In the traffic environment, poles carrying signs, street lights, traffic lights, road portals, and railings, are vital for providing safety and convenience to the drivers of vehicles, cyclists, and pedestrians. Such poles are typically anchored in a hole dug in the ground or in a subsoil anchoring element of concrete or similar material, or bolted to an anchoring element, road or pavement surface. Due to the loads carried by the pole, which in addition to the burden of a traffic light, a sign, a lamp, etc., also includes environmental loads such as snow loads and wind loads, both pole and anchoring must be of sufficient strength to ensure that the pole remains functional.

An inherent drawback of poles designed from parameters of load bearing capacity solely, when used in the traffic environment, is that they are unyielding, thereby aggravating the risk of grave injury to the occupants of a vehicle running off the road and hitting such a pole.

To ameliorate this situation, yieldable poles, also called safety poles have been invented. Yieldable poles typically employ special features to provide the necessary strength to carry normal loads, i.e. the sum of environmental loads and the load of a traffic light, sign, lamp, etc., under normal conditions, while simultaneously being capable of yielding when hit by a vehicle. Features currently employed include local weakenings or reinforcements such as slots, slits, grooves, stiffening rods, and/or specific geometries of the poles, the idea being that these features will allow the pole to deform and thereby dissipate the kinetic energy of the oncoming vehicle in a controlla- ble manner so as to subject the occupants of the vehicle to as limited deceleration as possible, while still arresting the motion of the vehicle.

Within the field of poles for use in the traffic environment, yieldable poles have been disclosed in amongst others US3987593, US4630413, WO9801626, and WO2006093415.

The above mentioned documents describe yieldable poles comprising local weakenings, local reinforcements, and/or specific geometries to achieve a yielding effect. Although the described poles may be able to yield as intended when hit by a vehicle, the desired decelerating effect caused by the yielding pole will be absent if the base of the pole does not remain firmly anchored during the collision and the subsequent yielding of the pole.

Anchoring devices for poles are described in amongst others DE19523173, GB2324321 , US5625988, and US20060104715.

The above mentioned documents describe ground sleeves for placement in the ground, either directly in a dug hole, or in a dug hole filled with uncured concrete, said concrete being cured after the ground sleeve is positioned in the hole. After the ground sleeve is fixated, the bottom of the pole is inserted in the sleeve and locked in place. The described ground sleeves are not suitable for firmly retaining the base of a yielda- ble pole, and the stability and load bearing capacity of poles mounted in such ground sleeves will to a high extent depend on the ground conditions at the site of the pole and/or the nature of the cast concrete surrounding the ground sleeve.

If the pole is to be anchored in an anchoring element such as a cast element on the other hand, the casting process may lead to undesired irregularities in dimensions or surface evenness, in the channel where the pole is to be anchored, and therefore any device for securing the base of a pole in a channel of a cast element must be able to compensate, for example by being of a resilient material, which results in a less secure anchoring of the pole.

An object of the present invention is to provide an anchoring assembly which may be used to securely anchor a pole in a channel in an anchoring element, thereby elimi- nating or at least substantially reducing the risk of the pole being drawn out of the channel during a collision.

A further advantage according to the present invention is that the pole may be easily installed and righted to a vertical position in the anchoring element. It is therefore an object of the present invention to provide a method of anchoring a pole in an anchoring element using the anchoring assembly.

A further advantage according to the present invention is that the pole may be securely held also in channels in anchoring elements having irregularities in dimensions or surface evenness due to the casting processes. An additional advantage of the anchoring assembly according to the present invention is that forces acting on the pole are transferred in a well defined manner by the anchoring assembly to the anchoring element, facilitating the calculations necessary to determine the appropriate dimensions of the anchoring element and the pole of a for example a street light pole installation.

A further object of the present invention is to provide a yieldable pole.

A further object of the present invention is to provide a safety traffic pole system com- prising a yieldable pole and an anchoring assembly whereby a yieldable pole may be securely and easily anchored to an anchoring element.

