Field of the Invention

The present invention relates, inter alia , to a pre-fabricated modular system for the installation of both a vehicle restraint system and at least one item of street furniture; and a pre-fabricated extension module for use in the system; and to a method of installing both a vehicle restraint system and at least one item of street furniture.

Background of the Invention

It has been known for many decades to install crash barriers (now known as “vehicle restraint systems”) along the outer edge of motorway carriageways and along the central reservation. Such vehicle restraint systems are also used on many non motorway routes.

Methods and systems for installing a vehicle restraint system (“VRS”) should be distinguished from methods and systems for installing bollards, as the requirements and features of the two are very different. With a VRS, the horizontal barrier (a substantially continuous metal rail or wire) is mounted on or attached to uprights - the spacing between the uprights is too great to be sure that they will prevent a typical vehicle (such as an average size saloon car) passing between them. Thus the presence of the horizontal barrier is essential to the efficacy of the system. In contrast, bollard systems comprise discrete individual bollards mounted close together with an interval or spacing between them which is too small to permit the passage of a typical vehicle. Thus, with bollard systems, typically just one or at most two will be impacted by the collision of a single vehicle and thus the bollards themselves must be robustly constructed, and firmly anchored, to resist the forces of an impact. With a vehicle restraint system, the horizontal barrier itself serves to dissipate the force of an impact to a large extent, and typically to spread the force of the impact among two or more uprights. As a result the upright support posts can be much less robustly constructed than bollards. In addition, bollards are typically used in comparatively small installations (perhaps up to a few tens of metres) whilst vehicle restraint systems may run for tens of kilometres - thus the cost considerations in each instance are very different. There are many different vehicle restraint systems in use, which differ to some extent in design and dimensions, but they are all generally similar and intended to prevent vehicles from crossing from one carriageway to the other, or to prevent vehicles from colliding with, or entering, roadside hazards.

A vehicle restraint system typically comprises a horizontal steel member, attached to a plurality of vertical steel support posts which are positioned at intervals. Each support post must be stably anchored, in order to resist impact in the event of a vehicle crashing into the crash barrier.

Currently there are three ways most commonly used in the UK to anchor vehicle restraint system support posts. These are: (i) “driven post”; (ii) “excavated foundation”; and (iii) “surface-mounted post”.

In the ‘driven post’ technique, the support post is simply driven into the ground, typically to a depth of 1 to 1.5 metres. This technique is cheap and easy and probably that which is most often employed. However, it requires that the ground is soft enough to drive in the post but hard enough to provide adequate support, and that there are no services (e.g. electric cables, drains, sewers, gas or water pipes) or other obstacles buried beneath the relevant location. If the driven post technique is not suitable, one of the other methods must be used. In particular, these do not require penetration into the ground to such a great depth. In the “excavated foundation” technique, a hole (of variable size) is dug, and the support post embedded in a concrete foundation formed in the excavated hole (with or without a metal socket therein to accommodate the post). The excavated hole is usually at least 600 mm deep and typically 800-1000 mm deep to accommodate a support post and anchor it adequately. In other circumstances it may be necessary to use a surface-mounted post. Typically, in this method, the support post is welded to a steel cradle, which in turn is bolted to holes in a concrete surface, the holes being filled with a synthetic resin which cures to firmly anchor the cradle and attached post to the surface. Whatever technique is used to anchor the support post, the ‘strength’ of anchoring must pass the associated “push test” - there are principally two tests, using a force of either 6 kiloNewtons or 9 kiloNewtons applied to the post (laterally, in the same direction that a vehicle would impact the post). The amount of ‘give’ in the post must be less than a particular threshold.

The various methods of anchoring posts all suffer from a variety of disadvantages. One very significant disadvantage is a lack of certainty regarding the suitability of a particular post-anchoring technique for a particular location, which makes planning very difficult. In particular because the characteristics of the ground, in which the posts are to be anchored, cannot be predicted in advance, and will tend to vary along the length of a road construction project, it is not possible to predict what type of anchor, (and, for example, what size of excavation) will be required to meet the push test criteria, without a needless over-specification of the anchor, which of course adds unnecessarily to the cost of the project.

Another disadvantage may often be a lack of “serviceability”. If a post is damaged in a collision, it can often be quite difficult to replace it, and repairs are thus quite complex.

A further problem is that the speed of installation of the posts (especially if using a technique other than the “driven post”) can be rather slow.

GB 2000852.0 (unpublished at date of filing of the present application) discloses a modular, pre-fabricated concrete foundation for installing a vehicle restraint system, which is aimed at overcoming or ameliorating some of the aforementioned problems. The present invention concerns, inter alia, improvements to and/or modifications of, the modular foundation described in GB 2000852.0. A copy of GB 2000852.0 is attached hereto as an annex.

Summary of the Invention In a first aspect, the invention provides a pre-fabricated modular system for installation of both a vehicle restraint system and at least one item of street furniture; the system comprising at least one pre-fabricated foundation module comprising a plurality of attachment points for securely attaching a vehicle restraint system to the foundation module; and at least one pre-fabricated extension module, which comprises one or more attachment points for securely attaching at least one item of street furniture to the extension module; and wherein the extension module is adapted and configured to engage with the foundation module.

In a second aspect the invention provides a pre-fabricated extension module, comprising one or more attachment points for securely attaching at least one item of street furniture to the extension module, the extension module being adapted and configured to engage with a pre- fabricated foundation for a vehicle restraint system.

The pre-fabricated foundation module is preferably of the sort disclosed in GB 2582430, but this is not essential.

The precise nature of the engagement between the foundation module and the extension module is not critical to the invention. However, it is important that the engagement is of sufficient extent and dimension such that the extension module benefits from the inertia and rigidity of the foundation module. In this way, the effective inertia and rigidity of the extension module is increased and, as a result, the mass and dimensions of the extension module can be reduced compared to those which would be required if the extension module were a “stand alone” footing for the item of street furniture. Generally speaking, the extension module will thus be less massive than the foundation module.

In some embodiments, the foundation module will be installed first, and the extension module will be installed overlying the foundation module. In other embodiments, this arrangement will be reversed and the foundation module will overlie the extension module. In yet other embodiments, the extension module may be installed at one end of a foundation module, or between the ends of adjacent foundation modules. Desirably, the foundation module and the extension module will comprise cooperating surfaces, such that the respective modules can be positioned on, beneath, around or abutting one another in frictional engagement.

As one example, the foundation module may be formed with a plurality of apertures and the extension module may be formed with a raised portion of suitable shape and dimension such that the raised portion is partially or wholly received within an aperture in an overlying foundation module; or, conversely, the extension module may be formed with a downwardly projecting portion such that, when the extension module is installed overlying a foundation module, the downwardly projecting portion of the extension module is partially or wholly received within an aperture in the underlying foundation module. Additionally or alternatively, the foundation and extension modules may be provided with respective cooperating grooves and ridges which engage one another when the modules are installed.

