US 3881697 A
A roadside barrier for protecting vehicles against impact with a fixed roadside object such as a lamppost and for protecting fixed objects against impacts of a vehicle, comprises a support and upright barriers staggered transversely and of increasing cross-section of area in the direction of travel. Preferably the barrier is a plurality of upright posts increasing in number and/or individual cross section at different locations approaching the stationary object.
Claims available in
Description (OCR text may contain errors)
I United States Patent 11 1 1111 3,881,697 Glaesener May 6, 1975 [541 ROADSIDE SAFETY APPARATUS 3,606,258 9/1971 Fitch 2515/13.] 1 lnvenwrr Ernest Glimmer, Dudelange' g'gii'iig frfili i ilifi I: Luxembourg 3,680,662 8/1972 Walker 256/1 Assigneez Acieries Reunies dc 3,693,940 Kenda1l........ Burbach-EkhDudehnse SJ. 3,704,861 12/1972 Glaesener.... 256/1 3.1 3,784,167 1/1974 Glaesener 256/111 Luxembourg, Luxembourg  Filed: Oct. 19, 1973 Primary Examiner-Werner H. Schroeder  APPL NOJ 407,998 31:32:31, Agent, or FirmKarl F. Ross; Herbert  Foreign Application Priority Data  ABSTRACT Oct. 21, 1972 Germany 2251749 A roadside barrier for protecting vehicles against pact with a fixed roadside object such as a lamppost [g2] and for protecting fixed objects against impacts of a  F1: 256 13 l 1 vehicle comprises a support and upright barriers Sta? 1 e o I gered transversely and of increasing cross-section of area in the direction of travel. Preferably the barrier is  References Cited a plurality of upright posts increasing in number and- UNITED STATES PATENTS [or individual cross section at different locations ap- 2,088,087 7/1937 Hudson 256/1 proaching the stationary object. 2,134,624 10/1938 Royall... 256/1 3,503,600 3/1970 Rich 256/1 Claims 12 DnwinK SHEET 2 OF 3 PSLTEHTEE HAY SIQFS ROADSIDE SAFETY APPARATUS FIELD OF THE INVENTION My present invention relates to a road barrier and especially to a safety system for protecting moving traffic against impact with stationary roadside objects and stationary objects from impact with automotive and other vehicles commonly traveling at elevated speeds and with high kinetic energy.
BACKGROUND OF THE INVENTION Various systems have been proposed for preventing injury to vehicular travelers and to protect objects along the roadside from impact with a vehicle. These systems can be termed general or local depending upon their ultimate function and character. General safety systems are those which may extend for relatively long distances along the shoulder of a road or along the median strip of two-directional highways and operate by retaining the vehicle in its travel lane and preventing it from leaving the road or crossing the median into an oncoming traffic lane.
Such systems may require a multiplicity of spacedapart upright posts and guard rails spanning the posts and of a strength sufficient to absorb by deformation the impact energy of a vehicle and to prevent the vehicle from going through the guard rail or caroming thereover. The rail should not be excessively rigid, in order to limit damage to the vehicle; and it must not be of such design as simply to deflect the vehicle onto parallel traffic without reduction of speed or energy absorption.
The second type of barrier is designed for local protection and may be disposed at abutments along a traffic lane, e.g. at the start of a median strip, at the junction between a turnoff and a main traffic lane, at lightposts, stanchions, sign-posts or other uprights disposed on the road shoulder, directly upon roadways between traffic lanes, at walls and pillars of overpasses, and the like. These barriers must be of the energy-absorbing type and may consist of bodies filled with sand or a liquid and designed to receive an impact with the vehicle such that the vehicle speed is progressively reduced and all of the impact energy is not instantaneously dissipated. The deceleration of the passengers is thus held to a reasonable level and the danger of serious damage to the vehicle is minimized.
