tacoma Power, Tacoma, Washington, [email protected]

  • NOTES

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  • 25

    STRENGTH MONITORING FOR RCC DAM DURING CONSTRUCTION

    James Stiady55 Frank Collins56

    Jim Zhou57 Gerard E. Reed III58

    Wade Griffis59 Jeffrey A. Shoaf60

    ABSTRACT

    The San Diego County Water Authority (Water Authority) is currently undertaking the raise of the existing San Vicente Dam to provide both emergency and carryover storage to increase local reservoir supplies in San Diego County, California. The San Vicente Dam is part of the $1.5 billion Emergency Storage Project (ESP) and Carryover Storage Project (CSP) which will provide a more flexible conveyance system, and increase water supply reliability in case of catastrophic failure to the delivery system due to a major earthquake. The San Vicente Dam Raise (SVDR) project is a major component of the last phase of the ESP and consists of raising the existing 220-foot high gravity dam with 90,063 acre-feet of storage, by 117-feet to increase reservoir storage capacity by 152,000 acre-feet. Scheduled to be completed in 2013, the SVDR will be the tallest dam raise in the United States and tallest roller compacted concrete (RCC) dam raise in the world. The reservoir capacity will be more than doubled, making it the largest single increase in water storage in this regions history. In this paper, the use of 7-day strength for confirming the RCC mix that had been placed and identifying the necessary adjustment for the subsequent RCC production is discussed. The confirmation purpose was achieved by monitoring the 7-day strength as the construction progressed and developing boundary to identify the outliers. The outliers were evaluated further in accelerated testing. The need for adjustment was evaluated by observing a developing pattern in the 7-day strength historical plot.

    55 Kleinfelder, 5015 Shoreham Place, San Diego, CA, 92122; 858-320-2269, [email protected] 56 Parsons, 110 West A Street, Suite 1050, San Diego, CA, 92101; 858-342-9813, [email protected] 57 San Diego County Water Authority, 4677 Overland Avenue, San Diego, CA , 92123, 858-522-6837, [email protected] 58 San Diego County Water Authority, 4677 Overland Avenue, San Diego, CA , 92123, 858-522-6835, [email protected] 59 San Diego County Water Authority, 4677 Overland Avenue, San Diego, CA , 92123, 619-390-2310 x3206, [email protected] 60 San Diego County Water Authority, 4677 Overland Avenue, San Diego, CA , 92123, 858-522-6813, [email protected]

  • NOTES

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  • 27

    PRACTICAL APPLICATION OF RFC DAM CONSTRUCTION BASED ON CHEAP MIX DESIGN OF SCC

    Qiong Wu 61 Xuehui An 62

    Miansong Huang63 Feng Jin64

    ABSTRACT

    Rock-Filled Concrete (RFC) is an innovative dam construction material which has been developed quickly in China since 2003. The concrete is produced by pouring the Self-Compacting Concrete (SCC) into the voids of large rock chunks, with a minimum size of 300 mm, in a formwork. We have employed two different RFC construction technologies in a number of hydraulic engineering structures in China. To date, all the practical applications have shown that using RFC in dam constructions has significant economic and environmental benefits. Total construction cost is reduced due to using large amount of rock chunks, which can amount to roughly 55% of the total volume of RFC. When producing SCC, we make full use of local raw materials (e.g. fly ash, limestone) and optimize mix design to obtain better workability and lower cost. With regard to energy consumption and greenhouse gas emissions, RFC method consumes less energy and generates significantly fewer emissions when compared with Conventional Concrete from materials manufacturing through the concrete casting phase. Moreover, applying RFC brings about quicker construction due to the omission of surface roughening and allowance for continuous SCC pouring. Further, RFC saves on labor and costs by simplifying the aggregate production, concrete mixing machinery and temperature control facilities, as well as eliminating the vibration process. Lastly, it is indicated that RFC is a potential and promising material for use in future concrete dams.

