Patent Application
20140010591
1. Technical Field
The invention relates to bollards. In particular, though not exclusively, the invention relates to vehicular impact barriers and bollards suitable for use in vehicular impact barriers.
2. Description of Related Art
The provision of barriers comprising bollards, particularly vehicle barriers, often requires the permanent fixture, embedding or foundation of bollards within a ground surface in order to provide sufficient robustness and resilience of permanency to the barrier. It is very common that bollards arrayed collectively to provide such a barrier on a ground surface require some degree of excavation into that ground surface to enable each individual bollard of the barrier to be firmly, fixedly and permanently set into the ground to be upstanding from it. This is costly, time consuming and damaging to existing ground surfaces. For example an existing ground surface may comprise a paved area or may comprise a floor surface which is not in immediate contact with the ground, such as an elevated floor surface (e.g. a concrete floor) within an upper level of a building such as a car park or airport terminal building or the like. Excavating such a floor surface in order to accommodate embedded bollards is extremely undesirable. Structural integrity maybe compromised and the embedding of suitably robust bollards may not be feasible or permissible.
These problems are compounded when the situation requires only temporary placement of a barrier. In those circumstances, subsequent re-excavation of the embedded bollard members would be required in order to remove the barrier. Subsequent repair of the ground surface or floor surface would be required where excavation had taken place.
Furthermore, when the embedding of barriers within an excavation is required, the existence of obstacles to the intended positioning and linear trajectory of parts of the barrier may prevent the necessary excavation being provided. Additionally, sharp turns in the trajectory of the barrier may be required to avoid obstacles (e.g. street furniture) or to follow a desired arcuate route (e.g. a turn in a pavement).
The present invention aims to provide means and methods which may be used desirably to assist in addressing some or all of the problems identified above, while still providing a robust and effective barrier able to absorb vehicular impact forces efficiently.
According to the present invention there is provided an apparatus and method preferably as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.
In a first of its aspects, the invention may provide a bollard apparatus for use as a vehicle barrier including: one or more bollard members; one or more separate foot members each adapted for ground engagement by placement upon (or shallow-mount embedment within) a ground or floor surface, to each of which is fixed at least one said bollard member upstanding therefrom; at least one collar member positioned within a respective through-opening in a respective foot member wherein the collar member is fixed to the base end of a bollard member and circumscribes the bollard member thereat and wherein the collar member is upstanding from the surface of foot member from which the bollard number is also upstanding. The collar member may be fixed to the base end of a bollard member at its base end. The fixing may be by welding, cementing, adhesion or by the use of fixing members (e.g. rivets, screws, bolts etc), between collar and bollard. Preferably the fixing is substantially permanent.
A collar member may define a bore along which the bollard member is fitted and embraced, wherein the outer diameter of the collar member at parts adjacent the head end of the bore furthest from the through-opening, is less than the outer diameter at parts thereof adjacent the through-opening. Preferably, the outer diameter of parts of the collar member decrease with increasing proximity to the head end thereof progressively, thereby to define a tapering. The diameter of the bore is preferably uniform. The collar member may be solid in construction.
The bollard apparatus may comprise a plurality of such bollard members each bearing a collar member positioned within a respective through-opening in a respective foot. The bollard apparatus may provide a vehicle impact barrier or a part thereof. The invention may be provided as a kit of part for assembly into a bollard apparatus.
The bollard apparatus may include a plurality of bollard members; a plurality of separate foot members each adapted for ground engagement by placement upon (or embedment within) a ground or floor surface, to each of which is fixed at least one said bollard member upstanding therefrom.
Each foot member preferably is adapted to lie across a ground or floor surface to present a relatively large interface area defining a foot print which is significantly greater than the cross-sectional area of any of the bollards attached to the foot member. This enhances frictional ground contact. A foot member may comprise a substantially flat plate, or other flat structure, which extends in directions transverse to the length of the bollard(s) attached to it. A foot member preferably is significantly wider and/or longer than it is thick, i.e. a relatively thin structure such that the foot member presents a minimal vertical height/depth when laid on (or embedded within) the ground.
This aims to minimise the degree of vertical obstruction the foot member presents. A foot member may be shaped to present a substantially rectangular (e.g. square) footprint. Other shapes may be adopted.
A foot member may so extend for a distance less than, or substantially equal to, or exceeding the length of a bollard upstanding from it. In this way, a bollard member may be attached to a transverse foot member which is less wide/long, or is about as wide/long, or is wider/longer than the bollard is tall. The or each bollard member may be attached to an associated foot member at a position upon the foot member such that, at least in one direction, parts of the foot member extend away from one side of the bollard member fixed to it for a distance less than, or substantially matching, or exceeding the upstanding length of that bollard. Each bollard may be longer than the width of the foot member to which it is attached, or each bollard may be shorter than the width of the foot member to which it is attached.
The bollard or bollards attached to a foot member are preferably offset to one side of a surface of the foot member (e.g. a plate). The periphery of the foot member to which the bollard members are closest may be considered to be at the front of the bollard apparatus and the periphery of the foot member furthest from the bollard members can be considered to be at the rear of the bollard apparatus. In use, it is the front of the bollard apparatus which may most desirably be presented in a direction from which vehicular impact is to be expected. Impact forces applied transversely to bollard members at the front of the bollard apparatus may urge the bollard members to tip away from the impacting vehicle, and this tipping movement is at least partly resisted by the parts of the foot member extending towards the back of the bollard apparatus away from the impacting vehicle.
Bollards may be inclined relative to the plane of the foot member to which they are fixed. This may be to take account of inclined ground surfaces such that when the foot member is laid upon it in use, the bollards of that foot member are substantially vertical in orientation. There may be other reasons to incline the bollards relative to their foot member according to design preferences.
Desirably, at least one flexible coupling line may pass from at least one said foot member to at least one other said foot member thereby to couple separate said foot members such that impact forces inducing movement in one coupled foot member are transmissible to another coupled foot member via the at least one flexible coupling line.
Preferably, at least one said flexible coupling line is adapted to be substantially taut in use. Tautness in the coupling line or lines enables substantially immediate transmission of impact forces experienced by any one of the bollard members to be transmitted to other bollard members on other separate foot members when the impact results in movement of a foot member. The foot members may be evenly spaced and bollard members attached to separate foot members may also be evenly spaced. The spacing between successive foot members may be such as to ensure the space between adjacent bollard members of successive foot members matches the spacing between successive bollard members on a given common foot member. Alternatively, the successive foot members may be abutted to each other, side-by-side, or generally as close as is possible whilst still permitting space for coupling lines to pass between foot members as desired.
The bollard apparatus in preferred embodiments may be arranged such that the at least one coupling line extends between opposing edges of neighbouring successive foot members of the bollard apparatus (e.g. from one opposed edge to another edge opposing it). The at least one coupling line may be attached at to each of the foresaid opposing edges. The at least one coupling line preferably comprises two ends (e.g. terminal ends) each one of which is attached to a respective one of the aforementioned opposing edges of neighbouring successive foot members. The at least one coupling line preferably extends between no more than two neighbouring successive such foot members. The at least one coupling line may be attached to two neighbouring successive foot members at respective attachment means (e.g. an attacher(s)). A bollard of one of the foot members is preferably positionable to be spaced from a nearest opposing bollard of a neighbouring foot member along a spacing direction substantially parallel to the direction along which the respective attachment means of a coupling line are concurrently spaced.
The at least one coupling line preferably extends between opposing edges (e.g. straight edges, or otherwise) of neighbouring feet. It is preferably connected (e.g. removeably connected) at its ends to a respective one of the opposing edges. The at least one coupling line may be attached at one end to one foot member and the other end to the other, neighbouring, foot member. In this way the at least one coupling line may be attached at each of its ends to a respective one of two neighbouring foot members. Alternatively, the coupling line may comprise a closed-loop line which loops around attachment means at neighbouring opposing edges of two foot members to couple the two foot members together.
