EP2532787B1 - Safety barrier for roads and method for improving the absorption of energy from a light vehicle crashing into such a barrier - Google Patents

Description

The present invention relates to a traffic lane safety barrier, including but not limited to traffic lanes on engineering structures such as bridges, and to a method for improving the energy absorption of a roadway. shock of a light vehicle against such a barrier.

Currently, there are road safety barriers to retain both heavy and light vehicles. These barriers have a level of containment said "H2", corresponding to the resistance required to retain a bus in case of percussion of the barrier.

The safety barriers are classified according to their level of restraint: the so-called H1, H2, H3 or H4 levels correspond, respectively, to the resistance required to hold a light truck, a bus, a 16-tonne truck or a heavy truck. 38 tonnes, in case of impact of the barrier. The level H2 corresponds to the restraint of a bus, it is the level of retention of the barrier BN4, barrier installed in standard way on the bridges.

The document EP0999310 proposes such a barrier designed to retain both heavy vehicles and light vehicles. To this end, it is proposed to mount, on the same riser, a low slide with a deformable spacer, and a high slide without spacer. During a shock, the lower slide is first impacted to absorb some of the shock. If the shock is important, the two high and low slides are aligned and the extensions dissociate themselves from the vertical supports to which they are fixed in a calibrated manner to obtain a strap effect. In other words, the absorption of the shock is obtained not only by the deformation of the spacers, but also by the strap effect obtained by the rupture of the binding between the riser and the vertical supports.

Such a barrier therefore requires a large deformation width to be able to benefit from the strap effect. The term "width of deformation" means the width necessary to dampen a shock of maximum energy. This width of deformation is measured in the direction perpendicular to the direction of circulation of the vehicles.

However, there are many cases in which it seeks to limit the width of deformation: for example, the right bridge piles, along the walls of tunnels and, more generally, in front of rigid obstacles disposed in the immediate vicinity of the track of circulation. In these cases, there is not enough room to allow a release of the slides and to obtain the effect of strap, because we can not remove the obstacle barrier without risking to put the rails protruding on the way of traffic

This problem also arises for the traffic lanes on the structures. Indeed, their width is limited to the maximum to limit manufacturing costs. It is therefore not possible to provide safety barriers using the strap effect of the slides to retain heavy or light vehicles. The barriers used are firmly anchored to the ground, so that the slides and the vertical supports are not detached in case of impact, even violent, including a heavy vehicle.

At present, the safety barriers arranged on the roadways of the bridges are constituted (see figure 1 ) upright vertical supports 1, firmly fixed to the ground by bolts, and provided with three horizontal slides 2. Such a barrier is illustrated in the document US 2008/283806 . These barriers are called "BN4". With a BN4 barrier, it is impossible to obtain a strap effect during a crash of a small vehicle. During a heavy vehicle collision, the posts are detached from the ground in a calibrated manner, while remaining linked to the slides.

The levels of restraint H1 to H4 are chosen to prevent the crossing of the barrier by trucks or buses and to prevent them from fall outside the bridge. However, such barriers are extremely dangerous obstacles for light vehicles having a size smaller than buses and trucks, that is to say cars. The impact of a light vehicle against such a barrier causes severe trauma to the vehicle and its passengers.

Moreover, it has been found that such barriers can be dangerous during impact of light vehicles: severity, behavior of the vehicle at the barrier exit

Indeed, according to the standards in force in France (standard NF EN1317-2), the vehicle must remain straight during and after the impact, although a low roll, pitch and yaw are acceptable. After the impact, the vehicle must be redirected to a zone defining a rectangle, also called "CEN exit box", the dimensions of which are standardized according to the vehicle. For example, the CEN exit box of a passenger vehicle has a length of 10 meters and a width equal to 2.2 meters plus the width of the vehicle and 16% of its length.

This rectangle begins at the final intersection between the rear wheels of the vehicle and the barrier ("exit of the vehicle"), and extends along the barrier. The vehicle must not cut the CEN output box by the side parallel to the barrier to meet the standard.

However, with the barriers provided for heavy vehicles, light vehicles bounce in the event of an impact and can exit the CEN output box by the parallel side, while having an exit with rolls, pitch and laces unacceptable. In addition, there are often rolled out barrels.

There is therefore currently no H2 restraint level barrier allowing a sufficient control of the behavior of a light vehicle during and after the shock, while proposing a limited width of deformation, and at an economic cost.

