ENERGY ABSORBING BARRIER

Abstract: The barrier (10) dissipating kinetic energy upon impact by a moving vehicle comprises walls (16, 18, 20) defining a con­ tainer (22) closed except for a fill opening to admit water (26). Various configurations of side walls (20) are dis­ closed. The side walls are resiliently deformable to return to their original shape after being struck, the resilience, thickness and deformability of the walls tending to form a capture region (72) above and in ad­ vance of the vehicle tire to slow the tire and prevent it from climbing and vaulting the barrier.

Description: The present invention relates to an energy absorbing barrier, and more particularly to an energy absorbing barrier adapted for dissipating kinetic energy upon impact by a moving vehicle. Energy absorbing barriers are in common use for many vehicular traffic applications. Those of a semipermanent nature are heavy, difficult to install or are expensive to maintain. Barriers of this type include fixed guard rails, concrete median barriers, and special structures located in a protective array around highway signs, bridge abutments and the like. Lighter, more portable structures are less likely to absorb as much impact energy, but they are more easily installable for defining temporary traffic lanes, closing off highway construction sites, establishing pedestrian walkways, etc. A typical highway barrier comprises elongated, blocks of concrete arranged end-to-end to intercept vehicles leaving a defined traffic lane. They physically redirect the path of the vehicle and can develop severe impact forces on the vehicle occupants. Further, the side walls of the barrier slope downwardly and outwardly to provide a relatively wide base to make the barrier difficult to overturn, but this also provides a climbing surface for the vehicle tires and a vehicle has a tendency to climb and vault the barrier and pass into oncoming traffic lanes or into other restricted areas. Regardless of their shape or construction, most such barriers are made non-resilient, massive and heavy in order to positively stop vehicles. Of course, this is potentially very dangerous to the vehicle occupants. There are some barriers of the prior art designed to progressively absorb kinetic energy and thereby gradually decelerate a vehicle, but such barriers are typically relatively complex or expensive. Some are characterised by internal chambers filled with gas, liquids or other fluent materials. Others depend upon springs or internal shock absorbers. Regardless of their construction, such barriers are usually not readily adapted for interconnection to define a vehicle lane, or are characterised by side walls undesirably providing sufficient tire traction that vehicles can climb and vault such a barrier. CA-A-1,214,347 discloses an energy absorbing barrier comprising a plurality of barrier sections each defining an interior chamber for receiving fluent material, including a side wall to receive the impact of a moving vehicle for dissipating kinetic energy; and end fittings by which each barrier unit is coupled at its ends to like barrier units. The side wall is of polyethylene plastic material and is sufficiently resilient to resume a normal shape after being struck and deformed by an impacting vehicle and is made of a predetermined thickness operative upon impact by the vehicle tire to bulge the side wall material to restrain the tire from climbing and vaulting over the barrier. FR-A-1,527,375 discloses an energy absorbing barrier comprising flexible containers holding volumes of water, the containers being connected end-to-end and being, for example, fitted over vertical supporting plates mounted in a base structure, the flexible walls of the containers being exposed to receive the impact of a crashing vehicle. However, neither CA-A-1,214,347 nor FR-A-1,527,375 discloses any means of preventing separation of adjoining barrier components under impact forces. EP-A-0,125,817 discloses a lane divider for a roadway. The divider is formed by a chain of modules having elongated locking members. These are operative to link together the sections and constrain them against longitudinal movement relative to one another in the event of a vehicle impact. However, each locking member is not coupled to the opposite ends of each module, but instead is connected between the abutting ends of adjacent modules. It is an object of the invention to provide an improved energy absorbing barrier suitable for dissipating kinetic energy of a crashing vehicle, and which comprises a plurality of barrier sections coupled together end to end in such a manner as to prevent separation of adjoining barrier sections under forces arising from impact of a vehicle with the barrier. According to the present invention, there is provided an energy absorbing barrier comprising a plurality of barrier sections connected end to end, each such barrier section having walls defining a chamber for receiving fluent material, said walls including a pair of end walls and a longitudinally directed side wall made of plastic material sufficiently resilient to receive the impact of a moving vehicle to dissipate kinetic energy and resume a normal shape after being struck and deformed by the vehicle, the plastic material having a relatively low coefficient of friction to reduce traction between the side wall and the tire of the impacting vehicle, the side wall being made of a predetermined thickness operative upon impact by a vehicle tire to bulge the side wall material beyond the tire and to propagate the bulged material of the side wall in a travelling wave ahead of the tire to thereby continuously scrub against the tire and slow its advance, and to restrain the tire from climbing and vaulting over the barrier, each said barrier section being connected at its ends with the adjoining barrier sections by connection means including protuberances projecting from said end wall and overlying or underlying said complementary protuberances projecting from the adjacent said end walls of the adjoining said barrier sections, and further including, at each connection between adjoining barrier sections, a respective vertically oriented connecting pin extended through vertically aligned apertures in the respective overlapping said protuberances, characterised in that, associated with each said barrier section is an elongated strap or bar extending from said connecting pin at one end of the barrier section to said connecting pin at the other end of the barrier section, said strap or bar being coupled with said connecting pins, and thereby with the straps or bars of the adjoining barrier sections, to aid in preventing longitudinal separation of the barrier sections upon impact by a vehicle. In preferred embodiments, each barrier section includes walls defining an interior chamber adapted to be filled with water. The unfilled barrier section is relatively light and easy to transport to and from the place of use, while the filled barrier section is sufficiently heavy to resist overturning on vehicle impact. The connection means connection adjoining barrier sections render the assembly virtually impossible to overturn. The side walls of the barrier sections, in the preferred embodiments, are made of a material having a relatively low coefficient of friction. The walls are resiliently deformable for resumption of their normal shape after being struck and deformed by a moving vehicle, and exhibit a pattern of deformation which tends to trap and slow vehicle tires. The barrier may be provided with fencing or similar supplemental structures to define a higher barrier. The barrier sections can be provided with transverse or elongated reinforcing elements for reinforcement against undue flexure, and can be provided with auxiliary bias means such as springs