Abstract:
A roadside barrier which has underlying concrete support blocks, a mesh fence, optionally including overlying transparent sheet material, which is erected on the blocks, and a deterrent, sloping mesh-material, surface, which hinders human access, at a base of the fence on the support blocks.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a barrier. 
     The invention finds particular application in the provision of the barrier adjacent a road or a traffic lane or on a side of a bridge. These applications are however exemplary only and are non-limiting. 
     A bridge which is high and which spans a considerable distance can represent a substantial engineering feat. A bridge of this kind, for example crossing water which separates populated islands, or an island from a mainland, or which traverses dramatic mountain scenery, can attract considerable attention. Persons crossing the bridge on foot or in vehicles inevitably want to take advantage of the view afforded by being on the bridge. This type of visual capability should not however be at the expense of personal safety and, more particularly, it should not be easily possible for a person on the bridge to cross over a side of the bridge and intentionally or negligently put himself in a position of danger. For this reason the use of a barrier along at least one side of the bridge is desirable, if not essential. 
     Appropriate barriers are also used to demarcate a roadway. For example, concrete blocks are commonly used to separate traffic flow in one direction from traffic flow in an opposing direction. Similar blocks are also used, primarily for safety reason, to prevent or restrict pedestrians from crossing highways or freeways. 
     One type of structure which is at least partly suitable for the aforementioned purposes is formed from a number of precast concrete blocks, referred to as “New Jersey blocks”, which are manufactured off-site and which are thereafter positioned on a roadway according to requirement e.g. on one side of a bridge or between or alongside traffic lanes. The blocks are substantial and generally can withstand the impact of a motor vehicle. However the blocks are not particularly high and cannot effectively prevent a pedestrian from climbing over the blocks to gain access to a traffic lane. 
     If a fence is erected on top of a structure of the aforementioned kind then, despite the impeding effect of the fence, a determined person can, by standing on top of the structure, get a secure foothold to climb over the fence. 
     An object of the present invention is to address, at least to some extent, the aforementioned situations. 
     SUMMARY OF THE INVENTION 
     The invention provides a barrier which comprises underlying support structure and a fence, wherein the fence includes a plurality of spaced apart, generally vertically extending, posts, each post including an elongate body with a respective lower end which is engaged with the support structure and an upper end, a plurality of mesh panels, each mesh panel comprising mesh structure with opposed first and second vertical edges and opposed upper and lower horizontal edges, each panel being located between a respective adjacent pair of posts with the first and second vertical edges respectively secured to the posts, and a deterrent arrangement, at least on one side of the panels, adjacent the lower horizontal edges of the panels, which restricts access to the panels. 
     A respective deterrent arrangement may be positioned on each side of the panels. 
     The deterrent arrangement may be of any suitable kind which can restrict access to the panels. Generally the deterrent arrangement, apart from restricting access, should make it difficult for a person to climb over a mesh panel. 
     In one form of the invention the deterrent arrangement includes a plurality of upwardly extending spikes. The underlying support structure may include an upper surface and the spikes may be fixed to such upper surface but spaced from the lower horizontal edges of the panels so that a person, approaching the panels, cannot with ease stand on the upper surface adjacent the panels. 
     In a different form of the invention the deterrent arrangement includes sheet-like material which is inclined to the vertical and which is positioned adjacent a respective lower region of each panel. The sheet-like material may comprise mesh sections, typically in planar form. Each section may be positioned adjacent a lower horizontal edge of a panel and may be inclined to the vertical. Each section may extend downwardly and away from the respective lower horizontal edge of the panel. 
     These mesh sections are preferably fixed to the underlying support structure. 
     The support structure may comprise an elongate cementitious ground-engaging body with such upper surface. 
     The cementitious body may be of any appropriate kind and for example may comprise precast concrete blocks e.g. of the New Jersey type, a concrete slab constructed for the purpose or a wall made, for example, in a conventional way from brick and mortar. In this respect “cementitious” is to be given a wide meaning. 