The invention therefore aims at providing an economic maintenance safety barrier, which makes it possible both to retain large jigs such as buses or trucks but also to absorb the impact of smaller vehicles, such as cars, without the risk that they crash completely against the barrier, and in a clutter limited general allowing installation in front of and on existing structures.

To this end, the subject of the invention is a safety barrier according to claim 1.

This barrier provides acceptable shock absorption for light vehicles, while ensuring smooth, roll-free, pitch-and-pitch, and roll-free exit behavior.

A barrier according to the invention makes it possible to better secure the structures and the occasional obstacles (bridge piers, walls, trees) along conventional traffic routes. The barrier according to the invention also makes it possible to be used in a more general manner (not necessarily in front of an obstacle or on a bridge) to allow the shock absorption of any vehicle while limiting the number of parts to be changed in case of choc.

The invention also proposes a method for improving the energy absorption of a shock of a light vehicle against a safety barrier according to the invention, consisting in absorbing at least a portion of the energy of a shock. of a light vehicle by a plastic deformation of the spacers supporting the lower slide, so that the lower slide shifts towards the supports, while the wings of restraint deformable remain in use position above the light vehicle during impact.

The method may include absorbing at least a portion of the energy of a light vehicle impact by plastic deformation of the spacers supporting the lower rail, such that the lower rail is shifted toward the carriers, while the rail upper remains in the use position, the two slides then being vertically offset, the lower slide being further away from the taxiway than the upper slide.

In the state of the art, the document DE 20 2008 011203 describes a temporary security barrier, by reference to the documents WO 2008/062196 and DE 20 2008 003 111 . The barrier comprises a protection profile that is not dimensionally stable, and it provides the lateral retention function of a simple slideway, incompatible with the restraining versatility (light vehicle / heavyweight) permitted by the barrier according to the invention. .

Similarly, the document GB 1,417,109 describes a barrier according to the preamble of claim 1, comprising supports firmly fixed to the ground, and a slide fastened to the supports via deformable spacers. The slide is arranged such that before the shock, the slide is offset vertically relative to the upper part of the support, the slide then being closer to the traffic lane than the upper part of the support. Given the dimensions given in this document, this barrier concerns only light vehicles. Thus, it is explained that the upper part of the car comes into contact with the upper slide, after hitting the median slide that dampened part of the shock. The car never goes under the upper slide. There is therefore no vertical restraint of the car. Such a barrier can not absorb both the impact of a light vehicle and the impact of a heavy vehicle.

In addition, the documents DE 20 2008 009832 and CH 693 640 describe a safety barrier with which, during the shock, the vehicle first hits the lower slide and then the upper slide, so that the slide is not offset vertically relative to the upper slide. There is no vertical restraint. Such a barrier can not absorb both the impact of a light vehicle and the impact of a heavy vehicle. The document CH 693 640 specifies that the barrier may comprise a cover integral with the slides and supports, and covering the slideways so as to form a uniform screen without vertical interruption.

Finally, the documents EP 0 999 310 and EP 0 810 325 describe a barrier similar to the document DE 20 2008 009832 .

• la figure 1, une vue schématique de profil d'une barrière de sécurité BN4 selon l'état de la technique ;
• la figure 2, une vue schématique de profil d'un mode de réalisation d'une barrière selon l'invention avant un choc d'une voiture ;
• la figure 3, une vue schématique de profil du mode de réalisation de la figure 2, après un choc d'une voiture ;
• la figure 4, un diagramme illustrant l'intensité d'un choc au cours du temps ressenti par une voiture contre une barrière de l'état de la technique et contre une barrière selon l'invention ;
• les figures 5 à 7, des vues schématiques de profil de trois variantes du mode de réalisation de la figure 2 d'une barrière selon l'invention ; et
• les figures 8 à 10, des vues schématiques de profil de trois variantes d'un mode de réalisation d'une barrière non couvertes par l'invention.

Other characteristics of the invention will be set forth in the following detailed description with reference to the appended figures which represent, respectively:

• the figure 1 , a schematic side view of a BN4 safety barrier according to the state of the art;
• the figure 2 , a schematic side view of an embodiment of a barrier according to the invention before a collision of a car;
• the figure 3 , a schematic profile view of the embodiment of the figure 2 after a shock of a car;
• the figure 4 a diagram illustrating the intensity of a shock over the time felt by a car against a barrier of the state of the art and against a barrier according to the invention;
• the Figures 5 to 7 , schematic profile views of three variants of the embodiment of the figure 2 a barrier according to the invention; and
• the Figures 8 to 10 , Schematic profile views of three variants of an embodiment of a barrier not covered by the invention.