In a third aspect, the invention provides a prefabricated foundation module for use in installation of both a vehicle restraint system and at least one item of street furniture, the module comprising a plurality of attachment points for securely attaching a vehicle restraint system to the foundation module, and one or more attachment points for securely attaching at least one item of street furniture to the foundation module.

In the module of the third aspect, the plurality of attachment points for securely attaching a vehicle restraint system will conveniently be aligned, typically at or near the centre line of the module. The street furniture attachment point or points will desirably be set to one side of the aligned vehicle restraint system attachment points so that, in use, the item or items of street furniture will be behind the vehicle restraint system relative to a vehicle passing along the carriageway so that, in general, a vehicle cannot impact the street furniture without first colliding with the vehicle restraint system, which collision will absorb some of the kinetic energy of the vehicle.

The item of street furniture to be attached to the foundation module, or extension module, as the case may be, will most commonly be a lighting column for a street light, but any item of street furniture can be attached. Examples include direction signs, road signs, warning signs, traffic cameras, traffic lights and signals, emergency telephones, supports for overhead gantries, safety fencing, acoustic damping fencing, and so on.

The foundation module, or extension module, as the case may be, may comprise a plurality of street furniture attachment points. These may be identical, so as to provide a plurality of alternative positions for a single item of street furniture. Alternatively, the arrangement can provide for attachment of multiple units of an identical item of street furniture. Yet a further possibility is the incorporation in the foundation module, or extension module, as the case may be, of multiple attachment points of different types, to permit the attachment of different types of street furniture to the module. For example, a single foundation or extension module may permit the attachment of both a lighting column and a fence. A convenient type of attachment point for use on the foundation module or extension module, as the case may be, is a NAL socket, which is widely used for the attachment and mounting of street furniture items.

Yet more flexibility can be present in the system. For example, each foundation module may have only one site which can be occupied by a single extension module so as to engage with the foundation module. Alternatively, each foundation module could be provided with a plurality of sites, each of which could be occupied by a extension module. This allows a single extension module to be located at one of several different sites on the foundation module, offering a degree of choice where the extension module, and hence the item of street furniture to be attached to the extension module, is positioned. Alternatively, two or more extension modules could occupy respective engagement sites on a single foundation module thus permitting, for example, the attachment of one item to two different, spatially separated, extension modules (which may be desirable for greater strength and rigidity), or the attachment of two or more items of street furniture (which may be the same or different to one another) within the length of verge or central reservation taken up by a single foundation module.

Desirably the foundation module consists, or is predominantly formed of, concrete. The concrete may preferably comprise metal reinforcement. Preferred metal (e.g. steel) reinforcement will comprise a plurality of metal rods running along the long axis of the foundation module. If desired, one or more further transverse metal reinforcement rods may be provided, substantially at a right angle to the long axis of the foundation module.

In typical embodiments the foundation module will comprise a substantially rectilinear shape, similar to a concrete beam. Each modular section of foundation module will normally be essentially identical and, in practice, a plurality of such modules will be laid end to end to achieve the desired length of run of foundation module. The precise dimensions of the foundation modules are not critical, but a typical embodiment of the invention may be 6 to 8 metres in length, about 800 to 1200 mm wide and 200 to 400 m in height.

The foundation module will, in use, generally be located in a shallow trench. The depth of the trench will advantageously be less than the depth reached by the bottom of a support post driven into the ground in the “driven post” technique, and will be less than the depth of excavation normally required for the “excavated foundation” technique. Conveniently the trench will be 150-250mm deep, preferably about 200mm deep. In this way, a benefit of the invention is that such a relatively shallow trench is less likely to impact on buried services, and the person skilled in the art will have more freedom in deciding where to position the vehicle restraint system. The strength and inertia of the foundation module is such that a relatively shallow trench is sufficient to provide adequate anchorage. Indeed, in extremis (and typically only for temporary installations) it may be possible for the foundation module to be used above ground, without any trench.

It is highly preferred that the foundation module is perforated or aperture, as explained below.

There is a considerable variety of commercially available vehicle restraint systems, and these will typically dictate the interval between attachment points on the foundation module. For example, one system in widespread use has support posts located 1600 or 3200 mm apart, depending on the rigidity required in the system, whilst another commonly-used system has support posts at intervals of 2000mm; and the interval between attachment points on the foundation module of the invention may preferably correspond to one of these commonly-used distances, but other embodiments with different intervals, for use with other vehicle restraint systems, are perfectly feasible and envisaged in the present invention.

In one embodiment, the foundation module resembles a ladder, with transverse portions or “rungs” at regular fixed intervals across the foundation module where the attachment points are provided. The foundation module between the rungs is apertured or perforated, typically with one aperture or perforation between each pair of adjacent “rungs”. The apertures or perforations are conveniently positioned along the centre line of the foundation module. Advantageously the apertures or perforations extend over more than half of the separation between adjacent attachment points.

One purpose of the apertures or perforations in the foundation module is to facilitate access to any services which might be locatable or located beneath the foundation module, thereby fairly readily permitting inspection, maintenance or repair of the services as required. Another purpose of the apertures or perforations is to facilitate drainage of rain water and the like. In order to facilitate access to underlying services, it is highly preferred that any metal reinforcing components present in the foundation module do not extend into the apertures or perforations. For this reason, the use of reinforcing mesh or grids is preferably avoided, and instead reinforcing bars or rods, which can be offset beyond the side of the apertured portions of the foundation module, are advantageous.

However, it may be preferable that some or all of the apertures are provided with a mesh, typically made of steel, which is removably located within the apertures. Such mesh is to be distinguished from the structural reinforcing elements which are embedded within the concrete of the foundation module and cannot be removed therefrom. The purpose of the removable mesh is to permit the passage of rainwater or other fluids through the apertures, whilst preventing the ingress of soil, leaves or the like. Water or other fluid passing through the apertures may enter a drainage channel provided in an optional conduit unit described below. The removable mesh may be secured within the apertures by releasable attachment means, such as screws, clips or the like. The mesh may be removed to facilitate access to services located beneath the foundation module.

The exact type of attachment point provided on the foundation module is not critical to the present invention, and several different designs of attachment point can be envisaged. (Equally, the type of attachment points provided on the extension modules is not critical to performance of the invention.) Generally, however, each attachment point on the foundation module facilitates the secure anchoring of a (substantially vertical) support post for a VRS barrier. The attachment points on the foundation module are desirably predetermined, and conveniently are at a fixed, and preferably regular, interval along the foundation module. It is a highly preferred feature of the invention that the support post, once attached to the foundation module, is sufficiently firmly anchored that it will be guaranteed to meet the 6 kiloNewton or 9 kiloNewton push test, as appropriate. The inventor had found that, in tests, the support post will typically deform rather than the foundation module moving.