    61 Ph.D candidate, Department of Hydraulic Engineering, Tsinghua University, Beijing, 100084, China, [email protected] 62 Professor, Department of Hydraulic Engineering, Tsinghua University, Beijing, 100084, China, [email protected] 63 Post-doctoral, Department of Hydraulic Engineering, Tsinghua University, Beijing, 100084, China, [email protected] 64 Professor, Department of Hydraulic Engineering, Tsinghua University, Beijing, 100084, China, [email protected]

  • NOTES

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  • 29

    FILLING AN EXPANDED RESERVOIR A MYRIAD OF CONSIDERATIONS Kelly L. Rodgers, P.E.65 Gerard E. Reed III, P.E.66 Jim Zhou, P.E.67 Surraya Rashid, P.E.68 Rosalva Morales69 Thomas O. Keller, P.E., G.E.70

    Anna E. Kolakowski, P.E.71

    ABSTRACT The San Diego County Water Authority (Water Authority) is a public agency that imports up to 80 percent of the regions water supply. The pipelines conveying imported water to the County cross several major fault lines. In 1998, the Water Authority approved a $1.5 billion Emergency Storage Project (ESP) to increase local storage and provide a more flexible and effective conveyance system. The San Vicente Dam Raise (SVDR) project is a major component of the last phase of the ESP and consists of raising the existing 220-foot-high dam by 117 feet to increase reservoir storage capacity by 152,000 acre-feet (AF). The SVDR will be the tallest dam raise in the United States and tallest roller compacted concrete (RCC) dam raise in the world. The City of San Diego (City) is a key partner, as it owns and operates the San Vicente Dam and Reservoir. Recognizing the regional benefit to the expansion of San Vicente Reservoir (SVR), the Water Authority and City executed an agreement that outlines the obligations of each party to bring the SVDR project to fruition. Once the dam raise is complete in 2013, and in coordination with the California Department of Water Resources Division of Safety of Dams, the Water Authority will begin filling the reservoir to its new, more than doubled, capacity. The fill is planned in four phases. Considerations include limitations imposed by the strength gain of the new RCC, reservoir hold points for monitoring of dam performance, constraints imposed by other construction activities at the site, capacity of the pipelines that bring water to the reservoir, and imported water supply availability. Finally, the Water Authority must account for member agency demands for SVR supplies as well as other commitments to customers.

    65 Senior Engineer, San Diego County Water Authority, 4677 Overland Avenue, San Diego, C 92123-1233, [email protected] 66 Engineering Manager, San Diego County Water Authority, 4677 Overland Avenue, San Diego, California 92123-1233, [email protected] 67 Engineer PE, San Diego County Water Authority, 4677 Overland Avenue, San Diego, California 92123-1233, [email protected] 68 Senior Civil Engineer - Civil, City of San Diego, 2797 Caminito Chollas, San Diego, California 92105-5097, [email protected] 69 Associate Engineer - Civil, City of San Diego, 2797 Caminito Chollas, San Diego, California 92105-5097, [email protected] 70 Vice President, GEI Consultants, Inc., 2141 Palomar Airport Road, Suite 160, Carlsbad, California 92011-1463, [email protected] 71 Senior Engineer, California Department of Water Resources Division of Safety of Dams, 2200 X Street, Suite 200, Sacramento, California 95818, [email protected]

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  • 31

    DAM BREAK ANALYSIS APPLIED TO TAILINGS DAMS: USSD WORKSHOP SUMMARY AND PERSPECTIVES

    Jos L.M. Clemente72

    Robert E. Snow73 Carmen Bernedo74

    Clinton L. Strachan75 Andy Fourie76

    ABSTRACT

    The USSD Tailings Dams Committee organized a workshop in August 2011 that included 2 days of presentations and discussions on the topic of dam break analysis applied to tailings dams and possible applications to other slurried waste impoundments. The workshop presentations covered the following main topics: (1) regulatory aspects of dam break analysis applied to tailings dams, (2) predictive models and available software, (3) failure modes, and (4) tailings flow modeling after a potential dam break. A survey was developed and distributed to state and federal dam safety officials to seek feedback on regulatory aspects of dam break analysis applied to tailings dams. This manuscript provides a workshop summary that can be seen as the framework for a state-of-practice document. The purpose(s) of break analysis, methods used, and documentation of important assumptions are addressed. Commentary citing concerns raised during and after the workshop are also included as it was clear that our ability to conduct accurate and realistic dam break analyses is limited. This manuscript also attempts to outline directions for the focus of future research and development projects with the goal of establishing more realistic methods for tailings dam break analysis.