In preferred embodiments, the at least one coupling line extends between only two neighbouring foot members. The bollard apparatus may comprise a succession of a foot member followed by an at least one coupling line attached (e.g. at an end) to an edge of the foot member, there then following a further foot member to which the (e.g. other end of the) at least one coupling line is attached at an opposing edge of the other foot member. Subsequently there may then follow a yet further at least one coupling line attached to a separate edge of the other foot member (e.g. an edge at an opposite end of the other foot member) at, for example, a first end of the yet further at least one coupling line wherein, for example, the second end of the yet further at least one coupling line is attached to an opposing edge of a yet further foot member. This sequence of: foot member—at least one coupling line—foot member, may be repeated as often as desired to generate a barrier comprising a plurality of bollard-bearing foot members mutually coupled by an intervening at least one coupling line passing between (e.g. from and to) opposing edges of neighbouring foot members.
Regarding two separated successive foot members, a bollard member of one given foot member may be positioned upon that foot member to be spaced from a nearest bollard of a neighbouring foot member along a direction, axis or line of separation substantially parallel to the direction of the spacing, axis or line of separation between those places on the two foot members where an at least one coupling line is attached to each of the respective neighbouring foot members. The coupling line(s) may be attached to a foot member by attachment means which link, couple or join the coupling line to the foot member in question. If the coupling line(s) is a chain, or other line terminating with a link, loop, hook or the like, then the attachment means may comprise an eye, eyelet, through-opening, hook or latch into which the termination of the coupling line may link, couple or attach. The attachment means may comprise a pin, rod, bar or shaft mounted or attached to an edge of the foot member in question so as to extend in spaced separation from that edge generally transversely to the direction of the coupling line attached to it (e.g. generally substantially parallel to the edge of the foot member). The spaced separation preferably admits the parts of (e.g. the terminal end of) the coupling line required to form the linkage therewith. The means by which the pin, rod, bar, arm or shaft is so mounted may determine the degree of separation from the edge of the foot member. For example, a conduit or at least one pair of spaced successive conduits may be fixed (e.g. welded) to the edge of the foot member. The conduit(s) may be steel or other suitable metal. The conduits may comprise conduit bores arranged so as to admit and preferably hold parts of the pin, rod, bar, arm or shaft and to concurrently expose a part thereof. Where successive pairs of spaced conduits are employed, the respective conduit bores may be in register coaxially. The parts of the pin, rod, bar, arm or shaft located in the space between the spaced conduits of such a pair is thereby exposed. Consequently, different parts of the same pin, rod, bar, arm or shaft may be held within successive spaced conduits and part of the same pin, rod, bar, arm or shaft extending between successive spaced conduits may be exposed to allow them to attach to a coupling line.
The exposed part of the pin, rod, bar, arm or shaft, together with the conduit (or conduits of a pair) form with the edge of the foot member a means for the coupling line to link to or around to couple to the foot member. The pin, rod, bar, arm or shaft is preferably slidingly removeable and insertable into one, some or all of the conduit bore(s). The attachment means may comprise a plurality of separate (and separable) such pins, rods, bars, arms or shafts which may be insertable and removeable one after the other, or independently, along one some or each conduit. For example, where there are a plurality of spaced conduits, they may be arranged with their conduit axes (e.g. bores, if the conduit is a tube) in coaxial register. A common one pin, rod, bar, arm or shaft may be removeably insertable in common to link multiple coupling lines in tandem to a common edge of a foot member. Alternatively, several shorter pins, rods, bars, arms or shafts may be removeably insertable in succession to form a collinear length along the axially registered conduit bores. Other arrangements for attachments means are possible.
The foot members of a bollard apparatus and the at least one bollard members attached to them are preferably arranged such that opposing edges of the foot parts, when positioned in spaced opposition, are such that the two near most bollards of neighbouring foot members are positionable in register to concurrently place in register those places on the opposing edges of neighbouring foot members at which a (e.g. any or all) given at least one coupling line is attached to mutually couple the neighbouring foot members.
Preferably, the at least one coupling lines are removable attached to, or are adapted to be removable attached to, said opposing edges via attachment means located at each respective opposing edge. Preferably the opposing attachment means associated with an at least one coupling line are mutually laterally offset from the two opposing near most bollards of the neighbouring foot members when those opposing bollards are in register. Preferably, for example, the attachment means associated with at least one coupling line, and attached to opposing edges of neighbouring foot members, are not both located (or positionable to be both located) between the opposing near most neighbouring bollards of the neighbouring foot members. Preferably, the attachment means associated with at least one coupling line are closer to the rear edge of the foot member than to the front edge of the foot member. Note that references herein to the “rear” and “front” of a foot member are synonymous with the front and rear of the bollard apparatus, or barrier unit, as described above and subsequently.
Preferably the attachment means of the opposing edges, associated with a coupling line, are offset towards a rear edge of the respective foot members to which they are attached whereas the opposing near most bollard members are preferably positioned closer to or near most the front edge of each foot member. Preferably each foot member comprises a plurality of attachment means arrayed along an edge of the foot member to form an array adapted to oppose and be positioned in register with a corresponding array of a plurality of attachment means connected to an opposing edge of a neighbouring foot member. The two arrays of attachments means are preferably arranged such that each attachment means of a given one array can be concurrently placed in register with a corresponding respective opposing attachment means when the near most opposing bollard members of the neighbouring foot members are also placed in register. In this way each one of the two attachment means defining one of a plurality of separate pairs of opposing attachment means, as between opposing edges of neighbouring foot members, may be brought into concurrent register when the near most opposing bollards of the neighbouring foot members are also brought into register.
It is preferably that at least one such pair of opposing attachment means is closer to the rear of the bollard assembly while the opposing near most bollard members are closer to the front of the bollard assembly. A second such pair of opposing attachment means may be provided and these are preferably located along the aforementioned opposing edges of the two neighbouring foot members in between the rear most pair of opposing attachment means and the opposing nearest bollard members. Alternatively each one of the second pair of attachment means may be fixed to a respective opposing edge of the pair of neighbouring foot members near most the bollard member attached to that foot member. The result is that when the nearest opposing bollard members are brought into register, so to are the opposing attachment members of the second pair of attachment members in between the two opposing nearest bollard members. Preferably, at least two pairs of opposing attachment means are provided so as to be closer to the rear of the foot members than is a near most bollard of that foot member. The result is that preferably at least one coupling line extends between neighbouring foot members between opposing edges adjacent or nearer to the rear of each foot member than are their associated bollard members. More preferably two such separate coupling lines are attached in this way, and preferably at least a third coupling line couples the opposing edges in the space generally directly between the opposing near most bollards of the neighbouring foot members.
It has been found that when a vehicle impacts a bollard apparatus comprising a coupled pair of neighbouring foot member and bollards, opposing edges of neighbouring foot members tend to be urged to splay such that the separation of those parts of opposing edges towards the rear of the bollard apparatus is urged to be greater than that between the opposing edges towards the front of the apparatus. Attaching a coupling line, or a greater proportion of coupling lines towards to the rear parts of opposing edges has been found to be more effective in resisting and absorbing impact forces. In addition, torque applied by an impacting vehicle to an upstanding bollard member often tends to urge the associated foot member to pivot at its rear most edge in such a way as to lift the front edge (near most the impacted bollard and the impacting vehicle) upwardly. By placing an at least one coupling line between neighbouring foot members towards to the front edge of the bollard apparatus, impact energies conveyed by this torque effect are efficiently transferred laterally from the impacted bollard member to neighbouring foot members and onwardly to any additional foot members subsequently coupled to that neighbouring foot member along the array of the bollard apparatus.
