EP1957714A1

EP1957714A1 - Traffic control intersection

Info

Publication number: EP1957714A1
Application number: EP06827977A
Authority: EP
Inventors: Jozef Goj
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-11-24
Filing date: 2006-11-22
Publication date: 2008-08-20
Also published as: CN101316965A; EP1957714A4; JP2009517564A; NZ569366A; AU2006317502A1; MX2008006718A; AU2006317502B2; WO2007059563A1; CA2630869A1; US20090052983A1

Abstract

There is disclosed a traffic control intersection (10) having a first road (12) and a second road (14) running crosswise relative to the first road. Pathways (28), (36), (48) and (56) are provided to enable vehicles travelling along either of the roads to turn into the corresponding lane (leftmost or rightmost lane) in the other road. Two of the pathways (36) and (56) extend over lanes (20) of the second road but are at a different elevation to those lanes so that vehicles on these pathways are not obstructed by vehicles travelling along the lanes (20). The invention also extends to other, more complex intersection configurations employing a similar principal. Also disclosed is a traffic roundabout that defines a utility space for various uses, a pedestrian walkway, and a method of managing a road accident site.

Description

I

TRAFFIC CONTROL INTERSECTION

TECHNICAL FIELD

This invention relates to traffic control. More particularly, the invention relates to a traffic control intersection for leading traffic from lanes in one road into respective corresponding lanes in another road via a pathway which avoids the need for the traffic to stop.

BACKGROUND ART

One of the factors affecting the smooth and continuous flow of vehicular traffic along major roads such as freeways is the existence of intersections, even though these serve the vital purpose of enabling traffic to enter and exit these freeways.

One may consider a typical scenario in which the driver of a vehicle travelling along a freeway wishes to turn right into a second road which extends crosswise relative to the freeway. In such a scenario, the conventional manner of allowing a vehicle to make such a right turn is to provide an exit pathway extending leftwards from the leftmost lane of the freeway. This exit pathway, typically in the form of an exit ramp, joins the second road at a T-junction. The driver can thus use the exit pathway to travel from the freeway to the second road, and can then turn right into the second road. Typically the second road will extend underneath or over the freeway in order to cross it.

A disadvantage of this conventional intersection configuration is that it requires all vehicle drivers wishing to turn left or right from the freeway into the second road to be in the leftmost lane of the freeway so as to have access to the exit pathway. This in turn requires that those vehicles that were travelling in lanes other than the leftmost lane must merge into the leftmost lane, and also requires that existing traffic in the leftmost lane is often required to slow down to give way to such vehicles entering that lane. The amount of traffic in the leftmost lane thus increases - and can even as much as double - leading to a risk of traffic congestion

In addition, the vehicles making use of the exit pathway are then required to come to a complete halt at the T-junction between the exit pathway and the second road. If there is much traffic making use of the exit pathway, this can cause a backup of vehicles along the exit pathway to the freeway, and even possibly vehicle congestion on the freeway itself.

The need for vehicles to merge from other lanes into the leftmost lane is even more disadvantageous given that road rules typically require that lanes to the right of the leftmost lane, particularly the rightmost lane, are for channelling traffic that is faster- moving, and traffic that is overtaking other traffic to the left. Thus, traffic merging into the leftmost lane from these other lanes is usually required to slow down simply to be able to merge safely into the leftmost lane. This also contributes to the risk of traffic congestion.

It is an object of the invention to ameliorate disadvantages of the prior art, and/or to propose an alternative traffic intersection configuration, and/or to provide for other features relating to traffic control and traffic control infrastructure.

DISCLOSURE OF INVENTION

According to a first aspect of the invention there is provided a traffic control intersection comprising: a first road having a plurality of substantially parallel first road lanes for directing road vehicles in a first direction along the first road; a second road running crosswise relative to the first road, the second road having a plurality of substantially parallel second road lanes for directing road vehicles in a second direction along the second road, the second direction extending at least partially leftward relative to the first direction, the second road further having a plurality of third road lanes being substantially parallel to one another and to the second road lanes along the second road, for directing road vehicles in a third direction along the second road, the third direction being opposite to the second direction in relation to the second road and extending at least partially rightward relative to the first direction; a first pathway interconnecting a lane, being the leftmost one of said first lanes in relation to said first direction at a position at which the first pathway connects to the first road, with a lane, being the leftmost one of said second lanes in relation to said second direction at a position at which the first pathway connects to the second road; and a second pathway interconnecting a lane, being the rightmost one of said first lanes in relation to said first direction at a position at which the second pathway connects to the first road, with a lane, being the rightmost one of said third lanes in relation to said third direction at a position at which the second pathway connects to the second road, the second pathway crossing at least one of said second lanes and being at a different elevation to the at least one second lane where it crosses it, to enable road vehicles to travel from said rightmost first lane to said rightmost third lane without travelling on the at least one second lane.

In a preferred embodiment, the first road defines a plurality of fourth road lanes, which are substantially parallel to one another and to the first road lanes, for directing road vehicles in a fourth direction along the first road, the fourth direction being opposite to the first direction relative to said first road.

Preferably, the intersection comprises a third pathway interconnecting a lane, being the leftmost one of said second lanes in relation to said second direction at a position at which the third pathway connects to the second road, to a lane, being a leftmost one of said fourth lanes in relation to the fourth direction at a position at which the third pathway connects to the first road.

Preferably, also, the intersection comprises a fourth pathway interconnecting a lane, being the rightmost one of said third lanes in relation to said third direction at a position at which the fourth pathway connects to the second road, to a lane, being the rightmost one of said fourth lanes in relation to the fourth direction at a position at which the fourth pathway connects to the first road, the fourth pathway crossing at least one of said second lanes and being at a different elevation to the at least one second lane where it crosses it, to enable road vehicles to travel from said rightmost third lane to said rightmost fourth lane without travelling on the at least one second lane. In a preferred embodiment, the intersection comprises a third road running crosswise relative to the second road, the third road defining a plurality of substantially parallel fifth along the third road, the sixth direction being opposite to the fifth direction in relation to said third road.

In a preferred embodiment, the intersection comprises a plurality of said first roads and a plurality of said third roads. Preferably, the intersection comprises three said first roads and three said third roads.

Then, in a preferred embodiment, for each particular first road having, in relation to its first direction, another first road on its left hand side, the intersection further comprises a pathway interconnecting a lane, being the leftmost one of the first lanes of said particular first road in relation to the first direction pertaining to that first road at a position at which that pathway connects to that first road, with a lane, being the leftmost one of the fourth lanes of said other first road in relation to said fourth direction pertaining to said other first road at a position at which that pathway connects to said other first road.

Then also, in a preferred embodiment, for each particular first road having, in relation to its first direction, another first road on its right hand side, the intersection further comprises a pathway interconnecting a lane, being the rightmost one of the first lanes of said particular first road in relation to the first direction pertaining to that first road at a position at which that pathway connects to that first road, with a lane, being the rightmost one of the fourth lanes of said other first road in relation to said fourth direction pertaining to that other first road at a position at which that pathway connects to said other first road.

Then also, in a preferred embodiment, for each particular third road having, in relation to its sixth direction, another third road on its left hand side, the intersection further comprises a pathway interconnecting a lane, being the leftmost one of the sixth lanes of said particular third road in relation to the sixth direction pertaining to that third road at a position at which that pathway connects to that third road, with a lane, being the leftmost one of the fifth lanes of said other third road in relation to said fifth direction pertaining to said other third road at a position at which that pathway connects to said other third road.

Then also, in a preferred embodiment, for each particular third road having, in relation to its sixth direction, another third road on its right hand side, the intersection further comprises a pathway interconnecting a lane, being the rightmost one of the sixth lanes of said particular third road in relation to the sixth direction pertaining to that third road at a position at which that pathway connects to that third road, with a lane, being the rightmost one of the fifth lanes of said other third road in relation to said fifth direction pertaining to that other third road at a position at which that pathway connects to said other third road.

In one preferred embodiment, the third road is a continuation of the first road, with the fifth lanes being continuations of the first lanes, the sixth lanes being continuations of the fourth lanes, the first direction being the fifth direction and the fourth direction being the sixth direction.

Preferably, the intersection comprises a fifth pathway interconnecting a lane, being the leftmost one of said third lanes in relation to said third direction at a position at which the fifth pathway connects to the second road, to a lane, being the leftmost one of said fifth lanes in relation to said fifth direction at a position at which the fifth pathway connects to the third road.

Preferably, also, the intersection comprises a sixth pathway interconnecting a lane, being the rightmost one of said second lanes in relation to said second direction at a position at which the sixth pathway connects to the second road, to a lane being the rightmost one of said fifth lanes in relation to the fifth direction at a position at which the sixth pathway connects to the third road, the sixth pathway crossing at least one of said third lanes and being at a different elevation to the at least one third lane where it crosses it, to enable road vehicles to travel from said rightmost second lane to said rightmost fifth lane without travelling on the at least one third lane.

Preferably, also, the intersection comprises a seventh pathway interconnecting a lane, being the leftmost one of said sixth lanes in relation to said sixth direction at a position at which the seventh pathway connects to the third road, to a lane, being the leftmost one of said third lanes in relation to the third direction at a position at which the seventh pathway connects to the second road.

Preferably, also, the intersection comprises an eighth pathway interconnecting a lane, being the rightmost one of said sixth lanes in relation to said sixth direction at a position at which the eighth pathway connects to the third road, to a lane, being the rightmost one of said second lanes in relation to the second direction at a position at which the eighth pathway connects to the second road, the eighth pathway crossing at least one of said third lanes and being at a different elevation to the at least one third lane where it crosses it, to enable road vehicles to travel from said rightmost sixth lane to said rightmost second lane without travelling on the at least one third lane.

In a preferred embodiment, the intersection comprises a traffic roundabout, the roundabout constituting at least two of said pathways.

Preferably, the intersection comprises a central zone circumscribed by the roundabout and a chamber within the central zone, beneath the roundabout. The chamber preferably includes a water storage tank.

In a preferred embodiment, at least one of the roads interconnected by the roundabout has at least one lane which passes over the roundabout whereby a utility space is at least partly defined by and between the roundabout and the road passing over the roundabout.