    72 Chief Engineer, Geotechnical & Hydraulic Engineering Services, Bechtel Power Corporation, Frederick, MD, USA, [email protected] 73 Principal, DAppolonia Engineering, Monroeville, PA, USA, [email protected] 74 Lead/Supervising Engineer, MWH Global, Inc., Denver, CO, USA, [email protected] 75 Principal Geotechnical Engineer, MWH Americas, Inc., Fort Collins, CO, USA, [email protected] 76 Professor, School of Civil and Resource Engineering, University of Western Australia, Perth, WA, Australia, [email protected]

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    DESIGN, CONSTRUCTION, AND PERFORMANCE OF A SEEPAGE CUTOFF BARRIER IN A DAM

    Ivn A. Contreras, PhD., P.E.77

    Jon D. Ausdemore, P.E.78 Joe A. Welna79

    Rachel E. Franz80

    ABSTRACT A tailings basin at a trona mine near Green River, Wyoming includes approximately two miles of earthen containment structures around the perimeter of the basin. The containment system has a documented history of seepage and sinkhole development which raised safety and environmental concerns. In attempts to mitigate seepage, a soil-mix cutoff wall was built. The soil-mix wall reduced some of the seepage through the overburden embankment material but did not extend deep enough into the underlying fractured rock which allowed pond water to flow under the dam foundation. As a result, a complementary permeation grouting program was initiated to create an effective cutoff under the soil-mix wall and within the fractured rock foundation to reduce the seepage and improve the overall stability. This paper describes a detailed history of the geology and seepage issues at the site, the soil-mix wall, the grouting program, and the construction and monitoring of the seepage barrier that effectively mitigated the safety and environmental concerns. In particular the design, construction, and performance of the seepage barrier are discussed in detail.

    77 Senior Geotechnical Engineer; Barr Engineering Co., Minneapolis, MN; 952-832-2600; [email protected] 78 Senior Civil Engineer; Barr Engineering Co., Minneapolis, MN; 952-832-2600; [email protected] 79 Civil Engineer; Barr Engineering Co., Minneapolis, MN; 952-832-2600; [email protected] 80 Civil Specialist; Barr Engineering Co., Minneapolis, MN; 952-832-2600; [email protected]

  • NOTES

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  • 35

    SEISMIC DESIGN OF PERIMETER SLURRY WALLS FOR THE KINGSTON COAL ASH POND CLOSURE

    Alan F. Rauch, PhD, PE81

    Rodney P. McAffee, PhD, PEng82 Yong Wu, PhD, PE83 Luis J. Arduz, PE84

    ABSTRACT

    Using slurry wall methods, a stabilized perimeter is being constructed around the two-mile circumference of the coal ash landfill at TVAs Kingston, Tennessee, facility. The landfill is being built within the footprint of the ash impoundment that experienced a catastrophic, static liquefaction failure in December 2008. When complete, the new capped facility will contain roughly 12 million cubic yards of coal ash produced by the power plant over the last six decades, including ash recovered from the 2008 failure. The closed facility is designed to meet current regulatory requirements, and must withstand a 2,475-year seismic event. The lower deposits of coal ash will remain saturated and, like the deeper alluvial sands beneath the site, will liquefy in the design earthquake. The stabilized perimeter, consisting of a grid of walls beneath a new perimeter berm, will buttress the ash embankment and retain the liquefied ash under dynamic loading. Currently under construction, self-hardening, cement bentonite and slurry trench methods are being used to build the walls. Similar designs have been used to stabilize major embankment dams with liquefiable foundation deposits. This paper focuses on the engineering analyses used to design the perimeter containment, including: geologic and subsurface conditions, ground response and liquefaction analyses, slope stability analyses, dynamic simulations of liquefaction and seismic performance, structural modeling in three dimensions, and embedment of the wall base into bedrock.