Guard rail systems are defective for these purposes since they operate efficiently only when the angle of impact is relatively small, i.e. when the vehicle is traveling generally parallel to the guard rail even on impact. The guard rail is incapable of withstanding head-on impact and consequently long lengths of guard rail must be used to protect lamp posts and the like by the deflection technique where such protection is desired. Of greater value, especially where there is a serious danger of frontal or head-on impact, is an energy-dissipating arrangement using one or more drum-shaped bodies filled with sand or another fluid and generally constituted of rubber or some other yieldable material which may be provided in the direction of vehicle travel directly ahead of the object to be protected.
There have been proposed various arrangements of this latter type in which the energy-absorbing drum is spaced above the ground on one or more posts which themselves may be rigid and frequently can intercept the vehicle with excessively sudden deceleration. In
other cases the drum may be torn away or may be ineffective on leverage grounds in the energy-absorbing interception of a motor vehicle.
OBJECTS OF THE INVENTION It is an object of the present invention to provide an improved vehicle barrier for roadways and like travel regions which is especially suitable for lessening the effect of impact upon an automotive vehicle and thereby provide greater safety for its occupant.
Another object of the invention is to provide an improved barrier for stationary objects along a roadway negotiated by vehicle travel.
It is another object of the invention to provide an improved system for protecting vehicle occupants and roadside structures against the danger of vehicle impact at relatively low cost, with high reliability, ease of replacement of the energy-absorbing means and high efficiency.
Still another object of the invention is to provide a safety device of the character described which is not only satisfactory to protect vehicle passengers but also the vehicle and is operative against vehicles traveling at high speed prior to impact with roadside objects or hazards.
SUMMARY OF THE INVENTION These objects are attained according to the present invention in a barrier arrangement wherein a plurality of impact-absorbing upright elements are sunk into the ground and are arranged in an array of increasing cross-sectional density in the direction of the stationary objects. Thus the elements increase in number and/or crosssectional size so that the resistance thus offered to bending and deflection increases toward the object. A vehicle is therefore braked with increasing force as the object is approached.
In accordance with another feature of this invention the elements are posts formed of an outer tube of sheet steel between 0.5 mm and 2.0 mm thick at least some of which are filled with a synthetic-resin foam having a density of at most kp/m (l kp l kilopond l kilogram-force). These posts extend between 0.6 m and 1.0 m above the ground and are sunk in the ground between 15 cm and 40 cm. The array has a length of at least 10 m and is preferably between 15 m and 20 m long.
According to yet another feature of the invention the elements have walls formed of two separate upright wall sheets which have vertical corrugations that define vertically elongated spaces or cells that constitute the individual elements and can be, as described above, filled with synthetic-resin foam. The cells are hexagonal and are either arrayed as a honeycomb with a higher percentge of filled cells in the direction of the object, or are of increasing cross-sectional size toward the object.
DESCRIPTION OF THE DRAWING The above and other objects, features and advantages of the invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:
FIGS. 1 and 2 are top and side-sectional views of a first embodiment of the present invention;
FIGS. 3-7 are side views partly in section showing five different embodiments of the posts according to this invention;
FIGS. 8 and 9 are top views of other embodiments of the invention;
FIG. 10 is a side view of the embodiment shown in FIG. 9',
FIG. 11 is a top view of a further embodiment of the present invention; and
FIG. 12 is a side view of yet another embodiment.
SPECIFIC DESCRIPTION As shown in FIGS. 1 and 2 a pair of roadways 11 are separated by a median strip 12 which is provided with a guard rail 13 supported on posts as described in my copending applications Ser. No. 296,653 filed Oct. 11, 1972 and Ser. No. 373,867 filed July 26, 1973.
The median strip 12 is provided with a barrier 14 comprising a base formed of a concete block 22 and a cover plate in which are sunk a plurality of upright posts 15 which are disposed in transverse rows and are staggered from row to row in the direction of vehicle travel toward the abutment. FIG. 1 illustrates how the cross-sectional density, i.e. the overall cross-sectional area of the posts 15 per unit of surface area, increases toward the guard rail 13 by reason of increase of individual post cross section and/or increase in the number of posts.