Preferably the intersection further comprises, in the utility space, a building for accommodating occupants.

According to a second aspect of the invention there is provided a traffic control intersection arrangement comprising: a traffic control intersection according to the first aspect of the invention; and a pedestrian walkway structure for spanning the intersection, the walkway structure having a walkway spaced above, and extending across, the intersection, first access means extending between a first position adjacent the intersection and the walkway, for enabling pedestrians to move from the first position to the walkway, and second access means extending between the walkway and a second position adjacent the intersection, for enabling pedestrians to move from the walkway to said second position, wherein the walkway includes an inner section disposed above the intersection and an outer section, the inner section being selectively detachable from the outer section and adapted to be raised relative to the outer section.

According to a third aspect of the invention there is provided a pedestrian walkway structure for spanning a roadway, the walkway structure comprising: a walkway spaced above, and extending across, the roadway; first access means extending between a first position adjacent the roadway and the walkway, for enabling pedestrians to move from the first position to the walkway; and second access means extending between the walkway and a second position adjacent the roadway, for enabling pedestrians to move from the walkway to said second position; wherein the walkway includes an inner section disposed above the roadway and an outer section, the inner section being selectively detachable from the outer section and adapted to be raised relative to the outer section.

Preferably, each access means includes at least one of a stairway, an escalator, a ramp, and a lift.

Definitions and interpretation

The invention and its various embodiments is defined and described herein in relation to roads, roadways and the like which apply the rule in which vehicles travel on the left in relation to the direction in which they are travelling, that is, in which oncoming traffic is to their right. This is the rule, for example, in Australia and Great Britain. However, the invention (including the invention as claimed) is not limited to being applied to this rule; indeed it is equally applicable, mutatis mutandis (subject to making the necessary changes), in relation to roads, roadways and the like which apply the rule in which vehicles travel on the right in relation to the direction in which they are travelling, that is, in which on-coming traffic is to their left. This is the rule, for example, in the USA, France and Italy. Accordingly, the invention is to be understood as also including cases where each reference to left, leftmost, left hand side, and the like, is substituted by corresponding references to right, rightmost, right hand side, and the like and vice versa.

Where reference is made herein to a "road", this includes a road arrangement having one or more lanes for directing traffic in one direction and one or more other lanes for directing traffic in a direction which is opposite to the one direction, where the lanes for directing traffic in these two directions are disposed on separate physical structures to each other with or without a gap between these structures.

In this specification, unless the context clearly indicates otherwise, the word "comprising" is not intended to have the exclusive meaning of the word (such as "consists only of") but rather has the non-exclusive meaning, in the sense of "including at least". The same applies, with corresponding grammatical changes, to other forms of the word such as "comprise", "comprises", etc.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a schematic representation, in plan view, of a traffic control intersection according to an embodiment of the invention;

Figure 2 is a schematic representation, in plan view, of a traffic control intersection similar to that of Figure 1 , but with the angle between intersecting roads being different to that of Figure 1 ;

Figure 3 is a schematic representation, in plan view, of a traffic control intersection similar to that of Figure 1 , but with the angle between intersecting roads being different to that of Figure 1 and Figure 2; Figure 4 is a schematic representation, in plan view, of a traffic control intersection similar to that of Figure 1 , but with different relative dimensions of parts of the intersection;

Figure 5 is a schematic representation, in plan view, of a traffic control intersection according to another embodiment of the invention;

Figure 6 is a schematic representation, in plan view, of a traffic control intersection according to yet another embodiment of the invention;

Figure 7 is a schematic representation, in plan view, of a traffic control intersection according to another form of the embodiment of Figure 6; Figure 8 is a schematic representation, in plan view, of a traffic control intersection according to yet another form of the embodiment of Figure 6;

Figure 9 is a schematic representation, in plan view, of a traffic control intersection according to another embodiment of the invention;

Figure 9A is a schematic representation, in plan view, of a traffic control intersection according to yet another embodiment of the invention;

Figure 10 is a schematic representation, in plan view, of a traffic control intersection according to a further embodiment of the invention;

Figure 11 is a schematic representation, in plan view, of a traffic control intersection according to another form of the embodiment of Figure 10; Figure 12 is a schematic representation, in plan view, of a traffic control intersection according to another embodiment of the invention;

Figure 13 is a schematic cross section through a traffic roundabout structure forming part of the embodiment of Figure 10 with part of a walkway added;

Figure 14 is a schematic representation, in plan view, of a pedestrian walkway bridge according to an embodiment of the invention;

Figure 15 is a schematic representation, in plan view, of a road network incorporating traffic control intersections according to embodiments of the invention;

Figure 16 is a schematic representation, in plan view, of a roadway with an accident traffic diversion according to an embodiment of the invention; and Figures 17 to 26 are schematic representations, in plan view, of pedestrian walkway bridges according to different embodiments to that shown in Figure 14, for suiting different road configurations. MODES FOR CARRYING OUT THE INVENTION

In the drawings that follow, where reference is made to a particular pathway being connected to a leftmost or rightmost lane of a particular road at the position where that pathway joins the road, this is to be taken to be so even if not accurately depicted in the relevant drawings.

Embodiment of Figure 1

Referring to Figure 1 , there is shown a traffic control intersection 10, which includes a first road 12 and a second road 14 running crosswise relative to the first road.

The first road 12 has road markings 13 defining a pair of parallel first road lanes 16 for directing road vehicles (not shown) in a first direction 18.

The second road 14 defines, by means of road markings 13, a number of parallel second road lanes 20 for directing road vehicles in a second direction 22. As can be seen, the second direction 22 extends leftward relative to the first direction 18.

The second road 14 further defines, by means of road markings 13, a number of parallel third road lanes 24. These lanes 24, which are parallel to the second lanes 20, are for directing road vehicles in a third direction 26 along the second road 14. The third direction 26 is opposite to the second direction 22 in relation to the second road 14, and extends rightward relative to the first direction 18.

The intersection 10 includes a first pathway 28 which interconnects a lane 30 with a lane 32. The lane 30 is the leftmost one of the first lanes 16 relative to the first direction 18 at the point where the pathway 28 is joined to the first road 12. The lane 32 is the leftmost one of the second lanes 20 in relation to the second direction 22 at the position designated 34 along the road 14 where the pathway 28 joins this road.

The intersection 10 also includes a second pathway 36 which interconnects a lane 38 with a lane 40. The lane 38 is the rightmost one of the first lanes 16 in relation to the first direction 18, at the position at which the pathway 36 joins the road 12. The lane 40 is the rightmost one of the third lanes 24 in relation to the third direction 26, at the position at which the pathway 36 joins the road 14.

The first road 12 also defines a pair of parallel fourth road lanes 42, which are parallel to the first lanes 16. The fourth road lanes 42 are for directing road vehicles in a fourth direction 46 along the first road 12. The fourth direction 46 is opposite to the first direction 18 in relation to the first road 12.

The intersection 10 also includes a third pathway 48, which interconnects a lane 50 with a lane 52. The lane 50 is the leftmost one of the second lanes 20 in relation to the second direction 22, at the position designated 54 along the road 14 at which the pathway 48 joins the road 14. The lane 52 is the leftmost one of the fourth lanes 42 in relation to the fourth direction 46, at the position at which the pathway 48 joins the road 12.

The intersection 10 also includes a fourth pathway 56 which interconnects the lane 40 to a lane 60. The lane 40 is also the rightmost one of the fourth lanes 24 in relation to the third direction 26 at the position at which the pathway 56 joins the road 14. The lane 60 is the rightmost one of the fourth lanes 42 in relation to the fourth direction 46 at the position at which the pathway 56 joins the road 12.

It will be noted that the pathways 36 and 56 extend over the lanes 20. To enable this, these pathways, where they pass over the lanes 20, are in the form of raised bridges with spaces beneath them (not shown) through which vehicles travelling along the lanes 20 can pass.

To enable vehicles to access the raised pathway 56, the lane 40 constitutes a ramp which slopes upwardly (on the left hand side of the position at which the pathway 36 intersects the lane 40 in Figure 1) in the direction 26, from the level of the other lanes 24 to the raised level of the pathway 56.

Similarly, to enable vehicles to continue along the lanes 24 from the raised pathway 36, the lane 40 constitutes a ramp which slopes downwardly (on the right hand side of the position at which the pathway 56 intersects the lane 40 in Figure 1) in the direction 26, from the raised level of the pathway 36 to the level of the other lanes 24.

In addition, to enable the pathways 36 and 56 to join the lanes 38 and 60, these pathways slope downwards from their respective raised positions as mentioned above, at the positions designated 61 , to the lower level of the lanes 38 and 60.

In the case of vehicles travelling along the road 12 in the direction 18, where the drivers of these vehicles wish to turn left into the road 14 so as to proceed in the direction 22, their vehicles must be in the leftmost lane 30 (leftmost in relation to the direction 18). These vehicles can then proceed along the pathway 28 and enter the leftmost lane 32 of the road 14.

Similarly, in the case of vehicles travelling along the road 12 in the direction 18, where the drivers of these vehicles wish to turn right into the road 14 so as to proceed in the direction 26, their vehicles must be in the rightmost lane 38 (rightmost in relation to the direction 18). These vehicles can then proceed along the pathway

36 and enter the rightmost lane 40 of the road 14. These vehicles will then descend along the downward slope of this lane 40 until the level of the other lanes 24 is reached.

In the case of vehicles travelling along the road 14 in the direction 22, where the drivers of these vehicles wish to turn left into the road 12 so as to proceed in the direction 46, their vehicles must be in the leftmost lane 50 (leftmost in relation to the direction 22). These vehicles can then proceed along the pathway 48 and enter the leftmost lane 52 of the road 12 (leftmost in relation to the direction 46).

Similarly, in the case of vehicles travelling along the road 14 in the direction 26, where the drivers of these vehicles wish to turn right into the road 12 so as to proceed in the direction 46, their vehicles must proceed upward along the slope of the rightmost lane 40, and then along the pathway 56 and enter the rightmost lane 60 (rightmost in relation to the direction 46) of the road 12. One important advantage of the intersection 10 according to the above embodiment is that vehicles can proceed from a particular lane in one of the roads 12 or 14 to a corresponding lane in the other one of these roads. Thus, provided that downstream traffic and other conditions permit, this embodiment may assist in enabling vehicles to substantially maintain their speeds, and not to have to slow down to a significant extent, when turning from one of the roads 12 and 14 into the other of these roads.