Preferably, the one or more coupling lines are adjustably attached to the attachment means. For example, it/they may be slidingly, rotatably or pivotably attached. The benefit is that when tension is applied to a coupling line it may most preferably be sufficiently self-adjustable to adopt a straight configuration between those parts of the two foot parts between which it extends so as to extend directly. For example, the/a coupling line may be a chain. Each terminal chain link of the chain may have a through-opening through which a rod, pin, arm or bar of the attachment means passes or is arranged to be passed. The attachment means may preferably be dimensioned to admit a terminal chain link attached thereto to pivot about the rod, pin, arm, or bar of the attachment means to which the link is attached, or is arranged to be attached.
Preferably the attachment means is arranged to substantially restrain, restrict or fix the location at which an end(s) of the at least one coupling line is positioned relative to the foot member to which it is attached or arranged to be attached. This may be achieved by providing the attachment means with obstruction parts or portions which prevent movement of the attached end of the coupling line beyond them. For example, an obstruction part(s) may be located upon a said rod, pin, arm, or bar of the attachment means to which the link is attached, or is arranged to be attached to prevent, restrict of restrain movement of the end of the coupling line therealong. The obstruction parts may be provided by said one or more conduits. When there are a plurality of separate spaced conduits, they may preferably be arranged to prevent, restrict of restrain movement of the end of the coupling line in either direction therealong. The benefit of this is that the intended location at which a coupling line is to bear/transmit impact forces imparted to a barrier unit cannot be unintentionally or inadvertently altered.
Desirably, the at least one flexible coupling line is secured to anchor means (e.g. an anchor(s)) adapted to engage said ground or floor surface and to inhibit or restrain movement of the coupling line thereat. The anchor means may comprise one or more anchor members selected from: fixture means (e.g. a fixer(s)) adapted for ground penetration or embedment thereby to provide a fixture thereat; and, weight means (e.g. a weight(s)) adapted for surface placement and comprising a body of weight sufficient to render it substantially immovable manually. An anchor member may comprise a foot member including bollard members. For example, one or each of the terminal foot members in a bollard apparatus may be dimensioned to be significantly larger and heavier than other foot members within the bollard apparatus so as to much more significantly resist movement by virtue of its significantly greater inertial mass and frictional interface with the ground or floor surface upon which it is placed. The bollard members and foot members of a bollard apparatus may be formed from steel and a bollard apparatus may weigh several tons. The benefit of generally restraining movement, more particularly at terminal foot members of a bollard apparatus, is to promote a circumstance in which movement, resulting from vehicular impact, of intermediate foot members in a vehicle barrier induces a tensile stretching of the coupling line(s) resulting from initial movement of impacted (and coupled) foot members—because the terminal ends of the coupling lines move little or mot at all—thereby to effectively absorb and disperse impact forces. This is particularly so when the terminal ends of a coupling line are secured to the terminal foot members. Alternatively, the coupling lines may be secured to separate ground-penetrating or embedded fixtures such as posts, bolts or other rigidly ground-fixed elements which provide for the immobility of the ends of the coupling line(s). Where terminal foot members are not used as anchor means, other large and weighty masses may be employed such as concrete blocks which may weigh at least one or several tons.
Preferably, the at least one flexible coupling line forms along portions thereof a sliding interface with foot members coupled thereby so as to permit relative movement therebetween. This sliding interface preferably permits elastic or tensile stretching in the coupling line in response to impact forces imposed upon the vehicle barrier which assists in absorbing and dislocating impact energies without impeded by points of fixture between the terminal ends of the coupling line. Any such points of fixture may otherwise serve as a high stress point where cable snap or breakage or damage may be more likely to occur than is the case where sliding movement is permitted. This sliding movement also enables sliding movement of foot members either linearly or in a twisting fashion across the ground or floor surface in response to impact forces which in turn pulls or pushes at the coupling line(s) transversely to the line so as to subsequently transversely pull, push or rotate neighbouring coupled foot members of the barrier.
A coupling line may be arranged to pass along and between each said foot member coupled thereby to one side of all bollards of the coupled foot members without passing between those bollards. For example, a coupling line may pass only along the rear of a barrier along those edges of the foot members of the barrier furthest from the bollards of the barrier. This provides a line against which any impacted bollard member, and attached foot member, will be pushed when impacted by a vehicle at the front of the barrier. The taut coupling line may resist this pushing motion and serve to restrain further such pushed movement. It may also effectively act to induce a pivoting or tippling movement of the impacted foot member around the edge of the foot member engaging the coupling line. The result may be a tendency of the pivoted foot member to dig into the ground surface at that pivoting edge to much more significantly resist further sliding movement. Alternatively or additionally, a coupling line may pass along the front of a barrier in order to assist in retaining the multiple foot members of the barrier assembly in their required positions.
A coupling line may be arranged to pass along successive said foot members coupled thereby at opposite successive sides of the bollards of successive of the coupled foot members, passing between bollards. Such a serpentine or slalom pass of a coupling line between foot members helps not only to transfer any transverse pushing movement of one foot member into a transverse pulling movement against neighbouring foot members, but also may serve to translate a rotation of one foot member into an oppositely-directed rotation in neighbouring foot members. This is particularly effective in transferring transverse impact forces laterally along the length of the barrier.
A foot member may preferably extend in a direction transverse to the bollards fixed thereto from a proximal edge to a distal edge further from the bollards than is the proximal edge. A coupling line may extend along said proximal edge. Alternatively, or additionally, a coupling line extends along said distal edge. Alternatively, or additionally, a coupling line extends alternately along a said proximal edge and a said distal edge in alternating succession along successive said foot members. The bollards are preferably upstanding from the foot member between said proximal and distal edges.
The bollard apparatus may include connector means (e.g. a connector(s)) at or adjacent the distal edge adapted to engage with the foot member thereat, the connector means being arranged concurrently to engage said ground or floor surface to connect the foot member thereto. For example, one or more bolts, pins, posts or other ground penetrating, or ground embedding, elements may be used. These elements may impede, or to some extent resist or obstruct sliding movement of the foot member with which they engage. Relatively small and modest ground-penetrating elements have been found to be very effective in retaining a bollard apparatus and barrier in place during an impact event, thus greatly reducing ground disturbance or damage. Much impact energy tends to be dissipated along the barrier due to the coupling line(s) and foot members, leaving much less energy acting against the connector means. The bollard apparatus may include connector means adapted to engage with one some or each said foot member and concurrently to engage said ground or floor surface to connect the foot member thereto.
Preferably, successive of the separate foot members are separated by a space, physical separation or gap. Alternatively, foot members may be abutted in a side-by-side arrangement. One or more coupling lies may pass directly, or diagonally, across the spaces as they pass from one foot member to another. The bollard apparatus may comprise at least three separate foot members, mutually coupled by coupling lines. The terminal foot members may provide anchorages for the ends of the coupling lines. They may be much heavier than the individual intermediate foot member(s) and bollards so as to be more resistant to impact-induced movement.
Each foot member of the bollard apparatus preferably includes guide means (e.g. a guider(s)) adapted to determine or define the direction of travel of a said coupling line along the foot member and through or along which a said flexible coupling line passes. The guide means may include one or more conduits, ducts, pipes, tubes, loops, hoops, channels or grooves on the foot member for guiding one or more coupling lines along/through it.
The bollard apparatus may include shock absorber means (e.g. an absorber(s)) coupled to at least one flexible coupling line and adapted to absorb energy generated by tensile shock loads/forces applied along a coupling line. The shock absorber means may be a compressible structure (e.g. a crumple zone, a resiliently deformable structure such as rubber or elastic material, or a pneumatic element) adapted to compress to absorb shock loads applied to a coupling line.