to further assist in absorbing vehicle impact and the like. In certain embodiments, the barrier sections are configured for mounting on one or both sides of ordinary median barriers. This provides supplemental vehicle impact protection, rather than providing a substitute for the existing median barriers. Other objects and features of the invention will become apparent from consideration of the following description taken in connection with the accompanying drawings. FIG. 1 is a perspective view of an energy absorbing barrier according to the present invention, comprising a plurality of similar barrier sections connection end to end; FIG. 2 is a side elevational view of a barrier section of the barrier of Figure 1; FIG. 3 is a view taken along the line 3-3 of Figure 2; FIG. 4 is a detail longitudinal cross-sectional view of the pin coupled portions of adjacent barrier sections; FIG. 5 is a partially diagrammatic top plan view of the barrier showing individual barrier sections connected by couplers to form one side of a race course turn; FIG. 6 is a view similar to Figure 5, but illustrating use of differently configured couplers to orient the barrier sections in a generally serpentine, zigzag configuration; FIG. 7 is a view similar to Figure 6, but illustrating use of yet another configuration of coupler to orient the barrier sections in adjacent, "stacked" relation; FIG. 8 is a perspective view of a typical coupler; FIG. 9 is a generally diagrammatic side elevational view, on a reduced scale, of a barrier section fitted with an overflow compartment of diaphragm; FIG. 10 is a view similar to Fig. 9, but illustrating a barrier section fitted with a means for using the contained liquid for fire fighting or the like; FIG. 11 is a side elevational view of a barrier comprising end coupled barrier sections provided with expanded metal screening surmounting the liquid fillable portions of the structure; FIG. 12 is a view similar to Figure 11, but illustrating utilization of poles and interconnecting barrier wires instead of metal screening; FIG. 13 is an enlarged cross-sectional view taken along the line 13-13 of Figure 11, FIG. 14 is an enlarged view taken along the line 14-14 of Figure 12; FIG. 15 is a view similar to Figure 14, but illustrating an I-beam form of longitudinal connector, rather than the strap connector illustrated in Figure 14; FIG. 16 is an enlarged view taken along the line 16-16 of Figure 11, and particularly illustrating employment of a metal drain plug in the plastic material of the barrier, FIG. 17 illustrates a form of filler cap adapted to store a collapsible bag which is outwardly deployable by liquid driven from the barrier; FIG. 18 shows another embodiment of barrier section, similar to those of Figure 1, but provided with an overlying thin sheet metal covering to resist tearing of the plastic material of the barrier section, FIG. 19 is an end elevational view of a protective cover like that of Figure 18, but adapted to overlie both sides of the barrier, FIG. 20 is an enlarged view taken along the line 20-20 of Figure 18, FIG. 21 is an end perspective view of a pair of barrier sections like those of Figure 1, and coupled together for common movement by a special end fitting or coupling; FIG. 22 is a top plan view schematically illustrating end connection of three barrier sections by the end fittings of Figure 21; FIG. 23 is a view similar to Figure 21, but illustrating a pair of end couplings spaced apart by biasing means; FIG. 24 is a view similar to Figure 22, but illustrating the end fittings or couplings shown in Figure 23, FIG. 25 is a schematic top plan view illustrating a form of T-connector adapted to couple together a pair of longitudinally oriented barrier sections with a transversely oriented barrier section; FIG. 26 is a schematic plan view of a plurality of end connected barrier sections, the end one of which is provided with a protective end cap for absorbing the force of an end impacting vehicle, for example; FIG. 27 is a view similar to Figure 26, but employing a protective end cap attached to the ends of a pair of divergent strings of end connected barrier sections, FIGS. 28, 29 and 30 are end elevational views of different end connectors for connecting together barrier sections to accommodate a slope of a supporting surface, or to enable a reversal of the lateral orientation of the barrier sections; FIG. 31 is a perspective view of a conventional concrete median barrier and a barrier section of the present invention which includes an attachment connector for end coupling of the two, the components being shown in exploded relationship for clarity; FIG. 32 is a transverse cross-sectional view of a conventional concrete median barrier provided with another embodiment of the invention, this embodiment constituting a form of half section to overlie one side of the concrete barrier; FIG. 33 is an enlarged view taken along the line 33-33 of Figure 32, FIG. 34 is a view similar to Figure 32, but illustrating a pair of half sections of the embodiment of Figure 32, and overlying both sides of the concrete barrier; FIG. 35 is a top plan view of yet another embodiment of the barrier of the present invention, the barrier sections of Figure 35 being characterised by a dovetailed end connections and the barrier including a tapered end barrier section; FIG. 36 is a view taken along the line 36-36 of Figure 34; FIG. 37 is a view taken along the line 37-37 of Figure 35, FIG. 38 is a view similar to Figure 13, but illustrating an integrally molded reinforcement of the barrier section which serves as a substitute for the cable of Figure 13, FIG. 39 is a perspective view of the ends of a pair of laterally spaced apart barrier sections, such as those shown in Figure 23, but showing another form of end connector or coupling; FIG. 40 is an enlarged view taken along the line 40-40 of Figure 39, FIG. 41 is a view similar to Figure 13, but illustrating another embodiment of the barrier, and which is characterised by a vertically extending central core fillable with concrete earth or the like, FIG. 42 is a perspective view of yet another barrier section, the barrier section of Figure 42 being characterised by sloping sides lacking the traction spoiler channels seen in the embodiment of Figure 1; FIG. 43 is a view similar to Figure 27, but illustrating employment of the T-fitting of Figure 25, FIG. 44 is a view similar to that of Figure 25, but illustrating end connected barrier sections spaced apart and connected together by end connected transverse barrier sections; FIG. 45 is a perspective view of a hanger bracket for attachment to a barrier for suspending a protective covering or sign or the like adjacent the barrier side; FIG. 46 is a perspective view of a typical dolly for transporting a barrier section, as shown in side elevation in Figure 47, FIG. 48 is a view similar to Figure 34 but utilizing a different form of half barrier section not requiring the support pedestal of the embodiment of Figure 34, FIG. 49 is a perspective view similar to Figure 1, but employing superjacent upper barrier sections surmounting the main or lower barrier sections; FIG. 50 is an end elevational view of the barrier of Figure 1 diagrammatically illustrating the successive losses of traction by a vehicle tire as it encounters the vertically spaced apart traction spoilers channels, FIG. 51 is a view similar to Figure 50, illustrating a vehicle tire in full line and phantom line positions, the phantom position illustrating the loss of traction at the lowermost traction spoiler channel; FIG. 52 is a view similar to Figure 51, illustrating deformation of the barrier of Figure 1 by an essentially laterally travelling vehicle tire; FIG. 53 is an enlarged view taken along the line 53-53 of Figure 52; FIG. 54 is a view similar to