1. ROCKFALL BARRIER

2. FALLING VELOCITY A=Broken barrier A = Sacrificial Barrier B = Effective barrier Higher velocities (i.e. 35-40 m/s) are assumed to make one barrier collapse under the impact . In such case multiple barrier lines shall be used: the first sacrificial line will break dissipating the block, the second barrier will stop it. Barriers are certified for velocities up to 30 m/s.

3. FALLING ENERGY E nergy of a falling rock: E = E  + E k E k = translational energy = ½ M v 2 M = block mass v = translational velocity E  = rotational energy = ½ I  2 I = inertia moment  = angular rotational velocity The most effective energy is the translational one which is normally 80% (or higher) than the total kinetic energy. The rotational energy is around 10-20% of the total energy and is related to the shape of the block.

4. FALLING ENERGY E = potential energy m = mass g = gravity 9.81 m/s 2 h = falling height h E  1/ 3 m g h

7. HOW TO ANALYSE THE FALLING OF THE ROCKS - Site observations; - Numerical modeling ; THE SITE OBSERVATIONS NORMALLY GIVE THE POSSIBILITY TO APPRECCIATE THE EFFECTS OF THE FALLING OF THE ROCKS. NUMERICAL MODELLING CAN DESCRIBE THE FALLING TRACKS, SUGGESTING THE KNOWLEDGE OF THE PARAMETERS TO BE USED DURING THE FINAL DESIGN OF THE PROTECTION.

9. NUMERICAL MODELLING RESULTS ( IN 2 DIMENSIONS ) The most relevant results obtained from the numerical model are: Topographic section with the rock trajectory

10. Topographic section with the end point of the trajectory

11. Topographic section with the trajectory related to the maximum falling heights

12. Topographic section showing the maximum falling energies

15. F  t = M  v The capacity of a “non deformable” barrier is related to the elastic deformability of its components. Because its components are stiff (cable, post), the “non deformable” barriers must slow down the velocity (  v) in a very short time (  t). The force F of impact F = M  v /  t is very high. Then the non deformable barrier break at very low energy level. The limits of non deformable barriers

16. Rockfall barriers New barrier series according to ETAG 27 GUIDELINE FOR EUROPEAN TECHNICAL APPROVAL of FALLING ROCK PROTECTION KITS - Draft - Edition November 2006 OM CTR barriers satisfy a wide range of energy levels ETAG 27 and performances Energy level Velocity Boulder Volume Name of Barrier 500 kJ 25 m/s 0.6 m 3 CTR 05/07/B 1 000 kJ 25 m/s 1.2 m 3 CTR 10/04/B 2 000 kJ 25 m/s 2.4 m 3 CTR 20/04/A (ring panel) 2 000 kJ 25 m/s 2.4 m 3 CTR 20/04/B (cable panel) 3 000 kJ 25 m/s 3.5 m 3 CTR 30/04/B 5 000 kJ 25 m/s 5.8 m 3 OM CTR 50/07/A

17. ETAG 27 require 2 test: OM CTR barriers are certified both for MEL and SEL tests ETAG 27 and performances MEL = Maximum Energy Level The barrier has to catch a boulder with the maximum energy level. The residual height of the panel after the impact indicates the quality level of the barrier. SEL = Service Energy Level The barrier has to catch two impacts of a boulder with 1/3 of the MEL energy without damage. The residual height after the first impact must be greater than 70%. The second impact needs only to catch the boulder.

