FHWA-NHI-132XXX Introduction to Rock Slope Stabilization Measures

1. FHWA-NHI-132XXXIntroduction to Rock Slope Stabilization Measures The presentation is available as an attachment from the paperclip icon in the bottom right-hand part of the screen.

2. Module Introduction This module contains 4 lessons: • Lesson 1: Overview • Lesson 2: Scaling • Lesson 3: Rock Bolting • Lesson 4: Shotcrete During each lesson, we will provide knowledge checks, which you may wish to take in order to test your understanding of the material presented in the lesson. The knowledge check is optional.

3. Training Purpose • The purpose of this web training is to familiarize the construction inspector with current techniques utilized to stabilize rock slopes with respect from rock fall. • The training consists of photos and videos from highway projects throughout the United States. Captions, callouts, and highlights are used to emphasize important points.

4. Learning Objectives Upon completion of this module, you will be able to: • Learning Outcome • Learning Outcome • Learning Outcome • Learning Outcome

5. Lesson 1: Overview By the end of this lesson, you will be able to: • Identify Rockfall Treatment Measures • Describe Scaling/Removal Techniques • Explain Reinforcement

6. Gravity Works! Rock fall occurs on many highways around the world.

7. Gravity Works!

8. Scaling How is this rock still here?

9. Scaled Rock Rock waste is usually a significant project item

10. Rockfall Treatment Measures The Rockfall Problem - A single rock falling above a roadway can have disastrous consequences. • Avoidance/Protection • Stabilization Measures

11. RockfallTreatment Measures Avoidance/Protection • Fallout areas • Draped Mesh • Rockfall Barriers

12. Rockfall Treatment Measures Stabilization Measures • Slope Geometry Alteration -Scaling • Reinforcement -Rock Bolts • External Stabilization -Shotcrete

13. Rockfall Treatment Measures Stabilization Measures • Engineered slopes require stabilization • long-term viability • reduce slope failure • Prevent the failure at the source through stabilization • altering the slope geometry • installing drainage • adding reinforcement • using combinations of these methods

14. Stabilization Measures Reinforcement: Rock Bolting Slope Geometry Alteration: Scaling Not sure where this goes External Stabilization: Shotcreting

15. Scaling/Removal Techniques • Hand Scaling - Removal of loose rock from slope by means of hand tools. • Mechanical Scaling - Removal of loose rock from slope by mechanical equipment. • Blast Scaling - Removal of loose rock or large rock blocks from slope by means of blasting or chemical expanders. • Trim Blasting - Removal of overhanging faces or protruding knobs that may act as launch features on a slope. • Re-sloping - Cutting the rock slope at a flatter angle to improve slope stability and rockfall trajectories (Lay the slope back).

16. Scaling/Removal Techniques Slope Geometry Alteration • Change the configuration of a slope • Remove potential falling rock (fly rock) • Remove slope features that might launch falling rock outwards.

17. Scaling/Removal Techniques • Slope Geometry Alteration • Hand Scaling

18. Reinforcement • Rock Bolts - Tensioned steel bars used to increase the normal-force friction and shear resistance along potential rock-block failure surfaces. • Dowels - Untensioned steel bars used to increase shear resistance. Increases normal-force friction once block movement occurs. • Shear Pins - Provides shear support at the leading edge of a dipping rock block or slab using grouted steel bars. • Shotcrete - Pneumatically applied concrete primarily used to halt erosion but can also retain small rock blocks and provide structural support.

19. Knowledge Check (multiple choice, multiple answers)Select all answers that apply. a) Correct 1 b) Incorrect 1 c) Correct 2 d) Incorrect 2 You have provided an incomplete answer. Select anywhere to try again. Incorrect. You did not answer this question completely. You answered this correctly. Incorrect. Advance to the next slide for a debrief. Select anywhere to continue. Correct. Advance to the next slide for a debrief. Select anywhere to continue. Incorrect. Select anywhere to try again. Submit Clear The correct answer is:

20. Lesson 1: Summary In this lesson, you have learned how to: • Identify Rockfall Treatment Measures • Describe Scaling/Removal Techniques • Explain Reinforcement This concludes Lesson 1: Overview.

21. Lesson 2: Scaling By the end of this lesson, you will be able to: • Describe Blast Scaling • Identify Mechanical Scaling • Identify Cable Scaling • Explain Hand Scaling • Describe Other Scaling Tools – Hydraulic Jack • Explain Scaling from Lifts and Video

22. Scaling • Removal of loose rock from slope by means of hand tools and/or mechanical equipment. Commonly used with other design elements.

23. Scaling • Blast Scaling • Mechanical Scaling • Cable Scaling • Hand Scaling • Other Scaling Tools – Hydraulic Jack • Scaling from Lifts and Video Six interaction slides

24. Scaling Blast scaling (video) Note: The crane supported blasting mat to protect the roadway

25. Scaling Blast Scaling

26. Scaling Blast Scaling Blast Scaling (Crack) – This method produces a big bang!

27. Scaling Blast Scaling Blast Scaling – In this case explosives are placed in rock fractures (Crack Scaling). It is difficult to control blast scaling.

28. Scaling Crack Scaling Before After Mild change or improvement can be seen here.

29. Scaling Mechanical Scaling Video Note: Mechanical scaling requires a careful approach to control removal

30. Scaling Mechanical scaling - Using a long reachhoe ram.

31. Scaling Cable Scaling Video

32. Scaling Cable Scaling

33. Scaling Hand scaling Video

34. Scaling Hand scaling

35. Scaling Significant Blast and Hand Scaling are needed

36. Scaling Other Scaling Tools • Hydraulic Jack

37. Scaling Hand hydraulic jack being used for scaling

38. Scaling Scaling from lifts Video

39. Scaling Scaling from telescoping boom lifts can be very productive.

40. Scaling Typical scaling bar

41. Scaling Typically, a slightly different scaling bar is used when working from a lift.

42. Scaling Hydro-Scaling • This approach can remove loose material in difficult to reach locations but it has limitations due to sediment run-off.

43. Knowledge Check (multiple choice, multiple answers)Select all answers that apply. a) Correct 1 b) Incorrect 1 c) Correct 2 d) Incorrect 2 You have provided an incomplete answer. Select anywhere to try again. Incorrect. You did not answer this question completely. You answered this correctly. Incorrect. Advance to the next slide for a debrief. Select anywhere to continue. Correct. Advance to the next slide for a debrief. Select anywhere to continue. Incorrect. Select anywhere to try again. Submit Clear The correct answer is:

44. Lesson 2 Summary In this lesson, you have learned how to: • Describe Blast Scaling • Mechanical Scaling • Cable Scaling • Hand Scaling • Other Scaling Tools – Hydraulic Jack • Scaling from Lifts and Video This concludes Lesson 2: Scaling.

45. Lesson 3: Rock Bolting By the end of this lesson, you will be able to: • Describe Rock Bolt Drilling • Explain Rocking Bolt Drilling Steps • Identify Rock Bolt Site Examples – NEED SOME HELP HERE • Identify Rock Bolt Drilling Tools and Equipment • Explain Grouting

46. Rock Bolting • Tensioned steel bars used to increase the normal-force friction and shear resistance along potential rock-block failure surfaces.

47. Rock Bolting Rock Bolt Drilling Steps Video

48. Rock Bolting Rock Bolt Drilling Steps • Inserting resin cartridges Video

49. Rock Bolting Rock Bolt Installation

50. Rock Bolting Rock Bolt Drilling Steps • Inserting rock bolt Video