Expediently Installable Traffic Calming System

Abstract

A traffic calming system is provided that can remain in place on the ground without additional attachment while a vehicle grazes or traverses it. The traffic calming system includes a variety of modular units that can be laid out in any desired pattern as needed to direct a flow of traffic. The modular units can be connected together in an arrangement such as for a roundabout or splitter island. The modular units can be arranged individually as lane markers, such as for a bicycle lane or pedestrian lane, or to outline a roundabout or splitter island.

Claims

1. A lane marker for traffic calming comprising: a body configured for placement on a ground surface, the body comprising an upper surface, a lower surface, and a side surface between the upper surface and the lower surface; and wherein: the upper surface extends at an angle upwardly from an upper edge of the side surface to a higher location, the lower surface is frictionally enhanced with respect to the ground surface, and a height of the side surface, the angle of the upper surface, and a coefficient of friction of the lower surface with respect to the ground surface are selected so that a lateral component of a load applied on the body is less than a friction force generated between the lower surface and the ground surface.

2. The lane marker of claim 1, wherein the angle of the upper surface ranges from 5° ±5% to 30° ±5%.

3. The lane marker of claim 1, wherein the ground surface is an asphalt material or a concrete material, and the coefficient of friction of the lower surface is at least 0.25 ±5% with respect to the ground surface.

4. The lane marker of claim 1, wherein the height of the side surface ranges from 0.0625 inch to 2.0 inch ±5%.

5. The lane marker of claim 1, wherein the side surface extends circumferentially around the body, and the upper surface of the body has a conical or truncated conical configuration.

6. The lane marker of claim 1, wherein the body has a diameter ranging from 1.0 feet ±5% to 4.0 feet ±5%.

7. The lane marker of claim 1, wherein the body has a rectangular configuration, and the side surface extends along a length of the rectangular configuration.

8. The lane marker of claim 1, wherein the lower surface is textured to provide the coefficient of friction.

9. The lane marker of claim 1, wherein the lower surface is formed of elastomeric material having a Shore D hardness of 75 or less.

10. The lane marker of claim 9, wherein the elastomeric material is a urethane material or a rubber material.

11. The lane marker of claim 1, wherein the upper surface and the lower surface are integrally formed from an elastomeric material.

12. The lane marker of claim 1, wherein an aperture is formed in the body at the higher location.

13. The lane marker of claim 1, wherein a recess is formed in a central region of the lower surface, and a weight is affixed within the recess.

14. A traffic calming feature for vehicular traffic comprising: a plurality of the lane markers of claim 1, the lane markers arranged in a pattern on a roadway surface of asphalt or concrete, and wherein the pattern comprises a roundabout, a splitter island, a bicycle lane, or a pedestrian lane.

15. A traffic calming system, comprising: a skeletal structure comprising: a plurality of boards arranged in a skeletal pattern on a ground surface of a vehicle roadway, each of the boards comprising an upper surface and a lower surface, and having an elongated configuration with a length extending between end regions, the length greater than a width, and a thickness between the upper surface and the lower surface, the thickness less than the width, a first portion of the boards comprising perimeter boards and a second portion of the boards comprising interior boards, and a plurality of connectors attaching the end regions of adjacent ones of the boards together in the skeletal pattern on the ground surface; and wherein: the perimeter boards are connected together at perimeter joints at adjacent end regions to form a perimeter of the skeletal pattern, and the interior boards are connected to adjacent end regions of the perimeter boards at the perimeter joints and extend across an interior of the skeletal pattern to provide cross bracing in a plane across the skeletal structure.

16. The traffic calming system of claim 15, wherein a further portion of the end regions of the interior boards are connected together at a central joint within the interior of the skeletal structure.

17. The traffic calming system of claim 15, wherein a portion of the interior is free of the interior boards.

18. The traffic calming system of claim 15, wherein each of the perimeter boards has a side surface having a dimension extending between the lower surface and the upper surface of at least 0.0625 inch ±5%, and the upper surface of each of the perimeter boards extends at an angle upwardly from an upper edge of the side surface to a higher location, the angle ranging from 5° ±5% to 30° ±5%.

19. The traffic calming system of claim 15, wherein the lower surface has a coefficient of friction of at least 0.25 ±5% with respect to the ground surface of asphalt or concrete.