The terms "horizontal" and "vertical" family must be understood in relation to the operational position of the safety barrier, ie when it is placed along a traffic lane, ready to to be used. The terms "transverse" or "longitudinal" families must be understood, respectively, as "perpendicular" or "parallel" to direction of vehicle traffic when the barrier is in operational position.

In general, the invention relates to a safety barrier comprising supports firmly fixed to the ground, and at least one slide fastened to the supports, preferably at least two slides secured to the supports. By "fixed firmly to the ground" is meant that the supports are not intended to fold and to separate from the slideway in the event of impact of a light vehicle, contrary to the safety barriers known and used along the tracks of the vehicle. Conventional traffic (motorway type), and using supports having a calibrated impact resistance to yield in case of accident, which allows to obtain a strap effect when the slide separates from the supports.

According to the invention, the slideway is fixed to the supports by means of calibrated deformable spacers. In addition, the supports comprise a dimensionally stable retaining flange arranged in the upper position relative to the slideway.

This is why the slide is called "lower" because it is arranged under the retaining wings, and at a height adapted to receive a shock of a light vehicle. It is arranged at level (approximately) of the center of gravity of light vehicles, it ensures its restraint and participates in the absorption of energy. The retaining wing is therefore disposed at a height greater than the height of the center of gravity of the light vehicles.

"Deformable" means that the retaining flange does not deform upon impact by a light vehicle, and remains in the position of use above the light vehicle during impact, thereby allowing restraint substantially vertical of the light vehicle. For example, the supports firmly attached to the ground and the wings are deformable are made of concrete, possibly armed.

Thus, the "indeformable" character must not be interpreted absolutely, but in a relative manner with respect to the deformable nature of the spacers. Thus, those skilled in the art will understand of what follows, that the deformable spacers must deform in case of shock of a light vehicle, while the wings "deformable" must keep their shape to maintain the light vehicle vertically.

In other words, the standard NF EN 1317-2 specifying the impact conditions for the different types of barrier, the skilled person will be able to size the structures according to the desired degree of retention, so that the retractor deforms when the impact of a light vehicle, while the wing remains in place, without deformation, when the vehicle comes into vertical contact with it. In terms of homologation tests, it will be considered that the retaining wings are indeformable during the acceptance test considered, when their dynamic deflection (displacement in the event of impact) is zero.

In case of impact of a light vehicle, the upper part of the wing will touch the top of the side of the light vehicle and press the light vehicle on the ground without deforming. Thus, the retaining wings allow a very good control of the output behavior of the light vehicle which is redirected along the barrier according to the invention smoothly, without roll, pitch or laces. The accident vehicle does not cut the trajectory of other vehicles and is not likely to generate new accidents (accidents).

The barrier is designed to hold heavy vehicles as well, the upper part of the retaining wing is equipped with an upper slide that will secure the heavy vehicle that is higher than a light vehicle.

After an impact, the lower slide is shifted vertically relative to the upper slide, the lower slide being further away from the taxiway than the upper slide. An angle is formed between the rail and the end of the retaining wing.

One embodiment of the barrier according to the invention is illustrated in figure 2 . In this figure the barrier is in the position of use, that is to say that it is installed along the edges of a traffic lane, and that it has not yet suffered any shock.

The barrier 100 according to the invention comprises supports 110 having a generally V-coated shape. In the figure, the wings 111 and 112 of the V are directed towards the traffic lane 200 to the right on the figure 2 . In other words, the trough 113 of the V is directed to the left of the figure 2 . One of the wings 112 is called "fixing wing" because it is intended to be fixed to the ground.

In general, but not exclusively, this floor is constituted by a sidewalk 210. Alternatively, the supports 110 may be sealed in the ground.

According to the invention, a lower slideway 120 is fixed to the recess 113 of the V-shaped support. This fixation is carried out by means of a calibrated deformable spacer 121. This means that the deformation is controlled both in its intensity and in its general direction, thanks to the structure (arrangement and / or thickness of the materials used). Such spacers are already known per se to those skilled in the art.

An upper slide 130 is attached to the other wing of the support. This wing is called "retaining wing" because it is shaped to hold trucks in case of impact against the safety barrier and against the upper slide.

The two slides 120 and 130 are, in operational position, aligned substantially vertically with respect to the ground. Thus, in case of shock of a truck, the two slides participate in the containment of the truck.