    81Stantec, Inc., 1409 North Forbes Road, Lexington, Kentucky, 40511, [email protected] 82C-CORE, Capt. Robert A. Bartlett Building, Morrissey Road, St. John's, Newfoundland, [email protected] (formerly with Stantec). 83Stantec, Inc., 1859 Bowles Ave. Suite 250, St. Louis, Missouri, 63026, [email protected] 84Stantec, Inc., 1409 North Forbes Road, Lexington, Kentucky, 40511, [email protected]

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  • 37

    PERFORMANCE OF PREWETTED LOESS FOUNDATIONS FOR EMBANKMENT DAMS

    William O. Engemoen85

    ABSTRACT

    During its history, the Bureau of Reclamation (Reclamation) has built several dams on foundations which consisted in part or totally of loess and reworked loess materials. The loess encountered in these foundations typically consists of dry, low-density silts which when loaded are susceptible to significant collapse upon wetting. One of the methods Reclamation has used to treat these problem soils has been to prewet the materials prior to placing the embankment so that the majority of the settlement will take place during construction rather than upon reservoir filling. This method was frequently used in the 1940s through the 1960s. Four Reclamation dams from that era that utilized prewetting were studied in order to evaluate the performance of the prewetting operations. Settlement data from baseplates and cross arm devices were examined to determine the rates and amounts of settlement. At three of the four dams studied, prewetting was relatively successful in that 70 to 95 percent of the total settlement occurred during construction. One of the four dams, however, experienced as much as 55 percent of the total settlement during and after initial reservoir filling. Even on successful prewetting operations, significant post-construction settlement still occurred (up to 30 percent of the total settlement), generally occurring during first filling. The settlement data obtained from these instrumented dams were plotted to obtain a graph of settlement versus embankment height with varying thicknesses of loess, which provides a means for approximating anticipated total settlements for embankments constructed on loess foundations that will eventually become saturated.

    85 Lead Civil Engineer Geotechnical Services Division, Bureau of Reclamation , P.O. Box 25007, Code 86-68300, Denver, CO 80225, (303) 445-2960, [email protected]

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  • 39

    ERODABILTY OF SEEPAGE BARRIER MATERIALS

    Nathan Braithwaite86 John Rice87 David Paul88

    ABSTRACT

    Seepage barriers (cutoff walls) are used extensively to retard seepage in dams and levees and to reduce the potential for seepage related erosion. A variety of materials are used as backfill for these barriers including: soil-cement constructed using a variety of proprietary methods, cement-bentonite (self-hardening slurry), soil-bentonite, plastic concrete, and conventional concrete. Recent studies and post-construction observations have indicated that cracking of seepage barriers is not uncommon due to wall deformation, thermal expansion, and contraction during curing. It is theorized that such cracks in some of the barrier materials listed above may be susceptible to erosion due to high velocity seepage flow caused by large differential pore pressures across the barriers. A laboratory modeling study is being performed to evaluate the erodability of a variety of barrier materials commonly used in current seepage barrier construction and to assess the potential for erosion to initiate and propagate in various configurations of adjacent soils. The study consists of two phases of laboratory modeling. Phase 1 evaluates the erodability of a wide range of seepage barrier materials under the hydraulic conditions (pressure and gradient) expected to be encountered in the field. The tests are performed by passing water through cracks formed longitudinally through 6-inch diameter by 12-inch long cylindrical samples of the barrier matertials. Because no soil is adjacent to the barriers, these tests measure the basic erodibilty of the barrier material. Phase 1 tests are being performed on samples of cement bentonite, soil cement, plastic concrete, and conventional concrete. The Phase 2 testing is being performed in a laboratory model where the barrier cracks are adjacent to a variety of soils and soil configurations. Models are tested using barrier materials found to be erosive in the Phase I testing. This modeling assesses the interaction of the eroding barrier material and the adjacent soils and evaluates the effects of processes such as filtering of the eroding particles and filling of the barrier cracks with soil. The results of both phases of modeling will be used to evaluate the potential for seepage barrier cracks to develop into more serious seepage problems.

    86 Graduate Student, Utah State University, 4110 Old Main Hill, Logan, UT 84322, [email protected], 435-225-0911 87 Assistant Professor, Utah State University, [email protected], 435-797-8611 88 Construction Liaison, USACE Risk Management Center, 12300 W. Dakota Ave Suite 230, Lakewood, CO 80228, [email protected], Phone 720-289-9042.

