Classifications

• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01F—ADDITIONAL WORK, SUCH AS EQUIPPING ROADS OR THE CONSTRUCTION OF PLATFORMS, HELICOPTER LANDING STAGES, SIGNS, SNOW FENCES, OR THE LIKE
  • E01F15/00—Safety arrangements for slowing, redirecting or stopping errant vehicles, e.g. guard posts or bollards; Arrangements for reducing damage to roadside structures due to vehicular impact
  • E01F15/02—Continuous barriers extending along roads or between traffic lanes
  • E01F15/04—Continuous barriers extending along roads or between traffic lanes essentially made of longitudinal beams or rigid strips supported above ground at spaced points
  • E01F15/0453—Rails of materials other than metal or concrete, e.g. wood, plastics; Rails of different materials, e.g. rubber-faced metal profiles, concrete-filled steel tubes

Definitions

• Road safety barriers comprising at least one horizontal wooden beam.
• the present invention relates to road safety barriers comprising at least one horizontal wooden beam.
• the main application of the invention is the production of road safety barriers, but the assembly of the elements which constitute them could be used for other uses, in particular, whenever a wooden element risks being subjected to longitudinal tensile force and / or accidental impact which could cause it to break.
• crash barriers have one or more horizontal rails, connected to posts fixed to the ground, and must withstand without breaking significant forces in the event of a vehicle impact: various classes or levels of force have been defined by national authorities of many countries, such as in FRANCE by the
• the rails of the slides consist of elements of metal profiles assembled together, to ensure continuity, and making it possible to fairly easily reach the resistance imposed for the upper level above.
• a road safety barrier of the type comprising at least one horizontal rail, composed of wooden elements which are assembled end to end and supported by posts, which rail, as taught by the WHITE patent, is no longer covered on a part of its surface with a continuous metal strip; however in the present invention said strip consists of flat rectangular plates, elongated, of small section, and fixed against the surface of the rail opposite the axis of road traffic, and in the horizontal plane passing through the axis of the smooth; certain rectangular plates constituting the continuous strip, comprise at least one deformation zone, which can give them an extra length for each length of the strip corresponding to a wooden element, with which it is associated.
• said rectangular plates comprising, at each of their ends, holes through which pass fixing bolts with the plate next link and the associated wood element, these holes are at least at one end of some of said plates, elongated.
• said elongated holes are brake lights having the smallest opening diameter "r" towards the end of the rectangular plate, in which they are drilled.
• the result is new road safety barriers of the type comprising at least one horizontal wooden beam and which makes it possible, for example, for particular sizing of the elements constituting it, to withstand static forces of at least 300 kNe tone in traction. ; whereas a single beam of wooden logs 180 mm in diameter, which constitute the wooden elements for the embodiment allowing the resistance above, holds only 200 kNewton, and the associated metal strip only which, the example which allowed the resistance of 300 kNewton has a dimension of 60 x 6 mm, only withstands 100 knewton.
• the object of the present invention is therefore not to reach only said limit indicated above, but to be able to superimpose the resistances of wood and those of steel, which is normally impossible, because these materials have coefficients different elongation.
• the present invention therefore avoids making a wooden slide of a size such that it should withstand the effort on its own, which would correspond to dimensions which are difficult to obtain, except at a very expensive cost and which, moreover, would be difficult to implement.
• the present invention effectively makes it possible, surprisingly, to superimpose the resistances of wood and those of steel: indeed, initially as illustrated by real tests such as an example is described below. afterwards, everything happens as if the wooden beam only supports the force it usually absorbs, up to a safety limit below its limit breaking, and with less deformation; then in a second t: _- ps, while the wood continues to absorb this effort compatible with this safety limit, the metal strip takes over by supporting the additional effort applied to the entire slide, up to its own breaking point.
• the wood being both the most visible part of the slide, and the first to withstand the forces by absorbing most of it, we must always consider that it is indeed wooden slides, whereas in the WHITE patent, for example cited above, it is the metal part which is predominant both in visual appearance and in resistance, and it is therefore no longer really possible to speak of wooden slides.
• the combination of the deformation zones and the elongated fixing holes, especially if these are brake lights, in the metal parts of the strip located at the rear of the arm therefore makes it possible to obtain a curve of deformation, relative to the tensile force supported by it, continuous and, without punctual stiffening of too steep slope, which would risk in dynamics to cause a premature rupture: tests have shown, for example, that in l absence of deformation zones, with lights with parallel edges only, and at the start of the tensile stresses, the bolts slide in them until they stop, and that during all this sliding, the rear lamella does not work, alone the wood deforms and absorbs stresses; but when the bolts come into abutment with the lights after the deformation of their housing in the wood, there is a very sudden stiffening of the deformation curve, then due to the low elongation allowed by the rear strip, which adds its resistance to that of the wooden beam, but which in the event of an impact vehicle, presents a certain risk of rupture at the location of this
• this metal strip associated with the wooden beam is fixed to the rear of the latter relative to the axis of road traffic: this on the one hand, makes it possible to keep the slide, its aesthetic presentation linked to that of wood, and on the other hand, gives its full effect of resistance indicated above, without risk of catching of the vehicles which would come to slide and lean on the slide during an impact for example; it is therefore not necessary to place this strip in grooves, even if these are useful and necessary, but for another purpose, only at the junctions of the wooden elements to keep them aligned, even in case of the support posts.
• Figure 1 is a perspective view of an example of an exploded complete slide.
• Figure 2 shows an example of a brake light.
• FIG. 3 is a schematic top view of the slide according to FIG. 1.
• Figure 4 is a schematic top view of another example of a slide.