20. The traffic calming system of claim 15, further comprising a friction enhancing element affixed to or integral with the lower surface of at least a portion of the perimeter boards and/or the interior boards.

21. The traffic calming system of claim 20, wherein the friction enhancing element comprises a material having a coefficient of friction of at least 0.25 with respect to the ground surface of asphalt or concrete, a material having a surface texture, an elastomeric material having a Shore A hardness of 60 or less, or a painted layer with hard ceramic or diamond particles, or a combination thereof.

22. The traffic calming system of claim 15, wherein each connector comprises a first portion connectable to a surface of a first board and a second portion connectable to a surface of a second board.

23. The traffic calming system of claim 15, wherein the connectors are recessed into correspondingly shaped recesses formed in the surfaces of the boards.

24. The traffic calming system of claim 15, wherein the connectors have a shape chosen from a rectangular shape, a bar shape, a square shape, a dovetail shape, a dog-bone shape, a T-shape, and an I-shape.

25. The traffic calming system of claim 15, wherein each of the perimeter boards has a trapezoidal plan shape having parallel sides extending along the length of the board and non-parallel sides extending at non-orthogonal angles across the width of the board.

26. The traffic calming system of claim 15, wherein the boards are formed of an elastomeric material.

27. The traffic calming system of claim 15, wherein the skeletal pattern comprises a roundabout central island pattern or a splitter island pattern.

28. A method of making a traffic calming system, comprising: providing the traffic calming system of claim 15; and installing the boards in the skeletal pattern on the ground surface at an intersection of vehicle roadways.

Description

DESCRIPTION OF THE DRAWINGS

[0067] Reference is made to the following detailed description taken in conjunction with the accompanying drawings in which:

[0068] FIG. 1 is a side view of an embodiment of lane marker for a traffic calming system.

[0069] FIG. 2 is a top view of the lane marker of FIG. 1.

[0070] FIG. 3 is a bottom view of the lane marker of FIG. 1.

[0071] FIG. 4 is a schematic illustration of a load on a lane marker.

[0072] FIG. 5 is a further schematic illustration of the load components of the load on the lane marker of FIG. 4.

[0073] FIGS. 6A-6D illustrate further textured lower surfaces.

[0074] FIG. 7 is a schematic illustration of a layout of lane markers in a traffic intersection.

[0075] FIGS. 8A-8D are schematic illustrations of layouts of lane markers to demarcate a bicycle lane.

[0076] FIGS. 9A-9B illustrate an embodiment of a lane marker with a vertical post.

[0077] FIG. 10 is a perspective view of an embodiment of modular units for a roundabout.

[0078] FIG. 11 is a perspective view of the modular units of FIG. 10 prior to installation on a ground surface.

[0079] FIG. 12 is an isometric view of an embodiment of modular units for a roundabout.

[0080] FIG. 13 is a top plan view of the embodiment of FIG. 12.

[0081] FIG. 14 is an isometric view of a perimeter joint between the modular units of FIG. 12.

[0082] FIG. 15 is an isometric view of the perimeter joint of FIG. 13 with a connector plate illustrated in phantom.

[0083] FIG. 16 is a plan view of a further perimeter joint illustrating mid plane connector bars with reference to the connector plate of FIG. 15.

[0084] FIG. 17 is an isometric view of a central joint between the modular units of FIG. 12.

[0085] FIG. 18 is an isometric view of the central joint of FIG. 17 with a connector plate illustrated in phantom.

[0086] FIG. 19 is a bottom view of an embodiment of a modular unit.

DETAILED DESCRIPTION

[0087] In some embodiments, a traffic calming system can include one or more lane markers that can be located individually or in a group on a ground surface. The lane marker can surprisingly remain in place on a roadway surface of asphalt or concrete as a vehicle grazes or traverses the lane marker without the need for additional attachment, such as anchors or adhesive. The lane marker can have a variety of configurations in plan view, such as circular, sometimes referred to as a dot, or rectangular, such as a board.

[0088] Referring to FIGS. 1-5, which illustrates an embodiment of a lane marker 10 in the form of a dot, the lane marker includes a body 15 configured for placement on a ground surface of, for example, asphalt or concrete. The body comprises an upper surface 20, a lower surface 30, and a side surface 40 extending between the lower surface and the upper surface. The upper surface 20 extends at an angle 22 upwardly from an upper or leading edge 42 at the top of the side surface to a higher location. The lower surface 30 is frictionally enhanced with respect to the ground surface. The height of the side surface 40, the angle 22 of the upper surface 20, and the coefficient of friction (CoF) of the lower surface 30 with respect to the ground surface can be selected to prevent movement of the lane marker when impacted by a vehicle tire.