  • NOTES

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  • 41

    BLUE LAKE DAM LEFT ABUTMENT STABILIZATION DESIGN James H. Rutherford, P.E., P.Eng.92 Peter Friz, P.Geo., LG93 John Werner, E.I.T.94 Lingmin Feng, PhD, P.Eng.95

    Jerry Higgins, PhD, P.G.96

    ABSTRACT The height of the existing Blue Lake arch dam is 211 feet (64.3 m). The Blue Lake Expansion Project includes an 83 ft (25.3 m) dam raise. This paper presents the full range of civil, structural, and geotechnical analyses performed to design the left abutment of the raised dam. Challenges included design of a thrust block acting as a strut to transfer dam loads to bedrock with topography that drops away steeply at the dam contact; a cut-off wall to prevent the thrust block from being subject to hydrostatic loading and prevent seepage; and developing an approach to stabilizing rock blocks subject to significant dam thrust under a variety of load cases and boundary conditions. The various rock blocks were modeled using AutoCAD 3D as an analysis tool to determine the mass of the various blocks, extent and direction of hydrostatic loads on the block faces, and orientation of dam thrust loads relative to inertial and hydrostatic loading. The dam raise design required comprehensive non-linear time history finite element analyses to check the stresses for the dam. These analyses were used to design the dam structure and determine the forces from the dam acting on the left abutment for use in block stability analysis and design of the thrust block. The thrust block and rock stabilization design were based on worst case boundary condition assumptions. An economical design has been developed for the left abutment based on a state-of-the-art nonlinear dynamic analysis of the raised dam, an innovative approach to analyzing rock blocks subject to dam loading and careful design of the thrust block and cut-off wall. The left abutment design will be adjusted as new information becomes available from the exposure of subsurface rock from thrust block, dam abutment, and drainage tunnel excavations during construction.

    92 Civil Structural Engineering Lead, HATCH Renewable Power, 6 Nickerson Street, Suite 101, Seattle, WA 98109, Tel: 206-352-5730; Fax 206-352-5734; email: [email protected] 93 Engineering Geologist, HATCH Renewable Power, 700 - 1066 West Hastings Street, Vancouver, B.C, Canada V6E3X2, Tel: 604-630-7354; Fax 604-683-9148; email: [email protected] 94 Civil Structural Engineer, HATCH Renewable Power, 6 Nickerson Street, Suite 101, Seattle, WA 98109 Tel: 206-352-5730; Fax 206-352-5734; email: [email protected] 95 Senior Structural Analyst, HATCH Renewable Power, 4342 Queen Street, P. O. Box 1001, Niagara Falls, Ontario, Canada L2E6W1,Tel: (905) 357-6998 ; Fax ; email: [email protected] 96 Professor, Department of Geology and Geological Engineer, Colorado School of Mines, 1516 Illinois Street, Golden Colorado 80401, Tel: (303) 273-3817; email: [email protected]

  • NOTES

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    PERFORMANCE OF RCC STRENGTHENED LEVEE IN FULL-SCALE OVERTOPPING TESTS

    Farshad Amini, PhD, PE, F.ASCE97

    Lin Li, PhD, PE, M.ASCE98

    ABSTRACT Most earthen levee damages have occurred on the levee crest and landward-side slope after Hurricane Katrina as a result of either wave overtopping, storm surge overflow, or a combination of both. The goal of this study was to investigate the performance and develop design guidelines for crest and landward-side strengthening system Roller Compacted Concrete (RCC). A full-scale experimental study on combined wave and surge overtopping of a levee armored with RCC was conducted in a two-dimensional laboratory wave/flow flume. Trials of surge-only overflow, wave-only overtopping, and combined wave overtopping and surge overflow with different combinations of upstream head, significant wave height and peak period were conducted on the RCC section. The overtopping hydraulic features were summarized during the tests. Time series of flow thickness and velocity on the levee crest and landward-side slope were measured. Pre-selected locations were investigated to determine erosion in the RCC section. Erosion of RCC surface was checked after each test. It was found that most of the erosion occurred after the first test and the erosion was related to initial quality of RCC surface. Flow parameters including time series of flow thickness and velocity at 5 locations on the levee crest and landward-side slope were measured. New equations were developed to estimate flow parameters on landward-side slope, including mean flow thickness, mean velocity, and wave front velocity for the RCC strengthened levee.

