Fixed bollard system

A fixed bollard system includes a plurality of spaced apart, elongated bollards each longitudinally disposed along a corresponding X-axis, each bollard being comprised of an I-beam having a front face and a opposing back face extending between a top end and an opposing bottom end. A plurality of horizontal support beams are each longitudinally disposed along a corresponding Y-axis, each horizontal support beam being comprised of an I-beam and having a first end and an opposing second end, the first end of each horizontal support beam being connected to the back face of a corresponding bollard at the bottom end thereof. An elongated lateral front beam connects to the front face of each of the plurality of bollard at the bottom ends thereof. An elongated lateral rear beam connects to the second end of each of the plurality of horizontal support beams.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to fixed bollard systems and, more particularly, to fixed bollard systems capable of sustaining a K-12 impact test.

2. The Relevant Technology

Bollards comprise short posts, often used in a series, that are designed for diverting or excluding motor vehicles from a defined area. For example, bollards are increasingly being positioned around federal government buildings, historical sites, and military bases to prevent vehicles from driving into or adjacent to such structures. One conventional type of bollard simply comprises a large metal post that is positioned within a deep hole. The hole is then back filed with rebar and concrete so that only the top of the post projects above the ground surface. The strength of the post, the depth of the post, and the amount of concrete supporting the post are factors determining the size of impact the post or bollard can sustain without failure.

Although such conventional bollards are useful, they have significant drawbacks. For example, it is often desirable to place bollards around a preexisting building or structure. It is often difficult, however, to dig deep holes about a city structure without hitting utility lines such as water lines, gas lines, telephone cables or the like. As a result, such bollards either have a shallow anchor, and thus low impact resistance, or substantial effort must be made to move the utility lines.

In one approach to solving the above problems, bollards have been designed having specially fabricated anchors that connect to the bollards. Although such anchors can have a lower profile, they still typically have a thickness of greater than two feet. Furthermore, the anchors must be specially fabricated, thereby increasing their cost and limiting their applicability.

Another problem with conventional bollards is that they can be very labor intensive to install on-sight.

Accordingly, what is needed are fixed bollard systems that have a low profile design, that can withstand high impacts, that can be manufactured with conventional off-the-shelf parts and/or that have decreased labor requirements for on-sight installation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to fixed bollard systems and, more particularly, fixed bollard systems that are capable of passing a K-12 impact test as defined by the Department of State (“DOS”). In general, to pass a K-12 impact test, the bollard system must be able to stop a 15,000 pound truck moving at a velocity of 50 mph. Further details with regard to the K-12 impact test can be found at “Test Method for Vehicle Crash Testing of Perimeter Barriers and Gates”,Physical Security Division, DOS, SD-STD-02.01, Revision A, March 2003. In alternative embodiments, the fixed bollard systems of the present invention need not be capable of passing a K-12 impact test but can be configured to pass a lower impact test such as a K-8 or K-4 impact test as defined by the DOS.

Depicted inFIG. 1is one embodiment of an inventive fixed bollard system10incorporating features of the present invention. Fixed bollard system10includes a base12and a plurality of spaced apart bollards14upwardly projecting therefrom. As depicted inFIGS. 1 and 2, base12is depicted having a substantially rectangular, parallel piped configuration. Specifically, base12has a top surface16and an opposing bottom surface18that are disposed in substantially parallel planes. Top and bottom surface16and18extend between a front face20and an opposing back face22and also between opposing end faces24and26. In the embodiment depicted, front face20and back face22are disposed in parallel planes while end faces24and26are also disposed in parallel planes. In alternative embodiments, however, it is appreciated that the opposing surfaces and faces need not be disposed in opposing parallel planes but can be disposed in intersecting planes or the opposing surfaces and faces can be irregular or contoured.

