EP2108741A2

EP2108741A2 - Steel road safety barrier, for motorcycle accidents

Info

Publication number: EP2108741A2
Application number: EP08172101A
Authority: EP
Inventors: Vittorio Giavotto
Original assignee: PROVINCIA AUTONOMA DI BOLZANO
Current assignee: PROVINCIA AUTONOMA DI BOLZANO
Priority date: 2008-04-11
Filing date: 2008-12-18
Publication date: 2009-10-14
Also published as: ITMI20080642A1; EP2108741A3

Abstract

A road safety barrier (1) for motorcycle accidents is disclosed, comprising a plurality of uprights (101) that support a vehicle safety barrier (100) disposed at a certain height from the road surface (T), deformable spacers (3) made of shaped sheet steel, mounted on the uprights (101), and a plurality of segments of strip (2), made of shaped sheet steel, fixed to the spacers (3), so as to be disposed between the road surface (T) and the vehicle safety barrier (100) at a certain distance from the uprights (101).

Description

The present invention refers to a steel road safety barrier, for motorcycle accidents.
Widespread use is made of roadside safety barriers, commonly known as "guardrails", such as, for example, the safety barrier described in the European patent application EP 1 213 391 in the name of the same applicant. This type of safety barrier generally comprises a corrugated steel strip carried on spacers which are mounted projectingly on uprights or posts spaced out along the road. The corrugated steel strip is generally disposed at a height of about half a metre from the road surface. Therefore, the bottom part of the uprights is exposed up to a height of about half a metre.
Safety barriers are a valid means of containing vehicles or heavy vehicles swerving off the road, but they often do not guarantee the same performance for motorcyclists who come off the road following various types of accidents and even help to make the consequences of the accident more serious, causing severe injuries to the motorcyclist.
In fact, in the majority of motorcycle accidents occurs that the motorcyclist slides across the road surface after falling off the motorcycle and in these circumstances it is likely that the motorcyclist will hit any safety barriers present on the roadside, incurring serious and often fatal injuries. The most dangerous aspect is the impact of the motorcyclist against the posts of the barrier, which are generally metal sections with sharp edges. It must be considered that an accident at a motorcycle speed of more than 30 km/h is enough to cause amputation of a motorcyclist's limb that hits an upright of the safety barrier.
To overcome this drawback, various types of safety systems for motorcyclists are known to the art.
A safety system is known which provides for the insertion on existing safety barriers of a protective element of a soft material (polystyrene, polyurethane or similar materials) which covers the post, lessening the impact therewith. However, these protections present some drawbacks. In fact, although they are very simple to install, they are not very durable and usually have to be replaced every four years. Furthermore, the protection of the post by means of systems of this type loses its efficacy if the impact takes place at high speed and does not prevent the possibility that the motorcyclist may slip under the strip of the safety barrier or possibly exit the road surface.
To overcome these drawbacks at least in part, safety systems for motorcyclists are known to the art which provide for a second steel strip to be inserted in the bottom part of the safety barrier to prevent the motorcyclist from colliding with the post or from slipping beneath the strip adapted for containing vehicles. The new smooth strip does not have sharp edges or dangerous protrusions towards the outside, has a sufficient degree of containment (that necessary to contain a body going off the road) and does not impair the functioning of said safety barrier.
A similar system consists in using two polyethylene tubes which run beneath the main strip, suitably fixed to the supporting posts.
These systems, however, hold the drawback that the impact is lessened only by the running element (steel strip or plastic tubes), therefore this solution proves inadequate in the event of a head-on impact against the running element, especially at a supporting post.
Also known to the art are safety systems for motorcyclists consisting of modular elements of plastic material which, suitably connected to each other, surround the post and cover the part of the safety barrier beneath the main strip. Even if such a system ensures a greater lessening of the impact, thanks to the plastic element that surrounds the post, it presents some drawbacks due mainly to the use of plastic material which is of limited durability and of inadequate mechanical strength, especially in the event of the road having to be cleared of snow by means of a snowplough, which pushes the snow against the safety barrier. Furthermore, the assembly of these modular plastic elements proves excessively complex and costly.
It must be considered that the majority of motorcycle accidents occur on a bend and especially on the bends which do not have a constant radius of curvature. Motorcycle safety barriers according to the prior art are difficult to adapt to roads which have more or less accentuated bends. In fact they have discontinuous portions, with protruding edges, at the join between the various modules on the bend. These protruding edges prove to be very dangerous in the event of impact with a motorcyclist.
Object of the present invention is to overcome the drawbacks of the prior art, by providing a road safety barrier for motorcycle accidents that is reliable and able to minimise the injuries suffered by a motorcyclist due to impact therewith.
Another object of the present invention is to provide a safety barrier for motorcyclists that is versatile, suitable to be installed on pre-existing road safety barriers and able to adapt to a winding course.
Yet another object of the present invention is to provide such a barrier that has a long durability and at the same time is cheap and simple to produce and to install.
These objects are achieved according to the invention with the characteristics listed in appended independent claim 1.
Advantageous embodiments of the invention are apparent from the dependent claims.
The road safety barrier for motorcycle accidents according to the invention comprises:

a plurality of uprights that support a safety barrier for vehicles disposed at a certain height from the road surface,
deformable spacers of shaped sheet metal, mounted on said uprights, and
a plurality of segments of strip, of shaped sheet steel, fixed to said spacers, so as to be disposed between the road surface and said vehicle safety barrier, at a certain distance from said uprights.

The advantages of the safety barrier according to the invention are obvious. In fact said safety barrier for motorcyclists, being made of sheet steel, ensures a greater durability than the plastic safety barriers of the prior art. Furthermore it can be adapted perfectly to the existing safety barrier.
Provision of a deformable spacer, of sheet steel, considerably increases the level of safety of the safety barrier, keeping the strip at a distance from the uprights and ensuring a deformation that cushions any impact of a motorcyclist.
Further characteristics of the invention will be made clearer by the detailed description that follows, referring to purely exemplifying and therefore non-limiting embodiments thereof, wherein:

Fig. 1 is a front view of the barrier according to the invention;
Fig. 2 is a cross sectional view taken along the vertical plane of section II-II of Figure 1;
Figure 3 is a cross sectional view taken along the horizontal plane of section III-III of Figure 1;
Figure 4 is a partially broken-off front view of the strip of the safety barrier for motorcyclists according to the invention;
Figure 5 is a cross sectional view, taken along the plane of section V-V of Figure 4;
Figure 6 is a front view of the spacer of the safety barrier for motorcyclists according to the invention;
Figure 7 is a cross sectional view taken along the plane of section VII-VII of Figure 6;
Figure 8 is a perspective view of a terminal element of the strip of Figure 4;
Figure 9 is a view like Figure 2, but illustrating a second embodiment of the invention in which the spacer is fixed to the post of the safety barrier by means of U-bolts;
Figure 10 is a cross-sectional view, taken along the horizontal plane of section X-X of Figure 9;
Figure 11 is a front view of the spacer of Figure 9;
Figure 12 is a cross sectional view taken along the plane of section XII-XII of Figure 11;
Figure 13 is a plan view of a U-bolt of Figure 10; and
Figure 14 is a plan view of a closing plate of the U-bolt of Figure 10.