The above objects, together with numerous other objects which will be evident from the below detailed description of preferred embodiments of the anchoring assembly according to the present invention, are according to a first aspect of the present invention obtained by an anchoring assembly for anchoring a pole within a channel in an anchoring element, comprising a first retaining element and a second retaining element, each of the retaining elements being segmented in at least three interconnected parts.

The pole is typically a pole or a post carrying a load. Possible loads may be a sign, a traffic light, a street light, a road portal, a railing etc. The pole may be placed in the traffic environment but may also be placed in a park, or in a garden. The pole is preferably a yieldable pole of the type comprising reinforcing rods corresponding to chan- nels formed in the inner walls of the pole along the direction of the pole, but may also be an ordinary, non-yieldable pole. The pole may be constructed from metal such as aluminum, steel, etc., or from plastics including fiber reinforced plastics. The pole may be formed through an extrusion process. The pole is preferably hollow so that electrical wires may be led through the pole if the poles carry a load such as a street light etc. The pole may consist of several pole sections connected to one another. The pole may have a round, elliptical or polygonal cross section.

The anchoring element is preferably a precast element, for example an element cast in a mold to a specific shape, the precast element then being easily and quickly installed in a hole in the ground or the like. However, the anchoring element may also be a cast element such as an element cast by pouring a suitable casting mass, such as con- crete, into a hole in the ground or the like. Other examples of anchoring elements include a pavement slab, a road surface, a cliff, a boulder, bedrock, or a building element etc.

The channel is typically a cylindrical channel, but the channel may also be elliptic cylindrical or polygonal cylindrical. The channel has a first diameter and a second diameter, the transition from the first diameter to the second diameter being achieved through a restriction. The restriction may be an instantaneous transition from a first diameter to a second diameter, but is preferably a frustoconical restriction having a diameter changing from the first diameter to the second diameter in a linear manner. In other embodiments the restriction may include a square or cubic transition from the first diameter to the second diameter.

Preferably the first diameter, corresponding to the diameter of the channel between the channel opening and the restriction, is larger than the second diameter corresponding to the diameter of the channel between the restriction and the channel bottom. The channel has a channel opening on a surface of the anchoring element, and channel bottom at the opposite end of the channel.

When the anchoring element is a precast element, it is typically cast in the shape of a plinth having a widened base, an upper surface opposite the base, and a channel extending from an opening in the upper surface into the interior of the precast element for receiving an elongated object. The precast element is typically of polygonal cross section, but may also have a round or square cross section.

The material used for the anchoring element may be stone, plastic or concrete, plastic and concrete possibly being reinforced with rebar or fibers.

The first retaining element is segmented in at least three interconnected parts, the in- terconnected parts preferably being segments held in coordinated relationship with their neighboring segments by a ring. The number of segments is preferably four, but may be from three to ten. Each segment typically has an inner wall for engaging the pole and an outer wall for engaging the inner walls of the channel. The ring may be a ring connected to the undersides of the segments, or provided as an integral part of the first retaining element, as a full ring, or as connecting material between segments only, for example when the first retaining element is produced by molding. The first retaining element may be cylindrical, elliptic cylindrical, polygonal cylindrical or frustoconical as long as a strong engagement is achieved between the channel and the outer retaining element; however, a cylindrical shape is preferred.

It is preferred that the shape formed by the inner walls of the first retaining element is complimentary to the cross section of the pole, especially an octagonal shape, so as to engage a pole of octagonal cross section, is preferred.

Preferably the first retaining element is fabricated from a strong material with slight resilience for example, plastic, fiber reinforced plastic, high density rubber, wood, aluminum etc., the advantage being that any irregularities, due to the casting process, in the precast element channel, such as for example in the diameter, roundness or the smoothness of the walls of the channel, may be compensated for.