• FIG. 5 is an example of test curves for sliding slides.
• Figures 1, 3 and 4 show a section of road safety barriers according to the invention: this barrier comprises, in a • known manner, posts 2 which preferably in the present invention are made of wood, supporting a horizontal rail 1 , which is composed of 3 wooden elements assembled end to end.
• This slide could include several horizontal rails of the same type.
• the posts 2 and the wooden elements 3 are represented here in the form of wooden logs, which is a preferred embodiment, but could be of different section such as rectangular or square.
• the heald elements are wooden logs having a constant diameter, for example corresponding to dimensions that are relatively easy to produce and handle l6 ⁇ , l ⁇ O or 200 mm and a length of between 1.5 and 4 m.
• the posts 2 are positioned at the junction of each of the heald elements 3 "but they could be at greater distances with junctions between elements 3 no supported by intermediate posts.
• This general presentation, as well as the connection of the ends of two adjacent wooden elements are described in a previous patent application from Etablatoriums GAILLARD, as mentioned above, No. FR 2.592.064, extended in EUROPE with its additions under No. EP 0
• the present invention essentially relates to the existence in combination with the other slide elements of a continuous metal strip 4, consisting of rectangular plates 5, flat, elongated, of small sections, and fixed against the surface of the stringer 1 opposite the axis of road traffic 13, and in the plane horizontal passing through the axis of the arm.
• some of these end holes 12, for example, those of the rectangular plates running over the major part of the length of the wooden elements 3 are, at least at one end 20, of elongated shape, said in light .
• these slots 12 are even in the form of brake slots, having the smallest opening diameter "r" towards the end 20 of the rectangular plate 5. in which it is drilled and as shown in FIG. 2 .
• the number of two is preferably of length from 22 to 30 mm, with a radius "R” of most important end drilling of 8.25 mm corresponding in fact to fixing bolts 9 with a diameter of 16 mm, and at the other end, the drilling radius "r" of said holes 12 is from 5 to 7.5 ⁇ im .
• some of the rectangular plates 5 constituting said continuous rear strip 4 comprise at least one deformation zone 8 which can give it an excess length of the strip for each length corresponding to a wooden element 3 with which it is associated.
• this deformation zone can consist of a series of folds of all shapes, made in the horizontal plane passing through the axis of the heald once put in place, and giving a possibility of extension from 4 to 20 mm for each element of heddle wood; this can be obtained for example with a fold in the form of curve forming a bridge with a radius "a" of 30 to 60 mm.
• FIGS. 1 and 3 two deformation zones 8 have been shown for a single longitudinal element of rectangular plates 5. These being of length at most equal to that of the associated wooden element 3; in this embodiment, it is then necessary to have another metal connecting piece 6 forming a splint at the rear of the stringer 1, relative to the axis of road traffic 13; this splint 6 overlaps and covers the ends of two adjacent wooden elements, and those of the two rectangular plates 5 associated with these wooden elements, to ensure their connection and their fixing by bolts passing through and enclosing both a wooden element 3 t a rectangular plate 5 and a connecting piece 6.
• a second metal connecting piece 21 can be added, also forming a splint at the rear of the stringer 1, overlapping and covering the ends of the two adjacent wooden elements, as the other part forming a joint 6, these two said metal parts 6, 21 enclosing the ends of the two associated rectangular metal plates 5.
• said safety barrier may have on its surface, corresponding to the side of the road traffic 13 another fishplate 7 in the horizontal plane overlapping two ends of wooden elements 3, and fixed to these by bolts, passing through them right through, and enclosing them between said splint 7 and the rectangular plates constituting the continuous strip at the rear of the heddle, here in the figure 2 the assembly of the ribs 6 and 21, and of the plates 5-
• the latter connecting rib 7 located on the front surface of the beam 1 is preferably embedded in grooves 10 at the ends of the wooden elements 3.
• All of these connecting ribs in number from one to three, referenced in FIGS. 6 and 7 are of known type and do not normally include lights such as the other metal plates 5. although they have holes allowing fixing them together and with the wooden elements 3 and the support posts 2.
• FIG 4 is a schematic top view of another embodiment of the slides according to the invention, but in which each wooden element 3 is associated with a rectangular metal plate 5 of greater length and projecting from said wooden element 3 at least at one end, which is deformed to cover the end of the rectangular metal plate 5 of the adjacent wooden element 3. which ends are then fixed to each other and to this wooden element by bolts passing through it from side to side.
• said safety barriers may include, in a preferred embodiment, stop bars 22, placed, vertical in the median plane of the wooden elements 3 perpendicular to the longitudinal axis thereof and to those of the fixing bolts 9, and at a given distance from those -this towards the end of the wooden elements 3. as taught and described in patent application 2,623,829 filed on November 27, 1987 by Etablatoriums GAILLARD.
• this is an example of a tensile test curve of different wooden beams, mounted according to the assembly shown in Figures 1 and 3.
• a first curve 14 representing a deformation curve of an element in wood alone, with a diameter of 10 mm, and subjected to a longitudinal tensile stress: a breaking point 17 is obtained for a tensile stress of the order of 18 tonnes for a deformation of less than 40 mm.
• the second curve 15 shown corresponds to the deformation undergone by a road safety barrier as shown in FIGS. 1 and 3 "with a 180 mm wooden log as for curve 14, but associated with a longitudinal metal element 5 of 60 mm x 6 mm; this is connected to a next element by fishplates 6 and 21, enclosing it at the ends and having the same section and now two consecutive logs of wood end to end and aligned thanks to 16 mm fixing bolts.
• One of the ends of each of the metal elements 5 is pierced with brake lights along the profile 12 as described in FIG. 2 and, these metal elements include two deformation zones 8 also described above. On this curve 15.
• test results correspond to a superposition and an addition of the resistance of the forces allowed on the one hand, by the element of wood, and on the other hand by the continuous metallic element on its rear part, with a deformation curve on exertion, continuous, without breaking of bearings risking breaks of the slide in dynamics.