Base12has a height H1extending between surfaces16and18that is typically in a range between about 15 inches to about 21 inches, with about 17 inches to about 19 inches being common and about 18 inches being most common. Other heights can also be used. Base12has a width W1extending between faces20and22that is typically in a range between about 6 feet to about 7 feet, with about 6.25 feet to about 6.75 feet being common, and about 6.5 feet being most common. Other widths can also be used. In the illustrated example, base12has a length L1extending between faces24and26in a range between about 20 feet to about 30 feet, with about 22 feet to about 26 feet being more common and about 24 feet being most common. It is appreciated that the length L1can be any desired length and is based solely upon the amount of territory to be protected by fixed bollard system10.

Bollards14upwardly project from top surface16of base12so as to project orthogonal to base12. As will be discussed below in greater detail, a portion of each bollard14is disposed within base12. The exposed portion13of each bollard14has a height H2extending from top surface16of base12to a freely exposed terminal end face28that is typically in a range between about 32 inches to about 42 inches with about 36 inches to about 40 inches being more common and about 39 inches being most common. Other heights can also be used. Each bollard14is also shown having a substantially square transverse cross section with all sides having a width W2in a range between about 10 inches to about 12 inches with about 11 inches being more common. Other widths and configurations can also be used.

Bollards14are spaced apart on center by distance D1that is typically in a range between about 3.5 feet to about 4.5 feet with about 3.75 feet to about 4.25 feet being more common and about 4 feet being most common. Other distances can also be used. Although fixed bollard system10is shown having five bollards14, in other embodiments other numbers of bollards14can be used. For example, fixed bollard system10can comprise at least three bollards14or six or more bollards14.

Each bollard14has a front face30an opposing back face32with opposing side faces34and36that extend therebetween. Bollards14are positioned back from front face20of base12by distance D2extending between front face20of base12and front face30of bollard14in a range between about 10 inches to about 16 inches with about 12 inches to about 14 inches being more common and about 13 inches being most common. Other distances can be used.

Discussion will now be made as to the structural components and methods of manufacturing bollards14and base12. The following discussion provides dimensions for one specific example for forming fixed bollard system10to sustain a K-12 impact test, as discussed above. It is again noted, however, that fixed bollard system10is not limited to bollard systems that can sustain a K-12 impact test and that in alternative embodiments, the dimensions for the different components can be varied.

As depicted inFIG. 3, each bollard14comprises a vertical support beam40. Each vertical support beam40typically comprises an I-beam and, more commonly, a wide flange beam (W-beam) having a nominal size of about 10 inches by 10 inches, a weight of about 100 pounds per foot and a length of about 56 inches. Other lengths and sizes can also be used. Of the length of 56 inches, 18 inches are typically embedded within base12while the remaining 38 inches extend above top surface16of base12. Vertical support beam40has a substantially I-shaped configuration that includes a front flange42, a back flange44, and a web46centrally extending therebetween. Each vertical support beam40extends between a top end48and an opposing bottom end50. Opposing channels52and54extend along the length of vertical support beam40on opposing sides of web46.

As depicted inFIG. 4, each bollard14further comprises a tube56disposed with channel52(FIG. 3) and a tube58disposed with channel54(FIG. 3) of vertical support beam40. In the present embodiment, each tube56and58has a substantially rectangular transverse cross section that is about 4 inches by 8 inches with a thickness of about 0.5 inches and a length of about 56 inches. As a result, each tube56and58is received within a corresponding channel52,54and extends along the full length thereof In the present embodiment, however, tubes56and58do not completely fill channels52,54. As such, as depicted inFIG. 7, an elongated filler plate64can be positioned within channel52(FIG. 3) between tube56and front flange42of vertical support beam40. An identical filler plate64can also be positioned within channel54(FIG. 3) between tube58and front flange42of vertical support beam40. Each filler plate64typically has a width of about 4 inches, a thickness of about 0.375 inches, and a length of about 56 inches.

