FIELD

[0001] The present invention relates to barrier system which includes a composite rail particularly but not exclusively for spanning between supports such as abutments of a bridge or culvert.

BACKGROUND

[0002] Bridge barriers are designed to protect motorists from vaulting off the bridge and into surrounding or underlying hazards. These barriers typically need to be very rigid to retain the errant vehicle within the traffic lane and to prevent it from encroaching into the unsupported void beyond the edge of the bridge deck.

[0003] A problem exists on relatively small span bridges typically less than 20 metres between abutments where a large percentage of bridge decks commonly made from timber or thin concrete decks possess insufficient structural capacity to withstand the imposed loads from support posts of barrier systems in the event that the barrier system is impacted by an errant vehicle.

[0004] The structural inadequacy of the bridge deck results in compromise to the safe performance of the barrier system as well as being a significant maintenance liability due to costs incurred to repair the damaged bridge deck and/or support structure.

[0005] There are approximately 30,000 timber bridges across Australia. A majority of these bridges do not have an Australian Standard compliant barrier system. Bespoke designed bridge barriers spanning the full length of the bridge have been used to avoid the need for posts installed on fragile bridge decks. These barriers have typically being designed using large steel structural sections. The geometry of these structural sections do not provide good continuity with the approaching roadside safety barriers and they are also limited in the maximum achievable span to approximately 12 lineal metres.

[0006] The present invention seeks to provide an improved barrier system that is able to span the full length of a bridge, culvert or stretch of ground adjacent a void without the need for supporting posts between the two bridge abutments. SUMMARY

[0007] In accordance with the invention, there is provided a barrier system for a road which bridges a void including a support either side of the void and a rail fastened to the supports to contain an errant vehicle driving off the road and into the void, wherein the rail has a composite structure that includes an external skin and a substantially non- compressible core material extending lengthwise of the rail.

[0008] In one embodiment, the core material is formed from a settable material. [0009] In one embodiment, the core material is concrete. [0010] In one embodiment, the skin is steel.

[0011] In one embodiment, the skin includes side walls and top and bottom covers to close the rail.

[0012] In one embodiment, the covers include clips to attach to the side walls.

[0013] In one embodiment, the rail includes a cavity that extends lengthwise of the rail, which acts as a crumple zone.

[0014] In one embodiment, the cavity extends along a top of the rail.

[0015] In another embodiment, the cavity extends along a bottom of the rail.

[0016] In one embodiment, the rail includes a coupling that connects the rail to one of the supports, the coupling including a substantially horizontal connection plate that rests on a bracket of the support.

[0017] In one embodiment, the supports are in the form of square posts that act as abutments either side of the void and the brackets are welded to the posts.

[0018] In one embodiment, the plate is embedded in the core and has an aperture through which the material of the core is poured and set in order to anchor the plate in the rail. [0019] In one embodiment, the rail includes an extension section which connects to a roadside barrier of the barrier system, the extension section having holes to receive fasteners that fix the road-side barrier to the rail.

[0020] In one embodiment, the rail includes an extension section at both ends.

[0021] In one embodiment, the rail is in the order of between 6 and 24 metres in length.

[0022] In one embodiment, the barrier system includes foundation structure and a series of posts in the foundation structure to support the roadside barrier.

[0023] In one embodiment, the rail is formed of modules connected by attachment plates.

[0024] In one embodiment, the barrier system further includes a top rail system fixed above the rail, wherein the top rail system has a horizontal beam supported by a series of uprights along a length of the beam.

[0025] In one embodiment, each upright is fixed to the rail by a foot which is anchored to the rail by bolts.

[0026] In one embodiment, the bolts are cast into the core material of the rail.

[0027] In one embodiment, the bolts are fixed into the ferrules which are cast into the core material of the rail.

[0028] In one embodiment, the uprights are secured to the rail by expansion anchor bolts or anchor screws drilled and mechanically secured in place or chemical anchor bolts can be set into the core material for the addition of the top rail assembly.

[0029] In another aspect, there is provided a rail for use in the above barrier system with a composite structure that includes an external skin and a substantially non- compressible core extending lengthwise of the rail.