In this way, using the pre-fabricated foundation module of the invention, a planner planning the construction of a road can know in advance, with certainty, that the specified support posts for a vehicle restraint system will, when in position, pass the appropriate anchor push test. Further, it avoids any need to test the conditions of the ground along the edge of the carriageway to ascertain what type of post anchor would be suitable.

In order to provide the necessary anchoring capability for the support posts, the foundation module of the invention can readily be designed with sufficient rigidity and mass/inertia. The requirements for these parameters will depend on the manner in which the pre-fabricated foundation module is to be used, and the location of its deployment. It is envisaged therefore that, in practice, a range of pre-fabricated foundation modules may be produced with different dimensions and mass, such that a skilled person planning a road construction can select those pre-fabricated foundation modules which are most appropriate for the particular construction. Thus, for example, bigger and more massive pre-fabricated foundation modules may be appropriate if the foundation modules are to be surface-exposed and/or used on ground of relatively low resistance; whilst smaller and less massive pre-fabricated foundation modules may be appropriate for situations in which the foundation module will be sited within a trench which is back-filled to a significant extent.

Other advantages stemming from the invention may include:

(a) increased speed of installation - the foundation modules can be rapidly installed, there is no need to conduct ground testing, and generally less need to perform any excavation by hand (which slows down the rate of construction);

(b) increased flexibility - as the foundation module does not need to be positioned as deep as driven posts, there is less risk of damage to underlying services during installation of the vehicle restraint system, and less likelihood of underground obstructions interfering with the preferred siting of the support posts;

(c) increased reliability - the support post positions are predetermined by the attachment points on the foundation module, leaving less chance of error by workmen on site;

(d) reusability - the foundation module can be easily dug up and re-used e.g. if utilised on a temporary construction site or if a carriageway is re-routed, and especially in view of the modular nature of the foundation module, one or more sections of foundation module can be easily replaced (e.g. if damaged);

(e) increased ease of access to services located beneath the vehicle restraint system, due to the perforated or aperture nature of the preferred foundation module;

(f) reduced verge requirement - currently, due to health and safety considerations, it is standard practice in the industry to avoid installing driven posts, or machine- excavated foundations, within 1000 mm of underground services - as a result, a great width of verge is required to install both services and vehicle restraint systems whilst allowing for the 1000 mm separation between the two. In contrast, the present system potentially allows for the vehicle restraint system to overlie any services with far less risk than conventional installation techniques, such that a narrower verge can be used; and

(g) increased compliance with Highway Construction Details (“HCD”) - there is, in principle, a requirement that any concrete used in the installation of the vehicle restraint system should be allowed to cure for 28 days before the road is opened to traffic. In practice this is frequently disregarded, but the use of a pre-fabricated concrete foundation module allows the regulation to be observed.

In one embodiment, each attachment point on the foundation module comprises a socket formed in, and optionally through, the foundation module, such that a support post may be passed into, and preferably through, the foundation module. The support post will typically extend about 300 to 500 mm below the foundation module, preferably 250 to 350 mm. If desired, the socket may be provided with a sleeve or liner, which may optionally be removable from the foundation module. The sleeve or liner is conveniently formed of metal such as steel.

In one embodiment, the sleeve or liner is dimensioned so as to be received snugly within the socket formed in the foundation module, but may extend beneath the foundation module by a length (e.g. 100-500 mm) suitable to accommodate a bottom part of a support post. The sleeve or liner may project above the foundation module by an amount e.g. in the range 0-50 mm. The sleeve or liner, if formed as a separate component, removable from the foundation module, may possess a small flange portion or collar, extending around the upper surface about the socket, so as to help retain the sleeve or liner in a desired positon relative to the foundation module.

In some embodiments the sleeve or liner may desirably be formed with a pointed, conical, or generally tapered or wedge-shaped lower end, to facilitate insertion into the ground beneath the foundation module.

The sockets formed in the foundation module may, in preferred embodiments, take the form of generally cylindrical apertures through the foundation module which, in cross-section, may typically be circular or, more desirably square or rectangular in section. The most convenient shape is a rectangular section cylinder, which conforms to the shape and dimensions of commonly-used support posts (e.g. a ‘Z’ -section support post, although other commonly used support posts are formed with an Ή’ or T -shaped section; any of these can be accommodated by suitably shaped and dimensioned sockets in the foundation module).

In other embodiments, the foundation module may comprise a plurality of sockets, with or without metal sleeves or liners, and the support posts do not necessarily extend beneath the foundation module.

In such embodiments, the foundation module may conveniently be of increased dimension in depth around the sockets, compared to the majority of the foundation module, so as to enhance the rigidity of the foundation module around the sockets, the better to resist any force imposed as a result of a vehicle colliding with the vehicle restraint system. In addition, it may be advantageous to provide each socket with at least one drain hole, so that rain or other water cannot accumulate in the socket and facilitate corrosion or other degradation of a fence post within the socket.

In some embodiments, one or more sockets in the foundation module may be provided with retaining means for retaining a support post within the socket. The retaining means is preferably readily releasable so that a support post retained in the socket can be readily removed if desired. In this way, if a support post is damaged (e.g. as a result of a vehicle colliding with the post or barrier), it may readily be replaced with a new support post. In one embodiment, the plurality of sockets in the foundation module are each formed with a pair of bores in the walls thereof, one on each side of the socket, which are aligned. In use a retaining bolt or pin (e.g. made of steel) is inserted into one of the bores in the socket wall, and then passed through a corresponding pre-formed hole towards or near the base of the support post when the post is inserted into the socket, and thence into the other aligned bore in the opposite socket wall. For ease of removal of the retaining bolt or pin, it is preferable that the bores extend at least on one side, and desirably on both sides, right through the attachment point to an adjacent aperture. The retaining bolt is preferably releasably secured within the socket by a nut or the like.

In another embodiment, each attachment point on the foundation module substantially corresponds to a conventional mounting position for a surface-mounted post.

A conventional surface-mounted post is typically formed with an H-shaped base plate, the two arms of the Ή’ being flattened flange portions with a hole disposed towards each end, such that there are four holes in total in the base plate. Four corresponding holes are drilled in the road surface, foundation or other solid surface on which the surface-mounted post is to be positioned, and a metal anchor or fixing is placed in each of the holes in the solid surface and fixed therein by the curing of a synthetic resin. The base plate of the post is then attached to these anchors or fixings by positioning metal studs or fasteners, such that each stud or fastener passes through one of the holes in the base plate and enters into a strong, screw-threaded engagement with a respective one of the metal anchors or fixings in the solid surface.

