EP2360317A2

EP2360317A2 - Absorption protective means to be installed on a guardrail to protect a motorcyclist in the event of an impact

Info

Publication number: EP2360317A2
Application number: EP11155707A
Authority: EP
Inventors: Andrea Demozzi
Original assignee: Innovazione e Ricerca per Infrastrutture Sostenibili Srl in Sigla Iris Srl; Mattioli SpA
Current assignee: Innovazione e Ricerca per Infrastrutture Sostenibili Srl in Sigla Iris Srl; Mattioli SpA
Priority date: 2010-02-24
Filing date: 2011-02-23
Publication date: 2011-08-24
Also published as: EP2360317A3; ITMI20100294A1; IT1398525B1

Abstract

There are disclosed protective means to be installed on a road or motorway barrier to protect a motorcyclist in the event of an impact against the barrier, consisting of continuous protective elements (1; 1') placed beneath the lower strip of the barrier and consisting of a box-type elongated body with an open rectangular section, where the side (2) of the box-shaped body facing the supporting stakes (5) has a longitudinal opening (14) on the whole length thereof.

A protective element (1; 1') is fixed to a supporting stake (5) by a plate (6) inserted into the protective element (1; 1') and a counter-plate (7) placed outside the protective element (1; 1') and tightened against the plate (6) by at least one bolt (7) passing through the opening (14) formed in the open side (2) of the protective element (1; 1'), to block the edges of the open side (2) of the protective element (1; 1') against a tab (9) of the supporting stake (5).

Description

The present invention relates to protective means to be installed on a road or motorway barrier to protect a motorcyclist in the event of an impact against said barrier.
Roads (and motorways) often present hazardous points for the circulation of motorcyclists; the barriers installed alongside the road (or the motorway) are valid means of containing vehicles or heavy means, but they can contribute to make the consequences of an accident in which a motorcyclist is involved more serious.
Road (or motorway) barriers are usually formed of supporting stakes (normally) fixes to the ground in an upright position, which carry spacers (which in turn carry at least one strip) and at least one longitudinal bar, placed at a greater distance from the ground than that at which the strip is situated, which contributes with the strip to contain the vehicle (car, truck, articulated truck, etc.) during a possible veering off the roadway.
In the majority of the accidents, involving a motorcycle, the motorcyclist leaves the motorcycle and slides on the road surface: it is therefore likely that the motorcyclist will impact against any barriers present roadside, incurring serious injuries. The most dangerous aspect is the impact of the motorcyclist against the stakes supporting the strips of the barrier.
In order to attenuate the impact of the motorcyclist against the barrier, various types of protections have been installed on the barrier, providing the protection only of the stakes supporting the barrier and/or the installation of a further smooth longitudinal stringer (a strip, a section bar or a tubular element) in the lower part of the barrier to afford a continuous protection.
Two types of protection are mainly used:

a protective element of soft material which covers the stake to attenuate the impact of the motorcyclist against said stake;
a smooth strip, installed in the bottom part of the barrier to prevent a motorcyclist from impacting against the stake and/or from sliding under the bottom strip of the barrier in the event of an accident.