Each uniform or continuous cross-section (nonstepped) post 15 as shown in FIG. 3 comprises an outer galvanized steel tube in which a mass 16 of syntheticresin foam is molded. The posts 15 are each received in the base in a socket 17 formed of an upright cylindrical steel tube 19 welded to the cover plate 20 and in turn fitted with a bottom plate 21 so as to form an upwardly open cylindrical socket of a depth of cm. The elements 19, 20 and 21 are all heavy galvanized sheet steel having a thickness of 15 mm. The posts are similarly made of galvanized steel 0.75 mm thick and are filled with a polyurethane foam having a bulk density of 80 lcp/m in those posts closer to the object 13. The diameter of the remote posts is 100 mm, while those closer to the object 13 are 150 mm in diameter. In addition the overall height B of these posts increases from 50 cm remote from the object 13 to 100 cm closer to Ill.
As is clear from FIG. 1, the posts are not only thicker and taller near the guard rail 13, but they are more closely spaced. In this manner a motor vehicle traveling in direction 23 which collides with the endmost post will be braked at an increasingly greater rate as it approaches the guard rail 13, its kinetic energy being absorbed by the posts 15 as they bend and deform. After the accident the damaged posts can be quickly replaced by a highway crew which can cut posts of the right size from long pieces, or may simply have an available supply of variously sized posts.
FIG. 4 shows a variant form of post 15' having a metal sleeve 25 as described above which is not, however, galvanized, but is filled with polyurethane foam 16. A coating 26 of polyurethane with a nonporous skin surrounds the tube so as to protect it from corrosion. In addition the socket 17' here is a simple tube 19 set in the concrete monolith 22' which is provided with reinforcement bars 27. In this manner the breaking of monolith 22' is avoided when the post 15' is struck and fabrication is made cheaper by elimination of plate 20.
A less expensive embodiment is shown in FIG. 5 wherein the post 15 is sunk directly into a monolith 22' without a socket, but provided with reinforcement 27. This arrangement is particularly useful where protection must be provided but the chance of collision is quite slight, or where damage resulting from freezing is a great problem. Of course the disadvantage is that replacement of individual damaged posts is difficult, a problem which can be partially circumvented by providing the base 22 as a plurality of blocks which can be removed and replaced by a unit having the posts embedded in a block. Of course a new block can be cast around the posts in situ.
In FIG. 6 a socket 17" is formed of a single pointed tube 19" which is simply driven into the ground 29 and which loosely receives a post 15''. This arrangement is inexpensive and quite effective, as the socket 17" can have a length of 40 cm, exclusive of the pointed tip, so as to insure a firm seating of the post 15" in the ground. This post 15" here is hollow and is provided with a synthetic-resin cap 28 which may bear a reflector.
The arrangement of FIG. 7 has the socket 17' of FIG. 7 and the tube 15'' of FIG. 6 sunk directly in the ground 29, which may be the macadam road surface. In all cases the sockets receive the posts with sufficient play to prevent them from becoming so tightly wedged that removal is difficult.
It is possible as shown in FIG. 8 to interconnect the posts 15 with vertically corrugated metal webs 30 of galvanized sheet steel and to surround the entire array with an upright steel wall 38 so as to form a unitary arrangement that has the advantages mentioned above and presents a firm barrier ahead of the object 13.
The barrier shown in FIG. 9 comprises a pair of sheet metal walls 37 which are formed with vertical corrugations and stand next to one another so as to form elongated hexagons 35 some of which are filled with polyurethane foam 16' as described above. Webs 36 are formed between the individual upright cells 35. The walls 37 are sunk in the concrete base 22 and the cells are of continuous cross-sectional shape from top to bottom as in the above-described embodiments. Once again the size of the cells as well as the percentage of filled cells increases toward the stationary guard rail 13 for increasing impact resistance.
FIG. 1 I shows a honeycomb arrangement formed of upright metal walls forming cells filled partially as shown at 16". The overall width of the barrier here increases toward the object as does the percentage of filled cells.