Figure 52, and illustrating the manner of deformation of the barrier of Figure 1 by a vehicle tire travelling approximately at a right angle to the barrier side; and FIG. 55 is a transverse cross sectional view of a further embodiment of the present barrier, with a different side wall and upper portion configuration; FIG. 56 is a view similar to Figure 35, but illustrating a different barrier configuration; and FIG. 57-60 are partial transverse cross sectional views of yet other embodiments of the present barrier, each illustrating a different barrier configuration. Referring now to the drawings, and particularly to Figure 1, there is illustrated a barrier comprising a series of barrier sections 10, each barrier section 10 comprising generally, an elongate container having a flat base 12, a top 14, a pair of end walls 16 and 18, and a pair of side walls 20 defining an interior chamber 22, as best seen in the cutaway showing in Figure 3. The barrier section container includes a fill opening which is normally closed by a bung or cap 24, as generally indicated in Figure 1. Ballast such as water 26 or other fluent material can be admitted through the fill opening to partially or completely fill the interior chamber 22, as will be seen. Suitable drain openings closed by threaded plugs 28 or the like are located at the bottom of the chamber 22 adjacent the base 12. The base 12 is adapted to be placed upon any suitable supporting surface such as the ground or pavement. It can be fixed to the ground, as will be seen, or fixed to a structure embedded in pavement, such as to the cylindrical receptacle shown in dotted outline at 30 in Figure 1. Each barrier section 10 is widest at its base 12, and the side walls 20 slope upwardly and inwardly to form a generally horizontally oriented and narrow top 14. The barrier sections 10 are preferably molded of a plastic material characterised by high strength, resilience, and resistance to permanent deformation, such as a cross-linked polyethylene material. A very important characteristic of this plastic material is its low coefficient of friction or slipperiness, as will be seen. A suitable material for the barrier sections 10 is available under the trademark MARLEX CL-100 from Phillips Chemical Company of Bartlesville, Oklahoma. It provides high impact resistance at cold temperatures, excellent tensile strength, and resistance to weathering because of included antioxidants and ultra-violet stabilizers. The material is characterized by a relatively low coefficient of friction and good flexure. Consequently, in wall thicknesses such as are preferably used in the barrier sections 10 and its variants, a tire will typically deform the barrier and slide along its length, developing a bulge or travelling wave of side wall material which tends to trap, capture and slow the vehicle tire. This phenomenon permits more gradual slowing of the vehicle, while the slippery quality of the barrier side wall tends to prevent the tire from climbing out of its captured state. As will be seen, various barrier side wall configurations are hereinafter set forth to best capitalize on this characteristic. A barrier section made of such material is relatively light in weight, an empty or unfilled barrier section 10 approximately 33 inches high, 60 inches long, and measuring 24 inches at the base, weighing approximately 100 pounds. Two men can easily lift such a barrier section and arrange a number of the barrier sections in end-to-end relation to form pedestrian lanes at movies, amusement parks, or wherever people must line up for some purpose. A barrier section of the above dimensions completely filled with water weighs approximately 1250 pounds. This weight, plus the truncated configuration of the barrier section in certain embodiments makes it very difficult to overturn. Such a barrier section 10 is transportable by a forklift or the like, the lift fork being receivable within recesses 32 molded into the base 12, s best seen in FIGS. 1 and 2. The energy absorption properties of the barrier are adjustable by varying the materials of which it is made, or by varying its configuration or dimensions, including its wall thicknesses. Such properties are also affected by the type of fluid filling material, and the degree of filling, that is, the proportion of liquid to air. A barrier section partially filled with water includes a relatively large air space within which the water may flow on impact, and the air acts in the manner of a gas accumulator. A completely filled barrier section is relatively incompressible except through liquid escape through the fill opening, and deformation of the barrier structure. The dimensions of the fill opening can be arranged to provide a relatively rapid escape of water or a metering arrangement can be provided to more gradually dissipate impact kinetic energy, as will be apparent. The manner of empirically adjusting these factors to provide a desired rate of energy dissipation will be immediately apparent to those skilled in the art and a discussion thereof is omitted for brevity. The relative resilience of the Figure 10 barrier is important. It must retain its shape when the barrier sections are filled, it must be resilient enough to resume its shape after it has been deformed by a moving vehicle or the like, and it should be resilient enough to form a deformation bulge ahead of an impacting vehicle tire to slow its progress and prevent it from climbing the barrier. An important feature of the side walls 20 of the embodiment of Figure 1 is the inclusion of integral or molded-in traction spoiler channels 34. The longitudinally extending channels 34 are vertically spaced apart to reduce the area of potential contact between the side walls 20 and the tire of the vehicle. For example, assuming a typical 30 inch diameter vehicle tire, and the 33 inch high barrier above described, a tire will hit a rib 35 defined between the pair of uppermost channels 34. This rib 35 has a small surface area compared to the tire tread area presented by the sloping flat side walls of prior art concrete barriers. In the barrier, the area of tire traction is only that presented by the ribs remaining after formation of the recessed channels 34. As a consequence, it is much less likely that a tire will climb up a side wall 20 and vault the vehicle over the barrier. The deformability and low coefficient of friction of the material of the barrier are surprisingly effective in resisting the tendency of a vehicle tire 66 to climb and vault the barrier. More specifically, as seen in Figures 50 and 51, the lateral component of movement of the vehicle tire 66 is shown by the arrow 68. The lower inward periphery of the tire 66 is seen to initially engage the lowermost rib 35, thereafter climbing upwardly from the full line position to the phantom line position. Upon attaining the phantom line position, the tire suffers an immediate loss of traction in the area of the lowermost traction spoiler channel 34. This loss of traction, and consequent resistance to further upward climbing, is denoted in Figure 50 by the curved arrow 70. As the lower edge periphery of the tire 66 engages or comes into alignment with successive channels 34, the successive losses of traction are represented by the other arrows 70. It has been found that the loss of traction provided by the spoiler channels, coupled with the slipperiness of the barrier material, substantially prevents undesirable climbing and vaulting of the barrier. As previously mentioned, there is another characteristic of the barrier which further acts to slow the travel of a vehicle tire 66 and prevent it from vaulting the barrier 10. This characteristic is present regardless of the configuration of the barrier side wall. More particularly, Figure 52 schematically shows the dynamics