Anchors rock anchors

Anchors rock anchors

1. 002 ROCK ANCHORS http://www.cpi-team.com

2. Science Art Religion Politics Scholarly Articles For Mathematics and Productivity http://www.twitlonger.com/show/n_1sp9pjo?new_post=true  … Dr f Dejahang BSc CEng, BSc (Hons) Construction Mgmt, MSc, PhD 

3. ROCK ANCHORS

4. http://www.youtube.com/watch?v=8qUuQbi4ocQ http://www.youtube.com/watch?v=eICMSgr-x14&feature=related ROCK ANCHORS

5. Corrosion Protection and Anchor Longevity

6. ROCK ANCHORS

7. Rock Anchor Components (PCI, 1974). (Note the lack of protection to the steel other than grout.)

8. ROCK ANCHORS

9. ROCK ANCHORS

10. ROCK ANCHORS The details are summarized in Table 1 and a “decision tree” (Figure 2) was provided for the guidance of designers.

11. Table 1. Corrosion Protection Requirements (PTI, 1996).

12. Figure 2. Corrosion Protection Decision Tree (PTI, 1996).

13. ROCK ANCHORS 2004 The existing Recommendations were revalidated while it is stated that, for permanent anchors, “aggressive conditions shall be assumed if the aggressively of the ground has not been quantified by testing.”

14. ROCK ANCHORS Table 1 was revised, as shown in Table 1R, mainly to clarify the Class I status of epoxy protected steel in a “water proofed hole.” The sophistication of contemporary tendons is shown in Figure 3 and 4. A long supplement is devoted to epoxy protected strand.

15. Table 1R. Corrosion Protection Requirements (PTI, 2004).

16. Figure 3. Class I Protection – Encapsulated Strand Anchor (PTI, 2004). Figure 4.

17. Figure 4. Class I Protection – Epoxy Coated Strand Anchor (PTI, 2004).

18. ROCK ANCHORS Between 1974 and 2006 Extremely sophisticated corrosion protection systems were developed and (ii) the latitude offered to designers relative to choice of corrosion protection intensity and details was severely restricted: to install a permanent anchor in a dam without Class I protection is now not only impermissible, but unthinkable.

19. Full Length (Corrugated and Smooth) Encapsulation (Franklin Falls Dam, NH, 1980)

20. Full Length Corrugated Protection (Dolby Dam, ME, 1995).

21. ROCK ANCHORS Permanent Anchors Permanent anchors come in many different shapes, sizes and types. (supply of all materials, fabrication, installation, grouting, testing, tensioning, lift-off testing). 

22. Permanent Anchors

23. Tested system for multi-strand permanent anchor

24. ROCK ANCHORS Multi-strand system ranges from a single strand of working load 150 kN to 27-strands that accommodate over 4000 kN (400 ton force +) of tension capacity.  With typical permanent anchors double-encapsulated and sheathed in sinusoidal HDPE, design lives can stretch to 100 years.

25. ROCK ANCHORS

26. Permanent Stressbar Anchors Permanent Stressbar Anchors are high-strength, 1000 MPa grade threaded bar, used mainly in Civil & Infrastructure retention and construction works. As with the multi-strand anchors, the stressbar is encapsulated in a sinusoidal sheathing providing a design life of up to 100 years.  Standard thread bar sizes allow for a safe working load of up to 660 kN , but non-standard sizes allow for a far greater load.  

27. ROCK ANCHORS

28. Permanent Rock Bolts Similar to permanent stressbar anchors, rock bolts are a lesser grade – 500 MPa – of threaded and are more common.  Ranging in size from 20 to 40mm in diameter, rock bolts are most commonly found in Infrastructure retention systems and can be both actively or passively (nominally) tensioned, usually against, or encapsulated-in, shotcrete walls.

29. ROCK ANCHORS

30. 12 tonne Excavation Drill Rig

31. ROCK ANCHORS Unbonded Length Bond Length

32. Typical Uses:  Temporary Applications with a service life of <= 24 Month Wedge Wedge Plate Bearing Plate Greased & PE or PP Extruded Strand in Unbonded Length Spacers along Bond Length Bare Strand in Bond Length Centralizer

33. Anchor with Double Corrosion Protection (PTI-Class I)

34. ROCK ANCHORS Grout Filled Bond Length Encapsulated Greased & PE Extruded Unbonded Length Cover Cap Wedge Wedge Plate Bearing Plate Trumpet Greased & PE or PP Extruded Strand in Unbonded Length Corrugated Sheathing Spacers along Bond Length Bare Strand in Bond Length Centralizer End Cap