18. ETAG 27 and performances Lateral view of a falling rock protection kit OM CTR barriers do not need down slope cable

19. 0°    90°  -20°     +20° Nominal height of the barrier Residual height (after impact) OM CTR barriers give the best residual height ETAG 27 and performances  

20. OM CTR barriers give the best residual height ETAG 27 and performances Producer of 3000 kJ ISOFER AG GEBRUGG AG CTR Name of the barrier ISOSTOP 3000 kJ RXI 300 CTR 30/04/A Nominal Height 5.23 m 4.79 m 5.00 m Residual height after 100% Energy 49.14 % (5.23 m) 62.23 % (3.18 m) 66.00 % (3.30 m) Producer of 2000 kJ ISOFER AG GEBRUGG AG CTR CTR Name of the barrier ISOSTOP 2000 kJ RXI 2000 CTR 20/04/A CTR 20/04/B Nominal Height 4.80 m 5.11 m 4.00 m 5.00 m Residual height after 100% Energy 54.79 % (2.63 m) 62.23 % (3.18 m) 71.25 % (2.85 m) 73.00 % (3.65 m)

21. Falling rock protection kit classes A classification for residual height for MEL is also foreseen as follows: Category A : Residual Height ≥ 50 % nominal height Category B : 30% nominal height < Residual Height < 50 % nominal height Category C : Residual Height ≤ 30 % nominal height OM CTR barriers are classified in “A” category They are safer with respect to the height of impact. ETAG 27 and performances

22. ETAG 27 and performances OM CTR barriers gives the lowest elongation unload position Maximum elongation during the impact More flexibility when installing close to infrastructure   Net before impact

23. ETAG 27 and performances OM CTR barriers give the lowest elongation More flexibility when installing close to infrastructure PRODUCER OF 2000 kJ ISOFER AG GEBRUGG AG CTR CTR Name of the barrier ISOSTOP 2000 kJ RXI 2000 CTR 20/04/A CTR 20/04/B Max deformation with Max Energy Level (dynamic condition) no one indication no one indication 4.65 m 4.30 m Residual deformation after Max Energy Level (static condition) 6.80 m 6.70 m 4.20 m 4.05 m PRODUCER OF 3000 kJ ISOFER AG GEBRUGG AG CTR Name of the barrier ISOSTOP 3000 kJ RXI 300 CTR 30/04/A Max deformation with Max Energy Level (dynamic condition) no one indication no one indication 5.20 m Residual deformation after Max Energy Level (static condition) 7.40 m 6.60 m 4.60 m

24. Block size Energy FIELD TEST Vertical field test Inclined field test Falling velocity >= 25 m/s OM CTR barriers are tested on vertical field ETAG 27 and performances

25. ETAG 27 and performances The force shall be measured during the entire time of impact The field tests done by OM CTR measure the force acting on the stream cable and on the base plate. No other manufacturer measures shear and pressure forces acting on the base plate

26. The field test is conducted on a barrier with 3 modules in a straight line, that is why 3 modulus is the suggested minimum length of a barrier Configuration of the Crash test barrier ETAG 27 and performances Plan view Front view Lateral post Intermediate post Lateral post Intermediate post

27. 1000 KJ Barrier Test

28. ETAG 27 and performances

29. OM CTR barriers allow some tolerance when positioning the post: more flexibility when installing on rough slope. Easy to install R 15° (*) Plan view Front view (*) the value can be increased using lateral anchors or downslope anchor. 10.0 m 0.50 m

31. Easy to install Note: The correct design and on site positioning of barriers is typically site specific. Up slope down slope Up slope down slope Plan view The barrier works in a good way but could require some down slope anchors to stabilize the structure The barrier could work in a bad way but doesn’t require any devices to stabilize the structure

32. OM CTR barriers can be installed both on vertical and inclined slopes. Easy to install

33. Easy to install OM CTR barriers do not require downstream cables This allows faster and cheaper installation. Down slope Up slope

34. Easy to install OM CTR barriers are simple to install Taking into account the experiences on job sites, the assembling of the OM CTR barriers has been simplified by technical solutions. E.g. many connections are directly arranged in the factory.

35. OM CTR barriers are simple to install A number of field crash tests were performed which indicates the barrier has been designed and manufactured in the most economical and effective way (e.g. 15 for 500 kJ). No one component of the barrier is oversized (e.g. diameter of the cables). Many demanding jobs have been reduced (e.g. number of clamps) . Useless components have been removed (e.g. thimbles). Easy to install

36. Easy to install OM CTR barriers are fast and economical to install The standing up of the post is helped with a steel arm. The assembling of the posts by helicopter is faster. It requires one fifth of the time usually employed for other barriers.