of a tire 66 striking the barrier at a relatively shallow angle of convergence, but with severe force so that it penetrates rather deeply into the barrier. The material of the barrier deforms to absorb the impact energy developed by the tire 66, but the deformation is such that the upper portion of the barrier, particularly including the uppermost rib 35, defines an overhang which tends to entrap or capture the tire to prevent it from climbing. The low coefficient of friction of the material of the barrier also aids in this respect, providing scrubbing or slowing engagement with the tire to slow its forward movement. As seen in Figure 53 there is also a dynamically formed travelling wave or bulge 72 located in advance of the vehicle tire 66. This is caused by deformation of the resilient material of the barrier and it tends to move in advance of the leading portion of the tire 66, scrubbing against it and slowing its forward progress. The barrier resilience and low coefficient of friction are also important in a situation where the vehicle tire 66 is travelling at substantially a right angle to the barrier. In this eventuality, as seen in Figure 54, the barrier side wall deforms in somewhat the same manner as described in connection with Figure 52, but to a much greater extent. Consequently, the undeformed upper rib 35 overlies more of the tire. Again, the low coefficient of friction of the material of the barrier acts to reduce the tendency of the of the tire 66 to climb upwardly upon the barrier side wall 35. Although the channel 34 and rib 35 configuration of the barrier sections 10 of Figure 1 is preferred because of the tire traction losses described in connection with the showing of Figure 50, in certain applications the deformation capability and low coefficient of friction of material of the barrier are sufficient for certain barrier applications. Such a modified configuration is illustrated in Figure 42. The modified barrier section 74 is like the barrier sections 10 in all respects except that it is characterised by, generally planar upwardly and inwardly sloping side walls 20a. The walls 20a deform in the manner shown in Figures 52 and 53. A lower case letter, such as the "a" in 20a is used throughout this specification to denote structures which are essentially the same in function but not in construction. The modified configuration of Figure 42 also includes, as shown in phantom outline at 76, a concave molded-in configuration which tends to provide a straight wall when the barrier section is filled. Water or other filling material tends to bulge or outwardly deform the side walls of the barrier section. By starting with a molded-in concave shape, outward bulging of the sides of the filled barrier section is avoided. Further resistance to outward bulging can be provided by molding a cable 65 into the material of the barrier section, as seen in Figures 1-3. One such cable 65 is located in each barrier section side wall approximately half way between the top 14 and base 12. Although each cable 65 is tensioned to resist outward bulging it can move inwardly or outwardly on deformation of the barrier by an impacting vehicle. Figure 13 illustrates another arrangement to provide side wall resistance to outward bulging. In this embodiment one or more transverse cables 78 are connected between the side walls 20, each being collapsible on inward deformation of a side wall 20. Figure 38 illustrates yet another arrangement to eliminate side wall bulging. A modified barrier section 80 includes an integral, molded-in, transversely disposed wall or web 78a which extends between the opposite side walls of the barrier section. The web 78a may be made continuous along the length of the barrier section 80 or it can be molded in discontinuous sections at longitudinally spaced intervals. It is preferably flexible or resilient so that it can collapse upon vehicle impact against the barrier. The energy dissipation properties of the barrier can be further modified by end coupling a plurality of barrier sections. Depending upon how the barrier sections are oriented, the assembled barrier sections are adapted to define a straight or curvilinear traffic lane, a race course, a median barrier, or stacked barrier for absorbing relatively high velocity impact forces. Although various means may be visualized for end coupling the barrier sections, one suitable arrangement comprises the hinge pin assembly seen in Figure 1. The end wall 16 includes three vertically aligned, integrally molded knuckles or protuberances 36 separated by intervening recesses 38. The opposite end wall 18, as best seen in Figures 2 and 4, include two protuberances 36 and three recesses 38, the two protuberances being adapted to fit within the pair of recesses 38 of the end wall 16 of an adjacent barrier 10. A section of aluminium tubing or the like is integrally molded or press fitted within a suitable vertical opening in each of the protuberances 36 to form pin bushings 40. The bushings 40 are vertically aligned to receive a pipe or connecting pin 42. If desired, each pin 42 can be made long enough to extend down into a receptacle 30 which is located in the underlying pavement or ground, or it can be driven into the ground or other supporting surface. Flag poles 44 can be inserted into the upper open ends of each pin 42, as seen in Figure 1, to better identify the location of a race course, for example. Alternatively, longer pins 42a, as seen in Figures 11 and 12, can be employed, the portions projecting above the barrier tops 14 providing supports for shielding or protective fencing 82 to provide a visual barrier, to isolate people from a restricted area, to offer protection against vehicle parts or debris flying across the tops of the barrier sections 10, or to add additional protection against vaulting or ramping of vehicles over the barriers. Instead of the fencing 82 illustrated in Figure 11, longitudinally disposed cables 84 can be employed to further protect against vaulting or ramping vehicles, the cables 84 being strung between and connected to the upwardly projecting portions of the rods or pins 42a, as seen in Figure 12. As illustrated in Figures 11, 12, 14 and 15, a plurality of elongate bars or straps 86 overlie respective barrier sections 10, the bars 86 overlie respective barrier sections 10, the bars 86 being long enough so that their ends overlap. In addition, the bar ends are provided with apertures for receiving the pins 42a to integrally fix the bars 86 in position on top of the barrier tops 14. The bars 86 bear a portion of the impact forces developed upon the hinge knuckles or protuberances 36 by the pins 42a upon vehicle impact. By reason of this function, the bars 86 substantially prevent any structural failure of the protuberances 36 which might otherwise occur when the pins 42a act upon the protuberances 36. For additional strength the straps 86 can be made in channel form 86a, as illustrated in Figure 15, the channel shape providing even more resistance to longitudinal bending. Figures 11 and 12 also illustrate a modified form of filler cap 24c, as best seen in Figure 17. The cap 24c is characterised by an upwardly open cylindrical body 88 which is threadably associated at its upper extremity with the barrier top 14. The hollow interior of the body 88 includes a normally open vent plug 90 in its base. A flexible container or bag 92 is carried or housed within the body 88 and is fluid coupled to the vent plug 90. With this arrangement, water expulsion from the barrier section 10 upon vehicle impact will pass through the plug 90, fill the bag 92 and thrust it upwardly and outwardly of the barrier top by popping off a disk 94 which normally overlies and closes the hollow interior of the body 88. The bag 92 is preferably made of resilient