To further contribute to this capability, in preferred embodiments the pathways 28, 36, 48 and 56 are constructed with suitable cambers to facilitate stability of vehicles travelling along the curves of these pathways.

It will be noted that the pathway 36 exits into the lane 40 upstream of the entry from that lane to the pathway 56. Drivers exiting the pathway 36 into the lane 40 must therefore exercise caution in relation to vehicles already in that lane, including those vehicles which are about to enter the pathway 56. This scenario may be regarded as comparable with a situation in which a driver enters a traffic roundabout (traffic circle). However, the level of risk may be minimised by the ability of vehicles to substantially maintain their speeds as described above, so that the speed of vehicles exiting the pathway 36 into the lane 40 may be well matched to that of vehicles travelling along the lane 40, including those about to enter the pathway 56.

In another embodiment (not shown) to that described above, the pathways 36 and 56 are disposed underneath the lanes 20. To achieve this, these pathways, at those positions, may extend through simple tunnels, and the lanes connecting to these pathways are suitably sloped. The road 14, where it passes over these lanes, may be in the form of a mesh to allow natural light to reach these lanes.

Embodiment of Figure 2

Referring now to Figure 2, there is shown a traffic control intersection 62. Features illustrated in Figure 2 corresponding to features in Figure 1 are denoted by reference numerals which are similar to those in Figure 1 , except that they have the suffix ".2". Except as may be otherwise described, the descriptions in Figure 1 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 2. The intersection 62 is similar to the intersection 10 except that the road 12.2 extends at an angle relative to the road 14.2 which is different to the substantially right angle between the roads 12 and 14 in Figure 1.

Because of this difference in angle, the lengths and curves of the pathways 28.2, 36.2, 48.2 and 56.2 differ from those of the pathways 28, 36, 48 and 56. In particular, it will be noted that the pathway 28.2 is shorter, and has a tighter curve, than the pathway 28, the pathway 36.2 is shorter than the pathway 36, the pathway 48.2 is longer than the pathway 48, and the pathway 56.2 is longer, and has a more gradual curve, than the pathway 56.

Because of these differences in dimensions, the cambers of the pathways 28.2, 36.2, 48.2 and 56.2 may be appropriately different to those of the pathways 28, 36, 48 and 56 to provide stability to vehicles travelling thereon.

It will also be noted that the pathway 56.2 extends over, not just the lanes 20.2, but also partly over the pathway 48.2. Consequently, sufficient space (not shown) is provided beneath the pathway 56.2 for vehicles travelling along the pathway 48.2 to pass through.

Embodiment of Figure 3

Referring now to Figure 3, there is shown a traffic control intersection 64. Features illustrated in Figure 3 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".3". Except as may be otherwise described, the descriptions in Figure 1 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 3.

The intersection 64 is similar to the intersections 10 and 62 except that the road 12.3 extends at an angle relative to the road 14.3 which is different to the angle between the roads 12 and 14 and that between the roads 12.2 and 14.2. Because of this difference in angle, the lengths and curves of the pathways 28.3, 36.3, 48.3 and 56.3 differ from those of the pathways 28, 36, 48 and 56 and the pathways 28.2, 36.2, 48.2 and 56.2. In this embodiment, in particular, it will be noted that the pathway 28.3 is longer, and has a more gradual curve, than the pathways 28 and 28.2, the pathway 36.3 is longer than the pathways 36 and 36.2, the pathway

48.3 is shorter and has a tighter curve than the pathways 48 and 48.2, and the pathway 56.3 is shorter and has a tighter curve than the pathways 56 and 56.2.

Because of these differences in dimensions, the cambers of the pathways 28.3, 36.3, 48.3 and 56.3 may be appropriately different to those of the pathways in Figures 1 and 2, to provide necessary stability to vehicles travelling thereon.

In this embodiment, the pathway 36.3 extends, not just over the lanes 20.3, but also partly over the pathway 28.3. Consequently, sufficient space (not shown) is provided beneath the pathway 36.3 for vehicles travelling along the pathway 28.3 to pass through.

Embodiment of Figure 4

Referring now to Figure 4, there is shown a traffic control intersection 66. Features illustrated in Figure 4 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures but which have the suffix ".4". Except as may be otherwise described, the descriptions in Figure 1 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 4.

The intersection 66 is similar to the intersection 10 except that the pathways 36.4 and

56.4 have greater relative dimensions than the corresponding pathways of Figure 1. It will therefore be noted that both of these pathways 36.4 and 56.4 extend not just over the lanes 20.4, but also over the pathways 28.4. and 48.4. Consequently, sufficient space (not shown) is provided beneath the pathways 36.4 and 56.4 for vehicles travelling along the pathways 28.3 and 48.4, respectively, to pass through. Because of the greater relative dimensions of the pathways 36.4 and 56.4, their curves can be more gradual that those of the pathways 28, 36, 48 and 56. Consequently, the cambers of the pathways 28.4, 36.4, 48.4 and 56.4 may be different to those of the pathways in Figures 1 and 2, to provide necessary stability to vehicles travelling thereon. Indeed, the greater diameter of the pathways 36.4 and 56.4 facilitates faster speeds of vehicles thereon, which in turn permits a higher speed of vehicles entering the pathway 56.4 from the lane 40.4, and higher speed of vehicles exiting the pathway 36.4 to the lane 40.4.

Embodiment of Figure 5

Referring now to Figure 5, there is shown a traffic control intersection 68. Features illustrated in Figure 5 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".5". Except as may be otherwise described, the descriptions in Figure 1 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 5.

One difference is that the pathways 28.5, 36.5, 48.5 and 56.5, instead of being of the bowed shape of the pathways 28, 36, 48 and 56 in Figure 1 , are of the regular, gently curved shape as shown in Figure 5.

Another difference is that the pathway 56.5 extends underneath the lanes 20.5 rather than above them, as is the case of the pathway 56 in relation to the lanes 20 in Figure 1. To achieve this, the lane 40.5, at the position 70 in Figure 5, slopes downwards in the direction 26.5 to join the pathway 56.5. On the other side of the lanes 20.5, at the position 72 in Figure 5, the pathway 56.5 slopes upward to join the lane 60.5.

In the preferred embodiment, the road 14.5 is at ground level, the pathway 56.5 extending as a below-ground recess or tunnel under the lanes 20.5. The pathway 36.5 is in the form of a raised bridge passing over the lanes 20.5 with spaces below (not shown) for vehicles travelling along the lanes 20.5 to pass through.

A further difference is that the lane 40.5 is not continuous but has a break between the start of the pathway 56.5 and the end of the pathway 36.5, at the position designated 74. This break enables that part of the lane 40.5 which joins the pathway 56.5 to slope downwards to join that pathway as described above, and the other part of the lane 40.5 which is joined by the pathway 36.5 to slope downward from the raised level of that pathway, also as described above.

The gentle curved configuration of the pathways 28.5, 36.5, 48.5 and 56.5 may be regarded as a "high speed" configuration when compared with the bowed shape of the pathways 28, 36, 48 and 56 in Figure 1. This is because the gentler curve is more suited to ensuring stability than the more tightly curved bowed shape in Figure 1 , despite the greater centrifugal force that may be induced due to the higher speed of the vehicles travelling along the curved path. Accordingly, an intersection having the configuration of the intersection 68 may be used when the roads 12.5 and 14.5 are relatively high traffic speed roads such as a freeway or high speed arterial road.

Embodiment of Figure 6

Referring now to Figure 6, there is shown a traffic control intersection 76. Features illustrated in Figure 6 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".6". Except as may be otherwise described, the descriptions in Figures 1 and 5 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 6.

The traffic control intersection 76, in addition to those features corresponding to the traffic control intersection 68 of Figure 5, also includes a third road 78 extending crosswise relative to the road 14.6 (and in this embodiment, extending substantially parallel to the road 12.6). The road 78 has road markings 13.6 defining a pair of parallel fifth road lanes 80 for directing road vehicles in a fifth direction 82 along the road. The road 78 also has road markings 13.6 defining a pair of parallel sixth road lanes 84, which are also parallel to the lanes 80, for directing road vehicles in a sixth direction 86 along this road. The direction 86 is opposite to the direction 82 in relation to the road 78.

In this particular embodiment, as the road 78 is parallel to the road 12.6, it will be appreciated that the directions 82 and 86 are the same as the directions 18.6 and 46.6, respectively.

The intersection 76 includes a fifth pathway 88 which interconnects a lane 90 with a lane 92. The lane 90 is the leftmost one of the lanes 24.6 in relation to the direction 26.6 at the position where the pathway 88 joins the road 14.6. The lane 92 is the leftmost one of the lanes 80 in relation to the direction 82 at the position where the pathway 88 joins the road 78.

The intersection 76 also includes a sixth pathway 94 which interconnects a lane 96 with a lane 98. The lane 96 is the rightmost one of the lanes 20.6 in relation to the direction 22.6 at the position where the pathway 94 joins the road 14.6. The lane 98 is the rightmost one of the lanes 80 in relation to the direction 82 at the position where the pathway 94 joins the road 78.

In addition, the intersection 76 includes a seventh pathway 100 which interconnects a lane 102 with the lane 90. The lane 102 is the leftmost one of the lanes 84 in relation to the direction 86 at the position where the pathway 100 joins the road 78.

It will be noted that the lane 90 is not continuous but has a break at the position designated 104 between that part of the lane 90 which joins up with the pathway 88, and that part which is joined by the pathway 100.

The intersection 76 also includes an eighth pathway 106 which interconnects a lane 108 with a lane 110. The lane 108 is the rightmost one of the lanes 84 in relation to the direction 86 at the position where the pathway 106 joins the road 78. The lane 110 is the rightmost one of the lanes 20.6 in relation to the direction 22.6 at the position where the pathway 106 joins the road 14.6.