37. Easy to install OM CTR barriers are more economical to install The forces measured on the base post are low. OM CTR barriers don’t require big plinths. The plinths are aimed to level and smooth the ground only.

38. Easy to install OM CTR barriers are easy to install Basically it is enough to use steel bars or miropiles for the foundations. Different base plates will be adopted. The plinth levels the ground. When ordering the barrier don’t forget to specify the kind of soils

39. Easy to install OM CTR barriers are fast to install OM CTR barriers has been created by people that assemble barriers in the field. The post can double up as ladder (*) (*) not for CTR 500 kJ where the posts are done by tubular elements

40. OM CTR barriers ensure high performances The friction brake is rasped by the rope running inside two steel plates. So the brake changes its behavior during the impact. In OM CTR barriers the brake system works by deformation and not by friction. This ensures the effectiveness of the system during the impact and in the most varying environmental situations (rust on cables, temperature, changes in the galvanization, etc.) Technology

41. Technology OM CTR barriers are easy to maintain The pin at the base of the post is designed as a fuse. It releases the post before the foundation can be destroyed. In this way the foundation is saved even if the boulder hardly hits the base of the post.

42. OM CTR barriers give high performances Technology Barrier CTR 20/04/A - 2006 June – Amelia - Italy Height of fall 70 m - Volume 4 m 3

43. OM CTR 2000 kJ, the best performances Technical comparison Producer ISOFER AG GEBRUGG AG CTR CTR OM Name of the barrier ISOSTOP 2000 kJ RXI 200 CTR 20/04/A CTR 20/04/B Certificated by UFAM/BAFU date 05/19/06 No. S 05 10 UFAM/BAFU date 05/19/06 No. S 04 7 DISTR University of Bologna DISTR University of Bologna Code for the test Swiss code Swiss code ETAG /Swiss ETAG / Swiss Kind of test Vertical field test Vertical field test Vertical field test Vertical field test Test velocity 25.00 m/s 25.00 m/s 25.78 m/s 25.35 m/s Number of test 1 - Small energy for piercing 1 - Small energy for piercing 1 - Small energy for piercing 1 - Small energy for piercing 2 - 50% energy (1000 kJ) 2 - 50% energy (1000 kJ) 2 - 100% energy (2250 kJ) 2 - 100% energy (2250 kJ) 3 - 100% energy (2000 kJ) 3 - 100% energy (2000kJ) 3 - 50% energy (1134 kJ) 3 - 100% energy (2250 kJ) 4 -1/3 energy (742 kJ) 5 -1/3 energy (742 kJ)

44. OM CTR 2000 kJ, the best performances Technical comparison Producer ISOFER AG GEBRUGG AG CTR CTR OM Name of the barrier ISOSTOP 2000 kJ RXI 2000 CTR 20/04/A CTR 20/04/B State of the structure after 100% energy Bending of a post, rupture of a base of a post, folding of a base plate Notes concerning the test Repairing works between 2nd and 3rd test Repairing works between 2nd and 3rd test No one repairing works No one repairing works Substitution of No. 14 brake systems Substitution of No. 13 brake systems no one no one Nominal Height 4.80 m 5.11 m 4.00 m 5.00 m Residual height after 100% Energy 54.79 % (2.63 m) 62.23 % (3.18 m) 71.25 % (2.85 m) 73.00 % (3.65 m) Maximum deformation with 100% energy no one indication no one indication 4.65 m 4.30 m Residual deformation after 100% energy 6.80 m 6.70 m 4.20 m 4.05 m Forces on foundation 117 kN max 235 kN max 260 kN lateral; 185 kN up slope 270 kN lateral; 220 kN up slope Notes on certificate RESERVATION: Should deficiencies arise following certification of the safety net, FOEN may revoke product release and delete it from the type approval list. RESERVATION: Should deficiencies arise following certification of the safety net, FOEN may revoke product release and delete it from the type approval list. No one reservation No one reservation