One, some or each foot member may comprise a structure (e.g. a plate part) presenting a surface upper most in use, which is arranged to admit said at least one bollard member. The structure may comprise a through-opening through which a bollard passes from a lowermost side to and beyond the uppermost surface, in use. The bollard(s) may be welded in this through-opening, e.g. at the periphery of the through-opening desirably at both sides of the foot member. The bollard(s) may stand substantially perpendicularly to a foot member, or may be inclined thereto. Optionally, only one, or at least two bollard members are fixed to each separate foot member.
Preferably, the plurality of separate foot members forms an array in which each foot member is coupled to each other foot member by at least one common flexible coupling line. This maximises dissipation of impact energies by more effectively allowing it to propagate along the whole length of a barrier.
Preferably, the plurality of separate of foot members form an array the terminal foot members of which comprise more bollard members fixed thereto than are fixed to foot members intermediate the terminal foot members. The intermediate foot members may be smaller (e.g. of less length, size and/or weight). The terminal foot members may provide anchorages for the ends of the coupling lines. They may be much heavier than the individual intermediate foot member(s) and bollards so as to be more resistant to impact-induced movement.
The plurality of separate foot members may form an array of successive separate foot members uniformly spaced. The bollard members of the array may be also uniformly spaced.
Preferably, one, some or each separate foot member is formed from steel. Preferably, one, some of each at least one bollard member comprises a steel tube. Preferably, the at least one flexible coupling line is stretchable to dissipate energy transferred thereto by movement of foot members coupled thereby. Preferably, the at least one flexible coupling line comprises a cable or a wire or a chain or a rope or a cord, or any combination thereof. Preferably, the at least one flexible coupling line comprises steel cable, or a plurality of steel cables. Preferably, the at least one (e.g. each) coupling line is adapted to accept a shock load of up to 20 tons, or alternatively, within the range equal to or greater than 20 tons. For example the shock loading capacity of a (the) coupling line(s) may be in a range up to 1 ton, or up to 5 tons, up to 10 tons, or up to 15 tons, or up to 25 tons, up to 30 tons, or up to 50, or 100 tons. The appropriate choice may be made according to preference, for example, taking account of the number of coupling lines, the geometry of the coupling lines (paths) and the speed and weight of a vehicle a barrier is intended to resist. The nominal cross sectional diameter of the material of the coupling chains is about 16 mm but may preferably be between about 10 mm and 20 mm. Preferably the pitch of the links within a chain is about 48 mm, but may preferably be within the range of about 30 mm to 70 mm. The load capacity of each coupling chain is preferably between 5 tons and 15 tons and most preferably 10 tons or thereabouts. The breaking force of each coupling chain is preferably about 400 kN and is most preferably within the range of about 350 kN to 450 kN.
Where a coupling line comprises a chain, the chain may be one manufactured according to ISO 9001 standards. For example, a chain classified to standard OASTM A973/A973M-01 or EN818-2 may be used. The stress at loading capacity of a chain may be between about 150 N/mm2 and 350 Nmm2, such as 250 N/mm2. The breaking stress of a chain may be between about 600 N/mm2 and 1400 N/mm2. The break elongation minimum of a chain may be between about 10% and 30%, or preferably between about 15% and 25%, such as about 20%.
It is intended that the invention may be sold in unassembled form, for assembly into the bollard assembly described above. In a second of its aspects, the invention may provide a kit of parts for a bollard apparatus as described above.
For example, the invention may provide a kit of parts for a bollard assembly for use, when assembled, as a vehicle barrier including: one or more bollard members; one or more separate foot members each adapted for ground engagement by placement upon (or shallow-mount embedment within) a ground or floor surface, to each of which at least one said bollard member is adapted to be fixed to be upstanding therefrom; at least one collar member adapted to be positioned within a respective through-opening in a respective foot member wherein the collar member is adapted to be fixed to the base end of a bollard member to circumscribe the bollard member thereat and wherein the collar member is adapted to be positioned upstanding from the surface of foot member from which the bollard number is also upstanding.
The kit may further comprise a plurality of bollard members; a plurality of separate foot members each adapted for ground engagement by placement upon a ground or floor surface wherein each foot member is adapted to have fixed thereto at least one said bollard member upstanding therefrom; at least one flexible coupling line adapted to pass from at least one said foot member to at least one other said foot member thereby to couple separate said foot members such that impact forces inducing movement in one coupled foot member are transmissible to another coupled foot member via the at least one flexible coupling line when so coupled.
The invention may provide a vehicle impact barrier comprising the bollard apparatus according to any preceding claim.
The invention may provide a method of assembling a vehicle barrier including: providing a plurality of separate foot members each adapted for ground engagement/embedment by placement upon a ground or floor surface (or an excavation therein), to each of which is fixed at least one bollard member upstanding therefrom with at least one collar member positioned within a respective through-opening in a respective foot member wherein the collar member is fixed to the base end of a bollard member and circumscribes the bollard member thereat and wherein the collar member is upstanding from the surface of foot member from which the bollard number is also upstanding; placing said plurality of separate foot members upon a ground or floor surface to form an array of separated such foot members
The method may further comprise providing a flexible coupling line and passing the coupling line from at least one said foot member to at least one other said foot member thereby to couple separate said foot members such that impact forces inducing movement in one coupled foot member are transmissible to another coupled foot member via the at least one flexible coupling line.
The barrier apparatus, when comprising chains as the coupling line(s), may include a shock absorber apparatus comprising a compressible bearing member adapted and arranged for removable insertion between opposing bearing surfaces of successive connected links of a chain. The shock absorber may be use with a chain in order to permit the chain to absorb tensile shocks applied to it in use by virtue of the compressibility of the bearing member. This has been found to reduce the likelihood of breakage between chain links when the chain is subjected to longitudinal/tensile shock loading. A consequence of employing such shock absorber apparatus is that when a chain in question is intended to be used in circumstances where shock loads will occur, the shock-loading capacity rating of the chain need not be as high as would otherwise be required were the shock absorber(s) not employed. Or put another way, the shock-loading capacity rating of a chain may be increased when such shock absorbing apparatus is used.
Furthermore, such shock absorber apparatus may be employed to shorten the fully-extended length of a piece of chain. That is to say, by inserting the shock absorber apparatus in between neighbouring chain links, the result is to separate those opposing bearing surfaces which would otherwise be in direct contact (i.e. bearing against each other) when the chain is fully extended. Consequently, the neighbouring chain links are drawn further together. This shortens the overall length of the chain they are a part of. This is especially useful when fine adjustment of the overall length of a chain (measured when taught) is required, and when a length reduction is required less than that which would result from removing a terminal chain link.
The shock absorber apparatus preferably comprises one or more retention parts or portions separate from the bearing member and adapted and arranged (e.g. shaped) to engage at least one of the connected links at other than a said opposing bearing surfaces thereby to obstruct movement of the bearing member away from a position between the opposing bearing surfaces of the connected links when the bearing member is so positioned thereby to retain that position. For example, a retention part may be arranged to engage with a part of a chain link which is not within the loop or through-opening of that link, and preferably not within the loop or through-opening of either of the two connected links when the chain is fully extended. The shock absorber apparatus may comprise shaped surface parts adapted to correspond reciprocally with (i.e. in sympathy with) the shape of the surfaces (e.g. bearing surfaces) of the neighbouring chain links to permit an intimate interface therebetween in use. This helps retain the shock-absorber apparatus in place and also assists in the transfer of shock loads from a chain link to the shock absorber apparatus. A reciprocally shaped surface part may be saddle-shaped in form. For example it may define a generally concave profile in cross-section in a first plane (e.g. viewed at one side) and a generally convex profile when viewed in second cross-section perpendicular to and intersecting the first plane (e.g. viewed from above or below). This surface is most preferably in sympathy with the surfaces, preferably the bearing surfaces, of typical chain link forms. The bearing member may present two such reciprocally shaped and oppositely outwardly facing (not opposing) surface parts located at opposite ends of the bearing member. Each such surface is preferably shaped for abutment to a respective one of two opposing bearing parts of two neighbouring chain links concurrently.