The first retaining element fixates the pole lower part within the channel and serves to transfer transverse forces acting on the pole to the anchoring element. Furthermore, the first retaining element may serve to achieve a vertical positioning, i.e. righting the pole so that it stands vertically, of the pole or to adjust the positioning by displacing individual segments along the axis of the pole, or by moving one or several segments along the curvature of the pole, when the pole is within the channel. To facilitate such displacement of individual segments, the ring holding the segments in coordinated relationship may be of flexible material, or may be breakable so as to allow individual placement of the segments of the outer retaining element. At the same time the ring facilitates the installation of the outer retaining element around the pole lower part in the channel by its coordinating effect on the segments. A further advantage of the first retaining element being segmented in at least three interconnected parts is that the friction, and thus the force necessary during installation of the pole in the channel, may be reduced in comparison with a non-segmented retaining element.

The second retaining element is segmented in at least three interconnected parts, the interconnected parts preferably being segments joined by, and being perpendicular to, an annular washer.

The number of segments is preferably four, but may be from three to ten. Each segment typically has an inner wall for engaging the pole and an outer wall for engaging the inner walls of the channel. The segments are preferably joined perpendicularly to an annular washer by the bottom part of each segment. Preferably, the segments are provided on the periphery of the washer so that the central areas of the washer may form a pole supporting surface to engage the end of the pole axially. Preferably, the width of the pole supporting surface at least corresponds to the thickness of the pole wall. Each segment outer wall is preferably tapered so that the second retaining element is frustoconical.

The washer may be provided as a separate part, possibly of a different material than the segments, to which the segments have been joined, or provided as an integral part of the second retaining element such as for example when the second retaining element is produced by molding.

The second retaining element may be cylindrical, elliptic cylindrical, polygonal cylin- drical or frustoconical as long as a strong engagement is achieved between the channel and the inner retaining element; however, a frustoconical shape is preferred. The shape formed by the inner walls may be cylindrical, elliptical or polygonal as long as a tight fit is achieved between the inner walls and the pole. It is preferred that the shape formed by the inner walls of the inner retaining element is complimentary to the cross section of the pole, especially an octagonal shape, so as to engage a pole of octagonal cross section, is preferred.

The second retaining element is preferably made of plastic, high density rubber, wood aluminum other metals etc, but a strong material with a slight resilience is preferred as inner retaining elements made from such materials may better adapt to irregularities in the channel due to the casting process.

In some embodiments according to the present invention the washer may be in the form of a solid disc, possibly having an aperture for passing an electric wire through the washer and further into the pole for supplying power to a street light or similar carried by the pole.

The second retaining element fixates and centers the pole base end within the channel of the anchoring element, preferably within the channel restriction, and transfers trans- verse forces acting on the pole as well as axial forces from for example a load carried by the pole to the precast element. Axial forces from the load carried by the pole forces the second retaining element towards the channel bottom. As the outer walls of the second retaining element engage the inner walls of the channel restriction, the inner walls of the second retaining element exert a clamping force on the pole base end to securely anchor the pole within the channel. In the event that the pole is hit by a vehicle, the clamping force from the segments of the second retaining element ensures that the pole is prevented from being drawn out of the channel during the collision. Furthermore, transverse forces from the collision transferred to the segments of the second retaining element result in an increased friction between the outer walls of the second retaining element and the inner walls of the restriction, which may further increase the effectiveness of the second retaining element in preventing the pole lower part from being drawn out of the anchoring element. Further, it is contemplated that the engagement between the pole base end and the inner walls of the second retaining element, and between the outer walls of the second retaining element and the inner walls of the channel restriction, may on one hand be made sufficiently strong to prevent the pole from being drawn out of the anchoring element during a collision involving transverse forces acting on the pole, while on the other hand be sufficiently weak to allow easy removal and installation of the pole in normal conditions where the transverse forces acting on the pole are negligible.

It is preferred that the second retaining element has a frustoconical shape, and that the restriction in the channel in the anchoring element also is frustoconical so that a tight engagement between the two is achieved, however, a second retaining element having a frustoconical shape may also achieve an especially strong engagement with a restriction having an instantaneous transition from the first diameter to the second diameter due to the wedging properties of the segments of the second retaining element, and this may be preferred in some embodiments.