Accordingly, in embodiments of the invention adapted and configured for use with surface-mounted posts, it may be desired for each attachment point to be provided with at least one (preferably a plurality) of pre-drilled or otherwise pre-formed holes, to indicate the desired position of metal anchors or fixings to be inserted to anchor the support post to the foundation module. It is possible however, that at least some, or even all, of the holes in the attachment point are not pre-formed but are introduced in situ, typically by drilling. The post will then be attached to the foundation module in substantially conventional manner by metal studs, fasteners, nuts or other securing means which enter into a screw-threaded engagement with the anchors or fixings already secured in the foundation module.

Indeed, in a preferred embodiment of the invention for use with surface-mounted type posts, the (typically metal) anchors or fixings may be already present in the foundation module as supplied to the construction site. In particular, it may be preferred to incorporate the anchors or fixings at the concrete-casting stage of the foundation module (i.e. substantially at the outset), which eliminates the need to drill holes into the foundation module, after the concrete has set, to accommodate the anchors or fixings.

It will be appreciated that, whilst it is possible that two or more different types of VRS attachment point may be present on a single foundation module, it will generally be advantageous that a single type of VRS attachment point is present on a single foundation module.

It is a preferred feature of the invention that opposed ends of the foundation module are shaped so as to co-operate with the opposed ends of other foundation modules in accordance with the invention. In one embodiment, one end of a foundation module is shaped to form a male member, and the opposed end of the foundation module is reciprocally shaped to form a female member, such that the male member of a first foundation module may co-operate with the female member of a second foundation module. A convenient selection of male and female members comprises a male member in the shape of a projecting trapezium or an inverted triangle with the apex truncated, and the female member being formed as a reciprocally shaped re-entrant trapezium or the re-entrant base of a truncated triangle. More especially, the opposed ends are desirably shaped and dimensioned so as to permit a first foundation module to be moved in a substantially vertical plane relative to a second foundation module, but so as to resist lateral (and/or rotational) relative movement in at least one direction in a substantially horizontal plane. In this way, a second foundation module can be lowered into place, adjacent to, and in co-operating engagement with, a previously positioned first foundation module.

Thus, for example, conveniently, once the abutting ends of adjacent foundation modules have been placed in engagement, the foundation modules may be separated by lifting one or other of the foundation modules in a substantially vertical plane, but the foundation modules cannot be separated by relative horizontal movement in a transverse direction at right angles to the long axis of the foundation module. Where the first and second foundation modules engage with an interlocking (e.g. dovetail) engagement, the foundation modules will resist relative movement in any direction in a horizontal plane. In other simpler embodiments, relative movement in a horizontal plane generally along the long axis of the foundation modules may still be permitted, but transverse movement generally at right angles to be the long axis of the foundation modules is resisted. Such an embodiment thus permits a first foundation module to be connected to a second foundation module by relative horizontal movement thereof along the long axis of the aligned foundation modules, or by relative vertical movement of the two aligned foundation modules.

In yet another embodiment, the ends of adjacent foundation modules are adapted and configured so as to allow for at least some relative rotational or pivotal movement in a horizontal plane. As an example of such an embodiment, the foundation module may be formed with a projecting male member at one end and a reciprocally shaped female recess at the other end, wherein the male member has a curved face, which may preferably describe a substantial part of a circle. Where the male member is semicircular or describes less than half of a circular arc, and the female recess is reciprocally shaped and is a semi-circular recess or describes less than half of a circular arc, then the opposed male and female ends of adjacent foundation modules can be engaged and disengaged by simple relative longitudinal movement, pushing the two foundation modules together to engage, or pulling them apart to disengage.

However, if desired, the foundation modules may be formed with a projecting male member which describes an arc of more than 180° of a circle (e.g. 220-270°), and the reciprocal female recess similarly describes an arc of greater than 180°. In such an embodiment, there is an interlocking engagement between the male member and female recess, such that the opposed ends of adjacent foundation modules cannot be engaged or disengaged by simple relative longitudinal movement in a horizontal plane, but can be engaged or disengaged by relative vertical displacement.

In such embodiments as described in the preceding paragraphs, one or both ends of the foundation module are preferably formed with an angled shoulder portion, which permits a greater angle of relative rotational or pivotal movement between adjacent, engaged foundation modules. It will be apparent that, in embodiments of the invention which allow for some limited relative rotational or pivotal movement of adjacent foundation modules, adjacent foundation modules can be engaged with one another (e.g. by relative vertical displacement, sliding or dropping one foundation module into engagement with its neighbour), and rotated through a desired angle to impart a desired change of direction or ‘kink’ in a run of foundation modules.

It will also be apparent to those skilled in the art that, in embodiments of the invention in which an extension module is adapted and configured to be positioned between, and engage with, the end portions of respective foundation modules, the various shapes and geometries described above in relation to foundation modules can be adopted in, or mirrored by, corresponding or co-operating surfaces of the extension module, as necessary, to allow the extension module to engage with the foundation module.

In addition, or as an alternative, to the aforementioned shaped co-operating ends of adjacent foundation modules, in some embodiments the foundation module may be provided with connecting means, which functions to connect the opposed ends of adjacent foundation modules. For example, in one embodiment, one or more bores (preferably two) are provided at each end of a foundation module), which bores are preferably sufficiently long to communicate with the aperture nearest the end of the foundation module. In this way a metal bolt, tie or the like may be inserted into one end of a bore, and pass through into an aligned, co-operating bore formed in the end of the adjacent foundation module, and secured therein by a nut or other fastener. Typically an M24 (i.e. 24mm diameter) bolt and associated nut is suitable for this purpose. M24 bolts are readily available commercially in lengths up to about 240mm. Conveniently a pair of bores is formed at each end of the foundation module.

Notwithstanding the preceding paragraph, in preferred embodiments of the system and method of the invention, adjacent foundation modules are held in position without requiring the aid of metal fixings between them and without being set in concrete footings, which cures about them. Typically the foundation modules are held in place primarily by their own weight and by engagement of co-operating shaped ends of respective adjacent foundation modules. In like manner, additionally or alternatively, in preferred embodiments of the system and method of the invention, one or more extension modules are held in position on a foundation module without requiring the aid of metal fixings thereto and without being set in a concrete footing which cures about it. Typically the extension module is held in place by the weight of the foundation module and by engagement of co-operating shaped portions of the extension module(s) and foundation module which engage with one another.

In preferred embodiments, the ends of the foundation module are made, and/or the foundation modules positioned, in such a way as to allow for thermal expansion and contraction of the foundation module. For example, for a foundation module substantially consisting of concrete, an 8000mm long foundation module might be expected to extend or contract in length by up to 4mm.