[0030] In another aspect, there is provided a rail with a coupling that connects the rail to a support, the coupling including a substantially horizontal connection plate embedded in the rail, the connection plate having an aperture through which material of the core is poured and set in order to anchor the plate in the rail.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The invention is described by way of non-limiting example only with reference to the accompanying drawings, of which:

[0032] Figure 1 shows the elevation view of an assembly of the bridge barrier system including the approach and departure roadside barrier;

[0033] Figure 2 shows the plan view of the system;

[0034] Figure 3 shows an isometric view of an assembly of the bridge barrier system;

[0035] Figure 4 shows the abutment post that supports the bridge barrier system;

[0036] Figure 5 shows the connection detail at the abutment post;

[0037] Figure 6 shows a plan view of the connection detail at the abutment post that supports the barrier system;

[0038] Figure 7 shows a cut section view of the bridge barrier system showing the outer steel encasement of the concrete fill;

[0039] Figure 8 shows a cut section of a rail of the bridge barrier system with the outer steel encasement of a partially concrete filled beam to provide a crushable upper part of the beam;

[0040] Figure 9 shows a cut section of a rail of the bridge barrier with the outer steel encasement of a partially concrete filled beam to provide a crushable lower part of the rail;

[0041] Figure 10 shows a cut section of the bridge barrier rail with the outer steel encasement of a partially concrete filled beam to provide a crushable upper and lower part of the beam;

[0042] Figures 1 la to l id illustrate collision of a vehicle with the barrier system; [0043] Figures 12a to 12c are perspective views of a vehicle colliding with the barrier system.

[0044] Figure 13 is a perspective view of the barrier system with a modular rail; [0045] Figure 14 is a perspective end view of one of the rail modules; [0046] Figure 15 shows two rail modules connected together; and [0047] Figure 16 is a cross-sectional view of a rail with a top rail system. DETAILED DESCRIPTION OF THE INVENTION

[0048] Figures 1 to 3 shows a barrier system 1 that includes a series of posts 2 embedded in foundation structure 3 either side of a void 4.

[0049] The posts 2 support road-side barriers 5. Each barrier 5 has a first, second and third section 6, 7, 8. The first section 6 is in the form of a conventional W-profile barrier, the second section 7 transitions into a triple ridge barrier. The third section 8 is coupled to a rail 10 that spans the void 4.

[0050] The rail 10 is connected to the barriers 5 by an extension section 11 at either end 12. Couplings 13 are provided to mount the rail 10 to supports 14 that act as abutments either side the void 4. The supports 14 are shown as square posts 15 but other post configurations can be used, as required.

[0051] Figure 4 shows the couplings 13 as substantially horizontal plates 16 that rest on brackets 17 that are welded to the supports 14.

[0052] Fasteners 18 extend through the extension section 11 to connect the rail 10 to the roadside barriers 5 of Figures 1 to 3.

[0053] The rail 10 is a composite structure including an external skin 20, which is preferably formed of steel, and an internal core 21. The skin 20 includes side walls 22 and top and bottom covers 23, 24 that close the rail 10. The covers 23, 24 have clips 25 that attach to the walls 22. The skin 20 may be formed of any other suitable material, such as plastics or the like. [0054] The rail 10 has a triple ridge profile to match the profile of the third sections 8 of the barriers 5 but can be formed with more or less ridges, as required.

[0055] Figure 5 shows the extension section 11 connected to the roadside barrier 5 by the fasteners 18 which are in the form of splice bolts 26.

[0056] The plates 16 of the couplings 13 are shown resting on the brackets 17 and are secured in place by bolts 27. The horizontal configuration of the brackets 17 and plates 16 allows the rail 10 to be self-supported on the brackets 17 before being fixed by the vertical bolts 26 so there is no requirement to separately hold the rail 10 in place while fitting the bolts 26, as would be the case if the rail was attached to the supports by horizontal bolts.

[0057] Figure 6 shows one of the couplings 13 as having an aperture 28. The aperture 28 is formed in one end 29 of the plate 16 which is embedded in the core 21. The core 21 is preferably formed of pourable material such as concrete which sets around the coupling 13 and within the aperture 28 to anchor the coupling 13 in the rail 10.

[0058] The bolts 26 are located on opposite sides of the post 15 and extend vertically so as to present maximum resistance to bending moments exerted on the rail 10 such as during a vehicle impact.

[0059] Figure 7 shows the rail 10 filled with concrete material. The concrete provides a non-compressible medium which is substantially rigid and has sufficient self-supporting strength to span up to 20 metres.

[0060] The skin 20 contains any material that might break or fracture from the core 21 as a result of impact of a vehicle.

[0061] Figure 8 shows a cavity 30 at a top 31 of the rail 10. The cavity 30 is formed by pouring concrete into the skin 20 and only partially filling the skin 20 so that the cavity

30 which extends lengthwise along the top 31 of the rail 10. The cavity 30 allows the top

31 of the rail 10 to function as a crumple zone.

[0062] Figure 9 illustrates a rail 10 that is formed in a similar manner but which is inverted to have the cavity 30 at a bottom 32 of the rail 10, to provide a lower crumple zone. [0063] Figure 10 shows another rail 10 where the core 21 extends only along a central region 33 of the rail 10 so that the top 31 and bottom 32 of the rail 10 can both act as crumple zones.