[0089] Referring to FIGS. 4 and 5, friction is the resistance to sliding between two surfaces, which is determined by the static coefficient of friction (CoF) between the two materials at the surfaces. The amount of resistance to movement of an object resting on a surface is a function of the CoF and the applied load, F.sub.N, normal to the two surfaces. The amount of resistance, the friction force, F.sub.f, that can be generated between two surfaces can be calculated by multiplying the force or load normal to the surfaces, F.sub.N, by the CoF: F.sub.N*CoF=F.sub.f.

[0090] When the load is applied at another angle to the surface, the load (indicated schematically at A in FIG. 5) is divided into load vectors, one parallel to the surface (indicated schematically at B) and one normal to the surface (indicated schematically at C). The load normal to the surfaces determines the friction force (indicated schematically at D). The load parallel to the surfaces determines whether the object moves laterally or not. If the friction force exceeds the parallel load component, then the object remains stationary; if the parallel load component exceeds the friction force, the object moves. In the case of a lane marker, no movement is desired when impacted by a vehicle tire. This can be achieved by increasing the static CoF of the lower surface or by changing the angle of the upper surface at the leading edge or a combination thereof. The shallower the angle, the more the load from the vehicle is transferred as a downward, normal component to generate the friction force. The higher the CoF, the higher the percentage of that normal component is amplified into the friction force. For instance, if the CoF is 2, the normal component of the vehicle impact load is doubled. This in turn allows the lane marker to employ a steeper angle, which can be desirable, for example, to increase visibility of the lane marker or be more noticeable if a driver impacts the lane marker.

[0091] Another component specific to the lane marker is the height of the leading edge, or the height of the upper edge of the side surface (the dimension between the lower surface and the upper surface), along the portion of the marker likely to be impacted by a vehicle tire. Vehicles have different diameter tires, and the load components on the marker can vary depending on how each tire diameter interacts with the geometry of the lane marker. The leading edge can be located at a height at which a tire of a particular diameter does not contact the leading edge, but rather contacts the sloped upper surface, which yields the same load components (normal, parallel) regardless of tire diameter. However, if the leading edge is sufficiently high, it can receive tire contact first, before the tire contacts the sloped surface. In this case, the tire diameter can yield different load components, with larger tire diameters being better for achieving the goal of no movement (or less lateral load). Since the friction load and lateral load are both a function of the applied load of the vehicle, the vehicle's weight is not determinative, and only the ratio of the two loads determines if the lane marker moves.

[0092] Thus, the height of the leading edge and the angle of the upper surface at the leading edge can be selected to decrease the lateral force component and increase the downward force component, thereby increasing the frictional force component relative to the lateral force component. Additionally, the static coefficient of friction of the lower surface of the lane marker can be selected to increase the magnitude of the frictional force. In this manner, the lateral force component of the tire can be offset by the frictional force on the lower surface, and the marker can remain in place.

[0093] An analysis was performed based on a lane marker configuration as illustrated in FIGS. 4-5, in which the height of the leading edge was 0.19 inch and the angle of the upper surface was 13.19°. The analysis varied the static coefficient of friction (CoF) and the tire diameter as indicated in Table 1. The tire lateral force component (positive) and frictional force component (negative, opposite the movement of the vehicle) were determined and added together. The results are given as a percentage of the vehicle load at a given tire diameter. A negative percentage indicates that the lane marker does not move when run over by a tire, that is, the friction force exceeds the lateral load generated by the vehicle.

TABLE-US-00001 TABLE 1 Resultant Lateral Load as a Percent of Vehicle Load at a Given Tire Diameter CoF 14″ 16″ 20″ 36″ 0.25  −2%  −2%  −2%  −2% 0.5 −26% −26% −26% −26% 0.75 −50% −50% −50% −50% 1 −75% −75% −75% −75% 1.25 −99% −99% −99% −99% 1.5 −123%  −123%  −123%  −123%  1.75 −148%  −148%  −148%  −148%  2 −172%  −172%  −172%  −172% 

[0094] For example, for a static coefficient of friction of 0.25, the sum of the lateral force components (the tire lateral force component and the frictional force component) is equal to −2%. Since this number is negative, the lane marker does not move.