Correspondingly to the embodiment of Figure 5, in the embodiment shown in Figure 6, the road 14.6 is at ground level, with the pathway 94 extending as a below-ground recess or tunnel under the lanes 24.6. The pathway 106 is in the form of a raised bridge passing over the lanes 24.6 with spaces below (not shown) for vehicles travelling along the lanes 24.6 to pass through.

To achieve this lowered configuration of the pathway 94, the lane 96 is sloped downwards in the direction 22.6 to join the pathway 94, and the lane 98 slopes upward in the direction 82 from the lowered level of the pathway 94 to the level of the other lanes 80.

Similarly, the lane 108 is sloped upwards in the direction 86 to join the pathway 106, and the lane 110 slopes downwards in the direction 22.6 from the raised level of the pathway 106 to the level of the other lanes 20.6.

As in the case of the pathways 28.6, 36.6, 48.6 and 56.6 (and explained in relation to the corresponding pathways 28.5, 36.5, 48.5 and 56.5 of Figure 5), the gentle curved configuration of the pathways 88, 94, 100 and 106 may be regarded as a "high speed" configuration.

Embodiment of Figure 7

Referring to Figure 7, there is shown a traffic control intersection 112. Features illustrated in Figure 7 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".7". Except as may be otherwise described, the descriptions in Figures 5 and 6 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 7. In the intersection 112, instead of there being only a pair of each of the lanes 16.7, 42.7, 80.7 and 84.7 (as is the case with the corresponding lanes in Figure 6), the road markings 13.7 define five of each of these lanes.

The middle three of each of the lanes 16.7 and 42.7 extend underneath the lanes 20.7 and 24.7 so as to join up with, and be integral to, the lanes 80.7 and 84.7, respectively. This is enabled by the roads 12.7 and 78.7 being joined to each other so as to be effectively continuations of each other, so that the joined lanes are also effectively continuations of each other, and so that the directions 18.7 and 46.7 are the directions 82 and 86, respectively.

This configuration enables vehicles travelling along the road 12.7 to continue along the road 78.7, and vice versa.

The intersection 112, in one preferred embodiment, has roadways on four difference levels: the elevation of the road 14.7 at ground level, the raised elevation of the pathways 36.7 and 106.7 passing over the lanes 20.7 and 24.7, respectively, a first lowered elevation being the elevation of the pathways 56.7 and 94.7 passing underneath the lanes 20.7 and 24.7, respectively, and a second lowered elevation being the elevation of the combined roads 12.7. and 78.7.

Embodiment of Figure 8

Referring to Figure 8, there is shown a traffic control intersection 114. Features illustrated in Figure 8 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".8". Except as may be otherwise described, the descriptions in Figure 7 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 8.

The intersection 114 is essentially the same as the intersection 112, except that the pathway 94.8 passes over the lanes 24.8 as well as over the pathways 36.8 and 106.8, and the pathway 56.8 passes over the lanes 20.8 as well as over the pathways 36.8 and 106.8. To achieve this, each of the pathways 94.8 and 56.8, at these locations, are in the form of raised bridges with spaces underneath (not shown) for vehicles travelling along the lanes 20.8 or 24.8, or along the pathways 36.8 and 106.8, to pass through.

In addition, the lane 96.8 slopes upwards in the direction 22.8 to join the pathway 94.8 at its raised level, and then, on the other side of the lanes 24.8, the lane 98.8 slopes downwards in the direction 82.8 to the level of the other lanes 80.8. Similarly, the lane 40.8 slopes upwards in the direction 26.8 to join the pathway 56.8 at its raised level, and then, on the other side of the lanes 20.8, the lane 60.8 slopes downwards in the direction 46.8 to the level of the other lanes 42.8.

Embodiment of Figure 9

Referring now to Figure 9, there is shown a traffic control intersection 116. Features illustrated in Figure 9 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".9". Except as may be otherwise described, the descriptions in Figure 6 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 9.

In Figure 9, instead of having pathways corresponding directly to the pathways 36.6 and 106 of Figure 6, the intersection 116 is provided with a traffic roundabout (traffic circle) 118.

In the preferred embodiment shown, the roads 12.9, 14.9 and 78.9 are at ground level, and the roundabout 118 is at a below-ground level with the lanes 20.9 and 24.9 passing over the roundabout. For the purpose of clarity, in Figure 9 these lanes are depicted partially cut away so as not to be shown at the position where they cross over the roundabout 118. The roundabout 118 is formed, in this embodiment, in an underground tunnel or, alternatively, in a simple recess which may be an excavated recess. Accordingly it will be out of sight of vehicles travelling along the pathways 28.9, 88.9, 100.9 and 48.9. There are two entrances 120 and 122 to the roundabout 118, from the lanes 38.9 and 108.9, respectively, and four exits 124, 126, 128 and 130 from the roundabout to the lanes 110.9, 98.9, 40.9 and 60.9, respectively.

As the roundabout 118 is disposed below the lanes 20.9 and 24.9, the exits 124 and 128 are sloped upwards in the directions 22.9 and 26.9, respectively, to enable vehicles exiting the roundabout via these exits to join up with the lanes 110.9 and 40.9, respectively, so as to reach the level of the other lanes 20.9 and 24.9.

It will be noted that, where the exit 126 joins the lane 98.9, at the position 132 in Figure 9, this lane is the rightmost one of the lanes 80.9 in relation to the direction 82.9. However, where the pathway 94.9 joins up with the road 78.9, at the position 134 in Figure 9, it forms an integral part of a further lane which, at that position 134, constitutes the rightmost one of the lanes 80.9. Accordingly that rightmost lane is designated 98.9'.

Similarly, where the exit 130 joins the lane 60.9, at the position 136 in Figure 9, this lane is the rightmost one of the lanes 42.9 in relation to the direction 46.9. However, where the pathway 56.9 joins up with the road 12.9, at the position 138 in Figure 9, it forms an integral part of a further lane which, at that position 138 constitutes the rightmost one of the lanes 60.9. Accordingly that rightmost lane is designated 60.9'.

To enable the entrances 120 and 122 to extend from the level of the lanes 16.9 and 84.9, respectively, to the lowered level of the roundabout 118, these two lanes slope downwards towards the roundabout.

The entrance 120 to the roundabout 118 and the exit 128, together with that portion of the roundabout between this entrance and exit, serve to direct vehicles from the lane 38.9 to the lane 40.9. Thus, this entrance 120, exit 128 and portion of the roundabout 118, correspond to the pathway 36.6 in Figure 6.

Similarly, the entrance 122 to the roundabout 118 and the exit 124, together with that portion of the roundabout between this entrance and exit, serve to direct vehicles from the lane 108.9 to the lane 110.9. Thus, this entrance 122, exit 124 and portion of the roundabout 118 correspond to the pathway 106 in Figure 6.

Vehicles travelling along the road 78.9 in the direction 86.9 can enter the roundabout 118 via the entrance 122 and exit the roundabout via the exit 130 into the road 12.9. Similarly, vehicles travelling along the road 12.9 in the direction 18.9 can enter the roundabout 118 via the entrance 120 and exit the roundabout via the exit 126 into the road 78.9. The effect of this is therefore as if the roads 12.9 and 78.9 were continuous with each other as in the case of the roads 12.7 and 78.7 in Figure 7.

However, having the roads 12.9. and 78.9 joined in the manner of the corresponding lanes in Figure 7 would require there to be four levels of road, namely those of the road 14.9, the combined road formed by the roads 12.9 and 78.9, the roundabout 118, and the pathways 56.9 and 94.9. However, the fact that the roundabout 118 enables vehicles to travel from the road 12.9 to the road 78.9 and vice versa as if these roads were continuous with each other avoids the need for these two roads to be joined in the manner in which the roads 12.7 and 78.7 in Figure 7 are joined to each other. Thus only three levels are required.

The configuration of Figure 6 also has three levels, although in the absence of a roundabout corresponding to the roundabout 118, vehicles cannot travel from the road 12.6 to the road 78.6 and vice versa. Thus the presence of the roundabout provides advantages over the intersections 76 of Figure 6 and 112 of Figure 7.

In addition, the roundabout 118 provides additional versatility as it enables vehicles to exit from the roundabout into the rightmost lanes 110.9 and 40.9 of the road 14.9, and also to enter the roundabout via the rightmost lanes 38.9 and 108.9 of the roads 12.9 and 78.9, respectively.

The substantially circular configuration of the roundabout is of a relatively large diameter and therefore permits vehicles travelling thereon to travel at a speed which is not overly low. However, it is not a configuration which permits as much vehicle stability, and hence as high speeds, as the gentle, curved configurations of the pathways 28.9, 88.9, 100.9 and 48.9, or the pathways 56.9 and 94.9. Therefore even though these pathways may themselves permit "high speed" travel, the intersection 116 as a whole is restricted by the speed permitted by the roundabout 118, and it may therefore be regarded as a "medium speed" configuration.

With numerous entrances to the roundabout 118, it will be appreciated that a vehicle may be entering the roundabout while one or more vehicles are already on the roundabout. This may require that the vehicles on the roundabout 118 give way to vehicles entering the roundabout. For this reason, the roundabout 118 may be referred to as a "turnabout" to suggest the connotation of the respective vehicles on the roundabout taking turns to move past the entrances to the roundabout. The relevant road rules may provide for this by regulating the safe merging of traffic. This may, for example, involve vehicles entering the roundabout 118 being accommodated in the space between two vehicles already on the roundabout.

Embodiment of Figure 9A

Referring now to Figure 9A, there is shown a traffic control intersection 200. Features illustrated in Figure 9A corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".99". Except as may be otherwise described, the descriptions in Figure 9 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 9A.

The intersection 200 is substantially the same as the intersection 116 of Figure 9, except for the presence of a further road 202 and other features relating to the presence of this further road. It will be recalled that the roads 12 and 14 in Figure 1 were described as a "first" road and a "second" road respectively, and the road 78 in

Figure 6 was described as being a "third" road. In this specification for the purposes of consistency, the road 202 may be regarded as a further "third" road in addition to the third road 78.99.

The road 202 has road markings 13.99 defining traffic lanes 204 for directing vehicles in a direction 206, and lanes 208 for directing vehicles in a direction 210 which is opposite to the direction 206 in relation to the road 202. The intersection 200 includes a pathway 212 which interconnects the lane 90.99 with a lane 214. The lane 214 is the leftmost one of the lanes 204 in relation to the direction 206 at the position at which the pathway 212 joins the road 202.