Generally the ends of the foundation module will be perpendicular to the long axis of the foundation module. However it may be convenient for some foundation modules to have at least one end which is at an angle of e.g. between 5 and 40 degrees to the long axis of the foundation module, where the foundation module is to be installed along a curved section of carriageway. It will be apparent that, if desired, both opposed ends of the foundation module may be set at an angle to the long axis of other than 90°. This angle may be the same at both ends, or may be different. Equally, an extension module for use in the invention may be provided with opposed ends which may not be parallel to one another (e.g. at an angle of between 5 and 40°).

It may be desirable, in some embodiments, for the foundation module of the invention to be held in place by bracing means. This may be especially desirable where the ground is insufficiently stable to provide adequate support for the foundation module and/or where the foundation module is to be installed on a narrow verge at a roadside. The bracing means may, for example, comprise a stake or post, typically of metal (e.g. steel) which is driven into the ground. The bracing means might act on a front or rear edge of the foundation module. Additionally or alternatively the foundation module may be provided with one or more bracing holes (e.g. formed in the transverse portions and/or at the end regions of the foundation module), through which a bracing stake or post may be driven. The bracing means may advantageously be secured in place by concrete, or the bracing means may be provided with a welded plate, flange or collar which can be attached to the foundation module by a conventional “surface mounted” technique, of the sort already described elsewhere. In one embodiment, the foundation module is formed with one or more bracing holes of 120 x 50mm dimension, which accommodate a widely-used metal post acting as a bracing means.

As will be apparent, the system of the present invention further typically comprises an extension module adapted and configured to engage with the foundation module. The foundation module provides a footing for one or more items of street furniture. The item of street furniture may include, but is not limited to, one of the following: a street light, a road sign, and emergency telephone, a yardage counter, a light for a road sign.

The extension module will preferably be substantially formed of concrete, optionally reinforced concrete. The extension module will comprise a suitable attachment point or anchorage for the relevant item of street furniture. In a typical embodiment the extension module will comprise an NAL-socket, which is widely used as an anchor for various items of street furniture.

The system of the invention allows for the substantially simultaneous installation of both a vehicle restraint system and one or more items of street furniture, since the footings and attachment points for both the VRS and the street furniture can be positioned and installed in essentially a single operation. This greatly simplifies planning and implementation of highway construction projects. For example, a motorway verge or other highway boundary can be completely simulated or modelled on a computer in advance of construction, since all of the components required may be pre-fabricated with predetermined characteristics (size, strength etc.). In addition, the various components may be assembled or disassembled in situ and are reusable. Since the components can be installed “in one go” by a single contractor, the system of the invention avoids the need to coordinate multiple contractors during the construction project. In particular, the invention provides for the provision of attachment points for multiple independent systems on a single pre-cast concrete block. Another unique feature of the invention, in preferred embodiments, is as follows: conventionally, it is necessary to position a lighting column so as to be outside the "working width" of a vehicle restraint system i.e. the lighting column is beyond the maximum extent of deflection of the crash barrier (in the event of a vehicle impacting the barrier), such that the occupants of the vehicle cannot be harmed by the lighting column. With the present invention, a combined crash barrier/lighting column unit can be investigated in a test impact to demonstrate that a lighting column, possibly within the "working width" of the crash barrier, will not harm the occupants of an impacting vehicle. As a result of such tests, using standardised components, it will be possible to position lighting columns (or other items of street furniture) within the working width of a crash barrier, and thereby reduce the width of the verge or otherwise reduce the width required to install the street furniture.

In a fourth aspect, the invention provides a method of installing a vehicle restraint system and at least one item of street furniture, the method comprising the steps of:

(a) positioning a selected prefabricated foundation module, as previously defined above, at a desired location;

(b) attaching at least one VRS support post to an attachment point on the foundation module;

(c) providing at least one attachment point for attaching an item of street furniture, said street furniture attachment point being present either on the foundation module, or on an extension module, which extension module, if present, is positioned in engagement with the foundation module.

The method will generally further comprise the step (d) of attaching a VRS barrier to the support post. Preferably a plurality of support posts will be attached to the foundation module, and typically a plurality of foundation modules will be deployed, each having a plurality of support posts attached thereto. The method will also typically further comprise the step (e) of attaching an item of street furniture to the street furniture attachment point.

In those embodiments of the invention in which an extension module is utilised, the extension module will be positioned in engagement with one or more foundation modules. The sequence in which the various modules are positioned will depend on the characteristics of the embodiment employed. Thus, for example, foundation modules may be positioned initially, and one or more extension modules subsequently deployed on top of the foundation modules, or this sequence may be reversed. In those embodiments in which an extension module is deployed between neighbouring foundation modules, will normally be desirable for one of the foundation modules to be deployed first, followed by the extension module, and then the second foundation module. However, in principle, this sequence can be varied (for example, the two foundation modules could be deployed initially, followed by installation the extension module therebetween; or the extension module could be deployed initially, followed by the deployment of a respective foundation module on either side of the extension module). In any event, it is a feature of such embodiments that the extension module is adapted and configured so as to engage with at least one foundation module.

The method may also advantageously comprise an initial step of excavating a trench of length and width suitable to accommodate one or more of the selected prefabricated foundation modules. Desirably the trench is dug by machine. The depth of the trench may depend on several factors, including, for example: the depth below ground level of any underlying services (such as drains, sewers, electric cables or gas pipes); communication cables or hard ground. Typically the trench will be 150- 250mm in depth.

It will be appreciated that the method of the invention will normally involve positioning a plurality of foundation modules, most or all of which will be of substantially identical design and construction. Desirably the end of one foundation module will be shaped and dimensioned so as to engage with the opposed end of another foundation module, such that the step of positioning the foundation modules may involve placing adjacent foundation modules into engagement or even interlocking relationship with one another. Optionally, in addition, or as an alternative, to the aforementioned engagement, connecting means such as metal bolts or ties may be inserted into bores provided at the ends of adjacent foundation modules, and secured with nuts or other fasteners, the bores of adjacent foundation modules being aligned to receive the bolts.

If any preliminary excavation has been required, some or all of the spoil may be backfilled onto the foundation module once the support posts have been anchored to the foundation module. This back-filling may be performed before or after the vehicle restraint member/crash barrier has been attached to the support posts.