The, or each, retention part may present at least one concave contact surface shaped to reciprocate outwardly-facing surface parts of a chain link which are not bearing surfaces and are not within, nor define, the through-opening of a chain link. Preferably two such concave contact surfaces are presented at opposite sides of the bearing member to interface with opposite parts of the loop of a chain link concurrently while the bearing member is located between opposing bearing surfaces of successive chain links.
The bearing member may comprise a shaft, rod, arm, pin or tube or the like which may be elongate in a curved or substantially straight manner. A retention part may be greater in diameter of size than is the thickness of the bearing member to which it is attached. For example, a retention part may comprise a bolus, cone, bulb, block of other expansion of the apparatus at or towards one of each terminal end thereof. Preferably a retention part is compressible (e.g. hollow) to reduce its lateral dimension to assist easier manual insertion and removal of the shock absorber apparatus from between successive chain links.
The shock absorber apparatus, or at least the bearing member thereof, may be formed from a resilient rubber or polymer material having a Shore Hardness of at least 50, and preferably at least 60 and more preferably at least 70 and yet more preferably at least 80. Alternatively, the bearing member may comprise a metal tube (e.g. steel) designed to crush or collapse laterally (i.e. in a direction across the bore of the tube) when subject to sufficiently high lateral forces via said opposing bearing surfaces of neighbouring chain links. The transverse width/diameter of the bearing member may be a value between about 5 mm and about 10 mm. Thus, each insertion of a shock absorbing apparatus in between chain links of a fully extended chain may thereby reduce the length of that chain by the same a value between about 5 mm and about 10 mm.
In another of its aspects, the invention may provide a bollard apparatus for use as a vehicle barrier comprising: one or more bollard members; a plurality of separate foot assemblies each adapted for ground engagement by placement upon, or embedment within, a ground or floor surface, to at least one of which is fixed at least one said bollard member upstanding therefrom; and each said foot assembly comprises a pair of opposed parallel plates separated by a plurality of coupling beams which are each fixed to both of the opposed plates and are sandwiched therebetween; wherein a pair of said coupling beams extend in parallel adjacent an edge of a foot assembly of the plurality of foot assemblies and define between them an a spacing accessible at said edge and adapted for receiving an end of a separate coupling beam extending adjacent an edge of a separate other said foot assembly; and a linkage member for linking each of said pair of coupling beams to an end of said separate coupling beam when so received thereby to couple the two foot assemblies.
Each coupling beam may comprise a through-opening and the linkage means (e.g. a linker(s)) may comprise a pin member adapted to extend concurrently through the through-openings of each of the coupling beams of the pair of coupling beams and of the separate coupling beam when so received.
Each foot assembly may comprise an aforesaid pair of coupling beams extending adjacent an edge thereof, and an aforesaid separate coupling beam extending adjacent a separate edge thereof.
Each foot assembly may comprise two separate aforesaid pairs of coupling beams extending adjacent a common edge thereof, and two aforesaid separate coupling beams extending adjacent a common separate edge thereof.
The bollard apparatus may comprise a foot assembly in which the coupling beams of the two separate said pairs of coupling beams are substantially mutually parallel, and the aforesaid two separate coupling beams are substantially mutually parallel.
The coupling beams of the aforesaid two separate pairs of coupling beams may extend in a direction oblique relative to the direction in which the aforesaid two separate coupling beams extend. This enables successive foot assemblies to be coupled in a non-linear (arcuate) array or path. Alternatively, or additionally, the coupling beams of the aforesaid two separate pairs of coupling beams may extend in a direction substantially parallel to the direction in which the aforesaid two separate coupling beams extend. This enables successive foot assemblies to be coupled in a linear array or path. The apparatus may comprise a mixture of foot assemblies enabling of these two types enabling linear and non-linear parts in an array of coupled foot assemblies forming a barrier.
In some embodiments, one of the pair of opposed plates of a foot assembly uppermost in use defines a through-opening through which a bollard member extends from within the space between the opposed plates so as to be upstanding from the surface of foot assembly uppermost in use.
A collar member may be fixed to the base end of at least one bollard member, and may circumscribe the bollard member thereat. The collar member may be positioned within the through-opening to be upstanding from the surface of foot assembly from which the bollard member is also upstanding.
Such a collar member may define a bore along which the bollard member is fitted. The outer diameter of the collar member at parts adjacent the head end of the bore (i.e. the parts furthest from the through-opening) may be less than the outer diameter at parts thereof adjacent the through-opening. This defines a tapering having the advantages described above.
The collar member may have the structure described above in respect of other aspects of the invention, and may be fixed to the foot assembly as described in any embodiment herein.
The bollard apparatus may define of vehicle impact barrier or a part thereof, e.g. comprising a plurality of coupled foot assemblies each comprising one or more bollards.
For a better understanding of the invention, and to show how example embodiments may be carried into effect, reference will now be made to the accompanying drawings in which:
In the drawings like articles are assigned like reference symbols. The barriers of the following examples may be surface-mounted shallow-mounted in a shallow excavation within which a foot part is embedded.
Each of four flexible coupling lines (202,203,204,205) separately comprises a length of steel cable secured at both of its terminal ends to a respective one of two anchorage assemblies, in the form of anchorage posts. Each coupling line extends from a first one of the two anchor assemblies and travels away from that anchor assembly by passing successively along one of the two long, peripheral, rectangle edges of the plate parts of each successive foot member of the four barrier units of the barrier assembly before reaching the short, peripheral, rectangle edge of the plate part (4,7) of the foot member of the other terminal barrier unit, that being the edge which is furthest from the anchorage post to which the coupling line is anchored, and which defines a terminal end of the barrier. The given coupling line then extends from other terminal barrier unit and back towards the second anchorage post to which it is anchored.
Thus, the terminal ends of each one of the four coupling lines are secured to a respective one of the two anchorage posts (200,201) at the ends of the barrier. The result is that each coupling line originates from an anchorage post and passes to each foot member of the barrier assembly. In this way, each of the coupling lines passes from each one of the separate foot members of the barrier units, to each one of the other separate foot members of the other barrier units. The result is that each separate foot member is coupled by the coupling lines, separately, to each one of the other foot members of the barrier.
The foot member of each of the barrier units extends in a direction transverse to the two or more tubular bollards fixed to it, from a proximal edge of the foot member which is closest to the bollards and extends in front of each of them, to a distal edge which is parallel to the proximal edge but which is further from the bollards than is the proximal edge. The proximal and distal edges are parallel and are defined by the long, peripheral, rectangle edges of the plate of a foot member. The bollards of a given barrier unit are located between the proximal and distal edges, in a linear array parallel to, and uniformly offset from, each of the proximal and distal edges. The bollard array is closest to the proximal edge. The proximal edge of the plate part of a given barrier unit is positioned in register with the proximal edge of the plate part of each neighbouring barrier unit. The result is that the distal edge of the plate part, and the bollards, of a given barrier unit is also positioned in register with the distal edge of the plate part, and the bollards, of each neighbouring barrier unit.
Each foot member includes a proximal guide conduit (19) and a distal guide conduit (20) each comprising a linear elongate box-section tube, having a pair of opposing parallel, upper and lower, walls separated by a pair of parallel side walls joining them. These four conduit walls define a square-shaped cross-sectional shape uniformly along the length of the guide conduit. One of the side walls is joined, e.g. by welding, along its outer length to substantially the whole length of a long, peripheral, rectangle edge of the plate part of the foot member of a barrier unit. This defines the guide conduit as an elongate duct or tube open only at opposite ends of the conduit and dimensioned to admit two coupling lines along and through it. The conduits may be formed from steel or other metal. Each of the long, peripheral, rectangle edges of the plate part of each of the barrier units possesses such a guide conduit.