The safety barrier for motorcycle accidents according to the invention, indicated as a whole with the reference numeral 1, is described with the aid of the figures.
With reference for now to Figures 1 and 2, the road safety barrier 1 for motorcycle accidents according to the invention is applied to an existing safety barrier 100, such as, for example, that described in the paten application EP 1 213 391 .
The safety barrier 100 comprises a plurality of uprights 101 fixed to the ground T and spaced out along the length of the safety barrier, a spacer 102 mounted on each upright and a plurality of segments of corrugated steel strip 103 carried by the spacers 102.
Each upright or post 101 is preferably a C-shaped section, with the arms of the C disposed along the length of the road, that is, in the direction of travel of the vehicles, indicated by the arrow F in Figure 1. The uprights or posts 101 can be fixed to the ground T in any known manner, for example they can be fixed into a reinforced concrete element A, as shown in Figure 2.
The bottom edge of the corrugated strip 103 is about half a metre from the ground T, or 442 mm to be precise. Therefore, the road safety barrier 1 for motorcyclists must be disposed in the space between the ground T and the bottom edge of the corrugated strip 103.
The barrier 1 according to the invention comprises a plurality of segments of steel strip 2, suitably shaped and fixed to the existing posts 101, by means of special deformable steel spacers 3.
With reference to Figures 4 and 5, the strip 2 is obtained from a galvanised, cold-folded sheet steel, preferably having a thickness of about 2 mm. The strip 2 is substantially square wave-shaped in cross section and has two ribs 20 which protrude towards the road with respect to a flat intermediate portion 21, in order to increase the stiffness of the strip. Each rib 20 has a substantially trapezoid profile and consists of a flat surface 20 disposed between two oblique sides 22. The joins 23 between the flat surfaces 20 and 21 and the oblique sides 22 are suitably rounded, so as to avoid sharp edges. The width of the flat surface of the ribs 20 is slightly less than the width of the flat surface of the intermediate portion 21.
The thickness and the shape of the strip 2 have been specially designed to reach a compromise between a sufficient mechanical strength to withstand the impact against vehicles and at the same time to minimise the inertia and the stiffness of the resistant section, so that it can be deformed softening the impact of a motorcyclist.
The height of the strip 2 measured from its bottom edge to its top edge is about 384 mm. In this manner almost all the space between the road surface T and the bottom edge of the upper barrier 103 is covered.
The posts 101 are generally spaced out from one another with a centre distance of 2 m or less. To this purpose, the length of the strip 2 is greater than 2 m, preferably 2.1 m. Thus, in the intermediate part 21 of the strip, near its edges, pairs of holes 24 or of slots 25 are formed, having a centre distance equal to the centre distance of the posts 101, to allow the fixing of the strip 2 to the spacers 3 by means of screw or bolt means 5 (Figure 3), as will be described below. Obviously, instead of two pairs of holes (25, 24), a plurality of pairs of holes can be provided, so as to be able to adapt the strip 2 to different centre distances of the posts 101.
With reference to Figures 6 and 7, the spacer 3 is obtained from a galvanised, cold-folded sheet steel, preferably having a thickness of about 3 mm. The spacer 3 is substantially square wave-shaped in cross section and has two ribs 30 and 31 defined by flat surfaces.
The first rib 30 has a rectangular profile, so as to define a C-shaped seat able to accommodate the post 101, which is C-shaped in section. The first rib 30 is defined between two sides 31 and 32 at right angles with respect to the flat surface 30 thereof. The side 31 continues with a flange or intermediate flap 33, bent at a right angle with respect to the side 31. The side 32 continues with a flange or intermediate flap 34, bent at a right angle with respect to the side 32. The second rib 31 is defined between an oblique side 35 which joins to the intermediate flap 34 and an end side 36 at a right angle with respect to the flat part 31 of the second rib. A first pair of holes 37 is formed on the end flap 33, a second pair of holes is formed on the intermediate flap 34 and a third pair of holes 39 is formed on the end side 36.
With reference to Figure 3, the first rib 30 of the spacer 3 is disposed to abut against the post 101, then the spacer 3 is fixed to the post 101 by means of one or two rectangular plates 4 fixed to the spacer by means of screw or bolt means 41 (schematised with a dashed line) which engage in holes in the plate 4 and in the holes 37 and 38 of the end flap 33 and of the intermediate flap 34 of the spacer 3. On tightening the bolts 41, the post 101 is clamped between the spacer 3 and the closing plate 4 which abuts against the edges of the post 101.