In some embodiments, the top of the foundation module when installed may be slightly below the level of the surface of the carriageway, such that surface water on the carriageway may be readily drained onto the foundation module and then pass through the apertures therein. In other embodiments, the top of the foundation module when installed may be substantially level with the surface of the carriageway. In still other embodiments, when installed the top of the foundation module may be above the surface of the carriageway, typically about 100- 125mm above the surface of the carriageway. This arrangement has the advantage that the foundation module may form a kerb or edging to the carriageway. However, the side wall of the foundation module may then tend to prevent drainage of surface water from the carriageway onto the verge and/or onto the foundation module. To avoid this, the side wall of the foundation module may be provided with one or more drainage gaps to allow water from the carriageway to drain into the foundation module.

In some embodiments, the foundation module may be mounted or positioned on an underlying conduit unit. The conduit unit may be a separate pre-fabricated component, or may form an integral sub-component of the foundation module. The conduit unit is conveniently formed of concrete. It is preferred that the conduit is separate from the foundation module, as this aids removal of the foundation module and the conduit unit in the event that access is required to the services etc. located beneath the conduit unit. The conduit unit may be provided in sections of the same length as the foundation module, or may be different (longer or shorter than the foundation module). In one particular embodiment, the conduit unit is provided in pre-fabricated lengths of 2 metres or so (e.g. substantially shorter than the foundation module) in order to facilitate removal of one or two selected individual conduit units if desired.

In a preferred embodiment the conduit unit has a cross-section resembling adjacent, conjoined, letters “n” and “u”, such that the conduit unit substantially possesses rotational symmetry of order 2 about its long axis.

The “n” shaped part of the conduit unit may form a protective arch over services, laid beneath the conduit unit. The services may comprise, for example, electrical cables, gas pipes and the like.

The “u” shaped part of the conduit unit may form a drainage channel to drain away surface water which falls onto the structure or which drains onto the structure from the surface of the carriageway.

In some embodiments the foundation module and the conduit unit are provided as separate components. In this event, it is desirable that positioning guide means is provided on one or both units to assist in placing the foundation module in a desired position relative to the conduit unit. An example of such positioning guide means is to have co-operating surfaces formed on the foundation module and conduit unit, which guide means are formed with a stepped profile, e.g. a profile on the upper edge of a conduit unit which co-operates with a reciprocally stepped profile on the bottom edges of the foundation module.

In other embodiments, the foundation module and conduit unit may form a single integrated component. For example, they may be cast ab initio as a single component in concrete, or they may be cast separately but assembled together after manufacture for delivery onsite as a single, pre-assembled component.

As noted above, an advantage of the foundation module of the invention is that it is reusable. Accordingly in some methods in accordance with the invention, there may be a preliminary step of obtaining the selected pre-fabricated foundation module by digging up and/or repositioning a previously deployed foundation module. For example, where a foundation module has been deployed to support a vehicle restraint at a temporary site, the foundation module may subsequently be reused at a second or further location.

The fabrication of the foundation module may be achieved by essentially conventional manufacturing techniques known in the industry, but with minor adaptations suitable for the invention. Thus, for example, a concrete foundation module in accordance with the invention may be made by pouring concrete into the mould cavity space of a metal mould of the desired size and shape. Desirably the wet concrete used is of grade ST5 or greater.

Prior to, during, or immediately after, the pouring of the concrete into the mould cavity, any desired metal reinforcing components will also be introduced into the mould cavity. In some embodiments (especially those intended for use with conventional surface-mounted posts), metal anchors or fixings will also be located, at desired positions, in the mould cavity. A jig is conveniently employed to ensure accurate positioning of the metal anchors or fixings, which latter will form an integral part of the foundation module once the concrete has set.

The invention will now be further described by way of illustrative example and with reference to the accompanying drawings, in which:

Figure 1 A is a plan view of one embodiment of the invention;

Figure IB is a side elevation of the embodiment shown in Figure 1A, with additional accessories;

Figures 1C and ID are illustrations of the layout of integral steel reinforcement bars within one embodiment of the invention, as seen from above (1C) or one side (ID); Figures 2 and 3 are perspective views of a system for installing a vehicle restraint system in accordance with the second aspect of the invention;

Figure 4 is a perspective view of a further embodiment of a system for installing a vehicle restraint system in accordance with the second aspect of the invention;

Figures 5A-5C are various views of another embodiment of a foundation module for use in a system in accordance with the present invention; Figures 6-8 are partial views of various embodiments of a system in accordance with an aspect of the invention; and

Figure 9 is a perspective view of a system in accordance with the invention, in situ, with an installed VRS and various items of street furniture.

Examples

Example 1 A first embodiment of a foundation module suitable for use in the first or second aspects of the invention is shown in plan view in Figure 1A. The apparatus comprises a pre-fabricated foundation module 2 of reinforced concrete. The module is about 8 m long, 1000 mm wide, and 200 mm deep. A first end of the module is formed with a projecting male member 4, whilst an opposed second end of the module 2 is formed with a re-entrant female member 6. The male member 4 and the female member 6 are reciprocally shaped, so that the male member 4 of a module 2 can be received within the female member 6 of another module 2 so as to create an interlocking engagement, which permits relative movement of the two modules in a substantially vertical plane, but resists relative lateral movement in a substantially horizontal plane.

The module comprises four attachment points 8-8’”, which are at a fixed interval of 2000 mm. Each of the attachment points 8-8’” comprises an identical socket through the entire depth of the module 2. As best seen in Figure IB, each socket is provided with a removable steel liner or sleeve, locatable within the socket and extending beneath the module 2 into the ground below. The socket is of rectangular cross- section, shaped and dimensioned to receive and retain the liner or sleeve, which is in turn shaped and dimensioned to receive the end of a commercially-available Z-section support post of common and conventional design.

Each attachment point 8-8”’ is provided in a respective ‘rung’ 10-10”’ across the module. Between adjacent rungs 10-10”’ is a large aperture 12-12” formed in the module. Additional smaller apertures 14,14’ are provided towards opposite ends of the module. The highly apertured nature of the module facilitates access to, and inspection, maintenance or repair of, any services underlying the module 2 when it is in situ along the edge of a road carriageway.

In order to use the apparatus, a trench of suitable dimensions is excavated at the desired location and the module is lowered into the trench. A steel sleeve or liner 16 (seen in Figure 1A) is placed in each of attachment points 8-8”’ and driven into the ground, and a support post is then inserted into each steel sleeve or liner 16. The dimensions of the sleeve or liner are such that a widely-used, commercially available support post may be snugly received within the sleeve or liner 16, so as to be firmly anchored by the sleeve and module. The mass and rigidity of the module 2 allows the support posts to be firmly anchored without driving the posts to the depth of penetration which would be required in the absence of the module.

Once the support posts have been secured to the module, the spoil excavated in the digging of the trench may be partially or wholly back-filled on top of the module 2, depending on the requirements of the constructor, and the vehicle restraint barrier or crash barrier is attached to the anchored support posts by wholly conventional means (e.g. nuts and bolts).