As also depicted inFIG. 7, and as will be discussed below in greater detail, four pairs of bolt holes100A,100B,100C and100D are vertically spaced apart along bottom end50of vertical support beam40with bolt holes100A being the highest bolt holes and bolt holes100D being the lowest bolt holes. All of bolt holes100A-C have a diameter of about 1 inch while bolt holes100D have a diameter of about 1.5 inches. Each of the bolt holes of the pair of bolt holes100A,100B,100C and100D are laterally spaced apart and extend through front flange42of vertical support beam40, a corresponding filler plate64, a corresponding one of tubes56or58, and through back flange44of vertical support beam40. As a result, the aligned pairs of bolt holes100A-D form eight discrete channels through which bolts can pass for connecting tubes56,58and filler plates64to vertical support beam40. In addition, if desired, tubes56,58and filler plates64can be spot welded to vertical support beam40.

Turning toFIG. 5, a top plate60is positioned on an upper terminal end face of vertical support beam40. Top plate60typically has a substantially square configuration with side edge measuring 12 inches. Top plate60also typically has a thickness of about 1 inch and is welded to flanges42and44and to tubes56and58using a ¼ inch fillet weld. Other dimensions can be used for the top plate60.

As depicted inFIG. 6, a tubular cover62can be positioned over vertical support beam40so as to encircle and cover the exposed portion of vertical support beam40and tubes56and58. Each cover62typically has a length of approximately 38 inches, a thickness of about 1/16 inch or less, and an interior cross section that is substantially square with each side of a length of about 11.1 inches. Other dimensions can be used for the cover62. Cover62can be positioned over vertical support beam40and tubes56,58prior to mounting top plate60. Once top plate60is welded in place, as discussed above, cover62is then slid upward and butted against top plate60. Cover62is then secured in place by being welded to top plate60at its top and/or by being welded to vertical support beam40and/or tubes56,58at its base.

In an alternative method, cover62is typically made from a thin sheet metal that is bent into a four-side tube and then opposing ends, i.e., two edges of the sheet metal, are welded together to form the tube. In this embodiment, top plate60can initially be welded in place. Cover62, prior to welding the opposing ends together, can then be wrapped around vertical support beam40and then welded in place. Other methods for mounting can also be used.

Cover62is primarily ornamental in nature and functions to cover vertical support beam40and rectangular tubes56,58. As such, in alternative embodiments cover62can have a variety of alternative polygonal, circular, shaped or irregular configurations and can have alternative designs and features formed thereon.

Returning toFIG. 3, base12(FIG. 1) further comprises a laterally extending front beam70, laterally extending rear beam72, and a plurality of horizontal support beams74that are positioned therebetween and that are aligned with the corresponding vertical support beams40. Turning toFIG. 7, front beam70typically comprises an I-beam and, more commonly, a wide flange beam (W-beam) having a nominal size of about 8 inches by 5.25 inches, a weight of about 21 pounds per foot, and a length of about 24 feet. Alternative lengths and sizes can also be used. Again, front beam70has a substantially I-shaped configuration that includes a front flange110, a rear flange112, and a web114centrally extending therebetween. As will be discussed below in greater detail, rear flange112has a plurality of bolt holes100C extending therethrough to facilitate bolting front beam70to vertical support structure40.

Returning toFIG. 3, in one embodiment each horizontal support beam74comprises an I-beam and, more commonly, a wide flange beam (W-beam) with a nominal size of about 10 inches by 10 inches, a weight of about 68 pounds per foot, and a length of approximately 46 inches. Again, other lengths and sizes can be used. Horizontal support beam74has a substantially I-shape configuration that includes a top flange76, an opposing bottom flange78, and a web80centrally extending therebetween. Horizontal support beam74includes a first end84that connects to a vertical support beam40and an opposing second end86that connects to rear beam72.

As depicted inFIG. 4, first end84of horizontal support beam74is connected to vertical support beam40by an upper bracket88, a lower bracket90, and a pair of opposing side brackets92and94. As depicted inFIGS. 8 and 9, in one embodiment upper bracket88comprises an L-bracket that includes a base96and a flange98that orthogonally projects from an end thereof Upper bracket88has a length L3of about 8 inches, a height H3of about 4 inches, a width W3of about 14 inches and a thickness T3of about 1 inch. A pair of spaced apart bolt holes100A extend through flange98while four spaced apart bolt holes101extend through base96. All of the bolt holes100and101in upper bracket88have a diameter of about 1 inch.