    97 Department of Civil and Environmental Engineering, Jackson State University, Jackson, MS 39217, USA. 601-9793913, [email protected] 98 Department of Civil and Environmental Engineering, Jackson State University, Jackson, MS 39217, USA. 601-9791092, [email protected]

  • NOTES

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  • 45

    SCOUR OF DISCONTINUOUS BLOCKY ROCK

    Michael F. George99 Nicholas Sitar100

    ABSTRACT

    Removal of individual rock blocks is one of the principal mechanisms by which scour can occur, particularly in unlined spillways and on dam abutments. To alleviate some of the complexity, commonly used methods for scour prediction tend to simplify the rock mass using rectangular block geometries or incorporate empirical relationships for the rock mass and do not actually model the physical scour process. Such simplifications can be problematic, particularly for block analysis, where the 3D orientation of discontinuities within the rock mass largely influence block removability. To better represent the 3D structure of the rock mass, block theory has been applied to evaluate stability of removable rock blocks subject to hydraulic forces. Block theory provides a rigorous methodology to identify removable blocks, determine potential failure modes, and assess block stability. This paper presents methodologies for application of block theory to scour analysis of an actively eroding unlined rock spillway at a dam site in Northern California.

    99 University of California - Berkeley, 413 Davis Hall, Berkeley, CA 94720, [email protected] 100 University of California - Berkeley, 449 Davis Hall, Berkeley, CA 94720, [email protected]

  • NOTES

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    FINITE ELEMENT MODELING OF TRUNNION RODS

    Mark A. Cesare, Ph.D.101 J. Darrin Holt, Ph.D., P.E.102

    Robert F. Lindyberg, Ph.D., P.E.103 Jim J. Lua, Ph.D.104

    Xiujun Fang, Ph.D.105

    ABSTRACT This paper describes an approach for experimentally calibrating a three-dimensional (3D) finite element model (FEM) of in-situ trunnion rods to a series of full-scale tests using a full-size trunnion anchor prototype. The FEM is used to predict the modal responses of a rod as tension increases. The prototype is then loaded to known stress levels and experimentally evaluated for its responses by placing vibration transducers on the rod. The measured responses are then used to fine-tune the FEM approach by changing material properties and adjusting details of the known threads and rod gripping devices. Ultimately, this approach could serve as a basis for calibration of models to determine tension from only vibration tests, thereby eliminating the need for rod manual lift-off testing.

    101 FDH Engineering, Inc., 2730 Rowland Road, Raleigh NC 27616, [email protected] 102 FDH Engineering, Inc., 2730 Rowland Road, Raleigh NC 27616, [email protected] 103 FDH Engineering, Inc., 2730 Rowland Road, Raleigh NC 27616, [email protected] 104 Global Engineering and Materials, Inc., 1 Airport Place, Suite 1, Princeton, NJ 08540, [email protected] 105 Global Engineering and Materials, Inc., 1 Airport Place, Suite 1, Princeton, NJ 08540, [email protected]

  • NOTES

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    EFFECTS OF BRONZE AND COMPOSITE SLEEVES ON TRUNNION YOKE PLATE STRESS CONCENTRATIONS

    Thomas J. Walker, M.S., P.E.106

    Kevin Z. Truman, Ph.D.107 Kurt A. Jacobs, M.S., P.E.108

    ABSTRACT

    Nonlinear simulations were used to predict and further understand the load transfer between trunnion shafts and yoke plates within a tainter gate trunnion assembly. Traditionally, yoke plates have been sized for an average stress based on the projected bearing area between the trunnion shaft and the yoke plate; however, finite element analyses proved that the stress is not uniform across the thickness of the yoke plate. The non-uniform stress distribution is attributed to the transverse shaft rotations that exist at the supports, concentrating load on the inboard edges of the yoke plates. Further study showed that the installation of either a bronze or composite sleeve between the yoke plate and the trunnion shaft will reduce the magnitude of the stress concentrations. A series of finite element models was developed to investigate the effects that shaft diameter, yoke plate thickness, and sleeve material have on the trunnion shaft to yoke plate load path. The analyses showed that a trend can be identified between the magnitude of the edge stress and the L/D ratio (shaft clear span to shaft diameter). As the L/D ratio of the system is increased, the magnitude of the edge stress increases; however, when a sleeve with a lower modulus of elasticity is introduced into the system, it is observed that the magnitude of the edge stress is reduced. The L/D ratio is designed to be close to 1.0 in order to minimize the inboard edge stress; however, trunnion assemblies with larger L/D ratios are desirable from a tainter gate design perspective. Larger clear spans (L) simplify the connection between the strut arms and the trunnion assembly, and small shaft diameters (D) reduce the trunnion pin friction moment demand on the tainter gate strut arms. By installing a low modulus sleeve between the trunnion shaft and the yoke plate, the magnitude of the edge stress is reduced; therefore, the design can accommodate L/D ratios larger than 1.0 while still keeping the stresses below an acceptable level. The simplified detailing and the reduction in strut arm demand will produce a more cost effective tainter gate design.