The case of a collision of a car against the barrier according to the invention is illustrated in FIG. figure 3 .

In this figure, the deformable retractor 121 has compressed during the shock with the car thus participating in the absorption of this shock to reduce the intensity felt by the passengers of the car.

After the shock, the upper and lower slides are offset vertically, that is to say they form an angle α between them. The the opposite side to the angle α has a length L _f equal to the deformation width, that is to say L1-L2 (L1 "minus" L2).

Thanks to the V-shaped shape, we find that the output behavior of a car is optimal (smoothly, without rolling, pitching or laces and without barrels), the output box CEN being respected, because the wing of restraint keeps the car on the ground. The risks of accident are therefore limited.

As specified above, the barrier according to the invention can be installed on a sidewalk 210. This installation is carried out so that the lower slide 120 is disposed at a distance L1 from the edge of the sidewalk this distance is the same as that at which the slides of the safety barriers of the state of the art are arranged.

As shown in figure 4 , the intensity of the shock felt by the passengers of a car is much lower with a safety barrier according to the invention compared to a security barrier of the state of the art shown in FIG. figure 1 . Indeed, with the safety barriers of the state of the art (represented by the dashed curve on the figure 4 ) passengers experience a first shock when the car hits the sidewalk. This first shock is materialized on the curve by the first vertex S1. Then this intensity decreases, the time the car travels the distance L1 between the edge of the sidewalk and the slide 2 carried by the supports 1. As soon as the car hits the slide, the intensity of the shock increases to a maximum S2 where the car is stopped by the support 1 which remains fixed and vertical.

On the contrary, with a barrier according to the invention, the intensity of the shock felt by the passengers of a car is much lower. Indeed, as shown by curve C2 (in solid lines on the figure 4 ), the passengers undergo a first shock identical to that felt with a barrier according to the invention (see top S1 of the curve). This is explained by the fact that, generally, the barrier according to the invention must be installed at the same distance L1 from the sidewalk edge as the barriers of the prior art. As with the latter, the intensity of the shock then decreases, the time that the car hitting the slide 120 of the barrier according to the invention. At this moment, the deformable retractor 121 begins its deformation by absorbing the shock. Unlike the curve C1, the curve C2 continues to decrease after the peak S1. After being totally deformed (see figure 3 ), the spacer 121 can no longer absorb the energy of the shock. At this time, the intensity of the shock increases since the car is stopped by the supports 113 of the barrier according to the invention which does not deform and remains fixed to the ground. However, since part of the shock has been absorbed by the spacer 121, the maximum intensity of the shock felt by the passengers when the car is stopped by the supports 113 (see top S3 of the curve C2) is much lower than the intensity of the impact felt with a barrier according to the state of the art (vertex S2 of the curve C1) of the figure 4 .

Thus, thanks to the differential depression of the barrier according to the invention, and the offset obtained between the lower slide, close to the support, and the upper slide further from the support, a barrier according to the invention not only reduces the intensity of the shock felt by the passengers but also to control the output behavior of the light vehicle because the retaining wing keeps the car on the ground. In addition, these effects are achieved with a barrier that can be installed in accordance with the regulations in force, including but not limited to a structure without having to widen the sidewalks and / or the bridge.

In addition, after the impact of a car, only the deformable spacers 121 and the lower slide 120 must be changed. There is no need to change the supports 110 and the upper slide 130. The barrier according to the invention is therefore economical maintenance and can be arranged along any traffic lane (not only on the structures or along the road). punctual obstacles or walls).

Other variants of a barrier according to the invention are illustrated, for example, in Figures 5 to 7 .

On the Figures 5 and 6 , the safety barrier according to the invention comprises a third slide 140 associated with the upper slide 130 via a spacer 150-151. In the variant of the figure 5 , the slide 140 is disposed above the slide 130 by the spacer 150. In this variant, it is possible to retain vehicles of very large size. In the variant of the figure 6 it is possible to retain vehicles of intermediate size between the car and the truck, such as a van. In this latter variant, advantageously, the spacer 151 may be deformable in a calibrated manner to press against the support 110 in the event of impact of a van. This calibrated deformation of the spacer 151 improves the shock absorption of such a vehicle, which should also hit the lower slide 120.

Of course, it is possible to combine the variants of Figures 5 and 6 by providing two additional slides 140, one above the slide 130 the other below the slide 130, these two slides 140 being associated with the upper slide 130 through a spacer.

The variant of the figure 7 comprises a third slide 160 fixed on the support 110 via a spacer 161, preferably deformable.