     In one form of the invention the mesh structure of a fence panel includes a first mesh section with a first mesh density and a second mesh section with a second mesh density, and sheet material is fixed to the mesh structure and overlies at least part of the second mesh section. 
     The second mesh density may be less than the first mesh density and, preferably, the size of each aperture in the second mesh section is greater than the size of each aperture in the first mesh section. 
     The sheet material is preferably continuous i.e. it is solid and does not have apertures. The sheet material may be transparent so that it does not meaningfully obstruct visibility. The sheet material may be positioned, relative to the ground, at a convenient height so that a person near the fence will be able to see through the sheet material. 
     If the second mesh section has a relatively large aperture size, the second mesh section may be relatively weak compared to the first mesh section. The addition of the sheet material to the second mesh section can strengthen the second mesh section. 
     At least part of the first mesh section may lie in a plane which is inclined to the vertical i.e. to a plane which is occupied at least by the second mesh section. Such inclined part of the first mesh section then acts as said deterrent arrangement. 
     In one form of the invention each post is shaped to engage with a side, and with the upper surface, of the support structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is further described by way of examples with reference to the accompanying drawings in which: 
         FIG. 1  is a side view of a barrier according to one form of the invention; 
         FIG. 2  is a cross-sectional view of the barrier taken on a line  2 - 2  in  FIG. 1 ; 
         FIG. 3  is a view on an enlarged scale of a lower portion of the barrier which is enclosed in a circle marked  3  in  FIG. 2 ; 
         FIGS. 4, 5 and 6  are views respectively corresponding generally to  FIGS. 1, 2 and 3  but illustrating a barrier according to a second form of the invention; 
         FIG. 7  is a view in perspective of part of a barrier according to another form of the invention; 
         FIG. 7A  is a view of a post between adjacent flanges; 
         FIG. 8  is a side view on an enlarged scale, compared to the scale in  FIG. 7 , of a fence included in the barrier of  FIG. 7 ; and 
         FIG. 9  is a view in cross-section taken on a line  9 - 9  in  FIG. 8  of a mesh panel which is included in the fence. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIG. 1  of the accompanying drawings illustrates from one side a portion of an elongate barrier  10  according to one form of the invention. The barrier  10  includes underlying structure  11  comprising a plurality of precast cementitious blocks  12  which are positioned adjacent one another, following a defined path, on a roadway  14 . Typically the blocks  12  are of the kind known as New Jersey blocks and they extend on a side of a highway, or on a highway to separate traffic flow in one direction from traffic flow in an opposing direction. 
     The barrier  10  further includes a fence  16  which is erected on top of the blocks  12 . The fence is formed from a plurality of fence posts  18  which are spaced apart from each other, at regular intervals, by a distance  20 . Mesh panels  22  are respectively located between and fixed to each adjacent pair of posts. 
     Each panel  22  comprising a respective rectangular mesh structure which is formed with appropriate mesh apertures and includes an upper horizontal edge  24 , a lower horizontal edge  26 , and opposed first and second vertical edges  28  and  30  respectively. 
     As appropriate, according to requirement, lamp posts  34  are fixed at intervals to the blocks. 
       FIG. 2  is a view in cross-section, on a slightly enlarged scale, of the barrier  10  taken on a line  2 - 2  in  FIG. 1 .  FIG. 3  shows on an enlarged scale an intermediate portion, enclosed in a circle marked  3 , of the construction in  FIG. 2 . 
     The blocks  12  form a flat upper surface  40  which facilitates erection of the fence  16 . Each post  18  comprises an elongate member  41  to which is fixed a respective base plate  42  which, through the use of appropriate fasteners  44 , is securely anchored to the upper surface  40 . 
     The mesh panels  22  are substantially identical to one another. Each panel has respective flanges  46  and  48  at its vertical edges  28  and  30  respectively.  FIG. 3  shows a flange  46  abutting a post  18 . The flange is fixed to the post using suitable fasteners  50 . 