As depicted inFIGS. 10 and 11, each lower bracket90comprises an L-bracket having a base102with a flange104orthogonally projecting from an end thereof Lower bracket90has a length L4of about 8 inches, a height H4of about 4 inches, a width W4of about 14 inches, and a thickness T4of about 1 inch. A pair of spaced apart, triangular shaped, stiffening wedges106extend between base102and flange104. Each stiffening wedge has two equal legs of about 4 inches long and a thickness of about 0.5 inch. Again, a pair of spaced apart bolt holes100D, each having a diameter of about 1.5 inches, extend through flange104while four spaced apart bolt holes101, each having a diameter of about 1 inch, extend through base102.

Turning toFIGS. 12 and 13, each side bracket92and94comprise an L-bracket having a base106and a flange108orthogonally projecting from an end thereof Each side bracket92,94has a length L5of about 8 inches, a height H5of about 4 inches, a width W5of about 8 inches, and a thickness T5of about 1 inch. Again, a pair of spaced apart bolt holes100A and100B extend through flange104while four spaced apart bolt holes101extend through base106. In the side brackets92and94, all of the bolt holes100A and B and101have a diameter of about 1 inch.

During assembly as depicted inFIG. 7, horizontal support beam74is coupled with vertical support beam40by butting first end84of horizontal support beam74against back flange44of vertical support beam40at second end50. Upper bracket88is mounted at the intersection of top flange76of horizontal support beam74and back flange44of vertical support beam40so that bolt holes100A of upper bracket88are align with bolt holes100A extending through vertical support beam40. Likewise, lower bracket90is positioned at the intersection of back flange44of vertical support beam40and bottom flange78of horizontal support beam74. Again, bolt holes100D on lower bracket90are aligned with bolt holes100D extending through vertical support beam40. Side brackets92and94are positioned at the intersection of back flange44of vertical support beam40and opposing sides of web80of horizontal support beam74. In this embodiment, each of bolt holes100B and C of side brackets92and94are aligned with corresponding bolt holes100B and100C extending through vertical support beam40. In addition, front beam70is positioned so that rear flange112butts against front flange42of vertical support beam40with bolt holes100C of front beam70being aligned with bolt holes100C extending through vertical support beam40. Here it is noted that front beam70is vertically spaced apart from a bottom terminal end face105of vertical support beam40by a distance X that is about 2.75 inches.

Turning toFIG. 5, in the above configuration bolts116, each having a diameter of about 1 inch, are then passed through all aligned bolt holes100A,100B and100C and fastened with threaded nuts so as to secure the aligned structures together. Bolts117, each having a diameter of about 1.5 inches, are also passed through all aligned bolt holes100D and fastened with threaded nuts so as to secure the aligned structures together. Also in this configuration, each bolt hole101in brackets88,90,92, and94is aligned with a corresponding bolt hole101extending through horizontal support beam74(FIG. 7). Bolts118, each having a diameter of about 1 inch, are passed through all align bolt holes101and fastened with threaded nuts. Accordingly, bolts116,117and118function to secure together front beam70, vertical support beam40, rectangular tubes56,58, filler plates64, brackets88,90,92, and94and horizontal support beam74. To further secure together the above mechanical engagement, a ¼ inch fillet weld can be formed along the intersecting surfaces between lower bracket90and horizontal support beam74and between lower bracket90and vertical support beam40. If desired, fillet welds can also be formed between the other mechanically connected surfaces.

Returning toFIG. 6, rear beam72comprises an I-beam and, more commonly, a wide flange beam (W-beam) with a nominal size of 6 inches by 4 inches with a weight of 12 pounds per foot and a length equal to that of front beam70. Rear beam72has a substantially I-shaped configuration which includes a front flange122, a rear flange124, and a web126centrally extending therebetween. As depicted inFIG. 4, brackets128and130are used to secure rear beam72to horizontal support beam74.