The proximal guide conduit (19) extends along the proximal edge of the plate part of each of the foot members and retains the coupling lines in register with the proximal edge as they pass through the respective guide conduit. Similarly, a distal guide conduit (20) extends along the distal edge of the plate part of each of the foot members and retains each of the two coupling lines which pass through it in register with the distal edge.
The barrier comprises a first, second, third and fourth barrier units (304 to 307) and two terminal anchorage posts (200, 201) to which the terminal ends of each of four coupling lines (202, 203, 204, 205) are attached. The anchorage posts comprise ground-penetrating posts (200, 201) which are each fixed to (e.g. firmly embedded in) and upstanding from the ground or floor surface (21) upon which the barrier resides, adjacent to opposite terminal ends of the barrier.
A first coupling line (202) of the barrier of
A second coupling line (203) of the barrier of
A third coupling line (204) of the barrier of
A fourth coupling line (205) of the barrier of
In an alternative, the fourth coupling line may be omitted. In an alternative, the second sand third coupling line may be omitted instead or as well.
The invention in any of the embodiments described above, or otherwise, may comprise only a coupling line (or lines) which passes along the distal edges and guide conduits of the barrier units of the barrier without passing along a proximal edge. The invention in any of the embodiments described above, or otherwise, may comprise only coupling line(s) which each pass alternately along the distal edges and proximal edges, through successive distal and proximal guide conduits of the barrier units of the barrier, collectively passing along each such edge of the barrier units of the barrier following a serpentine route. The invention in any of the embodiments described above, or otherwise, may comprise a coupling line (or lines) which passes along the distal edges and guide conduits of the barrier units of the barrier without passing along a proximal edge, together with a coupling line(s) which passes alternately along the distal edges and proximal edges, through successive distal and proximal guide conduits of the barrier units of the barrier, collectively passing along each such edge of the barrier units of the barrier by following a serpentine route. The invention in any of the embodiments described above, or otherwise, may omit any coupling line which passes along a proximal edge and proximal guide conduit of the barrier units of the barrier.
The linear route travelled by the first coupling line along the distal edges of the barrier units serves to restrain movement of the barrier units in the direction towards the distal edges. The energy of impact is dissipated by this—such a movement being transferred along the coupling line towards other barrier units. The serpentine route travelled by the third and fourth coupling lines along the array of barrier units of the barrier serves to transfer a rotation/twisting movement of one barrier unit to a neighbouring barrier unit, which is urged by the first coupling line to rotate on the opposite sense. In particular, a corner of a foot part at a distal edge of the plate part of a barrier unit is coupled by a coupling line to a diagonally opposite corner of a foot part at a proximal edge of the plate part of a neighbouring barrier unit. A twisting movement of a barrier unit to move the distal corner in a direction away from the diagonally opposed proximal corner causes a coupling line to pull the proximal corner generally towards the displaced distal corner. This dissipates the impact energies along the barrier array and transforms linear vehicular motion/energy into rotational energy along the separate barrier units of the vehicle impact barrier (1). Furthermore, the second coupling line passing along proximal edges of barrier units assists in impeding the upward pivoting/tippling of a proximal edge when the bollards of that barrier unit are impacted. This is because, the impacted barrier unit is urged back down towards the ground surface by the weight of the rest of the barrier units to which it is coupled at their respective proximal edges by the second coupling line.
Tautness in the coupling lines maximises the effectiveness of these coupling interactions. Transverse deviations in the geometry arrangement of the array of barrier units in the barrier in its quiescent state, with coupling lines taut, tends to pull on one or more coupling lines which thereby resist such deviation, as does the inertial mass of the barrier units and their frictional interface with the local ground surface.
The bollards of the four barrier units collectively define the front of the barrier to be positioned, in use, towards the direction from which impacting vehicles are expected. The distal edges of the four barrier units collectively define the back of the barrier to be positioned, in use, away from the direction from which impacting vehicles are expected. When impact occurs at the front of the barrier, the impacted barrier unit(s) receive an impact force along their vertical length and predominantly concentrated around the upper end of the impacted bollard(s). This impact force urges the impacted bollard(s) to pivot about their base, which is fixed to the foot part of the barrier unit(s) in question. In turn, the respective foot part is urged to pivot upwardly about its distal edge which engages the ground or floor surface upon which the barrier is arrayed. This serves to concentrate impact forces at the distal edge which tends to dig in to, or gouge, the ground or floor surface thereby greatly increasing resistance to movement of the barrier unit.
By coupling together neighbouring barrier units by passing the first coupling line (17) along the distal edges of each of the barrier units in succession, a fulcrum is provided against which a foot member may urge and pivot, at least temporarily during an impact event, to assist or induce this pivoting movement about the distal edges in response to impact forces at the proximal edges of a barrier unit. The fulcrum effect of the first coupling line is to “trip-up” the impacted barrier unit at its distal edge.
Pins, bolts or other ground-penetrating members (not shown) may be arrayed along the distal edges and fixedly entered into the ground/floor surface there to provide an additional fulcrum point against which a foot member may urge and pivot, at least temporarily during an impact event, to assist or induce this pivoting movement about the distal edges in response to impact forces at the proximal edges of a barrier unit. The ground-penetrating members may be arrayed adjacent to the distal edge of a barrier member without passing through the plate part of the barrier member, thereby simply providing a fixed obstacle to sliding movement of the barrier members over the location of the ground-penetrating member. Alternatively, the ground-penetrating members may be arrayed adjacent to the distal edge of a barrier member by passing through apertures (not shown) formed through the plate part of the barrier members.
Each one of two coupling lines in maintained substantially taut. This is achieved by selecting an appropriate length of coupling line according to the separations between, and dimensions of the successive foot members of the barrier array. Each flexible coupling line is fixed to an anchorage post only at the terminal ends of the coupling line such that all sections of a coupling line between its terminal ends is able to slidingly interface with those surfaces of the foot members with which it makes contact. This sliding interface permits movement between the taut coupling line and the foot members coupled by it. The tautness of the coupling line is maintained by its anchorage to the anchorage posts.
Each coupling line is preferably steel cable or wire rope approximately 30 mm in diameter (e.g. from 26 mm to 35 mm), though other diameters may be used. Chain may be used. This may provide a minimum breaking strength of the coupling line of between about 450 kN and 600 kN. The minimum breaking strength of a coupling line maybe determined as the minimum applying a straight-line pulling force that will break the line when both ends of the line are fixed to prevent their rotation, as will be readily understood by the skilled person. One or each coupling line may comprise a plurality of separate coupling sub-lines acting in together to as one coupling line following a common route within the barrier and anchored to common anchorages, which collectively provide the requirements described above.
Vehicular impact forces to which the barrier may be subjected may commence with a sharp impulse force of about 250 ms duration, or thereabouts, as high impact energies are initially imparted to the barrier from the impacting vehicle. The impacting vehicle may be a lorry/truck weighing about 7.5 tons travelling at about 50 kilometres per hour (about 30 mph), for example. The impulse force generated by the initial impact of such a vehicle will result in a high shock load along the axial length of coupling lines of the barrier as the barrier units within it move (twist/translate) to some degree in response. The ability of the coupling lines to remain integral and functional during this initial impulse period is important not only in maintaining the integrity of the barrier but also in effectively dispersing localised impact energies along the length of the barrier. Each coupling line preferably supports a shock load in the range from about 20 tons to about 40 tons, or more, for this reason.