[0095] In this analysis, a CoF of 0.25 results in a negative resultant lateral load because the angle is so shallow, and the majority of the vehicle's weight is applied normally to the friction surface as opposed to laterally (about a 4-1 ratio). However, other factors can also affect the coefficient of friction of the lower surface of the lane marker in the field. For example, the ground surface can be wet or can be coated with debris such as loose dirt or sand particles. The lane marker can degrade over time. Thus, the coefficient of friction of the friction enhancement of the lane marker can be selected to account for such variables. For example, in some embodiments, a CoF can be provided to generate at least a −50% resultant load to provide a margin for a change in the CoF over time.

[0096] In some embodiments, the angle of the upper surface can range from 5° to 30° with a tolerance of ±5%. In some embodiments, the angle of the upper surface can range from 5° to 25° with a tolerance of ±5%. The angle is constant from the leading edge to at least a distance of 2 inches from the center or from a highest location of the marker. The maximum height of the lane marker is 2 inches ±5% and is preferably no greater than 3 inches ±5% to remain below the lowest vehicle clearance allowable under the Federal Highway Administration regulations. However, greater heights may be used, depending on the application. In some embodiments, the angle of the upper surface is less than 30° with a tolerance of ±5%. It will be appreciated that the larger the angle, the greater the lateral load component, tending to result in movement of the lane marker when impacted by a vehicle.

[0097] In some embodiments, the height of the leading edge of the lane marker, or the dimension of the side surface between the lower surface and the upper surface, is less than 2 inches with a tolerance of ±5%. In some embodiments, the height of the leading edge can range from 0.0625 inch to 2.0 inches with a tolerance of ±5%. The side surface is preferably vertical or orthogonal with respect to the ground surface with a tolerance of 5%. In some embodiments, the height of the leading edge can be less than 0.625 inch; however, this can result in an edge that is too sharp and subject to excessive wear from impacts.

[0098] In some embodiments, the lower surface has a static coefficient of friction of at least 0.25 ±5% with respect to a ground surface of asphalt or concrete. In some embodiments, the lower surface has a static coefficient of friction of least 0.75 with respect to a ground surface of asphalt or concrete. In some embodiments, the static coefficient of friction is at least 0.25, at least 0.5, at least 0.75, at least 1.0, at least 1.25, at least 1.5, at least 1.75, or at least 2.0, with a tolerance of ±5%. The static coefficient is typically greater than a dynamic coefficient of friction. To minimize sliding of the lane marker should it start moving, in some embodiments, the dynamic coefficient of friction is within 20% of the static coefficient of friction. In some embodiments, the dynamic coefficient of friction within 5% of the static coefficient of friction.

[0099] The coefficient of friction can be determined by several factors, including the surface topography or texture, how the surface behaves under deformation, the hardness of the surface material, and similar characteristics of the mating surface (e.g., the road surface).

[0100] In some embodiments, a friction enhanced lower surface can include a texture on the lower surface of the lane marker. For example, the lower surface 30 can be formed with multiple upraised portions 32 arranged in any suitable pattern. In some embodiments, upraised portions have a dimension of at least 0.005 inch ±5%.

[0101] One example of a suitable pattern is shown in FIG. 3. In some embodiments, the texture can be molded into the surface during fabrication. FIGS. 6A-6D illustrate a variety of patterns that can be molded into the surface. In some embodiments, the lane marker can be formed as a single unitary body, for example, by molding, and a mold can include a suitable texture on the surface corresponding to the lower surface of the lane marker. In some embodiments, the lane marker can be formed with an upper body 15a and a friction enhancement element 15b having a textured surface can be attached to a bottom of the upper body. (See FIG. 1.) In some embodiments, the friction enhancement element can cover all or substantially all of a bottom of the body. In some embodiments, a metal or polymer plate having a textured surface can be attached to the lower surface in one or more locations. The plate can be attached in any suitable manner, such as with an adhesive or mechanical or magnetic fasteners. In some embodiments, several friction enhancement elements can be attached at spaced locations to the bottom of body. In some embodiments, the lower surface can be provided as a different material from the upper body of the lane marker. In some embodiments, the lower surface can be a painted layer with hard ceramic and/or diamond particles.

