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
  • E01F15/14—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 specially adapted for local protection, e.g. for bridge piers, for traffic islands
  • E01F15/143—Protecting devices located at the ends of barriers
• • 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
• • 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
  • E01F15/0461—Supports, e.g. posts

Definitions

• Safety barriers of the "guard-rail” type are currently known, which comprise a horizontal, longitudinal member, or stringer, which may consist of a strip of corrugated sheet iron mounted on uprights or posts.
• stringer which may consist of a strip of corrugated sheet iron mounted on uprights or posts.
• These safety barriers present quite safe and predictable results in the event of impact of a vehicle at angles of trajectory which are not too wide with respect to the longitudinal extent of the barrier.
• a widely adopted solution consists in setting the terminal segment of the barrier inclined downwards to the ground; this prevents a head-on collision of a vehicle with an end of the barrier at a dangerous height, but may cause the vehicle to leave the ground and even reach dangerous heights.
• barrier terminals that are able to absorb energy by means of telescoping, said terminals comprising various barrier segments which are fastened to one another in longitudinal succession by means of calibrated bolts engaged in slots in the segments; the barrier is double at least at the terminal portion, and each couple of parallel segments of the guard-rail are supported by a wooden post, which has a through hole at a certain height so as to be able to withstand impacts that are transverse to the barrier but to break under an impact of preset magnitude that is longitudinal to the barrier.
• the impact of a vehicle against the terminal causes the screws and posts to break, and the sections to telescope one over another.
• the known terminals of this type are widely used in some states of the United States, however, they have the drawback that, since a particularly high-priced type of wood must be used, the cost of such barriers is relatively high already when the wood is locally available; if they were to be transported as they are to other areas, the cost of the posts would be prohibitive, also considering that it is not possible to restore them after impact. In addition, the stiffness of the posts is anyway excessive and relatively dangerous.
• the state of the art also includes a safety barrier for motorways made of a single strip of curved section on the end of which is mounted a widened headpiece provided with a system of rollers.
• a safety barrier for motorways made of a single strip of curved section on the end of which is mounted a widened headpiece provided with a system of rollers.
• a variant of this system comprises a terminal with headpiece equipped with particular knives, which, in the event of impact of a vehicle, runs along the strip of the guard-rail so that the knives cut the guard-rail up into thin slices.
• the absorption of energy is provided by the longitudinal cutting of the strip.
• shock-attenuators are devices that are set to protect a particular object, which is considered to be dangerous or to be in a dangerous position for traffic. Shock-attenuators differ from terminals in that they present better performance and higher costs. In fact, a terminal functions only in so far as it is connected to a safety barrier, whereas a shock-attenuator may function even when it is isolated, protecting a dangerous but relatively narrow obstacle, such as the pier of a bridge or the end of a low wall.
• the aim of this invention is to make a terminal for road safety barriers which enables good absorption of energy in the event of impact, good retention of the vehicle, and hence provides a good level of safety, and at the same time may be made and restored at acceptable costs.
• the new terminal comprises a longitudinally extended strip made up of a number of barrier segments provided with elongated slots in which screws for joining the segments together are screwed at a calibrated tightening torque; it further comprises a headpiece of the terminal applied on an outermost segment; each segment is mounted on an upright or post, which is made up of two half-posts, the bottom one of which is driven into the ground for a substantial portion of its height, and the top one is mounted on the bottom one by means of a predictably breakable transverse pin, i.e. a pin having a preset breaking strength, and preferably presenting a groove which engages with a peg of the bottom half-post.
• a predictably breakable transverse pin i.e. a pin having a preset breaking strength
• a tie rod is mounted, which comprises in its length a weakened section with a predictable or preset breaking strength.
• the headpiece comprises a plate which is set transverse to the longitudinal extension of the barrier and is provided with a protruding frame for retention of the vehicle, so as to prevent a vehicle that hits the terminal from sliding sideways without being able to exploit the abso ⁇ tion of energy provided by the terminal.
• the breakable upright or post made up of two half-posts, the bottom one of which is driven into the ground for a substantial portion of its height, and the top one of which is mounted to the bottom one by means of a predictably releasing restraint, can be used in a wide variety of road safety barriers, including highway guardrails of any suitable design.
• the breakable post of this invention is not restricted to use with a particular guardrail shown in the attached drawings.
• the new terminal enables a good abso ⁇ tion of energy, and hence a considerable degree of safety, for a vehicle in the event of impact of the latter against the terminal with a substantial component of force parallel to the longitudinal extent of the barrier or guardrail.
• it has relatively reasonable production and installation costs, and it may be restored rapidly and at reasonable costs.
• Figure 1 is a broken-away side view, in reduced scale, of a motorway safety barrier terminal according to the present invention