The intersection 200 includes another pathway 216 which interconnects a lane, being the rightmost one of the lanes 20.99 in relation to the direction 22.99 with a lane 218. This rightmost one of the lanes 24.99 is the rightmost lane at the position at which the pathway 216 joins the road 14.99, although the lane designated 96.99 is the rightmost lane at the position at which the pathway 94.99 joins the road 14.99. Hence, the rightmost lane at the position at which the pathway 216 joins the road 14.99 is designated 96.99'. The lane 218 is the rightmost one of the lanes 204 in relation to the direction 206 at the position at which the pathway 216 joins the road 202.

The intersection 200 includes an exit 220 from the roundabout 118.99. This exit 220 interconnects the roundabout 118.99 to a lane which is the rightmost one of the lanes 204 at the position at which the exit 220 joins the road 200. As the lane 218 is the rightmost one of the lanes 204 at the position where the pathway 216 joins the road 200, the rightmost lane at the position at which the exit 220 joins this road is designated 218'.

The intersection 200 includes a further pathway 224 which interconnects a lane 226 with a lane which is the leftmost one of the lanes 80.99 at the position where the pathway 224 joins the road 78.99. The leftmost one of the lanes 80.99 at the position where the pathway 88.99 joins the road 78.99 is designated 92.99. Hence, the leftmost one of the lanes 80.99 at the position where the pathway 224 joins this road is designated 92.99'. The lane 226 is the leftmost one of the lanes 208 in relation to the direction 210 at the position at which the pathway 224 joins the road 202.

The intersection 200 includes a pathway 228 leading to an entrance 230 to the roundabout 118.99. This pathway 228 interconnects a lane 232 with the entrance 230. The lane 232 is the rightmost one of the lanes 208 in relation to the direction 210. As can be seen in Figure 9A, the pathway 228 is curved, and extends underneath the pathways 216 and 88.99.

The presence of the road 202 as shown in Figure 9A illustrates the versatility of the invention in incorporating many connecting roads as part of the intersection. This is further illustrated below in relation to the embodiment of Figure 12.

Embodiment of Figure 10

Referring now to Figure 10, there is shown a traffic control intersection 140. Features illustrated in Figure 10 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".10". Except as may be otherwise described, the descriptions in Figure 9 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 10.

The intersection 140 is substantially the same as the intersection 116 of Figure 9, except that there are no pathways directly corresponding to the pathways 56.9 and 94.9, and that the roundabout 118.10 has two entrances in addition to the entrances 120.10 and 122.10, these being entrances 142 and 144.

The entrance 142 to the roundabout 118.10 and the exit 130.10, together with that portion of the roundabout between this entrance and exit, serve to direct vehicles from the lane 40.10 to the lane 60.10. Thus, this entrance 142, exit 130.10 and portion of the roundabout 118.10 correspond in effect to the pathway 56.9 in Figure 9.

Similarly, the entrance 144 to the roundabout 118.10 and the exit 126.10, together with that portion of the roundabout between this entrance and exit, serve to direct vehicles from the lane 96.10 to the lane 98.10. Thus, this entrance 144, exit 126.10 and portion of the roundabout 118.10 correspond in effect to the pathway 94.9 in Figure 9. In the preferred embodiment shown, the roads 12.10, 14.10 and 78.10 are at ground level, and the roundabout 118.10 is at a below-ground level with the lanes 20.10 and 24.10 passing over the roundabout. For the purpose of clarity, in Figure 10 these lanes are depicted partially cut away so as not to be shown at the position where they cross over the roundabout 118.10. The roundabout 118.10 is formed, in this embodiment, in an underground tunnel. Accordingly it will be out of sight of vehicles travelling along the pathways 28.10, 88.10, 100.10 and 48.10.

As the roundabout 118.10 is disposed below ground level, the lanes 38.10, 40.10 (on the left hand side of the roundabout in Figure 10), 108.10 and 96.10 slope downwards to the entrances 120.10, 142, 122.10 and 144, respectively to the roundabout. The lanes 60.10, 110.10, 98.10 and 40.10 (on the right hand side of the roundabout 118.10 in Figure 10) slope upwards from the relevant exits from the roundabout.

The pathways 56.9 and 94.9 in Figure 9 had to be at an elevation above the lanes 20.9 and 24.9 to pass over these lanes, and accordingly, three different road elevations were required. The omission of directly corresponding pathways in the intersection 140 of Figure 10, due to the configuration of the roundabout 118.10, serves as an advantage as it requires only two separate road elevations.

On the other hand, the pathways 56.9 and 94.9 of the embodiment of Figure 9 were of a gentle, curved configuration, and hence of a "high speed" nature as described above, while the roundabout 118.10 is of a similar circular configuration to the roundabout 118.9 in Figure 9. As mentioned in relation to Figure 9, while the roundabout 118.10 is of a relatively large diameter and therefore permits vehicles travelling thereon to travel at a speed which is not overly low, it is not a configuration which permits as much vehicle stability, and hence equally high speeds, as the configuration of the pathways 56.9 and 94.9 of Figure 9. Therefore the intersection 140 as a whole is restricted by the speed permitted by the roundabout 118.10, and it may therefore be regarded as a "medium speed" configuration. Embodiment of Figure 11

Referring now to Figure 11 , there is shown a traffic control intersection 146. Features illustrated in Figure 11 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".11". Except as may be otherwise described, the descriptions in Figure 10 of corresponding features are to be taken as being equally applicable to the embodiment of Figure 11.

The intersection 146 is substantially the same as the intersection 140 of Figure 10, except that instead of there being only a pair of each of the lanes 16.11 , 42.11 , 80.11 and 84.11 (as is the case with the corresponding lanes in Figure 10), there are five of. each of these lanes, demarcated by the road markings 13.11.

In the preferred embodiment shown, the road 14.11 is at ground level. The middle three of each of the lanes 16.11 and 42.11 extend underneath the road 14.11 so as to join up with, and be integral to, the lanes 80.11 and 84.11 , respectively. This is enabled due to the roads 12.11 and 78.11 being joined to each other so that they are effectively continuations of each other, and so that the joined lanes are also effectively continuations of each other, and so that the directions 18.11 and 46.11 are the directions 82.11 and 86.11, respectively.

Thus, vehicles travelling along the road 12.11 in the direction 18.11 can continue along the road 78.11, and those travelling along the road 78.11 in the direction 86.11 can continue along the road 12.11 , either via the roundabout 118.11 as described above in relation to Figure 9, or simply by continuing in on the respective road itself.

The roundabout 118.11 extends below these joined lanes, that is, at an elevation below the level of the roads 12.11 and 78.11.

Embodiment of Figure 12

Referring now to Figure 12, there is shown a traffic control intersection 700. Features illustrated in Figure 12 corresponding to features in the previous figures are denoted by reference numerals (or numeral prefixes) which are similar to those in the previous figures, but which have the suffix ".12". Except as may be otherwise described, the descriptions in Figure 9A of corresponding features are to be taken as being equally applicable to the embodiment of Figure 12.

Relative to the intersection 200 of Figure 9A, the intersection 700 includes three further roads, being the roads 702, 704 and 706. Just as the road 78 in Figure 6 was described as being a further "third" road, so too can the road 704 in Figure 12 be described as a further "third" road in addition to the third road 78.12. Similarly, for the purpose of consistency in this specification, each of the roads 702 and 706 may be regarded as a further "first" road in addition to the first road 12.12.

The road 702 has road markings 13.12 defining lanes 708 for directing vehicles in a direction 710 and lanes 712 for directing vehicles in a direction 714 which is opposite to the direction 710 in relation to the road 702.

The intersection 700 includes the following pathways in relation to the road 702:

• a pathway 716 leading from the leftmost one of the lanes 708 in relation to the direction 710 at the position where the pathway joins the road 702, to the leftmost one of the lanes 20.12 in relation to the direction 22.12 at the position where the pathway joins the road 14.12;

• a pathway 718 leading from the rightmost one of the lanes 708 in relation to the direction 710 at the position where the pathway joins the road 702, to the roundabout 118.12;

• a pathway 720 leading from the rightmost one of the lanes 24.12 in relation to the direction 26.12 at the position where the pathway joins the road 14.12 to the rightmost one of the lanes 712 in relation to the direction 714 at the position where the pathway joins the road 702; • a pathway 722 leading from the roundabout 118.12 to the rightmost one of the lanes 712 in relation to the direction 714 at the position where the pathway joins the road 702;

• a pathway 724 leading from the leftmost one of the lanes 20.12 in relation to the direction 22.12 at the position where the pathway joins the road 14.12 to the leftmost one of the lanes 712 in relation to the direction 714 at the position where the pathway joins the road 702; and

• a pathway 726 leading from the leftmost one of the lanes 16.12 in relation to the direction 18.12 at the position where the pathway joins the road 12.12 to the leftmost one of the lanes 712 in relation to the direction 714 at the position where the pathway joins the road 702.

The road 704 has road markings 13.12 defining lanes 728 for directing vehicles in a direction 730 and lanes 732 for directing vehicles in a direction 734 which is opposite to the direction 730 in relation to the road 704.

The intersection 700 includes the following pathways in relation to the road 704:

• a pathway 736 leading from the leftmost one of the lanes 728 in relation to the direction 730 at the position where the pathway joins the road 704, to the leftmost one of the lanes 24.12 in relation to the direction 26.12 at the position where the pathway joins the road 14.12;

• a pathway 738 leading from the rightmost one of the lanes 728 in relation to the direction 730 at the position where the pathway joins the road 704, to the roundabout 118.12;

• a pathway 740 leading from the rightmost one of the lanes 20.12 in relation to the direction 22.12 at the position where the pathway joins the road 14.12 to the rightmost one of the lanes 732 in relation to the direction 734 at the position where the pathway joins the road 704; • a pathway 742 leading from the roundabout 118.12 to the rightmost one of the lanes 732 in relation to the direction 734 at the position where the pathway joins the road 704;

• a pathway 744 leading from the leftmost one of the lanes 24.12 in relation to the direction 26.12 at the position where the pathway joins the road 14.12 to the leftmost one of the lanes 732 in relation to the direction 734 at the position where the pathway joins the road 704; and

• a pathway 746 leading from the leftmost one of the lanes 84.12 in relation to the direction 86.12 at the position where the pathway joins the road 78.12 to the leftmost one of the lanes 732 in relation to the direction 734 at the position where the pathway joins the road 704.