There further exist protective means which combine the positive effects of both the above mentioned solutions by installing on the same barrier both the smooth lower strip and a soft element (usually a spacer) placed between the smooth strip and the stake. In this manner the impact of the motorcyclist against the stake is avoided and at the same time the impact against the barrier is attenuated through the controlled deformation of the elements connecting the smooth strip to the stake.
The patent no. FR 2 796 090 discloses means suitable for protecting a motorcyclist in the event of an impact against a road or motorway barrier, comprising two superimposed series of aligned tubular elements, which are connected to each other and to a stake of the barrier through fixing means (placed between two adjacent tubular elements of each series and fixed to the stake of the barrier), which carry pins, each of which is inserted into one of the tubular elements.
The German utility model no. DE 1 949 782 discloses means suitable for protecting a motorcyclist in the event of a impact against a road or motorway barrier consisting of two V-shaped strips made of metal sheet, which are connected to each other to form a closed structure fixed to the stakes of the barrier.
Between the closed structure and a supporting stake of the road or motorway barrier means suitable for (at least partially) absorbing the energy due to the impact of the motorcyclist against the barrier can be inserted.
These known protection means do not allow a motorcyclist to be adequately protected in the event of an impact, since they are not able to completely dissipate the energy due to the impact and they tend to cause the motorcyclist to be thrown back onto the roadway.
FR 2 313 503 A1 discloses a safety barrier for road and motorway comprising a plurality of posts and cross pieces fixed to the posts by means of screws which require the posts to be perforated. The cross pieces are suitably spaced along the posts and connected each other by fixing means comprising a plate and screws. Such fixing means between adjacent cross pieces are dangerous in case of impact of a motorcyclist against the barrier.
US 1 643 555 A discloses a guard comprising posts arranged at intervals along the side of a roadway and rails secured to the front faces of the posts by means of screws. The rails vertically extend along the posts and are positioned at such height over the surface of the roadway to be engaged by the hubs of a skidding motor vehicle and to stop the movement of the same. The rails consist of sections, whose meeting ends are connected by means of a bridging member and a screw with a lock nut.
WO 03/104568 A1 discloses a guide rail comprising a plurality of rail segments connected end to end by fastening means. The segments comprise on one end an end section with a reduced cross section such that the adjoining rail segments can be connected by telescoping and fastening.
These known documents all refer to a guide rail for motor vehicles and not to protective means for motorcyclists placed beneath the lower strip of a barrier, in order to protect the motorcyclist in the event of impact against the barrier, so avoiding that he leaves the roadway.
Moreover, the above listed documents provide the perforation of the posts for fixing thereon, for example by means of screws, the cross pieces, as well as the mechanical connection of adjacent cross-pieces. They present some drawbacks. First, the posts have to be perforated in loco during the connection of the cross pieces, with consequent localized loss of the anticorrosive protection, typically zinc plating, and serious decrease of the working life of the system. Moreover, being adjacent cross pieces connected therebetween by means of fixing screws, these latter are at least potentially dangerous for the motorcyclist since they protrude from the surface of the barrier facing towards the road.
Object of the present invention is to obtain protective means to be installed on a road or motorway barrier to effectively protect a motorcyclist in the event of an impact against said barrier; this object is achieved through continuous protective means placed beneath the lower strip of the barrier and fixed to the barrier supporting stakes, having the characterizing features set forth in claim 1.
Further advantageous characteristics of the invention form the subject-matter of the dependent claims.
The invention will now be described with reference to a purely exemplifying (and therefore not limiting) embodiment thereof, illustrated in the appended figures, wherein:

Figure 1 schematically shows a front view of a first embodiment of a protective element according to the invention;
Figure 2 schematically shows the protective element of Figure 1, sectioned along the section plane A-A of Figure 1;
Figure 3 schematically shows a sectional side view of the protective element of Figure 1, fixed to a stake;
Figure 4 schematically shows the assembly protective element - stake of Figure 3, sectioned along the section plane B-B of Figure 3;
Figure 5 schematically shows the junction area of two protective elements of Figure 1;
Figure 6 schematically shows a front view of a second embodiment of a protective element according to the invention;
Figure 7 schematically shows the protective element of Figure 6 sectioned along the section plane A-A of Figure 6;
Figure 8 schematically shows a sectioned side view of the protective element of Figure 6, fixed to a stake;
Figure 9 schematically shows the assembly protective element - stake of Figure 8, sectioned along the section plane B-B of Figure 8; and
Figure 10 schematically shows the junction area of two protective elements of Figure 6.