[0102] In some embodiments, a friction enhanced lower surface can be fabricated with an elastomeric material having a Shore A hardness of 90 or less, 80 or less, 60 or less, or 40 or less. In some embodiments, a friction enhanced lower surface can be fabricated with an elastomeric material having a Shore D hardness of 75 or less. In some embodiments, the material can be a urethane material or a rubber material.

[0103] In some embodiments, the body, the upper body, and/or the lower body of the lane marker can be fabricated from a thermoset or thermoplastic elastomer, urethane, thermoplastic olefin, ethylene propylene diene monomer (EPDM), nitrile, amide, or polyester-based elastomer. In some embodiments, the body, the upper body, and/or the lower body of the lane marker can be fabricated from a polymer material or a metal or metal alloy material, or combinations thereof. In some embodiments, the upper body of the lane marker can be fabricated from a polymer material such as polyvinyl chloride (PVC) or acrylonitrile butadiene styrene (ABS). In some embodiments, the friction enhanced lower surface can be fabricated with a material having a hardness less than the hardness of the upper body of the lane marker. In some embodiments, the body or the upper body of the lane marker is fabricated from a material that can be driven over without cracking or breaking.

[0104] A lane marker can have a variety of configurations in plan view, such as circular, sometimes referred to as a dot, or rectangular, such as a board. In some embodiments, a circular lane marker or dot can have a conical shape with a circular configuration in plan view rising to a maximum height at the center (as in FIG. 1). The angle of the conical shape can be selected as above. In some embodiments, the diameter can range from 4 inches to 30 inches, although greater or lesser diameters can be used depending on the application. In some embodiments, the maximum height can range from 1 inch to 3 inches, although greater or lesser maximum heights can be used depending on the application. In some embodiments, the edge height can range from 0.0265 inch to 2.0 inches with a tolerance of ±5%, although greater or lesser edge heights can be used depending on the application.

[0105] The lane markers can be laid out by a suitable lay-out machine that can place them at suitable intervals. Lane markers with a circular plan configuration can be laid out in any orientation. The lane markers can also be picked up by machine. The lane markers can also be laid out and/or picked up manually.

[0106] The lane markers can be laid out in any desired pattern to direct the flow of traffic. For example, lane markers can be used to demarcate a roundabout, a splitter island, a bicycle lane, a pedestrian lane, a traffic diverter, or a lane divider. FIG. 7 illustrates an example of a layout of lane markers 10 at an intersection of four roads. FIGS. 8A-8D illustrate examples of lane markers 10 used to demarcate a bicycle lane from a vehicle traffic lane. Different shapes of lane markers can be combined, as also indicated in FIGS. 8B and 8D.

[0107] The lane markers can be used in permanent installations or in temporary installations. In some embodiments, the lane marker can also be affixed to the ground surface with another mechanism, such as ground anchors, adhesive, or magnetic fasteners. The lane marker can include an opening therein for a ground anchor.

[0108] In some embodiments, the lane marker can include an opening in the upper surface to hold a vertical marker, delineation post, reflector, light, or sign. FIGS. 9A and 9B illustrate an embodiment of a lane marker 10, similar to the embodiment of FIGS. 1 and 1, with a vertical post 50 within a central opening. The lane marker can include a reflective material, for example on all or a portion of the upper surface and/or along the edge. In some embodiments, the lane marker can be fabricated with a color, such as yellow, for better visibility. The lane marker can be fabricated with a desired sheen on the upper surface, such as flat, eggshell, semi-gloss, or gloss.

[0109] In some embodiments, the lane marker can be solid. In some embodiments, the lane marker can be hollow. In some embodiments, the lane marker can include a hollow interior that can be filled with another material, such as water, sand, or recycled materials. Recycled materials can include recycled car tires.

[0110] In some embodiments, the lane marker can house electronic components or sensors. In some embodiments, the lane marker can house a solar or piezoelectric energy generator. In some embodiments, the lane marker can house smart devices to enable communication with other smart devices, such as in a bus, car, truck, bicycle, or a communication hub. In some embodiments, the lane marker can communicate with other lane markers to control attached features such as lights, signs, and reflectors.