The shock load supportable by a line may be calculated according to the following formula:
Where Pf is the shock load applied, without line failure, to a line of length l when the static load P, attached to one end of the line, is dropped through a height h with the other end of the line fixed at a fixture point above the drop point. The line has cross-sectional area A (e.g. metallic area of a wire rope), and a modulus of elasticity E. Upon dropping the static load, stress is applied to the line when it is pulled to its full, un-stretched, length by the falling load, and is subsequently stretched by the rapidly applied (shock) load incurred as the falling load P is decelerated by the taut line to the end of which it is attached.
The thickness of the steel plate of the plate part of the foot member of each barrier unit may be between 200 mm and 500 mm, such as about 400 mm (or thereabouts). The length of each short rectangle edges of the steel plate may be between 1 m and 2 m, e.g. about 1.5 m (or thereabouts). The length of each long rectangle edge s of the steel plate may be between 1 m and 6 m, e.g. about 2 m (or thereabouts) for smaller barrier units (e.g. comprising two bollards), e.g. about 5 m (or thereabouts) for larger terminal barrier units (e.g. comprising four bollards). Bollards may be between about 0.5 m and 2 m in length, typically about 1 m or thereabouts.
One, some or each bollard (15) may comprise a tube welded at its base to a respective foot plate of a barrier unit, or may most preferably comprise an upstanding collar member (15B) attached to the base of a bollard tube (15A) by welding, the collar being welded to the respective footplate thereby to indirectly connect the bollard tube to the foot plate. Barrier units may have very substantial inertial mass as a result which renders them difficult to move by impact forces of the type described above, especially the larger terminal barrier units.
Referring to
In particular, three separate barrier units (401, 402, 403) are arranged in a linear array such that each of the two bollards (15) of a given barrier unit are aligned in register with those of each of the other barrier units to form a linear array of evenly-spaced bollards. More such barrier units may be used in the array. Each of the barrier units comprises a rectangular plate part having a proximal rectangle edge near most the bollards carried by the given barrier unit and a parallel distal rectangle edge furthest from those bollards. These proximal and distal rectangle edges are separated by two shorter rectangle edges at opposite sides of a given barrier unit.
Welded along each of the two side edges of a given barrier unit is an array of evenly spaced and commonly sized/dimensioned steel tube elements (413 to 421;
A substantially identical array of nine coupling tubes (other than nine may be employed) is similarly fixed and arranged to the opposing and parallel rectangle side edge of a neighbouring bollard assembly, or to the opposing parallel edge of a neighbouring anchor plate (500) adapted to be pinned and bolted or otherwise fixed to a ground surface through holes passing through the surface-engaging plate (500) of the terminal anchor.
For example
Opposing such linear arrays of coupling tubes, and the intermediate spacings between them are thereby able to be placed in register with one another when the bollards of neighbouring barrier assemblies are also arranged in register in a linear array.
The outer diameter of each coupling tube exceeds the inner diameter of the through-bore of the coupling tube by an amount which substantially matches or exceeds slightly the thickness of the terminal chain link through which the common coupling pin passes. This permits the terminal chain link to pivot or rotate about the common coupling pin in order to avoid stiffness, stress or strain on the coupling pin and to allow the flexible coupling chain lengths to be pulled taut into a generally straight configuration without applying talk to the coupling pin.
The coupling pin (or each of a plurality of shorter pins) is slidingly removable from the array of nine coupling tubes by application of a pulling or pushing force axially along the coupling pin and applied at one of the two exposed terminal ends of the pin in situ.
That is to say, the length of the common coupling pin (or the combined length of multiple shorter pin lengths in a line) exceeds the distance between the extreme terminal ends of the two terminal coupling tubes.
The nominal cross sectional diameter of the material of the coupling chains is about 16 mm but may preferably be between about 10 mm and 20 mm. Preferably the pitch of the links within a chain is about 48 mm, but may preferably be within the range of about 30 mm to 70 mm. The load capacity of each coupling chain is preferably between 5 tons and 15 tons and most preferably 10 tons or thereabouts. The breaking force of each coupling chain is preferably about 400 kN and is most preferably within the range of about 350 kN to 450 kN.
Chains manufactured according to ISO 9001 standards may be used. For example, a chain classified to standard OASTM A973/A973M-01 or EN818-2 may be used. The stress at loading capacity of a chain may be between about 150 N/mm2 and 350 Nmm2, such as 250 N/mm2. The breaking stress of a chain may be between about 600 N/mm2 and 1400 N/mm2. The break elongation minimum of a chain may be between about 10% and 30%, or preferably between about 15% and 25%, such as about 20%.
The transport carriage comprises a pair of parallel box-section carriage beams (angle-section beams maybe employed alternatively) indicated as items 501. The parallel carriage beams are separated by two spaced transverse beams (505) having a length such that the maximum transverse width of the transport carriage is substantially less than the separation between the opposing external surfaces of the two bollards of the barrier unit (e.g. less than 1.2 meters). Each of the carriage beams (501) has welded to it two lifting tabs (504) positioned adjacent the transverse beams (505) attached thereto. Through-holes pass through each of the lifting tabs and are dimensioned to admit a hook or other support line with which the transport carriage maybe coupled to a lifting mechanism (e.g. a crane, a forklift truck etc) to allow the transport carriage to be lifted together with a barrier assembly attached to it as shall now be described.
Adjacent the terminal ends of each of the two carriage beams (501) of the transport carriage is positioned respective of one of four lifting rods (502) comprising a substantially vertical rod position (502) topped by a transverse section defining a generally “T” handle.
The lowermost terminal end of the lifting rods projects outwardly through the through-openings (506) passing through the upper and lower walls of the box-section carriage beams and terminates with threading adapted to match the internal threading of each one of the four coupling nuts (431) welded to the proximal and distal edges of the foot member (401) illustrated in
The portion of the lifting rod positioned above the internal floor of the box-section carriage beam within the carriage beam, is threaded externally and carries upon it a reciprocally threaded load nut assembly (600) comprising a pair of nuts tightened against each other so as to be substantially firmly positioned upon the shaft of the lifting rod. The terminal end of the lifting rod, and sufficient of the external length of the lifting rod leading up to that terminal end, is externally threaded to permit it to engage with the coupling nut (431) upon the plate part of the barrier unit (401).
The separation between the lowermost surface of the load nut assembly (600) and the terminal threading of the lifting rod exceeds the distance between the uppermost surface of the floor of the box section carriage beam and the threaded opening of the coupling nut (431) welded to the plate part. This separation is determined by the height of the box-section carriage beam above the local ground surface supporting the carriage trolley and the barrier unit. The distance may be adjusted as desired by loosening the tightened pair of nuts of the load nut assembly, repositioning them securing them in their new position by re-tightening them there.
Operation of the lifting rod to lift the barrier unit (401) is as follows. With the load nut assembly separated from the internal floor of the carriage beam, the terminal threading of the lifting rod is inserted into the coupling nut (431) and rotated to engage with the coupling nut. Continued such rotation draws the lifting rod towards the coupling nut and thereby draws the load nut assembly (600) into contact with the upper surface of lower internal floor of the carriage beam (501). Once such contact is made, continued rotation of the lifting rod simply causes the fixed load nut assembly to rotate against the floor of the support bean it abuts without moving axially along the threaded parts of the lifting rod it is fixed to. Consequently, the terminal threading of the lifting rod bears upwardly against the internal threading of the coupling nut to raise the coupling nut along the axis of the lifting rod, and the barrier unit along with it.
When this operation is done in tandem at each of the four lifting rods (502) the whole of the plate part of the barrier unit may be lifted off of the ground and moved by pushing the transport carriage upon its wheels (503) which may be swivel-mounted to their respective support beams (as in a trolley), or by attaching the transport carriage to a lifting device via the four lifting tabs (504).