In the appended figures, corresponding elements will be identified by the same reference numerals.
A protective element consists of a box-type elongated body with an open rectangular section, where the side of the box-type body facing the supporting stakes of the barrier has a longitudinal opening (i.e. an opening parallel to the longitudinal axis of the protective element) on the whole length thereof; the box-shaped body is preferably tapered (i.e. its height gradually decreases passing from one end to the other end thereof) to allow two adjacent protective elements to be friction jointed or interference fitted each other by inserting the end of a protective element having a smaller height into the end of an adjacent protective element having a greater height.
A protective element is fixed to a supporting stake by means of a plate inserted into the protective element and of a counter-plate placed outside the protective element and tightened against the plate by at least one bolt passing through the opening formed in the open side of the protective element: the plate and the counter-plate, tightened each other by the at least one bolt, block the edges of the open side of the protective element against a tab belonging to the supporting stake,
Figure 1 schematically shows a front view of a first embodiment of a protective element 1 according to the invention, which consists of a tapered (i.e. its height gradually decreases passing from the value D at one end to the value D1, smaller than D, at the other end thereof) elongated box-type body.
The difference between the heights D and D1 is not lower than the thickness of the wall of the box-type body forming the protective element 1.
As can be seen better in Figure 5, this tapering allows two adjacent protective elements 1 to be jointed by inverting the end having height D1 of a protective element 1 into the end having height D of the adjacent protective element 1.
This allows two adjacent protective elements 1 to be friction jointed or interference fitted, in order to advantageously avoid "step-shaped" discontinuities in the junction areas of the adjacent protective elements 1, as well as the presence of bolts (or of other joining means) protruding from the surface of the barrier facing towards the road, which are at least potentially dangerous for the motorcyclist.
Figure 2 schematically shows - sectioned along the section plane A-A of Figure 1 - the protective element 1, which is rectangular in section and has the longitudinal opening 14 at its side 2 facing the supporting stake 5, when the protective element 1 is installed (Figure 3).
In Figure 2, the reference numeral 2 identifies the greater sides of the protective element 1, which are perpendicular to the road plane 4, when the protective element 1 is installed (Figure 3); the reference numeral 3 identifies the smaller sides of the protective element 1, which are parallel to the road plane 4, when the protective element 1 is installed (Figure 3); the reference numeral 14 identifies the longitudinal opening formed in the open side 2.
Figure 3 schematically shows a sectioned, side view of a protective element 1 fixed to a supporting stake 5 by means of a plate 6 inserted into the protective element 1 and of a counter-plate 7 placed outside the protective element 1 and tightened against the plate 6 by bolts 8, passing through the opening 14 formed in the open side 2 of the protective element 1: the plate 6 and the counter-plate 7, tightened each other by the bolts 8, block the edges of the open side 2 of the protective element 1 against the tab 9 belonging to the supporting stake 5, as can be seen better in Figure 4.
Thanks to this blocking way (plate and counter-plate tightened each other by a bolt) of each protective element 1 to a respective supporting stake 5, it is not necessary to perforate the stake 5. This is advantageous in terms of adaptability to each type of existing barrier, absence of localized operation which damage the existing structures, and greater duration of the system, so increasing the road security.
Advantageously, to firmly block the edges of the open side 2 of the protective element 1 between the plate 6 and the counter-plate 7, the means for fixing a protective element 1 to a stake 5 further comprise a prismatic body 10 (visible better in Figure 4) placed between the edges of the open side 2 and the area of the counter-plate 7, that contacts the edges of the side 2 when the counter-plate 7 is installed.
The thickness of the prismatic body 10 is preferably equal to that of the tab 9.
In Figure 3, the plate 6 and the counter-plate 7 are tightened each other by two bolts 8, but, without departing from the scope of the invention, the plate 6 and the counter-plate 7 can be tightened each other by a bolt 8 or three or more bolts 8.
The distance between two adjacent supporting stakes 5 must be not lower than the length of the protective element 1, but, since the plate 6 can slide inside the protective element 1, such distance can be chosen each time to better fulfil specific requirements.
This advantageously allows to obtain modular protective elements, which are unrelated from the distance between the centres of the stakes.
Figure 4 schematically shows the assembly protective element 1 - stake 5 of Figure 3, sectioned along the section plane B-B of Figure 3; in Figure 4 a section of the protective element 1, the supporting stake 5 with the tab 9, the plate 6 and the counter-plate 7, tightened against the plate 6 by the bolt 8 to block the edges of the open side 2 of the protective element 1 against the tab 9, and the further prismatic body, are visible.
In the described embodiment, the supporting stake 5 consists of a section of a 1-shaped section bar, but without departing from the scope of the invention, the supporting stake 5 can be otherwise shaped each time to fulfil specific requirements, provided that a tab 9 is present.
Figure 5 schematically shows the junction area between two adjacent protective elements 1, connected by inserting the end having height D1 of a protective element 1 (shown in broken line in Figure 5) into the end having height D of the adjacent protective element 1.
Figures 6 to 10 schematically show a second embodiment (1') of a protective element according to the invention, which differs from the protective element 1 described with reference to Figures 1 to 5 at least for the fact that the at least one portion of the smaller sides 3 of the protective element 1' is "concertina" folded, i.e. it has saw tooth longitudinal folds 12 on the whole length of the protective element 1', which resiliently absorb at least part of the energy due to the motorcyclist's impact.
The side 2' of the protective element 1' opposite to the open side 2 and facing the roadway, preferably has a longitudinal stiffening rib 13.
In Figures 6 to 10, corresponding elements have been identified with the same reference numerals used in Figures 1 to 5.
In the embodiment shown in Figures 7 and 8, each of the smaller sides 3 of the protective element 1' has three longitudinal folds 12, but without departing from the scope of the invention, each smaller side 3 of the protective element 1' can have less than three or more than three longitudinal folds 12.
The protective elements obtained according to the invention have the following innovative features:

the open section provide them with an elasticity and flexibility greater than those of a closed structure as the one described, for example, in the document DE 1 949 782 ;
they hold the motorcyclist on the roadway and make softer his impact against the road barrier, so avoiding dangerous consequences for the motorcyclist's body, as the protective elements absorb in a continuous manner (i.e. along the whole length thereof, instead of in a punctiform manner, as it is the case with the known protective elements) a great portion of the kinetic energy due to the impact, by deforming themselves in an elastoplastic manner during the impact, meanwhile maintaining their shape, which allows the motorcyclist to be re-directed, so avoiding he to leave the roadway;
they consist of modular elements preferably made of metal (but without departing from the scope of the invention they can be made of rubber or of other plastic or composite materials) having an open section which allows a continuous energy absorption during the impact of the motorcyclist against the protective means, as verified experimentally by the applicant;
"step-shaped" discontinuities are not present in the junction areas of two adjacent protective elements, which are (at least potentially) dangerous in the case of an impact of a motorcyclist;
due to the fixing, by means of friction clamp, of the protective elements to the stakes, these latter do not have any kind of perforations;
the friction joining or interference fitting of two adjacent protective elements considerably facilitates the installation of the protection means and makes it possible to avoid the presence of bolts (or of other joining means) which are (at least potentially) dangerous for the motorcyclist because they protrude from the surface of the barrier facing towards the roadway;
they can be easily adapted to any type of existing barrier, since their fixing means (plate and counter-plate tightened by at least one bolt) can be applied to any kind of stakes, provided that they have a tab, irrespective of the distance between centers of the stakes;
the energy absorption due to the plastic deformation of the longitudinal folds of the protective elements (if present) makes the impact of the motorcyclist against the protective elements particularly soft, reducing the possibility of physical injury especially in the pails most exposed to trauma, such as the neck, the chest and/or the spine;
the open section of the protective elements increases their snow load strength: in fact, the protective element, being installed on the lower portion of the barrier, are subjected to pressure in the event of snow clearing. This characteristic is particularly important for mountain roads, where snowfalls are more frequent and the need to install protective means for motorcyclist is felt strongly, given the frequency of accidents - often fatal - occurring on these roads.

In the present description it is made explicitly reference to a motorcyclist, but the protective means previously described are adapted to protect also a cyclist in the event of an impact against a barrier installed on the sides of a road.
Without departing from the scope of the invention, a person skilled in the an can make to the protective means for a road (or motorway) barrier previously described all the modifications and improvements suggested by normal experience and/or by the natural evolution of the art.

Claims

Protective means suitable for being installed on a road or motorway barrier having a lower strip to protect a motorcyclist in the event of an impact against said barrier and consisting of continuous protective elements (1; 1') for being placed beneath the lower strip of the barrier and fixed to the barrier supporting stakes (5), said protective elements (1; 1') consisting of a box-type, elongated body with an open rectangular section, a side (2) of the box-type body faced the supporting stakes (5) having a longitudinal opening (14) on the whole length thereof;
characterized in that a protective element (1; 1') is fixed to a supporting stake (5) my means of a plate (6) inserted into the protective element (1; 1') and of a counter-plate (7) placed outside the protective element (1; 1') and tightened against the plate (6) by at least one bolt (8) passing through the opening (14) of the open side (2) of the protective element (1; 1'), said plate (6) and counter-plate (7), tightened each other by said at least one bolt (8), blocking the edges of the open side (2) of the protective element (1; 1') against a tab (9) belonging to the supporting stake (5).
Protective means according to claim 1, characterized in that the means for fixing a protective element (1; 1') to a supporting stake (5) further comprise a prismatic body (10), placed between the edges of the open side (2) of the protective element (1; 1') and the area of the counter-plate (7), which contacts the edges of the open side (2) of the protective element (1; 1') when the counter-plate (7) is in place.
Protective means according to claim 2, characterized in that the prismatic body (10) has the same thickness as the tab (9) of the supporting stake (5).
Protective means according to any one of the previous claims, characterized in that the height of each protective element (1; 1') decreases passing from one end of the protective element (1; 1') to the other end thereof and in that two adjacent protective elements (1; 1') are friction joined or interference fitted each other by inverting the end of a protective element (1; 1') having a smaller height (D1) into the end of the adjacent protective element (1; 1') having a greater height (D).
Protective means according to claim 4, characterized in that the difference between said heights (D-D1) is not lower than the thickness of the wall of the box-type body forming the protective element (1; 1').
Protective means according to any one of the preceding claims, characterized in that at least one portion of the smaller sides (3) of the protective element (1') has longitudinal folds (12) extending on the whole length of the protective element (1') and suitable for resiliently absorbing at least part of the energy of the motorcyclist's impact.
Protective means according to claim 6, characterized in that said longitudinal folds (12) have a saw teeth shape.
Protective means according to claim 6 or 7, characterized in that the side (2') of the protective element (1') opposite to the open side (2) and facing the road surface has a longitudinal stiffening rib (13),