     The panel  22  is stiffened in a horizontal direction i.e. against flexure about a vertical axis, by means of one or more reinforcing ribs  52  which extend horizontally. Each rib is defined by a V-shaped channel formed by bending the mesh under factory conditions. Similarly, the lower edge  26  is stiffened by means of a flange (not shown). The upper edge  22  is also stiffened by means of a flange which is similar to the flange. 
     The dimensions of the upper surface  40  are such that a person could stand on the upper surface and grip the adjacent mesh panel. The person could possibly thereby get sufficient support to climb over the panel. To obviate or to hinder this, in the  FIG. 2  arrangement use is made of a deterrent arrangement  56  on one side of the fence and a substantially similar deterrent arrangement  58  on an opposing side of the fence. Each deterrent arrangement comprises a plurality of elongate spikes  60 . The spikes are provided in strip form and each strip is fixed, generally parallel to the fence  16 , to the upper surface  40  using fasteners  62 . The spikes are sharp and a person trying to stand on top of the concrete blocks would find it uncomfortable or even dangerous and, in this way, the person would generally be deterred from trying to climb over the fence. 
       FIGS. 4, 5 and 6  are similar to  FIGS. 1, 2 and 3  respectively and illustrate a barrier  10 A according to a different form of the invention. There are substantial similarities between the barrier  10  and the barrier  10 A and for this reason the barrier  10 A is not described in detail. Where applicable like reference numerals are used to designate like components. 
     In the barrier  10 A the deterrent strips of spikes ( 56 ,  58 ) are replaced by a deterrent arrangement  70  which is shown, more clearly, in  FIG. 6 . The deterrent arrangement  70  includes mesh sections  72  and  74 , in sheet (planar) form which are generally identical but which are erected in opposing orientations. 
     Lower edges  26  of the mesh panels, which make up the fence  16 , could rest on the flat upper surface  40  of the concrete blocks. Preferably though, to increase the height of the fence  16  without using additional material, the lower edges are spaced from the surface  40  by a distance  76 . The mesh sections  72  and  74  are secured, at their upper edges  80 , by means of suitable fasteners  84  to the mesh panels adjacent the lower edges  26 . The sections  72  and  74  extend downwardly and outwardly to lower horizontal flange sections  72 A and  74 A respectively which are directly fixed, by means of appropriate fasteners  86 , to the upper surface  40 . 
     The mesh sections  72  and  74  have outwardly and downwardly extending surfaces which effectively cover the flat upper surface  40  of the concrete blocks. A person, who attempts to stand over the blocks in order to grip and then climb over a mesh panel, would find it difficult to stand on the sloping surface of a mesh section and, in this way, would generally be deterred from trying to climb over the mesh panel. 
       FIG. 7  illustrates in perspective portion of a barrier  110  according to another form of the invention. 
     Typically the barrier  110  is on one side of a roadway  112  which is formed on a bridge or similar elevated construction. Usually, if the bridge is a high rise bridge in an attractive or interesting area, a person on the roadway  112  would be afforded a good view of the surroundings. The barrier  110  is designed to act as a safety arrangement in that it makes it difficult for a person to leave the roadway or the bridge except at designated points, but without unduly interfering with the view which is available to a person on the bridge. 
     The barrier  110  includes underlying support structure  114  and a fence  116 . The support structure is made from precast concrete blocks which are placed in situ, as required, or from concrete which is cast in situ. The support structure has an inner side  118 , an outer side  120  and an upper surface  122 . A lower end  124  of the support structure rests on the ground or is engaged therewith in any appropriate manner. 
     The support structure has a height  130 . The dimensions and mass of the support structure are such that the structure is capable of resisting an impact which may arise from a vehicle traversing the roadway  112 . 
     The fence  110  includes a plurality of generally vertically extending fence posts  134  which are regularly spaced apart from one another by a distance  136 . Secured to the fence posts are a number of mesh panels  138 . The mesh panels are substantially identical to one another. Each mesh panel, see in addition  FIG. 8 , is made from a rectangular mesh structure which includes opposed first and second vertically extending edges  140  and  142  and opposed horizontally extending lower and upper edges  144  and  146  respectively. 