[0064] Figures 11a to l id illustrate an errant vehicle 34 on a deck 35 of a bridge 36 colliding with the rail 10. The vehicle 34 is on a collision course in Figure 11a, impacts with the rail 10 in Figure l ib and is redirected back onto the road 37 in Figures 11c and l id.

[0065] Figures 12a to 12c are perspective views showing the same collision and redirection sequence of Figures 11a to l id, demonstrating how the rail 10 is effective in containing the vehicle 34 and preventing the vehicle 34 driving off the road 37 and into the void 4.

[0066] As may be appreciated from the above, the rail 10 is preferably a composite external steel encasement or external steel sandwich encapsulating a concrete core 21 that provides an efficient structure to support its self-weight and span a length over a bridge, culvert or serviced ground of anywhere in the order of 6 and 24 lineal metres and preferably up to 20 lineal metres. The external steel facade of the rail 10 provides continuity with conventional roadside barriers 5.

[0067] The composite design provides a structural section that has required high torsional strength to prevent twisting of the barrier system 1 that would otherwise permit vehicle roll causing instability in redirecting the errant vehicle. Moreover the rail 10 is ideally suited to providing a safety barrier on a deck of a bridge 36. The rail 10 provides a very structurally efficient section that is narrow thereby requiring minimal encroachment into the available traffic lane space on the bridge. The high bending strength of the composite section also minimises deflection of the rail 10 preventing the vehicle 34 from encroaching into the void 4 beyond the bridge deck 35.

[0068] The external steel encasement ensures any fractured concrete elements are contained and prevented from becoming a potential hazard to anyone moving below the bridge.

[0069] As mentioned above, the rail 10 may be partially filled with concrete to provide a relatively weaker zone or crumple zone along the bottom 32 of the rail 10 for the purpose of permitting this bottom area to more readily crush on impact thereby causing less damage to the vehicle's wheels and steering system to provide a safer redirection of the vehicle.

[0070] Similarly the rail 10 may be partially filled with concrete to provide a relatively weaker zone or crumple zone along the top 31 of the rail 10 for the purpose of permitting this top area to more readily crush on impact thereby causing less damage to the vehicle in the head impact zone of the motorist. The rail 10 may also be partially filled with concrete along the length of the barrier so as to strengthen the structural section of the barrier through the centre region of its span where the bending moment or forces acting on the barrier are at their highest.

[0071] Figure 13 shows a barrier system 50 similar to the system 1 described above and like reference numerals are used to denote like parts.

[0072] The system 50 has a modular rail 51 including two end modules 52 and a center module 53. The rail 51 may instead be formed of a greater or lesser number of modules, as required.

[0073] The end modules 52 are connected to the road-side barriers 5 in a similar manner to the rail 10 described with reference to Figures 1 to 12. The module 53 is joined to each of the end modules 52 using attachment plates 54, which are bolted to each of the respective modules 52, 53.

[0074] Figure 14 shows an end 55 of one of the modules 52 with bolt holes 56 in both side walls 22.

[0075] Figure 15 illustrates an attachment plate 54 fixed to each of the modules 52, 53 by bolts 57 in order to connect the modules 52, 53 together. An attachment plate 54 is fixed on both sides of the rail 50 to provide structural rigidity.

[0076] As may be appreciated, the modules 52, 53 are of shorter length than the overall rail 50 and can be more easily transported to an on-site location for assembly particularly if the rail 50 is of a length greater than, say, 10 lineal metres which might otherwise present difficulties for a transport vehicle in negotiating turns or bends in a roadway. [0077] Referring now to Figure 16, the barrier system 1 is provided with a top rail assembly 60 which can be added to the rail 10 for containment of heavy vehicles such as trucks.

[0078] The top rail assembly 60 includes a horizontal beam 65 supported by a series of uprights 61, only one of which is shown, along a length of the rail 10. The upright 61 is fixed to the rail 10 by a foot 62 which is secured onto anchor bolts 63 by nuts 64. The bolts 63 may be cast into the rail 10 by being set in the pourable material of the core 21. Alternatively, ferrules (not shown) could be cast into the core 21 for bolts to screw into.

[0079] As a further alternative, the uprights 61 can be secured to the rail 1 by expansion anchor bolts or anchor screws can be drilled and mechanically secured or chemical anchor bolts can be set into the core material for the addition of the top rail assembly 60.

[0080] The top rail assembly 60 can be used with either the rail 10 or the modular rail 50 described with reference to Figures 13 to 15.

[0081] Many modifications will be apparent to those skilled in the art without departing from the scope of the present invention.