During installation of the pole in the anchoring element, the first retaining element is preferably guided onto the pole lower part, and the pole base end is seated in the second retaining element, before the pole is forced into the channel of the anchoring element.

Preferably the tight engagement of the outer walls of the first retaining element necessitate the application of some force such as for example by a hammer and chisel or other suitable tool on the top surface of each segment, either simultaneously for all segments or sequentially, to drive the first retaining collar inwards to a suitable posi- tion, such as a position within the half of the channel between the channel opening and the channel restriction. Alternatively, the first retaining element may be fitted so snugly on the pole lower part that the action of forcing the pole lower part into the channel in the anchoring element also forces the first retaining element into a suitable position in the channel, such as a position within the half of the channel between the channel opening and the channel restriction.

The second retaining element is preferably forced into a suitable position, preferably within the restriction, by the force applied to the pole when the pole is forced into the channel of the anchoring element.

An advantage of the second retaining element being segmented in at least three interconnected parts is that the friction, and thus the force necessary during installation of the pole in the channel, may be reduced in comparison with a non-segmented retain- ing element.

According to a second aspect of the present invention, a method is provided for anchoring a pole in an anchoring element comprising the use of an anchoring assembly according to the first aspect of the present invention. By using the anchoring assembly of the present invention to anchor the pole to the precast element a secure and simple anchoring may be achieved.

The pole is preferably a yieldable pole comprising longitudinally extending reinforcement rods corresponding to channels formed in the inner walls of the pole. The anchoring assembly according to the second aspect of the present invention ensures that the yieldable pole is not drawn out of the precast element during a collision. This further enhances the beneficial properties of the yieldable pole in arresting the motion of a vehicle colliding with the yieldable pole.

According to a third aspect of the present invention, a pole carrying a load is provided, the pole comprising longitudinally extending reinforcement rods corresponding to channels formed in the inner walls of the pole. The load may be a traffic sign, a street light, a traffic light, a road portal, a railing or the like.

By the reinforcing effect of the reinforcement rods the pole is made sufficiently strong to carry the load during normal conditions; however, in the event that the pole is hit by a vehicle, the deformation of the pole deforms the channels in the inner walls, which annuls the reinforcing effect of the reinforcement rods as they are no longer connected to the pole wall, thus rendering the pole more easily deformable.

The reinforcement rods are preferably made of steel, iron, aluminum or carbon fibre, and may have any shape of cross section corresponding to the cross section of the channels formed in the inner walls of the pole; examples include rectangular, square, circular or elliptical cross section. The channels formed in the inner walls of the pole may take any form or be replaced by glue, rivets, welds, screws etc., as long as the function of a breakable connection between the reinforcement rods and the inner walls of the pole is achieved.

According to a fourth aspect of the present invention a safety traffic pole system is provided comprising the combination of the pole according to the third aspect of the present invention and an anchoring assembly according to the first aspect of the present invention.

The safety traffic pole system according to the fourth aspect of the present invention thus provides a system having improved safety and ease of deployment.

In the present context the term "tapered" should have the meaning of having varying thickness or circumference along an axis perpendicular to the plane in which said thickness or circumference is determined.

The invention and its many advantages will be described in more detail below with reference to the accompanying schematic drawings, which for the purpose of illustration show some non-limiting embodiments and in which

Fig. 1 shows a pole anchored in a subsoil precast element by the anchoring assembly of the present invention.

Fig. 2 shows a cut away view of a pole anchored in a precast element by the anchoring assembly of the present invention.

Fig. 3 shows a top view of a cover element. Fig. 4 shows a side view of a cover element.

Fig. 5 shows a perspective view of a cover element.

Fig. 6 shows a first retaining element.

Fig. 7 shows a second retaining element.

Fig. 8 shows a second retaining element engaging the base end of a pole.

Fig. 9 shows a cross section of a yieldable pole.

Fig. 10 shows a sign mounted to a pole.