• Figure 2 is a top plan view with respect to Figure 1 ;
• Figure 3 is a sectional view according to a plane indicated by 3-3 in Figure 1 ;
• Figure 4 is a sectional view according to a plane indicated by 4-4 in Figure 1 ;
• Figure 5 is a view of an end headpiece according to arrow referenced 5 in Figure 1.
• Figure 6 shows enlarged a detail of Figure 1 ;
• Figure 7 is a sectional view according to a plane indicated by 7-7 in Figure 6;
• Figure 8 is a sectional view according to a plane indicated by 8-8 in Figure 6;
• Figure 9 is a full-size scale representation of a predictably breakable plate, i.e. a plate having a preset breaking strength, of a tie rod of the barrier;
• Figure 10 is a top plan view with respect to Figure 9;
• Figure 11 is an enlarged side view of a terminal headpiece mounted on a barrier end segment
• Figure 12 is a top plan view with respect to Figure 11.
• a safety terminal for road safety barriers is indicated as a whole by reference 10 in the figures and is suitable for being applied to the ends of road safety barriers of the guardrail type, which comprise one or more strips of corrugated sheet metal supported by uprights or posts.
• the terminal 10 basically comprises a number of segments 12 of elastic metal strip, each of which is referenced 12a, 12b, 12c, . . . respectively, starting from the outermost segment 12a.
• Each of the segments 12a, 12b, 12c, . . ., as may be seen in Figures 3, 11 and 12, comprises a corrugated metal strip with double corrugation, with longitudinal slits or slots aligned in two parallel rows, referenced 13 and 14 respectively.
• the slots 13 of one row and the slots 14 of the other row are mutually staggered in a longitudinal direction.
• the segments of corrugated section bar, 12a, 12b, 12c are fastened together, in a per se known way, by means of bolts 15.
• a supporting upright or post is provided, respectively referenced 18a, 18b, 18c, etc., whilst the reference 18 indicates an end upright which supports a headpiece 20 applied to the end segment 12a.
• Each upright or post comprises a bottom half-post and a top half-post, respectively referenced 18' and 18" for the post 18, 18'a and 18"a for the post 18a, and likewise 18'b and 18"b for the post 18b, and 18'c and 18"c for the post 18c.
• the bottom half-posts have a bottom retaining rod or peg 16 and, set at the top, a predictably breakable pin 17, i.e. a pin having a preset breaking strength, upon which the top half-post engages.
• the pin 17 passes through registering holes of the bottom half-post and in the top half-post, whilst rod 16 is engaged in a recess 16' of the top half-post.
• the bottom half-post is made of I-section and the top half-post of channel section, whilst reinforcements 19 are provided along the flanges of the metal section which forms the top half-post.
• the tie rod 30 is stretched which is anchored with one end thereof on the bottom half-post 18' of 18 and with the other end thereof on the top half-post 18"a.
• the tie rod 30 generally comprises a cable portion, a tensioning device which is per se known, and preferably comprises a predictably breakable plate 32, i.e. a plate having a preset breaking strength, generally consisting, as may be seen from Figures 9 and 10, of a metal plate with one narrow portion 33.
• the head or headpiece 20 ( Figures 5, 11 and 12) comprises an end plate, referenced 22, which is substantially orthogonal to the longitudinal extent of the barrier and fastened to the end of the end segment of metal section 12a by means of a bottom bracket 24 and an oblique arm 25.
• the plate 22 comprises a restraining projection 26 set around the perimeter of the plate close to the latter's periphery.
• the said restraining projection has the pu ⁇ ose of restraining a vehicle which collides against the headpiece so as to prevent any lateral displacements of the vehicle that might cause it to swerve and thus fail to exploit the possibilities of abso ⁇ tion of energy of the safety terminal, with consequent greater risks.
• the restraining projection generally consists of a bent metal sheet welded to the base plate 22.
• the new terminal for guard-rails or road safety barriers is mounted with the uprights driven into the ground almost up to the full height of the bottom half-posts 18', 18'a, etc., as is indicated by the dashed line S in Figures 1, 3 and 4.
• the energy of impact is substantially dissipated by the frictional force between the elements 12a, 12b, etc., by the breaking of the bridges that separate the slots of the said elements; by the breaking of the breakable plate 32; and by the breaking of the pegs 17 of the uprights.
• the terminal may be restored relatively easily by replacing the barrier elements 12, 12a, etc. that have been deformed, by replacing the tie-rod element 30, by replacing the calibrated pins 17, and by restoring the top half-posts on them.
• the breakaway post described above can be used with guardrails having other types of segments and other types of headpieces.
• the top half-post can be formed with any suitable geometry, including a solid cross section or a rectangular channel cross section.
• the bottom half- post can also be formed with any suitable geometry, including a C-channel cross section, or a solid cross section defining a slot for the top half-post.
• the restraint can include a breakaway pin as described above, which may be formed of stainless steel, and which may use conventional retainers such as an enlarged head and a cotter pin to hold the pin in place.
• a breakable or bendable latch may be mounted to or formed on the flanges of the bottom half-post to secure the top half-post releasably in its vertical orientation.
• the disclosed system is easy to install because the bottom half-post can be driven into the ground quickly and easily, and then the top half-post can be assembled in place simply by placing it on the peg and then installing the breakaway pin.
• the breakaway posts are readily refurbished after a collision. Often, nothing is more required than to reposition the top half-post in its vertical position on the peg of the lower half-post, and then to install a new breakaway pin.