The posts, cells, or the like are all shown to be upright, and in FIGS. 1l1 to be perfectly vertical. It is also possible as shown in FIG. 12 to tilt them slightly into the direction 23 of oncoming traffic, so that their axes A lie at a slight angle to the vertical. This position tends to overcome any tendency of the impacting vehicles to climb over the barrier.
The overall length A of the barrier according to the invention, in the direction of traffic flow, is at least 10 m, and preferably between 15 m and 20 m. In this manner a light car which strikes the barrier will stop after only a few meters and knocking over a moderate number of posts, while a larger truck will progress most of the way to the obstacle 13 before being brought to a halt. The posts 15 will strike the front or side of the vehicle, depending on how it impacts the barrier, and will be bent over, thereby absorbing the kinetic energy of the vehicle. These posts will not break off and leave a stub that will rip open the bottom of the vehicle, thereby opening the gas tank and creating a fire hazard, nor will they do a great deal of damage to the vehicle.
The length and width of the array depends on the type of traffic conditions dealt with, and the danger which the stationary object presents. A concrete bridge abutment in a heavily traveled area would be very thickly surrounded by such a barrier, whereas a lamppost on a rural road would need to be less heavily protected. Where it would be necessary to separate two oppositely moving lanes of traffic a barrier which not only presents increasing resistance from both ends to a central stationary object, but which also has a greater cross-sectional area toward its longitudinal center line would be provided in order to prevent a vehicle which sideswipes the barrier and is then turned by the impact from ploughing through it and entering the other lane.
1. A road barrier for protection of a vehicle and its occupants in an impact with a stationary object, said barrier comprising a support base widening in the direction of said object, and a correspondingly widening array of a multiplicity of upright elongated impactabsorbing bendable elements having lower ends mounted on said support base and each consisting of an upright bar having a lower end sunk into said support and extending below the grounds, said bars having free upper ends and being of generally continuous cross section throughout their length and being arrayed so as to provide a greater cross-sectional density per unit of sur face area close to said object than remote therefrom, said bars being spaced apart and staggered along said support base, the number of bars per unit ground area being greater close to said object than remote therefrom.
2. The barrier defined in claim 1 wherein each of said bars has a metal wall defining an upright space.
3. The barrier defined in claim 2 wherein at least some of said spaces are filled with a rigid syntheticresin foam.
4. The barrier defined in claim 3 wherein said foam is a polyurethane structure foam having a bulk density of at most kp/m.
5. The barrier defined in claim 3 wherein at least two sheet metal bodies are each formed with vertical corrugations defining a plurality of said spaces, said bodies constituting said walls.
6. The barrier defined in claim 3 wherein each of said bars includes an upright sheet metal tube constituting its said wall.
7. The barrier defined in claim 6 further comprising a plurality of sockets in the support base each adapted to receive a respective element.
8. The barrier defined in claim 7 wherein said tubes and said sockets are cylindrical and said tubes are loosely received in said sockets.
9. The barrier defined in claim 6, further comprising an upright sheet metal web interconnecting said tubes.
10. The barrier defined in claim 6, further comprising an upright sheet metal wall surrounding said array and connected to at least some of said tubes.
11. The barrier defined in claim 2 wherein said sheet metal has a thickness of 0.5 to 2 mm.
12. The barrier defined in claim 11 wherein said sheet metal is galvanized steel.
13. The barrier defined in claim 11 wherein said sheet metal is surrounded by synthetic-resin foam.
14. The barrier defined in claim 11 wherein the individual bars closer to said object have greater crosssectional areas than bars remote therefrom.
15. The barrier defined in claim 11 wherein said bars are of increasing height in the direction of said object.
16. The barrier defined in claim ll wherein said array has a length in the direction of vehicle travel of more than 10 m.
17. The barrier defined in claim 16 whereins said length is 15 to 20 m.
18. The barrier defined in claim 11 wherein the height of said bars as measured from the surface of the ground is 0.6 to 1.0 m.