material so that it will forced the expelled fluid back into the barrier 10 subsequent to vehicle impact. Figure 16 illustrates another feature of the barrier section 10 of Figures 11 and 12. More particularly, the drain 28 is characterised by a threaded shank 96 provided with a blind bore 98. If after long service the drain cannot be removed, the bore 98 can the threaded to receive a replacement plug. End connected barrier sections 10 are preferably relatively movable to a certain extent to conform to uneven terrain. For this purpose a predetermined, relatively generous clearance is provided between the adjacent horizontal surfaces of the interconnected protuberances 36, between the protuberances 36 and the adjacent vertical walls of the recesses 38, between the surfaces of the adjacent end walls 16 and 18 of the end coupled barrier sections 10, and also between the pin 42 and the bushings 40. Such clearances enable the barriers to be arranged slightly out of longitudinal alignment to define a gradual curve of relatively great radius, or to fit closer together at their bottoms than at their tops for gentle terrain rises, or to be vertically offset to also accommodate terrain unevenness. Where it is desired to arrange the barriers in a more pronounced change of direction, that is, one of short radius, the specially configured coupler 48 of Figure 5 can be used. The coupler 48 is preferably an empty, easily movable hollow body molded of the same material as the barrier sections 10, although it could also be made for filling, as will be apparent. Its end faces or walls correspond to the barrier section end walls and are characterised by a complemental configuration and arrangement of protuberances and recesses. Lower case letters are employed in Figure 8 to show this correspondence. The coupler 48 can be made with its end faces or walls 16a and 18a defining any desired included angle. In Figure 5 the end faces are arranged at an angle of approximately 30°, the single coupler 48 being connected between the ends of adjacent barrier sections 10 by a connecting pin 42. The resultant curve has a radius of approximately 52 feet. Figure 6 illustrates yet another form of coupler, the end faces of the pair of couplers 50 defining an included angle of somewhat less than 90°. Each pair of couplers 50 are connected to each other and to the ends of adjacent barrier sections 10 by three pins 42. This orients the connected barriers in a serpentine, zigzag or loosely stacked arrangement such that impacting vehicles are gradually decelerated by successive collapsing or closing movement of the barriers against each other. Assuming the vehicle is approaching from the top, as seen by the viewer in Figure 6, the first barrier section 10 would absorb a portion of the kinetic energy, swing toward the second barrier section 10, that barrier section would further dissipate kinetic energy, and so on as the stack collapses to a closed configuration. Figure 7 illustrates an arrangement of connected barrier sections and couplers 52 in which the coupler end faces define an included angle of approximately 90°, a pair of couplers 52 being used between the ends of each pair of adjacent barrier sections. With this arrangement the barrier sections 10 are placed with the side margins of their bases 12 closely adjacent. The resulting barrier stack provides a concentrated mass able to absorb very high impact forces and prevent even large vehicles from passing through the barrier stack. In addition to the described different barriers and different orientations to alter the character and degree of kinetic energy absorption, further adjustments in kinetic energy absorption are possible by filling the successive barrier sections 10 with successively greater quantities of water, the nearest barrier section 10 being filled with less water and the last barrier section 10 being completely filled. Many variations are possible, as will be apparent. The construction of the barrier section 10 suits it for highway use, but is also is suited for use in defining a vehicle race course. As compared with barriers of the prior art, the barrier sections 10 are relatively inexpensive, easily transportable in their unfilled state, quickly connectable in a variety of arrangements, as above described, and fillable with water to various degrees. Disassembly and movement of the barriers to other sites is easy, the drain fittings 28 being opened to empty the barrier sections prior to their removal. Figure 18 illustrates yet another embodiment 100, the barrier section 100 being identical in substantially every respect to the barrier sections 10 of Figure 1, except that the end wall 16a is modified to provide improved resistance to bending under vehicle impact and thereby reduce consequent loading of the knuckles or protuberances 36 by the pin 42 (not shown in Figure 18). Such improved resistance to bending is provided by integrally molding on opposite sides of each protuberance 36 a rectangularly shaped recess or box section 102 whose walls resist such bending. The number of protuberances isa increased to four in the barrier section 100 to better distribute the forces imparted to the end wall 16a by the action of the pin 42 (not shown) against the protuberances 36. Figure 18 also illustrates use of a thin side sheet or shield 101 of metal or tear resistant rubber or the like to protect the barrier side wall 20 from gouging and tearing by the action of an impacting vehicle. The shield 101 is configured to complementally fit the configuration of the barrier side wall 20. The side shield 101 is supported in position by any suitable means, such as by a plurality of self-tapping screws 104 disposed through an elongated bar 106 overlying the upper, inwardly formed margin of the shield 101. The screws 104 self-tap into the barrier 100. Figure 19 illustrates another form of side shield 101a similar to the shield 101, except that the shield 101a is an integral or one piece shield to overlie the barrier top 14 and both side walls 20. Referring now to Figure 21 an end coupler 108 is illustrated which is similar in function to the coupler 52 illustrated in Figure 7. The coupler 108 includes at its opposite margins complemental protuberances and recesses for mating with the protuberances and recesses in the end wall 16a of side abutting barrier sections 100. A similar end coupler 108 is located at the opposite ends of the barrier sections 100 so that the end couplers 108 connect together the adjacent barrier sections 100 as an integral unit to resist impact forces beyond the capability of a single barrier section 100. Figure 22 illustrates a schematic coupling of three barrier sections 100, it being apparent that as many barrier sections 100 can be coupled together as needed for the particular application. Figures 23 and 24 illustrate another form of end coupler 110. A pair of such couplers 110 are shown mounted to the ends of a pair of laterally spaced apart barrier sections 100. The couplers 110 are secured in position by the pins 42 which pass through the protuberances 36 (not shown), the pins 42 also passing through suitable openings in the couplers 110. In addition, each coupler 110 includes three transverse openings which receive a corresponding plurality of transverse tubes 112. The tubes 112 of each coupler 110 are transversely aligned, and three compression springs 114 are disposed between the confronting tubes 112 at each end of the pair of couplers. Three rods (not shown) are disposed through the tubes 112 and the springs 114 at each end. With this arrangement, a plurality of laterally spaced apart couplers 110 are adapted to serially absorb and pass on the impact forces developed when the outermost coupler 110 is struck by a vehicle, the springs 114 compressing as this occurs. Figure 25 illustrates