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Refuge Islands, Traffic Blockers, Or Guard Fence (AREA)
• Road Signs Or Road Markings (AREA)
• Bridges Or Land Bridges (AREA)
• Devices Affording Protection Of Roads Or Walls For Sound Insulation (AREA)

Priority Applications (1)

Applications Claiming Priority (4)

Publications (1)

Family

ID=8230907

Family Applications (2)

Family Applications Before (1)

Country Status (13)

Families Citing this family (29)

Family Cites Families (11)

• 1997
  • 1997-12-22 DE DE1997627815 patent/DE69727815T2/de not_active Expired - Lifetime
  • 1997-12-22 ES ES97830691T patent/ES2215219T3/es not_active Expired - Lifetime
  • 1997-12-22 EP EP97830691A patent/EP0924347B1/de not_active Expired - Lifetime
  • 1997-12-22 DK DK97830691T patent/DK0924347T3/da active
  • 1997-12-22 AT AT97830691T patent/ATE260373T1/de active
  • 1997-12-22 PT PT97830691T patent/PT924347E/pt unknown
• 1998
  • 1998-12-18 BR BR9807715-5A patent/BR9807715A/pt not_active Application Discontinuation
  • 1998-12-18 WO PCT/EP1998/008325 patent/WO1999032728A1/en not_active Ceased
  • 1998-12-18 CN CN98802701A patent/CN1248307A/zh active Pending
  • 1998-12-18 AU AU20545/99A patent/AU2054599A/en not_active Abandoned
  • 1998-12-18 EP EP98965283A patent/EP0968333A1/de not_active Withdrawn
  • 1998-12-18 KR KR1019997007633A patent/KR20000075573A/ko not_active Withdrawn
  • 1998-12-18 CA CA002280017A patent/CA2280017A1/en not_active Abandoned
  • 1998-12-18 JP JP53332699A patent/JP2001513160A/ja active Pending

Non-Patent Citations (1)

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