In the embodiment illustrated, the sleeve or liner 16 is shaped and dimensioned so as to snugly receive a conventional 170 x 49mm ‘Z’ section post. If desired, the foundation module 2 can also be provided with one or more attachment points for securely attaching at least one item of street furniture to the foundation module. This permits, if desired, the optional omission of an extension module from the system of invention.

Figures 1C and ID illustrate an embodiment generally similar to that illustrated in Figures 1A/1B (although shorter, and with fewer ‘rungs’ 10 and apertures 12), and like components are denoted with common reference numerals. The Figures illustrate the internal arrangement of the integral steel reinforcing bars provided in the foundation module. These comprise four parallel pairs of main bars 3 along the long axis of the module, which are joined by a plurality of transverse members, of which a representative example is denoted by reference numeral 5. The transverse members are situated within the ‘rungs’ 10. All the bars 3, 5 are of conventional H10 size. It is apparent from the Figures that the reinforcement bars do not protrude into the apertures 12.

Example 2

Referring to Figure 2, there is illustrated a step in the installation of a vehicle restraint system in accordance with the method of the invention. The method comprises installation of a foundation module 2, of the embodiment shown in Figures 1A & IB, together with a plurality of vertical support posts 20-20’”. Each support post 20-20”’ is a conventional Z-section steel post, which is received in a respective one of the corresponding attachment points 8-8”’ (shown in Figure 1 A) and the associated sleeve or liner 16 (shown in Figure IB).

A conventional horizontal steel crash barrier can then be attached to the support posts 20-20”’ by nuts and bolts, the support posts being apertured to permit the passage of suitably sized bolts.

A further example illustration of an installation method in accordance with the invention is shown in Figure 3. The illustrated example comprises a foundation module 2. At each of the plurality of attachment points on the module is a vertical support post 20-20”’. These are anchored to the foundation module 2 via their integral base plate, of the type used conventionally to anchor a surface-mounted post. The support posts 20-20”’ with welded base plate are anchored to the module 2 by two-part metal bolts sunk into holes drilled into the foundation module 2. A bottom part or anchor is positioned in the foundation module; and a top part is passed through a pre-formed hole in the base plate and into screw-threaded engagement with the bottom part or anchor. Conveniently the bottom part or anchors are incorporated into the module 2 at the casting stage, which avoids the need for subsequently drilling holes into the module, after it has set, to accommodate the anchors. Four two-part bolts are used, one at each comer of the base plate, and a liquid synthetic resin is used to fill the residual volume. The resin is allowed to cure, such that the base plates, and their attached support posts 20-20”’, are firmly anchored. A conventional ⁴ W’-section steel crash barrier 22, is then attached in a substantially horizontal plane to the substantially vertical support posts 20-20”’. Again, the attachment is by use of conventional fixings, such as nuts and bolts.

As described in relation to Example 1, the foundation module 2 illustrated in Figure 3 could be provided with one or more attachment points for securely attaching at least one item of street furniture to the foundation module.

It will be noted that the foundation module 2 in Figure 3 differs in certain details from the foundation module 2 shown in Figures 1 A/ IB & 2. One difference is the absence of sockets penetrating through the entire depth of the foundation module in Figure 3. In addition it can be seen that, because the system in Figure 3 requires the use of base plates, having a relatively wide base, to attach the vertical support posts 20 etc., the transverse members 10 are substantially wader than the corresponding transverse members of the module shown in Figures 1A/1B & 2.

Example 3

Figure 4 and illustrates a vehicle restraint system, installed using an embodiment of a system in accordance with the invention. The illustrated embodiment is generally similar to that shown in Figures 2 and 3, and common reference numerals are used to indicate like components. Figure 4 shows the system installed in situ along the outer edge of a carriageway 30. The foundation module 2 is mounted above a pre-fabricated services conduit unit 32. The conduit unit 32 has a cross-section resembling conjoined adjacent letters “n” and “u”, such that the conduit unit substantially possesses rotational symmetry of order 2 about its long axis. The conduit unit is conveniently formed of concrete.

The “n” shaped part 34 of the conduit unit 32 forms a protective arch over services 36, laid beneath the conduit unit. The services may comprise, for example, electrical cables, gas pipes and the like.

The “u” shaped part 38 of the conduit unit 32 forms a drainage channel to drain away surface water which falls onto the structure or which drains onto the structure from the surface of the carriageway 30, which is substantially flush with the top of the foundation module 2. In this way, the system can help reduce the build-up of standing water on the surface of the carriageway.

One or more of the apertures 12, 14 etc. in the foundation module are provided with a metal (e.g. steel) mesh which permits the passage of rain or other precipitation into the channel 38, whilst preventing the ingress of soil, leaves and the like which might otherwise partially or wholly block the channel 38.

The mesh is not embedded within the concrete of the module 2 but is instead readily removable from the module, being attached thereto by releasable attachment means, such as screws, clips or the like, or simply resting on a flange or ledge portion of the foundation module. The mesh has an array of square holes of about 10mm sides, and may be covered by an optional layer of drainage-permitting material such as 20mm flint filter stone or similar.

In the illustrated embodiment, the prefabricated foundation module 2 and the prefabricated conduit unit 32 are shown as separate components, the outer edges of the conduit unit 32 having a stepped profile which engages with a co-operating profile on the outer edges of the module 2. This engagement facilitates alignment of the foundation module 2 with the conduit unit 32 such that the foundation module can easily be placed in the desired position relative to the conduit unit.

In other embodiments, the module 2 and conduit unit 32 may form a single integrated component. For example, they may be cast ab initio as a single as a single component in concrete, or they may be case separately but assembled together after manufacture for delivery onsite as a single, pre-assembled component.

Example 4

Figures 5A-5C are various views of a further embodiment of a foundation module of use in a system/method in accordance with the invention.

Figure 5A is a perspective view of a pair of foundation modules which are in an interlocking engagement which allows for limited relative rotational or pivotal movement of the engaged adjacent foundation modules. Figures 5B and 5C are plan views of the engaged portions of the foundation modules, showing that the engagement allows for limited relative rotational or pivotal movement of the foundation modules in a horizontal plane.

Where the features shown in Figures 5A-5C are generally equivalent or correspond to features shown in other drawings they are indicated with common reference numerals.