Fig. 1 and Fig. 2 show a pole, in its whole designated the reference numeral 24 carrying a load in the form of a sign 26. Numerous other loads may be carried by pole 24, for example a street light, a road portal, a rail etc. The pole 24 is shown anchored in a precast element 8, in its whole designated the reference numeral 8, by an anchoring assembly comprising a first retaining element 4 and a second retaining element 6. A cover element 2 is also shown. The precast element 8 comprises a base 9, an upper part 7, a channel 12 for receiving the pole lower part 23, and a channel opening 14. The precast element 8 may be erected in a hole dug in the ground and surrounded by fill mass 10, which may comprise soil, gravel, sand or concrete. The channel 12 further comprises a channel bottom 16, and between the channel opening 14 and the channel bottom 16 a frustoconical channel restriction 18 is provided. The pole lower part 23 is anchored in the channel 12 by the second retaining element 6 which is frustoconical and fits tightly within the channel restriction 18, and by the first retaining element 4 situated within the channel 12 near the channel opening 14. The cover element 2 is partially inserted into the channel opening 14. The precast element 8 is further shown (Fig. 1 only) comprising a utility duct 20 for communication between the channel bottom 16 and the outer surface of the precast element. Utility duct 20 may be used for connecting electrical wires for e.g. sign lighting, or when the load carried by the pole is a street light or traffic light. The pole 24 is preferably hollow or comprises channels for electrical wires (not shown). A pole top cover 28 closes the end of the pole at or above the sign 26. Fig. 3-5 shows a cover element in its whole designated the reference numeral 2, comprising a disc 30 having a diameter which at least corresponds to the greatest width of the upper part 7 of the precast element 8, an aperture 32 of dimensions and shape so as to correspond to the cross section of the pole 24, and a collar 34, shown in Fig 4 and 5, of appropriate dimensions and shape so as to be insertable into the channel 12 of the precast element 8 through the channel opening 14, and having a tight fit when so inserted. The aperture 32 is shown as octagonal with every second side being rounded, but other shapes, corresponding to other pole cross sections may be ad- vantageous in certain applications. The disc 30 protects the entrance to the channel 12 from the ingress of water, dirt and the like and thus prevents corrosion of the pole 24 and any electrical wires or electrical connections residing in the channel bottom 16 or in the utility duct 20. The collar 34 further aids in achieving a seal of the channel opening 14, but may also, depending on its material properties, serve to transfer transverse forces acting on the pole 24 to the precast element 8. However, a resilient material is preferably used for optimum sealing properties. Suitable resilient materials include different grades of rubber and plastic as well as fiber reinforced rubbers and plastics.

During installation of the pole 24 in the precast element 8, the sealing element 2 is preferably guided onto the pole 24 prior to the insertion of the pole lower part 23 in the precast element channel 12. Force may be applied on the cover element 2 to force the collar 34 to become at least partially inserted in the channel 12.

The disc 30 and the collar 34 are preferably constructed in one piece by for example molding, but may also be manufactured each on their own, if desired from different materials, and then attached to each other to form the cover element 2. The cover element 2 is shown as circular in Fig. 3-5, but may be shaped otherwise, such as for example square, rectangular, triangular or octagonal, provided that an adequate cov- ering of the channel opening 14 and upper part 7 of the precast element 8 is ensured.

Although the cover element 2 shown in Fig. 3-5 is shown having a collar 34 on one side of the disc 30, two collars, one on each side of the disc 30, and possibly having different dimensions so as to be insertable in channels of different diameters in differ- ent precast elements, may be provided. The disc 30 in Fig. 3-5 is shown as circular, but it may be square, rectangular, triangular or octagonal provided that an adequate covering of the channel opening 14 and the upper part 7 of the precast element 8 is ensured. Furthermore, the collar 34 is preferably circular, but may also be square, elliptic or polygonal as long as it is at least partially insertable in the channel 12 of the precast element 8.