Of course, it is also possible to combine the variants of the Figures 5 and 7 by providing a fourth slide 140 associated with the upper slide 130 through a spacer 150.

Three variants of an embodiment are illustrated in Figures 8 to 10 , this embodiment with its variants not forming part of the invention.

In this embodiment, the supports 210 have a substantially vertical fastening portion 212 having a general shape "I" and intended to be fixed to the ground. The fixing portion 212 is provided with a dimensionally stable retaining flange 211 on which is fixed a slide 130 upper. A lower slide 120 is attached to a deformable spacer 221, the two slides being substantially vertically aligned in operative position. After a shock (not illustrated), the two slides 120-130 are offset vertically, the lower slide 120 being further from the the upper slide 130. Thanks to this angle α formed between the two slides, a light vehicle is retained during an impact by the retaining wing 211, so that the output behavior of the vehicle is controlled and the risks of a limited accident.

This embodiment may also comprise at least a third slide 140, associated with the upper slide 130 via a spacer 150-151. In the variant of the figure 9 , the slide 140 is disposed above the slide 130 by the spacer 250. In the variant of FIG. figure 10 it is possible to retain vehicles of intermediate size between the car and the truck, such as a van. In this latter embodiment, advantageously, the spacer 251 can be deformable in a calibrated manner to press against the support 210 in the event of impact of a van.

Of course, it is also possible to combine the variants of the Figures 9 and 10 by providing two additional slides 140, one above the slide 130 the other below the slide 130, these two slides 140 being associated with the upper slide 130 through a spacer.

This embodiment not covered by the invention is useful in places where there is no room. Nevertheless, the shock absorption may be slightly less than the embodiment of the Figures 2 to 7 according to the invention. In this embodiment, the fact that the holding wing forms an angle with the ground, and therefore the direction of traffic of the vehicles, allows optimal control of the output behavior of light vehicles.

Alternatively, the shape of the V coated can be rounded to become a form close to C.

• La barrière selon l'invention peut être réalisée en différents matériaux tels que l'acier, le bois des matériaux plastiques ou des combinaisons de ceux-ci.

The absorption of the shock by a barrier according to the invention can be measured using, for example, accelerometers conventionally used in the automotive industry to measure impacts on vehicles, especially during crash test. Thus, the skilled person knows many techniques and materials to measure the effectiveness of the barrier according to the invention with respect to a known barrier illustrated in FIG. figure 1 .

• The barrier according to the invention can be made of different materials such as steel, wood of plastic materials or combinations thereof.

Claims (5)

1. Safety barrier designed to be disposed along roads comprising, in the operational position, supports (110) designed to be firmly affixed to the ground and at least two slides (120-130) secured to the supports, wherein:

   • one (120) of said slides, namely the "lower" one, is secured to the supports (110) by means of spacers (121) that are deformable in a calibrated manner,

   • each support (110) comprises a non-deformable retaining wing (111) disposed in an upper position with respect to the lower slide (120),

   • the other (130) of said slides, namely the "upper" one, is secured to each support (110) by means of the non-deformable retaining wing (111) so that in the operational position, the two slides are substantially vertically aligned and after an impact by a light vehicle the lower slide (120) is able to shift vertically relative to the upper slide (130) whereas said upper slide remains in the deployment position above the light vehicle, the lower slide (120) then being farther away from the road than the upper slide (130), characterised in that

   • the supports have a general shape of a V on its side, the V shape comprising a wing (112), namely a "fixing wing", designed to be secured to the ground and said retaining wing (111), the wings (111-112) being directed towards the road,

   • the lower slide (120) being secured to the crux (113) of the V by means of the deformable spacers (121).
2. Safety barrier as claimed in claim 1, further comprising a third slide (140-160).
3. Safety barrier as claimed in the preceding claim, wherein the third slide (140) co-operates with the upper slide (130) via a cross-member (150-151) secured to the retaining wing (111) of the support (130).
4. Safety barrier as claimed in the preceding claim, wherein the cross-member (151) is deformable in a calibrated manner in order to absorb a part of an impact.
5. Method of improving the energy absorption of an impact of a vehicle travelling on a road against a safety barrier as claimed in any one of claims 1 to 4, comprising absorbing at least some of the energy of an impact of a light vehicle by a plastic deformation of the spacers supporting the lower slide so that the lower slide shifts towards the supports whereas the upper slide remains in the deployment position, the two slides then being vertically offset, the lower slide being farther away from the road than the upper slide.

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