Referring to Figures 5A-5C, two identical foundation modules 2, 2a have ends adapted and configured so as to allow for at least some relative rotational or pivotal movement in a horizontal plane. The foundation modules 2, 2a are each provided with a projecting male member 4 which has a curved face describing about 260-270° of a circular arc. The male member 4 of foundation module 2 is received within the reciprocally shaped female recess 6 formed on the end of foundation module 2a. The interlocking engagement created by the insertion of male member 4 into the female recess 6 prevents engagement and disengagement of the foundation modules 2, 2a by simple relative longitudinal movement. Instead, the foundation modules 2, 2a are engaged or disengaged by relative vertical displacement. As apparent from the Figures, the arrangement allows for some limited relative rotational or pivotal movement of the two foundation modules 2, 2a in a horizontal plane. The angle of rotational movement permitted is increased by the presence of angled, sloping shoulder portions 66 either side of the male member 4 and, to a lesser extent, by the slightly angled sloping shoulder portions 68 either side of the female recess 6.

Example 5

Referring to Figure 6, a first embodiment of a system in accordance with the present invention comprises two prefabricated foundation modules 2, 2’, and a prefabricated extension module 200. The foundation modules 2, 2’ are formed of reinforced concrete. Each foundation module comprises a plurality of steel rods running along the long axis of the module, with further transverse metal rods substantially at a right angle to the long axis of the foundation module. Each foundation module resembles a ladder, with transverse portions 10 or “rungs” at regular fixed intervals across the module, on which the attachment points are provided. Between neighbouring rungs is an aperture, such that a plurality of apertures is formed in each foundation module. In the illustrated embodiment these apertures are positioned along the of the module

One purpose of the apertures provided in the foundation module is to facilitate access to services located beneath the module, thereby limiting inspection, maintenance or repair of the services as required. Another purpose of the apertures is to facilitate drainage of rainwater or the like.

The end of the module 2, and the end of the module 2’, are shaped and dimensioned so as to form a co-operating engagement therebetween, in the absence of the extension module 200. Each foundation module 2, 2’ is substantially rectilinear and approximately 6 m in length.

The attachment points on the foundation module may be of any convenient type. In the embodiment illustrated, a hole or socket (not shown) is formed or provided in each of a plurality of the transverse rungs 10 of the foundation modules. Each hole or socket is able to receive a substantially vertical support post, to which post a vehicle restraint barrier may be attached by conventional means.

The extension module 200 is shaped and dimensioned to fit between, and engage with, the otherwise adjacent ends of the foundation modules 2, 2’. Accordingly, in the illustrated embodiment, one side of the extension module 200 is provided with a recess or groove 199 which accommodates a cooperatively shaped projecting portion 4 on the end of the foundation module 2, and the opposite side of the extension module 200 is formed with a projecting portion 201 which is received within a cooperating recess or groove 6 in the end of the foundation module 2’. It will be apparent that, in the embodiment illustrated in Figure 6, an extension module may be positioned at the end of each foundation module 2. Alternatively, fewer extension modules may be employed, such that at some locations neighbouring foundation modules 2 will directly engage with one another.

In the embodiment shown in Figure 6, the extension module 200 is provided with a single attachment point for attachment thereto of a lighting column 208 for a street light. The size and shape of the extension module is such that the attachment point, and the lighting column attached thereto, may be set back from the vehicle restraint barrier by a desired amount. Accordingly, in the event of a vehicle impacting, and deforming, the vehicle restraint barrier, the lighting column is set back sufficiently such that it will not cause injury to any occupants of the vehicle.

A second embodiment of a system in accordance with the invention is shown in Figure 7. A third embodiment of a system in accordance with the invention is shown in Figure 8. The embodiments are generally similar to that illustrated in Figure 6 and like components are denoted by common reference numerals. In Figure 7, the extension module 200 is formed with a parallel-sided groove in its upper surface. When placed in combination with an overlying foundation module 2, the groove in the upper surface of the extension module 200 accommodates part of the foundation module. In addition, a square or rectangular shaped raised portion 203 at one end of the extension module is snugly received within a co-operatively shaped aperture in the foundation module. In this way a close-fitting engagement is created between the extension module 200 and the overlying foundation module 2. In the illustrated embodiment, the extension module 200 has an attachment point for a lighting column 208 for a street light. The shape of the extension module is such that, when in situ , is set back from a vehicle restraint system mounted on the foundation module 2. It will also be appreciated that the foundation module comprises a second aperture which is co-operatively shaped to engage with extension module 200. As a result, the extension module 200 can be positioned towards either end of the foundation module 2; alternatively, two separate (but substantially identical) extension modules 200 may be positioned in engagement with a single foundation module 2.

Referring to Figure 8, the illustrated embodiment is essentially the reverse of that shown in the preceding Figure. Thus, the extension module 200 overlies the foundation module 2. At one end region of the underside of the extension module 200 is a square or rectangular downward-projecting portion, which is snugly received within a co-operatively shaped aperture formed in the foundation module 2, such that the extension module 200 and the foundation module 2 are in a close-fitting frictional engagement. In addition, the main body of the extension module 200 butts up in contact with the exterior surface of the foundation module 2.

Example 6

Figure 9 shows a perspective view of a system in accordance with an aspect of the invention, in situ along the edge of a carriageway 30, with an installed vehicle restraint system 22 together with various installed items of street furniture. The system is broadly similar to that shown in Figure 4, and like components are denoted by common reference numerals.

The installation system comprises two foundation modules 2, 2’ an extension module 200 located between the two foundation modules 2, T and a pre-fabricated services conduit unit 32 beneath the foundation module. The conduit unit 32 has a cross- section resembling conjoined adjacent letters “n” and “u”, such that the conduit unit substantially possesses rotational symmetry of order 2 about its long axis. The conduit unit is conveniently formed of concrete. The “n” shaped part 34 of the conduit unit 32 forms a protective arch over services 36, laid beneath the conduit unit. The services may comprise, for example, electrical cables, gas pipes and the like.

The “u” shaped part 38 of the conduit unit 32 forms a drainage channel to drain away surface water which falls onto the structure or which drains onto the structure from the surface of the carriageway 30, which is substantially flush with the top of the foundation module 2. In this way, the system can help reduce the build-up of standing water on the surface of the carriageway.

Each foundation module 2, T comprises a plurality of attachment points for respective support posts 20, to which posts 20 a horizontal steel barrier 22 of a vehicle restraint system (VRS) is attached. In addition to the VRS attachment points, the foundation modules 2, 2’ comprise a plurality of further attachment points to which various items of street furniture are attached. These items of street furniture include a pedestrian safety fence 202, a yardage counter 204, and an acoustic damping fence 206. These items of street furniture are all on the far side of the vehicle restraint system relative to the carriageway 30. The edge of the foundation modules 2, 2’ nearest to the carriageway 30 is formed with a plurality of drainage perforations 210, which permit drainage of surface water from the carriageway 30 into the drainage channel of the conduit unit 32.

The extension module 200 is shaped and dimensioned so as to co-operate with the respective end portions of the two foundation modules 2, so as to engage with each thereof. The extension module 200 has an attachment point for a lighting column 208.