Fig. 6 shows a first retaining element, in its whole designated the reference numeral 4, comprising four segments, one of which is designated the reference numeral 36. Each segment 36 has an inner wall 38 for radially engaging the pole lower part 23, and an outer wall 40 for engaging the interior of the channel 12 in the precast element 8. Each segment 4 is held in coordinated relationship with its neighboring segments by ring 42, which is integrally formed with the segments 36 on the underside of the segments 36. The first retaining element 4 fixates the pole lower part 23 within the channel 12 and serves to transfer transverse forces acting on the pole 24 to the precast element 8. Furthermore, the first retaining element may serve to achieve a vertical positioning of the pole 24 or to adjust the positioning by displacing individual segments 36 along the axis of the pole 24, or moving of a segment 36 along the curvature of a pole, when the pole 24 is within the channel 12. To facilitate such displacement of individual segments 36, the ring 42 may be of flexible material, or may be breakable so as to allow individ- ual placement of the segments 36 of the first retaining element 4.

In Fig. 6 the outer walls 40 of the segments 36, of the first retaining element 4, together form a circle when viewed along the axis of the pole, corresponding to a channel 12 of circular cross section, but other shapes, such as for example elliptical, square or rectangular etc., are possible provided that the cross section of the channel 12 is complimentary so as to ensure a tight fit between the channel 12 and the outer walls 40 of the segments 36. Likewise, the shape formed by the inner walls 38 of the segments 36 of the first retaining element 4 may be varied, provided that a tight engagement with the pole lower part 23 is ensured.

The number of segments 36 in the first retaining element 4 in Fig 6 is shown as four, but the number of segments may be varied from three to ten. Further, the segments 36 in Fig 6 are shown as having a uniform size; however, it is possible to use segments having different sizes. During installation of the pole 24 in the precast element 8, the first retaining element 4 is preferably guided onto the pole lower part 23 before the pole lower part 23 is inserted in the precast channel 12. Preferably the tight engagement of the outer walls 40 of the first retaining element 4 with the inner walls of the channel 12 necessitate the application of a force such as for example by a hammer and chisel or other suitable tool on the top surface of each segment 36, either simultaneously for all segments 36 or sequentially, to drive the first retaining element 4 inwards to a suitable position, such as a position within the channel 12 between the channel restriction 18 and the channel opening 14.

Although the first retaining element 4 is shown as having non-tapering outer walls 40, tapering outer walls 40 may also be possible in certain applications.

Fig. 7 shows a second retaining element, in its whole designated the reference num- eral 6, comprising four segments, one of which is designated the reference numeral 44. Each segment has an inner wall 46 for radially engaging the pole base end 25 and an outer tapered wall 48, making the inner retaining element 6 frustoconical, for engaging the interior of the frustoconical channel restriction 18. The segments 44 are joined by, and perpendicular to, an annular washer 50 through the thinnest portion of the segments 44. The annular washer 50 is shown integrally formed with the segments 44 and further comprises a pole supporting surface 52 for axially supporting the pole base end 25.

In Fig. 7 the outer walls 48 of the segments 44 of the second retaining element 6 to- gether form a circle when viewed along the axis of the pole, but other shapes, such as for example elliptical, square or rectangular etc., are possible provided that the cross section of the frustoconical channel restriction 18 is complimentary to ensure a tight fit between the channel restriction 18 and the outer walls 48 of the segments 44. Likewise the shape formed by the inner walls 46 of the segments 44 may be varied pro- vided that a tight engagement with the pole base end 23 is ensured.

Preferably the second retaining element 6 is fabricated from a strong material with slight resilience for example, plastic, fiber reinforced plastic, high density rubber, wood, aluminum etc., the advantage being that any irregularities, due to the casting process, in the frustoconical channel restriction 18, such as for example in the diameter, round- ness, taper or the smoothness of the walls of the channel restriction 18, may be compensated for.

The number of segments 44 in the second retaining element 6 in Fig 7 is shown as four, but the number of segments may be varied from three to ten. Further, the segments 44 in Fig. 7 are shown as having a uniform size; however, it is possible to use segments 44 having different sizes.