The road 706 has road markings 13.12 defining lanes 750 for directing vehicles in a direction 752 and lanes 754 for directing vehicles in a direction 756 which is opposite to the direction 752 in relation to the road 706.

The intersection 700 includes the following pathways in relation to the road 706:

• a pathway 758 leading from the leftmost one of the lanes 750 in relation to the direction 752 at the position where the pathway joins the road 706, to the leftmost one of the lanes 42.12 in relation to the direction 46.12 at the position where the pathway joins the road 12.12;

• a pathway 760 leading from the leftmost one of the lanes 750 in relation to the direction 752 at the position where the pathway joins the road 706, to the leftmost one of the lanes 20.12 in relation to the direction 22.12 at the position where the pathway joins the road 14.12;

• a pathway 762 leading from the rightmost one of the lanes 750 in relation to the direction 752 at the position where the pathway joins the road 706, to the roundabout 118.12; • a pathway 764 leading from the rightmost one of the lanes 24.12 in relation to the direction 26.12 at the position where the pathway joins the road 14.12 to the rightmost one of the lanes 754 in relation to the direction 756 at the position where the pathway joins the road 706;

• a pathway 766 leading from the roundabout 118.12 to the rightmost one of the lanes 754 in relation to the direction 756 at the position where the pathway joins the road 706; and

• a pathway 768 leading from the leftmost one of the lanes 20.12 in relation to the direction 22.12 at the position where the pathway joins the road 14.12 to the leftmost one of the lanes 754 in relation to the direction 756 at the position where the pathway joins the road 706.

The intersection 700 illustrates the versatility of the invention in being adaptable to intersections with large numbers of connecting roads.

Embodiment of Figure 13

Referring to Figure 13, there is shown a cross section through the intersection 140 in Figure 10, along the section line XIII-XIII.

The roundabout 118.10 extends in a circular configuration as shown in Figure 10, and circumscribes a circular central zone 401. The central zone 401 has a central axis 404.

As described above in relation to Figure 10, the roundabout 118.10 is below the level of the road 14.10, the latter being at ground level. Accordingly, the central zone 401 is also below-ground, with the roundabout 118.10 extending through a tunnel. The roundabout 118.10 and central zone on the one hand, and the road 14.10 on the other hand, partly define, between them, a central area 402. It will be appreciated that, because the roundabout 118.10 is below-ground, the central area 402 is recessed into the ground (substratum). That part of the road 14.10 extending over the central area 402 is constituted by a steel covering mesh 406. The mesh 406 is supported by a number of beams 408 (only one of which is shown in Figure 13). The beams 408 extend across the central area 402 and are joined to an inner surface of a wall structure 410 which extends in a circular configuration around the central area. In the embodiment shown, the wall structure 410 is part of the ground in which the central area 402 is recessed. In one preferred embodiment, the surface of the wall structure 410 is of an attractive natural appearance.

The sloped orientation of the lanes 96.10 and 110.10, where they join the entrance 144 to, and exit 124 from, the roundabout 118.10, respectively, can be clearly seen in Figure 13.

Below the roundabout 118.10 is a chamber occupied by water storage tank 418. A body of collected water 420 is shown in the tank 418. The ceiling 422 of the tank 418 is provided with beams 424 (only one of which is shown in Figure 13). The beams 424 extend across the tank 418 and are secured to an inner surface of a wall 426 of the tank. The beams 424 provide reinforcement to the roundabout 118.10.

There is provided a central column 428 having an axis corresponding to the central axis 404. The central column 428 provides additional support to the covering mesh 406. In other embodiments (not shown) where the roundabout 118.10 is larger, there may be provided additional columns at various locations about the central axis 404.

The space of the central area 402 can be used for any suitable purpose, depending on the dimensions of the roundabout 118.10. Examples of the types of use to which the central area 402 can be put include accommodation (possibly even housing), a police station, a local emergency service office, a fire brigade station, a first aid centre or mini hospital, an ambulance station, a hostel and so on. Natural light which may be beneficial for these various uses can pass through the mesh 406. The central zone 401 can also be used for other purposes, as required. For example, it can be used to support landscaped areas or gardens, or artificial pondage which may be used for aquaculture.

In other embodiments (not shown), where required, the central area 402 may even be provided with space for vehicle access, and suitably demarcated parking areas.

Typical sub-road services (such as water piping, electricity ducting and so on) that would ordinarily be disposed underneath a road such as the road 14.10 can be configured to extend around the central area 402 so as not to interfere with the uses to which the central area is put.

The water storage tank 418 is for catching storm water. It is envisaged that suitable drainage ducts and pipes (not shown) will be provided from the road 14.10 and the lanes joining up with the entrances to and exits from the roundabout 118.10, to direct the storm water into the tank 418. In addition, water passing through the mesh 406 is also directed in this manner to the tank 418. Suitable filters (not shown) are provided to filter undesirable matter such as refuse and leaves, and prevent this entering the tank 418.

Tunnels and channels (not shown) are provided for directing water from the tank 418 to natural waterways when the tank is full, that is, when the water in the tank reaches a predetermined "full" level.

In one embodiment (not shown), water turbines are provided in these tunnels and channels, so that in times of heavy rainfall, overflow water can actuate the turbines to generate electricity for suitable use within the central area 402.

In addition, outlets (not shown) are provided to enable relevant authorities to tap water from the tank 418 for any relevant purposes, such as fire fighting or irrigation.

It will be appreciated that the mesh 406 forms an integral part of the road surface of the road 14.10, and the mesh is therefore locked into place to prevent undesired lifting thereof due to vehicles driving onto it as they travel along. The open nature of the mesh 406 may also provide for the ventilation of exhaust fumes of vehicles travelling along the roundabout 118.10.

Typically, an intersection such as the intersection 140 is constructed in the location of an existing regular cross-road intersection. Such a regular intersection typically has traffic lights or other suitable means to regulate the flow of traffic through the intersection. In the present embodiment, the construction of the roundabout 118.10, the central area 402, any structures within the central area, and the water tank 418 at such an existing intersection can be performed underneath a portable expandable bridge (such as a Bailey™ bridge) (not shown) that is moved into place before any excavation of the central area takes place. Thus, the bridge can enable traffic to continue to use the existing, regular intersection while the intersection 140 (and the central area 402) is being constructed underneath the bridge.

In such a scenario where a portable bridge is used, suitable temporary traffic lights (having suitable power supplies), which may be incorporated with the bridge, may be used. This may serve to allow the intersection to continue operating as it did before the portable bridge was installed. Such traffic lights are particularly useful where existing traffic lights (which formed part of the existing intersection) are not correctly positioned in relation to the bridge, for example where the bridge surface is raised above the level of the road surface of the existing intersection.

Such a bridge is typically extendable and moveable so that, once the intersection 140 has been installed, the bridge can be moved to other, adjacent, existing intersections to enable new intersections similar to the intersection 140 to be constructed.

It is envisaged that suitable barriers and impact absorption means such as water bladders will be provided adjacent to all walls at which there is a significant risk of vehicle collision and at sharp edges and the like such as those formed by construction spurs.

A pedestrian walkway 420 (not shown in Figure 10) is provided to enable pedestrians to walk over the intersection 140. Such a walkway may be in the form of the walkway described below in relation to Figure 14. The central area 402 and water tank 418 may be omitted in other embodiments of the intersection 140 in which the roundabout 118.10 is not at a below-ground level. In addition, the mesh 406 may be omitted in embodiments where the roundabout 118.10 is other than one level below ground level.

Embodiments of Figure 14 and Figures 17 to 26

Referring to Figure 14, there is shown an overhead pedestrian walkway 300 for use over an intersection. It will be described in relation to the intersection 140 of Figures 10 and 14. Not all of the detail of the intersection 140 is shown in Figure 14.

The walkway 300 is provided with access stairs 302 which extend upwardly to the raised centre 304 of the walkway. This allows pedestrians to climb up to the walkway centre 304, to cross over the intersection 140, and to climb down via the stairs 302 on the other side.

In other embodiments (not shown), the stairs may be replaced by ramps, lifts, or escalators.

The centre 304 of the walkway 300 has a central section 306 which is separated from the remainder of the walkway at joins 308 so as to be detachable to enable it to be lifted away. This facility may be used in the event that abnormally high vehicles, or vehicles having particularly high loads, are required to pass underneath the walkway 300 while travelling along the road 14.10 and are unable to fit thereunder. In this event, the central section 306 can be lifted off the remainder of the walkway 300 to allow the vehicles to pass, whereafter the central section can be replaced.

In one embodiment (not shown), the central section 306 is configured to be removed by a suitably positioned crane. In another embodiment (also not shown), permanently installed hydraulic rams or the like are provided to effect this lifting of the central section 306. To facilitate the removability of the central section 306, that section, or the walkway as a whole, may be of a relatively lightweight material such as aluminium.

The walkway 300 may also be provided with a central access means (not shown) in the form of stairs, a ramp, an escalator or a lift, to allow pedestrians to reach the central area 402 direct from the centre 304 of the walkway and vice versa. This may assist in allowing people to have safe access to the central area 402 without their having to cross the adjacent roads.

In another embodiment (not shown), air turbines are provided beneath the walkway 300. The currents of air caused by vehicles passing along the road 14.10 underneath the walkway 300 can be used to actuate the turbines for generating electric power which can be used for any suitable purpose. In particular, this electric power may be used as required within the central area 402. It is envisaged that the electricity generated may be AC or DC.

In another embodiment (not shown), instead of the walkway extending over the road 14.10, it is disposed underneath that road, but above the roundabout 118.10. The walkway in this embodiment may be suspended from, or integral with, or otherwise joined to and supported by, the structure of the beams 408. The walkway construction in this embodiment includes a wall disposed at the inner side of the walkway in relation to the central area 402, and is preferably of mesh, glass, or another material which allows pedestrians to look into the central area and central zone 401. The walkway is dimensioned and positioned as required, a suitable distance above the roundabout (eg. 2.4 m). It may be round, square, rectangular or of any other suitable shape.