another form of fitting or T-coupler 116 adapted to be connected to three barrier sections 100 by three pins 42 so that one transverse barrier section 100 can be joined at right angles to a spring of longitudinally arranged barrier sections 100. Such an arrangement could be used to more strongly constrain the transverse barrier section 100 against movement upon vehicle impact, or it could be used to define right angular paths for pedestrian traffic. The barrier of the present invention is adapted to incorporate various improvements and modifications for a variety of special applications. Referring to Figure 26, two barrier sections 100 are shown connected in end-to-end relationship by a pin 42, the end section 100 being provided with a hemispherical end cap 118 connected by a pin 42 to its free end. The end cap is adapted to deflect a vehicle impacting against the end of the spring of barrier sections 100 and absorb a portion of the impact forces. Figure 27 shows an arrangement similar to that of Figure 26 but two pairs of end connected barrier sections 100 are employed, the two strings converging and being joined together by a protective end coupler or end cap 120 connected to the adjacent barrier sections 100 by pins 42. The V-shaped barrier assembly is disposed in advance or ahead of an object 122, such as a highway lighting standard, bridge abutment, or the like. A pair of tension springs 124 are connected at their outer ends to a pair of the pins 42 of the oppositely located strings of barrier sections 100. The inner ends of the springs 124 are fixed to rods 126 which are fixed or otherwise anchored to the underlying highway pavement. When a vehicle impacts against the end cap 120, the V-shape barrier assembly will be driven toward the object 122, extending the springs 124. Thus, impact energy is absorbed by the resistance of the barriers 100 to sliding movement over the pavement, as well as by energy absorption upon elongation of the springs 124. Figures 28 through 30 show different end connectors 48a, 48b and 48c. They are similar to the end connectors of Figure 5, except that the protuberances 36 are oriented so that they will dispose the barrier section to which they are connected at an angle of approximately two and a half degrees to the supporting surface for the barrier. The protuberances 36b are similarly arranged, but at a greater angle, such as approximately five degrees. Differences in terrain elevation are thereby accommodated. The protuberances 36c of Figure 30 are substantially the same on both sides, rather than complemental, as was the case in Figures 28 and 29. With the arrangement of Figure 30, the direction of orientation or curvature of the assembled barriers can be reversed, compared to the direction shown in Figure 5, so as to form an "S" configuration. Figure 31 is illustrative of the means by which a barrier section 100 can be end connected to a typical concrete median barrier 128. An attachment connector 130 having a configuration approximating that of the configuration of the concrete barrier 128 includes a back wall which incorporates a plurality of hinge knuckles 132 adapted to receive a pin 42, which also passes through a suitable opening in the top of the connector 130. The barrier section 100 and the end connector 130 are ten longitudinally moved until the connector 130 overlies the end of the concrete barrier 128. In this position suitable openings 134 in the connector are aligned with lead anchors 136 located in suitable openings provided in the concrete barrier 128. Fasteners (not shown) can then be used to secure the barrier section 100 in position adjacent the concrete barrier 128. Figures 32 and 33 illustrate a half barrier section 138 having the channels 34 and ribs 35 of the barrier section 10 of Figure 1, but only constituting a fillable outer shell for a concrete barrier 128. The half barrier section 138 includes upper and lower flanges 140 and 142 adapted to be connected to the top and base of the concrete barrier 128 by suitable fasteners disposed into lead anchors 136. The half barrier section 138 is closed at its opposite ends so that the half barrier section 138 can held water or the like. Since the half barrier sections 138 are supported in position by the concrete barrier 128, their abutting ends can be secured together by dovetail projections 144 or the like on one end of a barrier section 100 which fit into dovetail recesses 146 in the end of the adjacent half barrier section 138. Preferably the end one of the half barrier sections 138, designated by the numeral 148, is convergent, as seen in Figure 33, terminating in an end 150 approximating the configuration of the adjacent portion of the concrete barrier 128. This arrangement permits deflection and gradual absorption of the impacting force of a vehicle striking the end 150 of the half barrier section 148. Figures 34 and 36 are illustrative of the use of two half barrier sections 138, one located on either side of the concrete median 128. In addition, if the size of the half barrier section 138 is to be made greater, such as is indicated in phantom outline at 138a in Figure 34, the base of the half barrier section 138a can conveniently be supported by a pedestal 152 underlying the half barrier section 138a and resting upon the highway pavement 154. Figures 35 and 37 illustrate a similar arrangement, this time the two half barrier sections 138 of Figures 34 and 36 being replaced by a unitary shell barrier section 156 of inverted U-shape which is fluid fillable and which rests of its own weight upon the top and sides of a concrete barrier 128, shown in phantom outline, without any necessity for fasteners. In addition, the shell barrier section 156 is also adapted to overlie a typical elongated guard rail 158 supported upon a series of posts 160, as shown in phantom outline. In this application, the pavement would be located as shown in 154a. Thus, the barrier sections 156 and uniquely adapted for use with either the conventional concrete barrier 128 or the conventional, widely used guard rail 158. Figures 39 and 40 show a variation on the arrangement of Figures 23 and 24. In the embodiment of Figures 39 and 40, the end couplers 110a not only include hinge protuberances and recesses on one side, as in the case of the end couplers 110, but include them on both sides so that the pins 42 can be used to end connect adjacent barrier sections 100. Further, as best seen in Figure 40, the transverse rods in the arrangement of Figures 23 and 24, seen in Figures 39 and 40 as rods 160, extend through the springs 114 as before, but the tubes 112 are eliminated and circular recesses or seats 162 are provided in the sides of the end couplers 110a to seat the adjacent ends of the springs 114. Figure 41 illustrates a modified form of barrier section 110a which is substantially identical to the barrier section 100 except for the inclusion in the barrier section 100a of an integral, vertically oriented and longitudinally extending central core 164. The core 164 is upwardly open so that it can be filled with concrete or the like, if it is desired to add more mass, or it can be filled with earth for planting to suit the barrier to decorative applications. Figure 43 is a variation on the embodiment of Figure 27, and is characterized by an end cap 120 attached to the adjacent end of springs of end connected barrier sections 100 arranged in divergent, V-shape configuration, the adjacent ends of each string of barrier sections 100 being connected together by a coupler 116 like that illustrated in Figure 25. A specially sized and configurated barrier section 166 is pin connected to the confronting T-shape couplers 116. Figure 44 is illustrative of yet another arrangement of previously described components. In this case the barrier sections 