1. STRUT STABILIZATION PART 1

2. ‘Vehicle & Machinery Rescue’ Stabilization
Explain course is built around two NFPA Standards; 1006 (Chapter 10) and 1670 (Chapter 8 & 12)
Course materials also include information from University of Extrication series, as originally published in Firehouse Magazine
Course materials also include information from Vehicle Rescue book, Moore
Course materials also include information from IFSTA Essentials of Firefighting

3. Cribbing 2 x 4 wood 4 x 4 wood 6 x 6 wood Wedges 4 x 4 x 8’ Stepchocks
Double Box Crib: 24,000 lbs. rating
2 x 4 wood
4 x 4 wood
6 x 6 wood
Wedges
4 x 4 x 8’
Stepchocks
Cribbing provided by TCC includes;
2 x 4 wood
4 x 4 wood
6 x 6 wood
Wedges
4 x 4 x 8’
Stepchocks

4. Triple Box Crib Solid Bottom Layer 4” overlay @ ends
55,000 lbs. rating
Interactive discussion of cribbing building and rating of cribbing
Triple Box Crib with Solid Bottom Layer and 4” ends yields 55,000 lbs. rating

5. Reason for overlap at ends of box crib
Crush testing of various types of wood in a 55 ton press unit
Note failure of cribbing and ‘flaring’ of ends
Explain that overlap at ends of a box crib is to allow end flaring to lock cribbing into place under heavy load

6. Cribbing Safety
Height of Box Crib should not exceed 2x the working width of the base of the box crib
18” cribbing = 36” box crib height
Height of Box Crib should not exceed 2 times the working width of the base of the box crib
18” cribbing = 36” box crib height

7. Cribbing wedges should have a square base and to provide maximum strength to wedge
Cribbing wedges should have a square base end to provide maximum strength to wedge 7

8. Stabilization with Strut Systems
Conduct interactive discussion of possible or anticipated challenges faced by rescue personnel at case study incident shown
Stabilization with Strut Systems

9. Conduct interactive discussion of possible or anticipated challenges faced by rescue personnel at case study incident shown

10. Strut System Deployment
Deployment of typical ‘strut’ system; 4-strut stabilization shown

11. Light-Duty Struts Typically rated capacity of 4,000#
Tensioned Buttress Stabilization Systems...commonly referred to as “Struts
Industry Standard 20’ Ratchet Strap with Wire Hooks systems that generally are used with struts for tensioning at typically rated at 3 to 1 Safety Factor
3,300# Working Limit Load

12. “CAM Buckles” attached to base of strut only have a Working Load Limit of 700#
Tensioned Buttress Stabilization Systems...commonly referred to as “Struts
Industry Standard 20’ Ratchet Strap with Wire Hooks systems that generally are used with struts for tensioning at typically rated at 3 to 1 Safety Factor
3,300# Working Limit Load

13. Detachable 20’ Ratchet Strap with Wire Hooks
3 to 1
Safety Factor
Working Load
Limit of 3,300#
Tensioned Buttress Stabilization Systems...commonly referred to as “Struts
Industry Standard 20’ Ratchet Strap with Wire Hooks systems that generally are used with struts for tensioning at typically rated at 3 to 1 Safety Factor
3,300# Working Limit Load

14. (Black with Orange Hooks)
Strut System Chain Kit
16‘ 7,100# WLL rating
(Black with Orange Hooks)
Chain Clusters-
5,400# WLL rating
Grade 70 “mini T”, “mini J”
& chain shortener
Strut System Chain Kits typically include’
16‘ 7,100# WLL rating
(Black with Orange Hooks)
Chain Clusters-
5,400# WLL rating
Grade 70 “mini T”, “mini J”
& chain shortener

15. Opposing triangles on roof side
Compression
Tension
Creating of ‘triangles’ and tensioning of struts places the strut under compression and the strap system under tension
Opposing struts form opposing triangles to support and stabilize load
Opposing triangles on roof side

16. Set struts at 50o to 70o angle
Basic “2 Strut” Setup
Set struts at 50o to 70o angle
Typical strut manufacturer recommends strut placement angle of 50 – 70 degrees; a ground ladder climbing angle

17. Stabilization Full “4 Strut” Setup X
Side-resting automobile can be stabilized with a 2-strut, 3- strut, or 4-strut deployment

18. Side-resting automobile stabilized with a 4-strut deployment
Stabilization X
Side-resting automobile stabilized with a 4-strut deployment
Side-resting automobile stabilized with a 4-strut deployment

19. “Trapezoid” Deployment: Roof-Resting
Trapezoid deployment of struts for a roof-resting vehicle stabilization

20. “Trapezoid” Deployment for Stability
Trapezoid deployment creates triangles for most effective vehicle stabilization

21. Improvised Struts
‘Homemade’ street sign post used to build struts shown deployed in Real World incident

22. Improvised Struts
Improvised ‘strut’ for stabilization

23. Struts for Vehicle Stabilization
Paratech “Green”
Struts for Vehicle Stabilization
One method of stabilizing a large vehicle with struts and straps using wheel, tire, and wheelwell area

24. Green Struts
WL = 10,000#
One method of stabilizing a large vehicle with struts and straps using wheel, tire, and wheelwell area

25. Paratech” “Grey” Struts For Stabilization of Heavier Loads
One method of stabilizing a large vehicle with struts and straps using wheel, tire, and wheelwell area