Landscapes

• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Wood Science & Technology (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Refuge Islands, Traffic Blockers, Or Guard Fence (AREA)
• Road Paving Structures (AREA)
• Emergency Lowering Means (AREA)
• Road Signs Or Road Markings (AREA)
• Fencing (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9417632

Family Applications (1)

Country Status (8)

Families Citing this family (13)

Family Cites Families (15)

• 1991
  • 1991-09-30 FR FR9112282A patent/FR2681888B1/fr not_active Expired - Fee Related
• 1992
  • 1992-09-11 ES ES92920409T patent/ES2094933T3/es not_active Expired - Lifetime
  • 1992-09-11 CA CA002119269A patent/CA2119269A1/fr not_active Abandoned
  • 1992-09-11 EP EP92920409A patent/EP0606305B1/de not_active Expired - Lifetime
  • 1992-09-11 DE DE69215526T patent/DE69215526D1/de not_active Expired - Lifetime
  • 1992-09-11 US US08/211,116 patent/US5462258A/en not_active Expired - Fee Related
  • 1992-09-11 WO PCT/FR1992/000855 patent/WO1993007340A1/fr active IP Right Grant
  • 1992-09-11 AT AT92920409T patent/ATE145688T1/de not_active IP Right Cessation

Non-Patent Citations (1)

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