100 are end connected in two parallel strings of barrier sections 100. A transverse string of barrier sections 100 is connected to the first pair of strings by a pair of the T-shape couplers 116/ Such an arrangement could be utilized as a barrier for runaway trucks travelling in the direction of the arrow 168. The truck impacting the transverse string of barrier sections 100 not only must deform and move the transverse barrier sections 100, but must also progressively drag the parallel strings of barrier section 100, whereby a very great impact force can be progressively absorbed and dissipated. Figure 45 illustrates a protective bar 169 which could be used as a sign support or in place of the protective side shield 102 of Figure 18, the bar 169 including lateral arms which can be pin connected to the adjacent barrier section 100 by the usual pins 42 (not shown). Figure 46 shows a form of dolly 170 which can be used to underlie a barrier section 100. The barrier section is supported upon the cross members 172 of the dolly for rolling back and forth upon the dolly wheels 174. As seen in Figure 47 this arrangement can be used to provide a form of movable gate, the movable barrier section 100 being moved between open and closed positions to open or close off a protected area. Figure 49 illustrates how a plurality of extension barrier sections can be end connected and stacked on top of the basic barrier sections 100 to provide a relatively high composite barrier especially suited to intercept flying debris or like objects, or to block unwanted viewers or traffic sounds or the like. The extension barrier sections 176 are essentially identical in every respect to the previously described barrier sections 100, except for their generally vertically oriented side configuration. They may or may not be filled with fluid, as desired. Figure 48 illustrates an enlarged half barrier section 178 similar to the enlarged half barrier section 138 of Figure 34. It is mounted to a concrete barrier 128 by fasteners 180 and 182 passing into lead anchors 136 in the barrier 128. The lower portion of the half barrier section 178 includes an integral, molded-in passage 184 to permit installation of the fastener 182. The portion of the barrier section 178 adjacent the outer end of the passage 184 slopes downwardly and inwardly to form a support portion 186 which rests against the base of the barrier 128 to transmit the weight of the filled half barrier section 178, thus eliminating any need for the pedestal 152 of the embodiment of Figure 34. The side configuration of the barrier can be varied to suit special situations. For example, in Figure 55, a barrier 188 is provided which has more closely spaced channels 34a and protuberances 35a, with the plane within which the outer faces of the tubs 35a lie being generally inwardly and upwardly directed, and intercepting a laterally projecting, overhanging capture portion 190. The portion 190 overlies all of the subjacent ribs 35a and forms an overhang which aids in preventing vaulting or leaping of the barrier 188 by a vehicle tire. The capture portion 190 is similar to the upwardly located rib 35 illustrated in Figure 52 for constraining upward movement of the vehicle tire 66. Figure 57 illustrates a barrier 188 provided with a protective strip 192 of metal, rubber or fibreglass to protect the plastic material of the barrier 188 from tearing, gouging or similar damage by an impacting vehicle. The connecting portion 194 extending between the mouth of the upper recess 34a and the capture portion 190 of the barrier 188 is generally curvilinear. In contrast, the barrier of Figure 58 includes a connecting portion characterised by a generally inwardly directed face 196 merging with a generally downwardly directed face 198, which merges with a generally inwardly directed face 200, thereby forming longitudinally extending bends or seams 202 and 204. These form a box section more resistant to bending, as compared with the curvilinear connecting portion 194 of Figures 55 and 57. Figure 59 illustrates a barrier 188 like that of Figure 55, except that the box section is defined by configuring the outer face of the upper portion 190 to form an inwardly directed channel 206 which is resistant to deformation or bending, and thereby is better able to maintain its shape and constrain a vehicle tire against upward travel. Figure 56 illustrates a barrier 208 having side configurations like that of the barrier 188 of Figure 55, except that it is adapted to rest of its own weight on a concrete barrier 128 in a manner like the shell barrier 156 of Figure 35. Figure 60 shows another embodiment of the barrier of the present invention, in this case a barrier particularly adapted to absorb the impact of a motor vehicle striking it at substantially a right angle. At this angle a vehicle barrier is prone to tip over, especially if the vehicle climbs up or tends to vault upwardly and over the barrier. To prevent this the barrier 210 is characterized by generally horizontally directed portions defining superposed ribs 35b projecting to a lesser and lesser degree from top to bottom. In addition, a bottom portion 212 of the barrier 210 extends outwardly considerably beyond the ribs 35b to provide a very wide and stable base, the outer face of the bottom portion 12 including a box shape or channel 214 for improved resistance to bending. The configuration of the barrier 210 is designed such that when the barrier 210 is struck at approximately a 90 degree angle by the usual passenger vehicle, the pumper goes over the lowermost portion 212 and impacts and compresses the lowermost, shortest rub 35b. The vehicle hood will go over the lowermost rib 35b, will impact against and compress the next highest rib 35b, and will slide under the topmost rib 35b. The topmost rib 35b thus acts like an overhang to trap the hood and thereby prevent the vehicle from vaulting or leaping the barrier 210. The barrier 210 is prevented from tipping over away from the vehicle by reason of the "hooking" engagement of the portion 212 with the bottom of the vehicle bumper. Energy absorption is provided initially by compression of the lowermost rib 35b by the bumper, the next higher rib 35b by the hood, and the bottom portion 212 by the vehicle tires. As vehicle movement proceeds, the entire barrier aids in absorbing the impact energy. Figures 9 and 10 diagrammatically illustrate filling and emptying arrangements for the barrier section 10 of Figure 1. Figure 9 illustrates a fill cap 24a associated with a conduit 54 extending from the bottom of the barrier section interior chamber to a bladder or overflow container 56 located on top of the barrier section. The container 56 is similar to the previously described bag 92, except that it is normally always externally located. On impact, water forced out of the barrier section fill opening flows into the container 56, from which it can run back down by gravity into the barrier section 10 after the impacting vehicle moves away. Figure 10 illustrates yet another barrier modification, in this case a form of filler cap 24b associated with a pressure line 58 extending from the interior chamber of the barrier section 10 to a pressurized gas bottle 60. The cap 24b is also associated with a conduit 62 which extends to the bottom of the interior chamber of the barrier section 10, and terminates in a usual fire hose 64. In the event an emergency supply of water is necessary for fire fighting, for example, the gas bottle 60 can be actuated to pressurize the barrier section interior and force water out of the fire hose 64. The contained material can be any fluid for the type of fire or other emergency anticipated. Moreover, the fire hose 64 could also be used as a fogging device to provide a protective water spray around the driver