This walkway can be accessed from ramps and/or stairs which extend from suitable positions adjacent to the road 14.10, preferably at ground level.

With reference to Figures 17 to 26, there are shown walkways 800 similar to the walkway 300 described above, but of a variety of different shapes to suit the configuration of the roads and intersections (generally designated 802) that they span. These walkways 800 may be provided with central sections (not specifically indicated) corresponding to the central section 306 and which are separated from the remainders of the respective walkways at joins 801 corresponding to the joins 308, to allow these central sections to be lifted off the remainder of those respective walkways to allow high vehicles or those having high loads to pass, whereafter the central sections can be replaced, in a similar manner to that described in relation to the walkway 300.

Embodiment of figure 15

Referring to Figure 15, there is shown a diagram of a road network layout 500, showing numerous intersections between different roads which cross one another at intersections according to the various embodiments of the invention as described in Figures 1 to 12. These intersections may be used to channel vehicles without the need for them to stop at conventional traffic intersections involving, for instance, traffic lights or stop signs.

For example, using such intersections, a vehicle could travel from the position D along the road 502 to the intersection 504, turn left into the road 506 and then right at the intersection 508 into the road 510.

In this embodiment, the roads 502 and 506 are each in the form of a freeway while the road 510 is in the form of a smaller arterial road. As the traffic moving along the roads 502 and 506 is relatively fast moving, a suitable "high speed" intersection is appropriate for channelling such vehicles from the road 502 into the road 506. However, the road 510, being a smaller arterial road, is suitable for carrying vehicles at slower speeds, and therefore a "medium speed" intersection will suffice, as the traffic along the road 506 must slow down to some extent before entering the road 510.

Accordingly, in relation to the intersection 504 in the embodiment of Figure 15, the road 502, intersection 504, and road 506 correspond to the road 14.8, intersection 114 (including the pathway 48.8) and road 12.8, respectively, of Figure 8, with the traffic directions for the route in question corresponding to the directions 22.8 and 46.8. Similarly, in relation to the intersection 508, a "medium speed" intersection will suffice such as the intersection 116 of Figure 9. Accordingly, the combination of the road 506, intersection 508 and road 510 correspond to the road 12.9, intersection 116 and road 14.9, respectively, with the traffic directions for the route in question corresponding to the directions 18.9 and 26.9. It will be appreciated that travelling in this manner involves travelling along a roundabout corresponding to the roundabout 118.

Embodiment of Figure 16

The embodiment of the invention in Figure 16 relates to a situation in which there is a vehicle accident on a multi-lane roadway 600 having a number of lanes for directing traffic in one direction 602 along the roadway, and a number of further lanes on another side of a road centre barrier 604, for directing traffic in an opposite direction 606 along the roadway. Indeed, the embodiment of the invention is for a situation where the accident affects the traffic in that one direction 602.

In such a situation, it is important to avoid, as far as possible, traffic congestion adjacent to the site 608 of the accident. Such traffic congestion is typically caused because, firstly, such accidents typically block one or more of the lanes channelling traffic in the one direction 602, and because vehicle drivers have a natural curiosity of accident sites which causes them to drive particularly slowly in order to look at the accident scene. This traffic congestion is disadvantageous and possibly even dangerous, both in relation to the vehicles forming part of the congestion itself, and because the congestion can obstruct and hinder rescue operations at the accident site 608.

To avoid or minimise such problems, a three-prong approach can be used to manage such accident sites 608. This involves: (1) minimising the amount of traffic passing the accident site 608; (2) preventing vehicle drivers of those vehicles passing the accident site 608 from seeing that site; and (3) having the traffic that passes the accident site move as fast as reasonably practicable away from the site. To minimise the amount of traffic passing the accident site 608, traffic moving towards the accident site along the roadway 600 is redirected, at the closest intersections on either side of the accident site, to alternative routes. This is illustrated in Figure 16 in relation to the closest intersection which is generally designated 610, with the traffic moving towards the accident site 608 in the direction 606 being rerouted in the direction 612.

To prevent vehicle drivers of those vehicles passing the accident site 608 from seeing that site, non-transparent screens (not shown) are erected around the site. The erection of such screens may be performed by dedicated screen units of the police or other authorities in attendance at the accident site 608. Indeed, such units may use vehicles provided with safety cones and portable extendable screens, which may be despatched to the accident site 608 together with other emergency vehicles.

To have the traffic which passes the accident site 608 move as fast as reasonably practicable away from the site, a slip lane can be formed adjacent to the accident site for directing traffic in the same direction 602 as that in which it would have travelled along the lanes blocked by the accident. However, a key aspect of this is that the traffic is ordered, by authorities attending the scene or suitable road signage, to speed up rather than to slow down. This involves either completely suspending speed limits, or establishing higher, temporary accident-scene speed limits.

In the event that there is sufficient space for such a slip lane on the same side of the road centre barrier 604 as the accident site 608, the erected screens can themselves be used to define at least part of this slip lane. However, if there is insufficient space on that side of the centre barrier 604, then the slip lane can be formed on the other side of the barrier, in what was, before the establishment of the slip lane, an oncoming lane. Such a slip lane is designated 616 in Figure 16.

To enable this, the centre barrier 604 is provided with a series of gaps 618 along its length. Respective gaps 618 are angled as shown in Figure 16 to facilitate rapid movement of vehicles travelling in the direction 602 from the side of the barrier 604 on which they are travelling to the other side of the barrier. Similarly, other respective gaps 618 are angled differently, to facilitate rapid movement of vehicles travelling in the direction 606 from the side of the barrier 604 on which they are travelling to the first-mentioned side of the barrier. In the preferred embodiment as shown in Figure 16, these differently angled gaps are positioned alternately to each other. For the purpose of illustration, the gap 618 that enables traffic to bypass the accident site 608 along the slip lane 616, is designated 618' in Figure 16.

Diverting traffic to a slip lane which is constituted by one of the oncoming lanes, as described above, reduces the effective number of oncoming lanes. To enable traffic travelling along the oncoming lanes to pass the accident site 608 as quickly as it would have in the absence of the slip lane, the speed limits in the oncoming lanes may be raised to higher, temporary accident-scene speed limits or suspended completely.

These gaps 618 can also be used in the event that there are no sufficiently close intersections (such as the intersection 610) at which traffic can be rerouted. In this event, the gaps 618 can be used to enable vehicles approaching the accident site 608 to perform U-turns as illustrated at 620, via the particular gap 618 which is designated 618". Such vehicles thus turn via the gap 618" onto the opposite side of the centre barrier 604, so as to return in the direction from which they have arrived.

The gaps 618 may also be used by emergency vehicles which can approach the accident site 608 from the other side of the centre barrier 604 (in the oncoming lanes) and then move, via a gap, to the side of the barrier on which the accident site is located.

Depending on local conditions and requirements, the rerouting of traffic at the closest intersections may be performed until the accident site 608 has been completely cleared, or just until traffic density has dropped sufficiently to allow all of the traffic heading in the direction 602 of the blocked lanes to pass safely via the slip lane 616. Alternative embodiments and advantages of the invention

Although the invention is described in relation to particular embodiments above, those skilled in the art will appreciate that it is not limited to those particular embodiments, but may be embodied in many other forms.

In the various embodiments described above, various relative elevations of the roadways, pathways and roundabouts are shown. However, the arrangement of the different elevations may be different. For instance, instead of a roundabout being below a main road, it may be above it. In this case suitable differences will apply to the configurations and slopes of the lanes and pathways leading to and from the roundabout. The relative elevations of the various roadways, pathways and roundabouts may depend on the requirements of the particular intersection and its location - such as the topography or even aesthetics thereof. For example, if having a roundabout positioned above a ground-level road would be particularly unappealing aesthetically in the scenario of a particular intersection, the roundabout may be positioned, instead, at a position below ground-level, that is, below the level of the road.

Another factor which can influence the relative elevations of the various roadways, pathways and roundabouts is the desire to have accesses to high speed roads slope downwards towards those roads, and exits from those roads slope upwards from those roads. For example, a pathway serving to direct traffic onto a freeway, if it sloped downwards towards the freeway, would facilitate acceleration of vehicles to assist them to achieve the relatively high travelling speed of that freeway. Similarly, a pathway serving to direct traffic from a freeway, if it sloped upwards away from the freeway, would facilitate deceleration of vehicles from the relatively high speed of the freeway to the relatively low speed of the road to which the pathway leads.

Typically, a roundabout only has one traffic lane. If this cannot cope with the relevant traffic volume, more than one roundabout can be provided, and the roundabouts can be positioned one above another. Roundabouts, even those having one traffic lane, can be provided with emergency stop bays, lanes or areas.

All roads, pathways and roundabouts can be cambered to suit the needs of the expected traffic, to facilitate vehicle stability. This is particularly so where turns or curves are involved and which induce centrifugal forces in the vehicles. Suitable cambers may also be provided for other purposes, for example to facilitate rolling of vehicles into emergency stop bays in the event of vehicle engine malfunction.

In addition, it is envisaged that all pathways will be of suitable length to enable vehicles travelling thereon to adjust their speeds from that which is suitable for the roads from which the pathways lead to that of the roads to which the pathways lead.

The invention essentially enables a vehicle to make a left turn from the leftmost lane of the road on which the vehicle is travelling to the leftmost lane of a cross road, and to make a right turn from the rightmost lane of the road on which the vehicle is travelling to the rightmost lane of the cross road.

Accordingly, the effect is almost as if the vehicle were simply continuing along the same road. In particular, because a leftmost lane is generally a "slow" lane and a rightmost lane is a "fast" lane, the invention allows such a vehicle to turn left and right from the road on which it is travelling into a cross road and to continue in that cross road in a lane which corresponds, speed wise, to the lane from which the vehicle turns. This avoids the need, in conventional intersections, for all vehicles wishing to turn left or right into the cross road to be in the leftmost lane of the road from which they are making the turn.