In this manner the end side 36 of the spacer faces towards the road. The end edges of the two segments of strip 2 are placed one over the other, so that the slots 25 of a first segment of strip are placed over the holes 24 of a second segment of strip and are disposed coaxially to the holes 39 of the end side 36 of the spacer. In fact, the flat intermediate part 21 of the strip abuts against the flat end side 36 of the spacer. The bolts 5 are then inserted in the aligned holes 24, 25 and 39 and are tightened.
It should be noted that bolts with a rounded head 50 disposed in the intermediate part 21 of the strip are used, so as to avoid sharp-edged protrusions. In any case the head 50 of the bolt is disposed on the intermediate part 21 between the two ribs 20 of the strip. The tightening of the bolts 5 takes place by means of a nut 51 and of a washer 52 disposed on the end side 36 of the spacer.
Furthermore, it must be considered that this solution, which provides for fixing only with two bolts, allows portions of road with somewhat accentuated bends to be covered. In fact, the segments of strip 2 are deformed according to the radius of curvature of the bend and on tightening the bolts 5 sufficiently, no sharp edges are left between the two segments of strip.
The spacer 3 performs two important functions. In fact it keeps the strip 2 at a distance from the post 101, avoiding serious consequences in the event of impact of a motorcyclist against the strip 2 at the post 101. Furthermore, the particular shape of the spacer 3 allows deformation thereof, through the bending of the oblique side 35, in the event of impact, so as to absorb the impact gradually.
Figure 8 shows a terminal element 6 of the strip 2. The terminal element 6 comprises an end portion 60 which has the same profile as the strip 2, in cross section. Thus the end portion 60 has a flat intermediate part 61 in which two holes 62 are formed, having the same centre distance as the pair of holes 24 in the strip 2. The end portion 60 is joined to a U-shaped portion of curved sheet metal 63 which continues with a rectangular plate 64, the end flap 65 of which is bent at 90° and has two holes 66 having the same centre distance as the holes 37 of the spacer.
In this manner the end part 60 of the terminal 6 is placed over the end edge of the last strip 2 of the barrier, so that the holes 62 of the terminal are in register with the holes 24 of the strip 2 and with the holes 39 of the spacer 3. Bolts are then inserted in the respective holes 62, 24 and 39, to fix the terminal 6 to the strip 2 and to the spacer 3.
The curved part 63 of the terminal surrounds the post 101 and the end flap 65 of the terminal abuts on the end flap 33 of the spacer. The holes 66 of the end flap of the terminal are disposed in register with the holes 37 of the spacer. Then bolts are inserted in the holes 66 of the terminal and in the holes 37 of the spacer to fix the terminal to the spacer 3, which is fixed to the post 101. It should be noted that the curved part 63 of the terminal surrounds the post 101 and is kept at a suitable distance therefrom, to avoid an impact of the motorcyclist against the post.
Like or corresponding elements to those already described are designated henceforth by like reference numerals and are not described in detail.
With reference to Figures 10-14, a variant of the invention is described, in which the spacer element 3' is fixed to the post 101 by means of a pair of U-bolts 7, essentially C-shaped in section, with threaded ends 70. This solution is appropriate for adapting the spacer 3' to the different dimensions of the posts 101.
In this case the spacer 3' is essentially similar to the previously described spacer 3. In fact the spacer 3' is obtained by cutting a part of the side 31 of the spacer 3, so as to obtain an end side 31' shorter than the other sides 32 and 36. Thus the end flap 33 is not present in the spacer 3'. Furthermore, in the spacer 3' the pair of holes 38' has been moved to coincide with the join between the central flap 34 and the side 32, instead of being provided in a central position of the central flap 34.
As shown in Figure 10, the rib 30 of the spacer 3' is disposed in abutment against the post 101 and the spacer 3' is fixed to the post by means of two U-bolts 7 and of two respective closing plates 8 (Figure 14) provided with holes 80 with a centre distance equal to the centre distance of the threaded ends 70 of the U-bolt. To be precise, one end 70 of a U-bolt is inserted in the hole 38' of the spacer and the two ends 70 of the U-bolt are inserted in the holes 80 of the respective closing plate. Nuts 81 are then screwed onto the threaded ends 70 of the U-bolt so as to clamp the closing plate 8 in abutment against the ends of the post 101. A washer 82 can be interposed between the closing plate 8 and the nuts 81.
Numerous changes and modifications of detail, within the reach of a person skilled in the art, can be made to the present embodiments of the invention without thereby departing from the scope of the invention, as set forth in the appended claims.