of a crashed vehicle. From the foregoing it will be apparent that the present barrier is characterized by great versatility and, most importantly, constitutes a portable, low cost, easily transportable and effective barrier for dissipating the kinetic energy developed upon impact by a moving vehicle. Its unique side wall configuration is effective to reduce the tendency of a vehicle tire to climb up the side wall and vault the vehicle over the barrier. When the side walls of the barrier are struck at a shallow angle, they tend to resiliently yield and hold the vehicle against the wall while speed is lost by "scrubbing" of the tire against the wall, rather than the vehicle ricocheting off and into adjacent traffic or into restricted areas. The barrier of the present invention, in all of its embodiments, is best utilized when the principle of progressive absorption of impact energy is observed. If several of the barrier sections are arranged, end-to-end, or stacked side-by-side, or spaced apart in side-by-side relation, the first of the barrier sections struck by the impacting vehicle should be made capable of deforming or yieldably sliding relatively easily. As previously explained, this can be done by only partially filling it with liquid or other fluent material, or it could be done by not projecting the pins 42 into the pavement or other supporting surface. The barrier section or sections next encountered by the vehicle preferably are filled with liquid to a greater extent, and perhaps the pins 42 projected into the pavement or into receptacles in the pavement. The pins could be made of a cross-sectional thickness and of a material adapted to shear relatively easily. The next barrier section or sections along the vehicle path would be even more completely filled, and perhaps employ pins 42 having an even greater resistance to shearing. In this way the passenger in vehicles striking the barrier would not be subjected to high deceleration forces. The gradual deceleration provided by the barrier brings such forces into a manageable range so that vehicle occupants can survive impacts at relatively high vehicle speeds. An important element in such progressive vehicle decelerations is the yieldability of the barrier structure, and the progressive scrubbing and slowing of the vehicle tire or tires as they push against upper overhanging portions and forwardly located portions dynamically formed in the flexible barrier side walls by the impacting vehicle as it moves along the barrier. The deformed portions present an obstacle constraining the vehicle against vaulting the barrier, and the low coefficient of friction of the barrier material, as well as the presence of traction spoiler channels, reduces the ability of the vehicle tire to develop traction and climb the barrier.

Claims: An energy absorbing barrier comprising a plurality of barrier sections (10) connected end to end, each such barrier section (10) having walls defining a chamber (22) for receiving fluent material (26), said walls including a pair of end walls (16, 18) and a longitudinally directed side wall (20) made of plastic material sufficiently resilient to receive the impact of a moving vehicle to dissipate kinetic energy and resume a normal shape after being struck and deformed by the vehicle, the plastic material having a relatively low coefficient of friction to reduce traction between the side wall (20) and the tire of the impacting vehicle, the side wall (20) being made of a predetermined thickness operative upon impact by a vehicle tire to bulge the side wall material beyond the tire and to propagate the bulged material of the side wall in a travelling wave ahead of the tire to thereby continuously scrub against the tire and slow its advance, and to restrain the tire from climbing and vaulting over the barrier (10), each said barrier section being connected at its ends with the adjoining barrier sections by connection means including protuberances (36) projecting from said end walls (16, 18) and overlying or underlying said complementary protuberances (36) projecting from the adjacent said end walls (16, 18) of the adjoining said barrier sections (10), and further including, at each connection between adjoining barrier sections, a respective vertically oriented connecting pin (42) extended through vertically aligned apertures in the respective overlapping said protuberances, characterized in that, associated with each said barrier section is an elongated strap or bar (86) extending from said connecting pin (42) at one end of the barrier section to said connecting pin (42) at the other end of the barrier section, said strap or bar (86) being coupled with said connecting pins, and thereby with the straps or bars of the adjoining barrier sections, to aid in preventing longitudinal separation of the barrier section (10) upon impact by a vehicle. An energy absorbing barrier according to claim 1 and including a complemental shield (101) overlying the side wall (20) against tearing. An energy absorbing barrier according to claim 1 wherein the barrier is configured to overlie at least one side of a highway median barrier (128, 160). An energy absorbing barrier according to claim 1 wherein the barrier is configured to define a central space for receiving a highway median barrier (128, 160) with side walls (20) disposed on opposite sides of the highway median barrier. An energy absorbing barrier according to claim 1 and including a median barrier attachment fitting (130) at one end of one said barrier section and having vertically aligned and spaced apart protuberances (132) which engage between protuberances (36) projecting from the adjacent end wall of said one barrier section, said one barrier section being connected with said median barrier attachment fitting by a vertically oriented connecting pin extending through vertically aligned apertures in the interfitting protuberances projecting from the median barrier attachment fitting and said one barrier section, the median barrier attachment fitting (130) serving for end coupling the barrier to a highway median barrier (128). An energy absorbing barrier according to claim 1 including an extension barrier disposed on top of said barrier sections (10) defining said chambers (22), said extension barrier comprising a plurality of extension barrier sections (82) each disposed on top of a respective barrier section (10) defining a said chamber, each said extension barrier section having, at its ends, projections having openings extending vertically therethrough in vertical alignment with said openings in the protuberances at the respective end of the respective barrier section (10) upon which the extension barrier section is mounted, the respective said connecting pin (42a) also extending through said openings in the projections of the extension barrier section (82) to support the extension barrier section in position. An energy absorbing barrier according to claim 1 and including a base portion (212) adapted to pass beneath the bumper of a vehicle striking the side wall. An energy absorbing barrier according to claim 1 wherein the side wall (20) is higher than the usual passenger vehicle tire, and includes a portion (190, 35b) projecting outwardly for overlying an impacting tire. An energy absorbing barrier according to claim 1 wherein the end fittings (36, 42) each comprise aligned and interfitting protuberances (36) and intervening recesses (38). An energy absorbing barrier according to claim 1 wherein each said strap or bar (86) has a hole at each end thereof receiving the respective said connecting pin (42), thereby coupling the strap or bar with said connecting pin.

Inventors: THOMPSON, MARION L.
Applicants: ENERGY ABSORPTION SYSTEMS, INC.
Application year: 1987
Main classification: E01F15
IPC codes: E01F15, E01F8