    106 Structural Engineer, Black & Veatch Corporation, Water Division, [email protected] 107 Dean & Professor of Civil Engineering, University of Missouri-Kansas City, [email protected] 108 Structural Engineer, U.S. Army Corps of Engineers, [email protected]

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    HODENPYL HYDROELECTRIC PLANT SPILL TUBE HEADGATE REPLACEMENT PROJECT

    Tor Hansen, P.E.109

    Adam Monroe, P.E.110 Rusty Friedle111

    ABSTRACT

    This paper summarizes a design-build project to replace spill tube headgates at the base of the Hodenpyl Hydroelectric Plant. The spill tubes are hydraulic conduits under the powerhouse that provide additional spill capacity during flood events. The authors companies teamed to design and replace the existing 80-year-old Broome gates which leaked severely. The leakage (estimated to be on the order of 300 cfs) was costing the owner in lost generation revenue. The new roller gates were designed to seat under gravity loads and maintain their seal under approximately 65 feet of hydraulic head. Each gate was sized to overcome the frictional forces acting to resist gate movement, including hydrostatic, hydrodynamic, and atmospheric pressures. In order to reduce the hoist load needed to operate the gate, low-friction self-lubricating bronze bearings in the wheels and Teflon-coated rubber J-seals on the gate were used. The gate was designed for the existing hoist with a factor of safety to assure the gate would operate. Structural modifications to the 9-foot-high by 12.5-foot-wide spill tube inlet to create sealing surfaces for the new gate seals were also designed and constructed. This work included construction of new reinforced concrete sills, jambs, and headers around the inlet with embedded stainless steel plates for sealing. The existing gate slots were also modified by adding a rail to bear the new roller gate wheels. To facilitate the work, a steel stoplog cofferdam and bracing system were also designed and constructed. The design included various-sized (depending on head) fabricated beams to limit defection and prevent impact to the existing trash rack. The cofferdam was installed and used under 65 feet of water.

    109 Vice President, Barr Engineering Company, 4700 West 77th Street, Minneapolis, MN 55435, [email protected] 110 Dam Safety Engineer, Consumers Energy, 330 Chestnut Street, Cadillac, MI 49601, [email protected] 111 Project Manager, Gerace Construction, 4055 South Saginaw Road, Midland, MI 48640, [email protected]

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    INUNDATION MAPPING FOR IMPENDING RECORD RESERVOIR RELEASES MISSOURI RIVER FLOOD OF 2011

    Thomas Gorman, P.E.112 Lowell Blankers, P.E.113 Laurel Hamilton, E.I.114 Colleen Horihan, P.E.115 Troy Ingram116 Tony Krause, P.E.117 Curtis Miller, P.E.118 Eric Morrison119 Michelle Schultz120 Megan Splattstoesser121

    Neil Vohl, P.E.122

    ABSTRACT The U.S. Army Corps of Engineers operates six mainstem dams and reservoirs on the upper Missouri River. In the spring of 2011, record run-off required large releases from the system. As the magnitude of the impending flooding became apparent, Corps officials decided that producing inundation mapping for the predicted releases would be of immense value to communicate the flood risk. Modeling and mapping methods developed by the Corps Mapping, Modeling and Consequences Production Center for rapid assessment of dam safety scenarios were used to develop inundation mapping extending about 1,270 river miles. This paper will provide background on the flood event and the Omaha Districts effort to develop more than 300 detailed flood inundation map panels in advance of damaging flooding. The distribution and dissemination of the information to federal agencies, states, communities, tribes, news media and the public will be discussed. Finally, the projected flooding will be compared with what actually occurred.

    112 Hydraulic Engineer, U.S. Army Corps of Engineers, Omaha District, Omaha, NE, 68102, [email protected] 113 Hydraulic Engineer, U.S. Army Corps of Engineers, Omaha District, Omaha, NE, 68102, [email protected] 114 Hydraulic Engineer, U.S. Army Corps of Engineers, Omaha District, Omaha, NE, 68102

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