Each collar member (15B) is attached to the lower portions of a respective bollard tube (15A) near the terminal end thereof nearest the plate part from which both extend. The terminal end of the bollard tube passes fully through the collar member which circumferentially envelops and embraces the curved tubular outer surface parts of the bollard tube located within the collar. A short terminal length (about 20 mm in the axial direction) of the bollard tube projects beyond the base of the collar member within the through-opening. The result is that the final short terminal length of the bollard tube is exposed within the through-opening.
The terminal end surface (700) of the bollard tube is positioned to be flush with the periphery of the through-opening at the underside of the plate part so as not to project from the plate part at the underside. A circular channel is thereby formed between the outer curved tubular surface of the short portion of exposed bollard tube end, and the opposing inner curved surface of the circular through-opening adjacent the surface of the plate part lowermost in use. A continuous first fillet weld (700) is located within this circular channel between the exposed end portion of the bollard and the adjacent base surface of the collar member. This weld fixes the exposed end of the bollard tube to the collar. A second separate continuous circular fillet weld (702) is formed in the circular channel between the base surface of the collar member and the adjacent inner surface of the through-opening (703) of the plate part not covered by the bollard tube. This weld fixes the base surface of the collar member to the inner wall of the through-opening also. Optionally, a third fillet weld (704) may circumscribe the collar member where it is upstanding from the upper surface of the plate part, filling the corner formed thereby with the upper surface to join the collar to the upper surface.
The outer circular diameter of the collar member (15B) matches the inner circular diameter of the through-opening and forms a tight interference fit therewith at substantially all of those external parts of the collar member located opposing the inner wall of the through-opening. The height of the collar member exceeds the thickness of the plate part, by approximately a factor of two and is only partially inserted into the through-opening so as to extend from the through-opening at the same side of the through-opening from which the bollard tube (15A) concurrently extends. As a result, the collar member is upstanding from the surface of the plate part uppermost in use as is the bollard tube which passes through it.
Consequently, lateral forces applied to the bollard during vehicular impact are transmitted to the plate part via the intermediate collar member. The greater surface area of the interface that can be provided between the collar member and the parts of the bollard tube it embraces reduces the pressure at that interface as compared to what would be the case were the collar absent and the bollard tube in direct contact with the through-opening. The bollard is also effectively thicker at the interface with the through-opening by virtue of comprising the bollard tube thickness and the surrounding collar thickness there. This adds to bollard strength where most needed without having to continue that level of thickness along the whole length of the bollard tube, which would render the bollard expensive and heavy. Also, the positioning of the collar member relative to the end of the bollard tube and through-opening wall, to provide a circular channel for receiving welding (700), allows the bollard tube to be welded to the plate part via a minimal portion of its outer tubular surface relatively furthest from the likely point of vehicular impact. It has been found to be advantageous to minimise the application of welds to the outer tubular surface of a bollard tube as they tend to stress the tube and provide points of weakness when the bollard tube is under impact.
The collar member defines an inner bore having a circular diameter dimensioned to match the outer circular diameter of the bollard tube at its base. The outer tubular surface of the bollard at its base end thereby forms an interference fit with the bore of the collar member. The outer circular diameter of the collar member is structured to reduce increasingly towards the head end thereof at parts of the collar member adjacent to the head end, furthest from the through-opening of a foot member. This forms an even tapering of the outer diameter of the collar member. The diameter if the bore of the collar member is uniform along the length of the bore such that the tapering results in a progressive reduction in the thickness of the walls of the bore of the collar member towards its head end.
The collar wall thickness (un-tapered parts) may be between about 20 mm and 50 mm, preferably between 30 mm and 40 mm. Preferably, the collar is made from a mild steel. The collar part may preferably be made from a material more deformable, malleable or less hard than the material of the bollard (e.g. harder steel).
The tapering of the collar member towards its head end provides there a region of relatively increased deformability in the collar member. When this region is subject to vehicular impact forces directed transversely to the axis of the bollard tube, and the bore of the collar member containing the bollard tube, it has a purposely increased tendency to deform relative to the un-tapered parts of the collar member, and in so doing has a much greater capacity to absorb impact energies by the act of deforming in response to them. Such impact forces tend to generate a torque upon the bollard tube acting about a fulcrum formed between the base region of the bollard tube and the bore of the collar member embracing it. This tends to be the region circumscribed by the periphery of the through-opening in the foot part of the barrier unit within which the collar and bollard are mounted. Consequently, energy is imparted into the tapered head end of the collar member significantly by this torque action. This energy may be efficiently absorbed and dissipated into the process of deforming the tapered parts of the collar member rather than shearing or significantly compromising the bollard tube at the head end of the collar member.
This use of a collar member with one, some or all bollards of a barrier unit may be applied to the invention in any and all embodiments.
In particular, a bollard comprises a bollard tube (15A) having a base end (701) inserted into a through-opening in a plate part (4,5,6,7 etc or 401, 402, 403 etc). The base end (701) of the bollard tube is recessed from the peripheral edge of the through-opening at the base surface of the footplate so as to define a corner at the junction between the base surface of the bollard tube and the adjacent inner walls of the through-opening. A continuous circular fillet weld (705) joins the bollard to the plate part at this corner. Optionally, a second continuous circular fillet weld (706) may be formed in the corner defined by the junction between the outer curved surface of the bollard tube and the adjacent uppermost surface parts of the plate part defining the periphery of the through-opening in the plate at that uppermost surface. In this way the second fillet weld joins the bollard tube (15A) to the plate part.
Referring to
For example, a coupling line (chain) nearest the rear of the barrier (800) is shorter than the coupling line (e.g. chain) located nearest the front of the barrier (808) between the same two barrier units. Indeed, the coupling line nearest the front of the barrier is the longest coupling line of the group of eight and all coupling lines between the shortest and the longest are each a respective of one of six different intermediate lengths each of which corresponds to the distance between the opposing edges of the neighbouring barrier units between which they extend. This length differential permits all of the eight coupling lines between neighbouring barrier units to be substantially taut when the successive barrier units are arranged in an arc.
This is to be contrasted with the arrangements described above with reference to
In order to modify the arrangement illustrated in
A first example of a shock absorbing insert is illustrated in schematic form in
In particular,
The terminal ends of the shock absorber insert comprise retention parts (931) formed as expanded terminal portions of the shock absorber insert apparatus. Each is shaped as a circular-conical frustrum expanding, at its narrower end, from the endmost parts of the intermediate circular rod (932) of the insert to its widest conical width at the terminal respective end of the shock absorber apparatus. Each of these two terminal frustrums is hollow and presents a circular cavity opening at its cone base, the cavity being conical and extending into the body of the frustum to define frustum walls of desired width. Consequently, the frustum walls are of a thickness chosen so as to be manually compressable between finger and thumb to allow the wider terminal parts of the frustrum to be squashed or compressed to a certain extent to reduce size to assist in the insertion thereof between the chain link parts when inserting the shock absorber insert.
A linkage pin (1013) is provided for linking each of the pair of coupling beams to an end of a separate coupling beam when so received thereby to couple any one of the foot assemblies of
Each foot assembly of the bollard apparatuses of
The coupling beams of the two separate said pairs of coupling beams (1006,1009) are substantially mutually parallel, and the two separate coupling beams (1011, 1012) are substantially mutually parallel. However, in some foot assemblies, such as in
A barrier may comprise a mixture of such bollard apparatuses having different coupling beam orientations to enable deviations from linearity in the path of the barrier formed from the assemblies.
Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1101513.8 | Jan 2011 | GB | national |
| 1101514.6 | Jan 2011 | GB | national |
| 1104802.2 | Mar 2011 | GB | national |
| 1113211.5 | Aug 2011 | GB | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/GB12/50175 | 1/27/2012 | WO | 00 | 9/20/2013 |
