1 / 52

Pre-Design Geotechnical Evaluation of the OII Superfund Site

Pre-Design Geotechnical Evaluation of the OII Superfund Site. 11th th Ralph B. Peck Lecture by Edward Kavazanjian, Jr. Ph.D., P.E. Arizona State University for WasteMINZ New Zealand 15 October 2009. Ralph B. Peck (1912-2008).

morrison
Download Presentation

Pre-Design Geotechnical Evaluation of the OII Superfund Site

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Pre-Design Geotechnical Evaluationof the OII Superfund Site 11thth Ralph B. Peck Lecture by Edward Kavazanjian, Jr. Ph.D., P.E. Arizona State University for WasteMINZ New Zealand 15 October 2009

  2. Ralph B. Peck (1912-2008)

  3. The Operating Industries, Inc. Landfill“A unique urban hazard”

  4. A Unique Urban Hazard Hazardous Waste Steep North Slope • 60 m-tall, 1.5H:1V • Adjacent to SR-60 (Pomona Freeway) Proximity to Homes to the South • MSE Toe Buttress Seismic Exposure

  5. Steep North Slope, Freeway Proximity 1.5H:1V average, 1.3H:1V maximum slope, rising 60 m above grade

  6. South Slope Toe Buttress (1987)

  7. 1987 Whittier M 5.9 Narrows Earthquake The “Big Bend”

  8. Earthquake-Induced Cracks on Benches

  9. Pre-Design Scope of Work Review / Synthesize Available Information Field Investigation Laboratory Test Program Limit Equilibrium Stability Analysis Seismic Hazard Analysis Seismic Response and Deformation Analysis Static Deformation Analysis Toe Buttress Investigation Findings / Recommendations for Closure Design

  10. Review / Synthesis of Available Information Bottom Contours of Quarry East End Interim Cover Southwest Corner Liquid Co-Disposal Toe Buttress Construction Inclinometer Data Previous Geotechnical Studies Strong Motion Records 1992 Cover Failure

  11. MSW Properties: Shear Strength

  12. Field Investigation SASW Survey 3 x 34-inch (840-mm) Diameter Borings to 155 ft (47 m) • Waste Characterization • In Situ Unit Weight Tests • Video Logging 20-ft (6-m) Deep Test Trench Toe Buttress Condition Survey Cover Soil Investigation

  13. Field Exploration Plan

  14. Vibroseis for SASW Testing

  15. Sampling and Testing Intervals

  16. Large Diameter Bucket Auger Borings

  17. Field Classification Scheme

  18. Field Logging

  19. Waste Degradation

  20. Waste Temperature

  21. In Situ Unit Weight Testing 1. Auger and collect waste 2. Weigh waste 3. Place tremie pipe in borehole 4. Fill with gravel of known unit weight

  22. In Situ Unit Weight Results

  23. Downhole Video Logging

  24. Downhole Video Logging

  25. Downhole Video Logging

  26. On-Site Laboratory Reconstituted 18-inch (454-mm) Diameter Specimens Consolidometer, Direct Shear, Cyclic Simple Shear Less than1 yr for Design and Fabrication

  27. Cyclic Simple Shear Device

  28. Lab Sample Characterization Bulk Sample Sorted Sample

  29. Consolidation Test Results

  30. Direct Shear Results

  31. Cyclic Simple Shear Tests

  32. Cyclic Simple Shear Test Results

  33. Strong Motion Instrumentation

  34. Quad-4M Seismic Response Model

  35. Wastecon 2004 Back Analysis of Seismic Response

  36. MSW Modulus Reduction and Damping

  37. Limit Equilibrium Analysis Static Analysis • Horizontal Planes of Weakness • Perched Water Levels • Cover Veneer Failures Pseudo-Static Analysis • Yield Acceleration

  38. Cover Veneer Stability

  39. Seismic Response Analysis

  40. Seismic Deformation Curves Typical range of waste mass seismic displacements

  41. Static Deformation Analysis 30-yr Performance of Final Cover • Drainage • Cracking 30-yr Performance of Toe Buttress • Static (followed by seismic)

  42. Vertical and Lateral Displacments

  43. Toe Buttress Analysis Global Stability • Limit Equilibrium FS = 2.6 Internal Stability • Finite Element Analysis (GeoFEAP) • Static: Imposed Deformations • Pseudo-Static: Seismic Coefficient

  44. Toe Buttress Displacements Measured Projected

  45. Toe Buttress Performance Analysis

  46. Toe Buttress Analysis Results

  47. Findings / Recommendations • The Waste Mass Meets Stability Criteria • Static and Seismic • Large Static Deformations are Expected • Continuous Maintenance • Toe Buttress Should Maintain Its Integrity • Long Term Settlement plus Seismic Loading • Cover Stability is a Major Concern • Particularly the Steep North Slope

  48. LESSONS LEARNED • MSW is Pretty Strong Stuff • Stronger than Often Assumed in Practice • MSW can be Pretty Heavy • Unit Weight Greater than Typically Assumed • Unit Weight can be Very High if Saturated • MSW Cyclic Degradation is Slow • Potential for Significant Seismic Amplification • MSW is Anisotropic • Preferred Horizontal Orientation • MSW Deformation is Non-Homogeneous

  49. CONTRIBUTIONS TO PRACTICE • In Situ Unit Weight Test Method • Field Classification System for Waste • Data on Waste Composition • MSW Shear Strength Envelope • Compositional Effects on Strength, Compressibility • MSW Shear Wave Velocity Measurements • MSW Modulus Reduction and Damping

  50. Acknowledgements

More Related