As depicted inFIGS. 14 and 15, each bracket128and130comprises a V-bracket that includes a first arm132and a second arm134orthogonally projecting from an end thereof Each bracket128and130has a length L6of about 5 inches, a height H6of about 5 inches, a width W6of about 4 inches, and a thickness T6of about 0.5 inch. A pair of laterally spaced apart bolt holes136extends through first arm132while a pair of vertically spaced apart bolt holes138extends through second arm134. Bolt holes136and138each have a diameter of about 0.5 inch.

As depicted inFIGS. 4 and 5, second arm134of brackets128and130are centrally mounted on opposing sides of web80of horizontal support beam74at second end74. Bolt holes138in brackets128and130are aligned with bolt holes extending through web80of horizontal support beam74so that bolts133can pass through bracket128, web80, and bracket130and be secured thereto by threaded engagement with nuts. In turn, front flange122of rear beam72is butted against the terminal end face at second end86of horizontal support beam74. Bolts142are then passed through bolt holes136in first arm132of brackets128and130and through aligned bolt holes in front flange122of rear beam72so as to secure together horizontal support beam74and rear beam72.

Next, as depicted inFIG. 16, rebar is positioned around front beam70, rear beam72, and horizontal support beam74. Specifically, a plurality of laterally spaced apart sections of looped rebar146are positioned in a loop that extends from front beam70to rear beam72above horizontal support beam74and from rear beam72to front beam70below horizontal support beam74. The portions of looped rebar146above and below horizontal support beam74are disposed in substantially parallel planes that form an upper surface150and an opposing lower surface152. A plurality of sections of lateral rebar148extend along the length of front beam70and rear beam72at spaced apart distances along upper surface150and lower surface152of looped rebar146. Loop rebar146typically comprises #5 rebar having a diameter of approximately ⅝ inch while the lateral rebar is typically #6 rebar having a diameter of 6/8 inch.

Once the rebar is positioned, a perimeter form can be built and concrete poured into the form so as to form a concrete slab that covers and encases the rebar, front beam70, rear beam72, and horizontal support beam74. The concrete is poured so that the resulting concrete slab, which defines the outer perimeter of base12, has the dimensions as previously discussed with regard toFIGS. 1 and 2.

The foregoing example provides specific measurements for each element of one embodiment of fixed bollard system10. In alternative embodiments, it is appreciated that each of the different discussed measurements can be varied by ±5%, ±10%, ±15%, or ±20%. This is especially true where fixed bollard system10need not sustain a K-12 impact test. Likewise, still other dimensions can also be used. Furthermore, it is appreciated that many of the members discussed herein are connected together by bolting so as to minimize the amount of welding required. Different sizes for the bolts can be used. The bolts can also be replaced with expansion bolts, rivets, and other conventional types of fasteners. Likewise, the bolts can be eliminated by securing the elements together using welding. In one typical embodiment, all structural parts described herein are made from structural steel (ST-50), all rebar are made from structural steel (ST-60), all bolts are grade-8, and the concrete has a minimum strength of 3,000 psi. Other materials can be used.

Different embodiments of the present have a number of unique advantages. For example, in one embodiment fixed bollard system10can have a low profile base12having a height that is less than 24 inches and more commonly less than 20 inches while still enabling the fixed bollard system10to sustain a K-12 impact test. This enables the system to be more easily retrofitted around existing structures within a town or city where it can be difficult to dig deep holes due to existing utility lines. Fixed bollard system10can also be made from standard off the shelf parts so that no complicated fabrication is required. For example, all I-beams used in the present system can be replaced by standard square or rectangular tubes and yet still be connected together using the above discussed bolted flanges or other fastening techniques.

Furthermore, because a majority of the fixed bollard system10can simply be bolted together, the inventive system provides relatively easy assembly and installation. Regarding installation, it is appreciated that the present system can be prefabricated in a shop to the extent as depicted inFIG. 6. That is, the complete system can be fabricated in a shop except for the addition of the rebar and concrete. The partial assembly can then be shipped to the desired location where it is positioned within a preformed hole or within an area bounded by a form. Once the rebar is added, the concrete can be poured and the fixed bollard system10is complete. Where an extended length of bollards are required, discrete sections of bollards can be formed end to end.