[0111] FIGS. 10-19 illustrate an embodiment of a traffic calming system comprising a roundabout system 110 employing a plurality of modular units 120 in the form of elongated boards 122 arranged in a skeletal structure 115 on a ground surface 117 of a vehicle roadway. The skeletal structure includes a plurality of perimeter boards 130 arranged in a skeletal pattern to form an outline of a roundabout and a plurality of interior boards 140 arranged radially from a central region to the perimeter boards. Each of the boards is generally elongated and has an upper surface and a lower surface. The boards are configured such that a length is relatively greater than a width and the width is relatively greater than a thickness between the upper and lower surfaces. The boards are connected to adjacent boards at end regions via connectors 150 to form joints, thereby forming a stable skeletal structure. The perimeter boards 130 are connected together at perimeter joints at adjacent end regions 132 to form a perimeter of the skeletal pattern. The interior boards 140 are connected at end regions 142 to adjacent end regions 132 of the perimeter boards at the perimeter joints and extend across an interior of the skeletal pattern to provide cross bracing in a plane across the skeletal structure. Areas between the connected boards within the perimeter can be left free of boards, as illustrated in FIG. 10.

[0112] The roundabout can surprisingly be driven over after installation without shifting on the ground surface and without the need for additional attachments to the ground surface, such as ground anchors or an adhesive. The roundabout can surprisingly be driven over after installation without the need for any additional boards in the interior of the roundabout. The roundabout system can handle lateral loading on the perimeter from vehicles that graze or traverse the roundabout.

[0113] The boards can be arranged in any desired skeletal pattern. For example, the perimeter boards, which can be trapezoidal in plan view, can be arranged in any polygonal pattern, such as hexagonal, octagonal, or dodecagonal. The trapezoidal boards can be arranged as straight-line segments of arcs of a circle, to form a generally circular roundabout of any diameter. The interior boards can be arranged to also connect to the joints between adjacent perimeter boards to provide cross bracing, thereby stabilizing the skeletal structure. Typically, at least three boards are connected at a joint to stabilize the boards in the skeletal pattern. Portions between the boards within the area of the skeletal pattern can be left free of other boards.

[0114] Connectors 150 are provided to attach ends of adjacent boards together at the joints to form the desired pattern. More particularly, end regions of each board are shaped to abut end regions of one or more adjacent boards. A connector is attached to each of the end regions of the adjacent abutting boards, thereby connecting the boards at a joint.

[0115] In some embodiments, a connector 150 can be a plate that overlies each of the end regions of adjacent boards. See FIG. 14. Fasteners, such as screws or bolts, can attach the plate to each board. In the embodiment illustrated, the connector plate is configured such that a portion of the plate is connectable to an upper surface of each of the boards. FIG. 15 illustrates the connector plate 150 in phantom at a perimeter joint to indicate how the end regions of the adjacent boards are shaped and how the connector plate overlies the end regions of the three adjacent boards. At least two mechanical fasteners (e.g., screws) are used to fasten the plate to each board. However, a single fastener or more than two fasteners per board can be used.

[0116] FIGS. 17 and 18 illustrate a connector plate 150 that connects the radial interior boards at a central joint. The connector is a plate that overlies end regions of each of the radial boards. FIG. 18 in particular illustrates the plate in phantom to indicate how each of the radial boards is shaped to join together at the central joint. In this embodiment, twelve radial boards are shown. Two radial boards 140a meet in linear alignment. Two further radial boards 140b orthogonally abut the two linearly aligned radial boards. Four radial boards 140c have end regions shaped to fit into the right angle formed by the four orthogonally abutting boards. Four further radial boards 140d have end regions shaped to fit between each of the four radial boards and the orthogonal boards. The connector plate 150 is sized to overlie all of the end regions of the twelve boards. At least two mechanical fasteners (e.g., screws) are used to fasten the plate to each board. In some instances, more than two fasteners, e.g., four fasteners, can be used to fasten the plate to each board. However, a single fastener or another number of fasteners can be used.

[0117] It will be appreciated that other configurations of the end regions of the boards can be used. Similarly, a different number of radial boards can be used, for example, for smaller or larger roundabouts.

[0118] In some embodiments, a recess, which can have a complementary shape with each portion of the connector, can be machined or molded into the upper surfaces of the boards to form a seat for each portion of the connector so that the connector is flush or below the surrounding upper surface. In some embodiments, the connector can be mounted on the surface with no recess.