The pole supporting surface 52 typically has a width corresponding to at least the thickness of the wall of the pole 24. In some embodiments it may be preferred to use an annular washer 50 being substantially unbroken by apertures etc, i.e. a disc.

Fig. 8 shows a first retaining element 6 engaging a pole base end 25, by the radial engagement of the inner walls 46 of the segments 44, and the axial support of the pole supporting surface 52 on the washer 50. One segment 44 has been cut away to simplify the illustration. The taper of the outer wall 48 is clearly shown. The taper of the outer walls 48 of the segments 44 may vary as long as a strong engagement with the channel restriction 18 is achieved.

The second retaining element 6 fixates and centers the pole base end 25 within the frustoconical channel restriction 18 and transfers transverse forces acting on the pole 24, as well as axial forces from for example a load carried by the pole 24, to the precast element 8. As the second retaining element 6 is forced towards the channel bottom 16 by the axial forces from the pole 24, the segments 44, by the engagement be- tween the tapering outer walls 48 and the inner walls of the frustoconical channel restriction 18, exert a radial clamping force on the pole base end 25, anchoring it securely within the channel 12. In the event that the pole 24 is hit by a vehicle, the high clamping force on the pole base end 25 from the segments 44 ensures that the pole lower part 23 remains surely anchored in the precast element 8 during the course of the collision. Additionally, as the transverse force from the collision is transferred to the segments 44 of the second retaining element 6, the friction between the outer walls 48 of the segments 44 and the inner walls of the frustoconical channel restriction 18 increase. This may further increase the effectiveness of the second retaining element 6 in preventing the pole lower part 23 from being drawn out of the precast element 8. Further, it is contemplated that the engagement between the pole base end 25 and the second retaining element 6, and between the second retaining element 6 and the inner walls of the frustoconical channel restriction 18, may, on one hand be made sufficiently strong to prevent the pole 24 from being drawn out of the precast element 8 during a collision involving transverse forces acting on the pole 24, while on the other hand be sufficiently weak to allow easy removal and installation of the pole 24 in normal condi- tions where the transverse forces acting on the pole 24 are negligible.

Fig. 9 shows a cross section of a octagonal pole 24 comprising straight pole wall sections, one of which is designated the reference numeral 54, and curved pole wall sections, one of which is designated the reference numeral 54'. To render the pole yielda- ble but still able to support normal loads, reinforcement rods, one of which is designated the reference numeral 56, extending along the axis of the pole 24, correspond to reinforcement rod channels, one of which is designated the reference numeral 58, in the inner walls, The reinforcement rods stiffen the pole 24 because the thin pole wall sections 54 and 54' do not in themselves convey the rigidity necessary to support normal loads. In the event of a vehicle hitting the pole 24, the resulting deformation of the cross section of the pole 24 at the point of impact deforms the reinforcement rod channels 58, thereby annulling the stiffening effect conveyed to the pole 24 by the reinforcement rods 56. Then the pole 24 may be controllably deformed and safely dissipate the kinetic energy of the vehicle. The pole 24 is preferably constructed from a metal such as aluminum, steel, alloys etc., or plastics such as fiber reinforced plastic. The pole 24 having reinforcement rod channels 58 in the inner walls may be produced as a single piece through extrusion, but the reinforcement rod channels may also be produced separately and then fastened to the inner walls of the pole 24. Although an octagonal yieldable pole 24 is shown in Fig. 9, other cross sections, and other kinds of poles, yieldable or non-yieldable, may be used with the anchoring assembly of the present invention.

Fig. 10 shows the mounting of a sign 26 onto the pole 24 by means of two pole brackets, one of which is designated the reference numeral 60, and to the pole brackets 60 connected sign rail clamps, one of which is designated the reference numeral 62, said sign rail clamps engaging sign rails, one of which is designated the reference numeral 64, by the action of nut and bolt 66. List of parts with reference to the figures