In addition, the pathways that lead from the road from which the vehicle is turning to the cross road, where they cross other lanes of the first-mentioned road, are at different elevations to these lanes, and therefore pass over or under these lanes. This means that the need for traffic lights, stop signs and the like is avoided, and the vehicle can make its turn without stopping, and without even having to slow down significantly provided that this is permitted by the nature of the curve, the camber of the pathway, and traffic conditions. It is envisaged that this will significantly assist in reducing traffic congestion, and decreasing travel durations for journeys.

Indeed, the invention assists in enabling the movement of traffic to attain a natural flow. It assists in avoiding a restriction of this flow due, for example, to forcing traffic to stop at traffic lights or stop signs, and forcing all vehicles into a particular lane, typically a left lane, to allow the vehicles to turn left or right from the road on which they are travelling into a cross road. The natural traffic flow in question may itself reduce the need for particularly restrictive speed limits. It the invention makes higher speed limits more feasible, then this may further assist in contributing to reducing traffic congestion, and decreasing travel durations for journeys.

As illustrated by the different intersection embodiments described above, the invention, in preferred embodiments, is versatile in being adaptable to use with intersections have a variety of different numbers of connecting roads, and road configurations.

Claims

1. A traffic control intersection comprising: a first road having a plurality of substantially parallel first road lanes for directing road vehicles in a first direction along the first road; a second road running crosswise relative to the first road, the second road having a plurality of substantially parallel second road lanes for directing road vehicles in a second direction along the second road, the second direction extending at least partially leftward relative to the first direction, the second road further having a plurality of third road lanes being substantially parallel to one another and to the second road lanes along the second road, for directing road vehicles in a third direction along the second road, the third direction being opposite to the second direction in relation to the second road and extending at least partially rightward relative to the first direction; a first pathway interconnecting a lane, being the leftmost one of said first lanes in relation to said first direction at a position at which the first pathway connects to the first road, with a lane, being the leftmost one of said second lanes in relation to said second direction at a position at which the first pathway connects to the second road; and a second pathway interconnecting a lane, being the rightmost one of said first lanes in relation to said first direction at a position at which the second pathway connects to the first road, with a lane, being the rightmost one of said third lanes in relation to said third direction at a position at which the second pathway connects to the second road, the second pathway crossing at least one of said second lanes and being at a different elevation to the at least one second lane where it crosses it, to enable road vehicles to travel from said rightmost first lane to said rightmost third lane without travelling on the at least one second lane.

2. A traffic control intersection as claimed in claim 1 , wherein the first road defines a plurality of fourth road lanes, which are substantially parallel to one another and to the first road lanes, for directing road vehicles in a fourth direction along the first road, the fourth direction being opposite to the first direction relative to said first road.

3. A traffic control intersection as claimed in claim 2, further comprising a third pathway interconnecting a lane, being the leftmost one of said second lanes in relation to said second direction at a position at which the third pathway connects to the second road, to a lane, being a leftmost one of said fourth lanes in relation to the fourth direction at a position at which the third pathway connects to the first road.

4. A traffic control intersection as claimed in claim 2 or claim 3, further comprising a fourth pathway interconnecting a lane, being the rightmost one of said third lanes in relation to said third direction at a position at which the fourth pathway connects to the second road, to a lane, being the rightmost one of said fourth lanes in relation to the fourth direction at a position at which the fourth pathway connects to the first road, the fourth pathway crossing at least one of said second lanes and being at a different elevation to the at least one second lane where it crosses it, to enable road vehicles to travel from said rightmost third lane to said rightmost fourth lane without travelling on the at least one second lane.

5. A traffic control intersection as claimed in any one of claims 1 to 4, further comprising a third road running crosswise relative to the second road, the third road defining a plurality of substantially parallel fifth road lanes for directing road vehicles in a fifth direction along the fifth road.

6. A traffic control intersection as claimed in claim 5 wherein the third road defines a plurality of sixth road lanes, which are substantially parallel to one another and to the fifth road lanes, for directing road vehicles in a sixth direction along the third road, the sixth direction being opposite to the fifth direction in relation to said third road.

7. A traffic control intersection as claimed in claims 6, comprising a plurality of said first roads and a plurality of said third roads.

8. A traffic control intersection as claimed in claims 6, comprising three said first roads and three said third roads.

9. A traffic control intersection as claimed in claim 7 or claim 8 wherein, for each particular first road having, in relation to its first direction, another first road on its left hand side, the intersection further comprises a pathway interconnecting a lane, being the leftmost one of the first lanes of said particular first road in relation to the first direction pertaining to that first road at a position at which that pathway connects to that first road, with a lane, being the leftmost one of the fourth lanes of said other first road in relation to said fourth direction pertaining to said other first road at a position at which that pathway connects to said other first road.

10. A traffic control intersection as claimed in any one of claims 7 to 9 wherein, for each particular first road having, in relation to its first direction, another first road on its right hand side, the intersection further comprises a pathway interconnecting a lane, being the rightmost one of the first lanes of said particular first road in relation to the first direction pertaining to that first road at a position at which that pathway connects to that first road, with a lane, being the rightmost one of the fourth lanes of said other first road in relation to said fourth direction pertaining to that other first road at a position at which that pathway connects to said other first road.

11. A traffic control intersection as claimed in any one of claims 7 to 10 wherein, for each particular third road having, in relation to its sixth direction, another third road on its left hand side, the intersection further comprises a pathway interconnecting a lane, being the leftmost one of the sixth lanes of said particular third road in relation to the sixth direction pertaining to that third road at a position at which that pathway connects to that third road, with a lane, being the leftmost one of the fifth lanes of said other third road in relation to said fifth direction pertaining to said other third road at a position at which that pathway connects to said other third road.

12. A traffic control intersection as claimed in any one of claims 7 to 11 wherein, for each particular third road having, in relation to its sixth direction, another third road on its right hand side, the intersection further comprises a pathway interconnecting a lane, being the rightmost one of the sixth lanes of said particular third road in relation to the sixth direction pertaining to that third road at a position at which that pathway connects to that third road, with a lane, being the rightmost one of the fifth lanes of said other third road in relation to said fifth direction pertaining to that other third road at a position at which that pathway connects to said other third road.

13. A traffic control intersection as claimed in claim 6 wherein the third road is a continuation of the first road, with the fifth lanes being continuations of the first lanes, the sixth lanes being continuations of the fourth lanes, the first direction being the fifth direction and the fourth direction being the sixth direction.

14. A traffic control intersection as claimed in claim 6 or claim 13, further comprising a fifth pathway interconnecting a lane, being the leftmost one of said third lanes in relation to said third direction at a position at which the fifth pathway connects to the second road, to a lane, being the leftmost one of said fifth lanes in relation to said fifth direction at a position at which the fifth pathway connects to the third road.

15. A traffic control intersection as claimed in any one of claims 6, 13 and 14, further comprising a sixth pathway interconnecting a lane, being the rightmost one of said second lanes in relation to said second direction at a position at which the sixth pathway connects to the second road, to a lane being the rightmost one of said fifth lanes in relation to the fifth direction at a position at which the sixth pathway connects to the third road, the sixth pathway crossing at least one of said third lanes and being at a different elevation to the at least one third lane where it crosses it, to enable road vehicles to travel from said rightmost second lane to said rightmost fifth lane without travelling on the at least one third lane.

16. A traffic control intersection as claimed in claim 6 or any one of claims 13 to 15, further comprising a seventh pathway interconnecting a lane, being the leftmost one of said sixth lanes in relation to said sixth direction at a position at which the seventh pathway connects to the third road, to a lane, being the leftmost one of said third lanes in relation to the third direction at a position at which the seventh pathway connects to the second road.

17. A traffic control intersection as claimed in claim 6 or any one of claims 13 to 16, further comprising an eighth pathway interconnecting a lane, being the rightmost one of said sixth lanes in relation to said sixth direction at a position at which the eighth pathway connects to the third road, to a lane, being the rightmost one of said second lanes in relation to the second direction at a position at which the eighth pathway connects to the second road, the eighth pathway crossing at least one of said third lanes and being at a different elevation to the at least one third lane where it crosses it, to enable road vehicles to travel from said rightmost sixth lane to said rightmost second lane without travelling on the at least one third lane.

18. A traffic control intersection as claimed in any one of claims 1 to 17, comprising a traffic roundabout, the roundabout constituting at least two of said pathways.

19. A traffic control intersection as claimed in claim 18, comprising a central zone circumscribed by the roundabout and a chamber within the central zone, beneath the roundabout.

20. A traffic control intersection as claimed in claim 19 wherein the chamber includes a water storage tank.

21. A traffic control intersection as claimed in any one of claims 1 to 20, wherein at least one of the roads interconnected by the roundabout has at least one lane which passes over the roundabout whereby a utility space is at least partly defined by and between the roundabout and the road passing over the roundabout.

22. A traffic control intersection as claimed in claim 21 , further comprising, in the utility space, a building for accommodating occupants.

23. A traffic control intersection arrangement comprising: a traffic control intersection as claimed in any one of claims 1 to 22; and a pedestrian walkway structure for spanning the intersection, the walkway structure having a walkway spaced above, and extending across, the intersection, first access means extending between a first position adjacent the intersection and the walkway, for enabling pedestrians to move from the first position to the walkway, and second access means extending between the walkway and a second position adjacent the intersection, for enabling pedestrians to move from the walkway to said second position, wherein the walkway includes an inner section disposed above the intersection and an outer section, the inner section being selectively detachable from the outer section and adapted to be raised relative to the outer section.

24. An arrangement as claimed in claim 23 wherein each access means includes at least one of a stairway, an escalator, a ramp, and a lift.

25. A pedestrian walkway structure for spanning a roadway, the walkway structure comprising: a walkway spaced above, and extending across, the roadway; first access means extending between a first position adjacent the roadway and the walkway, for enabling pedestrians to move from the first position to the walkway; and second access means extending between the walkway and a second position adjacent the roadway, for enabling pedestrians to move from the walkway to said second position; wherein the walkway includes an inner section disposed above the roadway and an outer section, the inner section being selectively detachable from the outer section and adapted to be raised relative to the outer section.

26. A structure as claimed in claim 25 wherein each access means includes at least one of a stairway, an escalator, a ramp, and a lift.