[0119] Any suitable fasteners can be used to attach the connectors to the boards. In some embodiments, fasteners can include bolts or screws and washers. In some embodiments, apertures for the fasteners can be predrilled in the boards, and in some embodiments, no pre-drilling is required to install the fasteners. In some embodiments, apertures can include wider portions for sub-flush washers. In some embodiments, the fasteners can be taken out and replaced multiple times with no or minimal loss in thread strength. For example, the connectors can be readily removed to replace a damaged board or section of boards or to remove the roundabout.

[0120] Fastening the connectors from above to the upper surface of the boards, as illustrated in FIGS. 14 and 17, can simplify installation and repair or removability. However, in some embodiments, the connector can be fastened to a lower surface of the boards. For example, in some embodiments, a connector plate can include multiple upwardly facing threaded attachments, such as externally threaded screws or bolts or internally threaded sockets. The boards can include apertures located to align with the attachments. For assembly, the connector plates can be placed in position on the ground surface and the boards can be placed over the connector plates with the apertures aligned with the upwardly facing attachments. The attachments can then be fully connected.

[0121] In some embodiments, the connector can be provided as a bar at a midplane of the board thickness between the upper and lower surfaces. Fasteners, such as bolts or screws, can go through aligned apertures in the board and the bar. Midplane bars are illustrated schematically in FIG. 16. In some embodiments, one end of each bar can be embedded into one end of a board during a manufacturing process, for example, by a molding process. A recess can be machined or molded into the other end. During assembly in the field, the protruding end of the connector bar can be inserted into the recess of an adjacent board and fastened into position.

[0122] The connector can have any suitable configuration. In the embodiments shown, the connector is configured as a rectangular plate or bar. In some embodiments, the connector can have other configurations, such as, without limitation, a square shape, a dovetail shape, a T-shape, an I-shape, or a dog-bone shape.

[0123] The traffic calming system can be placed on top of any suitable supporting ground surface, such as a road surface of asphalt or concrete. The traffic calming system can be installed over existing pavement with no modification to the existing pavement. The traffic calming system can be installed relatively rapidly, more quickly than traditional roundabouts, resulting in minimal traffic disruption.

[0124] In some embodiments, additional friction enhancements can be applied to or formed in or on the lower surface of the modular units, as described above with respect to the lane marker. Friction enhancements can include a textured surface on the lower surface of the modular unit. In some embodiments, a textured surface can be molded into the unit during fabrication. In some embodiments, a textured surface can be applied to the lower surface of the unit, as illustrated in FIG. 19. For example, a metal or hard polymer plate having a textured surface can be attached to the lower surface in one or more locations. The plate can be attached in any suitable manner, such as with an adhesive or mechanical or magnetic fasteners.

[0125] The components of the traffic calming system can be fabricated off site in advance and shipped to the installation site as a kit. The components (e.g., boards, connector plates, and fasteners) can be palletized and, in some embodiments, can be movable using a single forklift vehicle. See FIG. 11. The modular units can then be laid out in the desired pattern at the desired location. The connectors can be attached to the modular units at each joint. In some embodiments, the traffic calming system can be installed at the site in less than an hour.

[0126] Optionally, the modular units can also be anchored to the ground via ground anchors if desired. One or more apertures can be provided in the units for this purpose. For example, FIG. 14 illustrates two apertures 136 in each of the perimeter boards 130 that can be used to insert ground anchors for a roundabout system. Additional anchoring to the ground can be desirable if, for example, a traffic calming system is intended to be permanently installed in a location.

[0127] In some embodiments, the modular units can be formed into other configurations and skeletal patterns, in addition to a generally circular roundabout. For example, boards can be formed into a splitter island, which can have a variety of configurations, such as triangular, trapezoidal, rectangular, and square and combinations thereof. The configuration can depend on the traffic conditions and roadway type, size, and application. For example, a splitter island configuration can include a long rectangular section with a widened rounded section at one end. Perimeter boards can be arranged and connected to define the perimeter, and interior boards can be arranged and connected as cross members within the perimeter to stabilize the skeletal structure.

[0128] The modular units, e.g., boards and or lane markers, can be made of any suitable material. In some embodiments, a polymer material can be used. The material can be elastomeric, thermoplastic, or a combination of thereof to achieve desired characteristics. A material that can be driven over without damage can be used.