     The fence panel  138  includes a lower, first, mesh section  150 , an intermediate, second, mesh section  152  and an upper, third, mesh section  154 . Referring as well to  FIG. 9 , a lower portion of the first mesh section  150 , which is bounded by the lower edge  144  of the panel, lies in a first plane  160 . An upper part  164  of the first mesh section lies in a second plane  166  which is inclined at an angle  168  to the first plane. The second mesh section  152  and the third mesh section  154  lie in the plane  166 . In use of the fence panel  138  the plane  166  is generally vertical and the plane  160  is inclined to the vertical. 
     The first mesh section  150  has a relatively high mesh density compared to the second mesh section  152  i.e. the sizes of its apertures  170  are relatively small compared to the size of each aperture  172  in the second mesh section. This means that the first mesh section is substantially stronger than the second mesh section. The third mesh section  154  is typically of the same mesh density as the first mesh section. 
     The second mesh section  152 , see  FIG. 9 , is strengthened by means of horizontally extending reinforcing ribs  174  and  176  respectively which are formed by bending vertical wires of the mesh into a V-shape. These reinforcing ribs are respectively at a boundary of the second mesh section and the first mesh section, and at a boundary of the second mesh section and the third mesh section. 
     Sheet material  178  is attached to the second mesh section by means of suitable fasteners  180  which are only notionally shown in  FIG. 7 . The sheet material is typically solid i.e. without apertures, clear or transparent polycarbonate with an appropriate thickness. The polycarbonate material is tough and weather resistant and, when attached to the panel, substantially strengthens the second mesh section. The aperture size of the second mesh section is such that the wires in the section do not unduly interfere with visibility i.e. a see-through capability. The polycarbonate panel attached to the second mesh section ensures that the visibility factor is not adversely affected but the strength of the second mesh section is significantly enhanced. 
     The vertical edges  140  and  142  of the panel are formed with respective flanges  182 —see  FIG. 9  which illustrates one flange only. Each flange  182 , when the panel  138  is positioned between adjacent fence posts  134  as shown in  FIG. 7  abuts a respective post  134  and is attached to the fence post by means of appropriate fasteners  72  which pass through the flange and which are engaged with the post—see  FIG. 7A  which shows a post  134  between adjacent flanges  182 . 
     Each post  134  is shaped in a complementary manner to the profile shown in  FIG. 9 . Thus each post has a vertical section  134 A, a sloping section  134 B, a section  134 C which is designed to lie flat on the upper surface  122  of the support structure, and a relatively short section  134 D which extends downwardly and which abuts the side  118  of the support structure. The section  134 A lies in the plane  166  and the mesh sections  164 ,  152  and  154  are attached thereto. The section  134 B lies in the plane  160  and the mesh section  150  is, in use, secured thereto. The sections  134 C and  134 B, which are at a right angle to each other, provide a means whereby the fence post can be securely and relatively easily attached to the support structure  114  in the manner shown in  FIG. 7  through the use of appropriate fasteners  184 . 
     The barrier  110  is of composite construction. The fence which is designed to fit securely and closely on top of the support structure, ensures that the effective height of the barrier  110  is increased substantially above the height  130 . The increase in height means that it is difficult for a person, on the roadway, to climb over the barrier. On the other hand the transparent sheet material which is positioned in a horizontally extending band at an intermediate location of the fence stiffens the mesh over that portion thereof which is of reduced mesh density, but does not impede visibility. 
     The barrier  110  is suitable for use on a bridge or similar roadway. The barrier can however be used in other applications in order to create a controlled environment on one side of the barrier, without interfering with visibility through the barrier. Thus the barrier  110  could be positioned between two traffic lanes to allow a see-through capability. 
     The deterrent arrangement at the base of the fence makes it difficult for a person to climb over the fence. The deterrent arrangement, in each embodiment, could include spikes, or an inclined mesh section, or both, on one side or both sides of the fence, at its lower edge, adjacent the upper surface of the concrete support structure.