Claims

A road safety barrier (1) for motorcycle accidents comprising:
- a plurality of uprights (101) which support a safety barrier (100) for vehicles, disposed at a certain height from the road surface (T),

- deformable spacers (3, 3'), made of shaped sheet steel, mounted on said uprights (101), and

- a plurality of segments of shaped steel strip (2), fixed to said spacers (3, 3'), so as to be disposed between the road surface (T) and said vehicle safety barrier (100), at a certain distance from said uprights (101).
A barrier (1) according to claim 1, characterised in that said strip (2) is substantially square wave-shaped, in cross section, and has two ribs (20), having a flat surface, which protrude towards the road with respect to a flat intermediate portion (21).
A barrier (1) according to claim 2, characterised in that each rib of the strip (2) has a trapezoid profile consisting of a flat surface (20) disposed between two oblique sides (22), in which the joins (23) between the flat surfaces (20) and the oblique sides (22) are suitably rounded.
A barrier (1) according to claim 2 or 3, characterised in that the width of the flat surface of the ribs (20) is slightly smaller than the width of the flat surface of the intermediate portion (21) and in that in the intermediate portion (21) of the strip (2) there are provided holes or slots (24, 25) having a centre distance equal to the centre distance between said uprights (101), to accommodate screw or bolt means (5) for fixing to said spacers (3, 3').
A barrier (1) according to any one of the preceding claims, characterised in that said spacer (3, 3') has two ribs (30, 31) defined by flat surfaces, in which the first rib (30) has a rectangular profile, so as to define a seat adapted to accommodate the post (101) which has a C-shaped section and the second rib (31) ends with one end side (36) on which said strip is fixed (2).
A barrier (1) according to claim 5, characterised in that the second rib (31) of the spacer has a profile shaped as a right-angled trapezium, with an oblique side (35) that is connected to an intermediate flap (34) between the first rib (30) and the second rib (31).
A barrier (1) according to claim 5 or 6, characterised in that holes (39) are provided in the end side (36) of the spacer to receive screw or bolt means (5) for fixing said strip (2).
A barrier (1) according to claim 6 or 7, characterised in that holes (38; 38') are provided in the intermediate flap (3) of the spacer to accommodate fixing means (41; 7) for fixing said spacer (3; 3') to said upright (101).
A barrier (1) according to claim 8, characterised in that said spacer (30) has an end flap or flange (33) disposed on the same plane as said intermediate flap or flange (34) and provided with holes (37) to receive screw or bolt means (38) for fixing to a closing plate (4) disposed in abutment against the ends of the upright (101).
A barrier (1) according to claim 8, characterised in that said fixing means (7) for fixing the spacer (3') to the upright (101), comprise at least one C-shaped U-bolt (7) with threaded ends (70) that engage in holes (80) of a closing plate (8) disposed in abutment against the ends of the upright (101).
A barrier (1) according to any one of the preceding claims, characterised in that said strip (2) has a thickness of about 2 mm.
A barrier (1) according to any one of the preceding claims, characterised in that said spacer (3; 3') has a thickness of about 3 cm.
A barrier (1) according to any one of the preceding claims, characterised in that it comprises a terminal (6) comprising:
- an end portion (60) having the same profile as the strip (2), adapted to be fixed to the edge of the last segment of strip (2) of the barrier,

- a curved U-shaped portion that wraps around the upright (101) keeping itself at a distance therefrom, and

- a portion shaped as a rectangular plate (64) ending in a flange (65) adapted to be fixed to the spacer (3).