[0129] Suitable material compositions can include one or more of a polyolefin, poly(methyl methacrylate), acrylonitrile butadiene styrene, polyethylene terephthalate (PET), polybutylene terephthalate, polycarbonate, polyamide, and polyoxymethylene. In some embodiments, polyolefins such as polypropylene (PP), polyethylene (PE), or high density polyethylene (HDPE) can be used as a base polymer. In some embodiments, engineering polymers such as polyethylene terephthalate (PET) or polyamide (Nylon) can be used as a base polymer. In some embodiments, the modular units can be made from recycled and/or recyclable materials. In some embodiments, crumb rubber (CR), obtained from recycled tires, can be used as an additive to a base polymer. In some embodiments, a thermoplastic urethane or polyurethane (TPU) can be added to improve toughness, particularly to PET. In some embodiments, the units can be made of primarily high density polyethylene (HDPE) with the addition of fiber reinforcement, such as fiberglass, added for stiffness and strength. In some embodiments, the units can be made of HDPE with no additional fiber reinforcement.

[0130] Modular units can be manufactured in any suitable manner, such as by molding, an extrusion process, or a pultrusion process. In some embodiments, the units can be produced by a molding process, such as compression molding, which uses high pressure to force a thermoplastic material into a tool. The process can be selected as appropriate for the application, accounting for factors such as large complex parts and extremely high viscosity resins. A mold for each size and shape of unit can be provided. In some embodiments, board stock from suitable materials is also commercially available in a variety of sizes and lengths and can be purchased. Multiple boards can be cut to appropriate sizes from a single longer board.

[0131] Connectors for connecting the modular units together can be made from any suitable material. In some embodiments, the connector can be made from a metal or metal alloy. In some embodiments, the connector can be made from a urethane rubber. In some embodiments, the connector can have a hardness ranging from about Shore Hardness 30 A to about Shore Hardness 50 D. In some embodiments, the connector can have a Shore 90 A hardness. In some embodiments, a connector plate can have a thickness that can range from 1/16 inch ±5% to 2.5 inches ±5%. In some embodiments, the connector can be 0.5″ thick ±5%.

[0132] A traffic calming system as described herein can be placed on top of any suitable supporting surface. In some embodiments, the roundabout can be placed directly over an existing road surface, for example, of asphalt or concrete. The traffic calming system be installed over existing pavement with no modification to the existing pavement.

[0133] The traffic calming system can be used for a variety of applications such as roundabouts, splitter islands, perimeter islands, bicycle lanes, pedestrian refuge areas, elevated platforms, and speed mitigation.

[0134] A traffic calming system as described herein can be installed relatively rapidly, often more quickly than traditional traffic calming, resulting in minimal traffic disruption. The traffic calming system can be driven over after installation. In some embodiments, installation time can be reduced by 75%, 85%, 90% or 95% using this system and method. In some embodiments, the cost of fabricating and installing a traffic calming system can be reduced by 25%, 50%, 75%, 85%, 90% or 95%.

[0135] A traffic calming system as described herein can have minimal maintenance costs. If a modular unit is damaged, it can be replaced easily and quickly. The traffic calming system does not need to be painted. Modular units can be manufactured in a variety of colors and any desired color scheme can be selected.

[0136] As used herein, “consisting essentially of” allows the inclusion of materials or steps that do not materially affect the basic and novel characteristics of the claim. Any recitation herein of the term “comprising,” particularly in a description of components of a composition or in a description of elements of a device, can be exchanged with “consisting essentially of” or “consisting of.”

[0137] It will be appreciated that the various features of the embodiments and aspects described herein can be combined in a variety of ways. For example, a feature described in conjunction with one embodiment or aspect may be included in another embodiment or aspect even if not explicitly described in conjunction with that embodiment or aspect.

[0138] To the extent that the appended claims have been drafted without multiple dependencies, this has been done only to accommodate formal requirements in jurisdictions that do not allow such multiple dependencies. It should be noted that all possible combinations of features that would be implied by rendering the claims multiply dependent are explicitly envisaged and should be considered part of the invention.

[0139] The present technology has been described in conjunction with certain preferred embodiments and aspects. It is to be understood that the technology is not limited to the exact details of construction, operation, exact materials or embodiments or aspects shown and described, and that various modifications, substitution of equivalents, alterations to the compositions, and other changes to the embodiments and aspects disclosed herein will be apparent to one of skill in the art.