EP1921210B1

EP1921210B1 - Avalanche and the like protection element

Info

Publication number: EP1921210B1
Application number: EP20060425767
Authority: EP
Inventors: Vittorino Betti; Christian Gartner; Dimitri Canepari
Original assignee: Betonform SRL
Current assignee: Betonform SRL
Priority date: 2006-11-10
Filing date: 2006-11-10
Publication date: 2015-05-13
Anticipated expiration: 2026-11-10
Also published as: PL1921210T3; SI1921210T1; PT1921210E; EP1921210A1; ES2544947T3; EP1921210A8

Description

The present invention refers to an avalanche protection element and the like.
It is known the use of avalanche protection elements that work by holding snow on mountain slopes in order to prevent avalanche formation.
Such elements are generally formed by a wire net surface that is arranged substantially perpendicular, or otherwise tilted, to the ground and fastened thereto so as to block or at least contain snow advancing.
Thus, by arranging several rows of such elements along mountain slopes, snow advancing can be confined, thereby preventing formation of avalanches or anyhow remarkably reducing their mass.
Several typologies of structures have been developed in order to most suitably arrange said net surfaces and, generally, to allow an easy fastening thereof to the mountain ground.
In general, such structures should meet the need to be resistant to stresses caused by the weight of the snow, concomitantly keeping costs reasonable.
A viable implemented solution consists in the use of a pyramid-shaped structure, in which the net surface defining its base is connected to the ground at the pyramid vertex by a strut developing along the height of said geometric figure.
Moreover, the vertex is connected to the corners of the net surface by wire cables functioning as tensile-stressed connection elements.
An example of said structures is described in European Pat. N° EP 828 897 , in which it is described an umbrella-shaped avalanche protection element requiring a single anchoring point. Such an avalanche protection element is formed by a strut with the upslope end directly or indirectly anchored to the ground, whereas the downslope end is provided with a support onto which there are applied, lying on a single plane perpendicular with respect to the longitudinal axis of said strut, four beams arranged in an X shape and radially developing, converging toward said support. At the center of the X, the beams are hinged to the downslope end of the strut, whereas the opposite points thereof are connected by strands to the upslope end of the same strut; moreover, the same beams are connected thereamong with a cable.
However, this structure and others implemented to date do not face a relevant problem mainly linked to the climate conditions under which said avalanche protection elements are used, and to their operation steps.
In fact, known elements have connections between the beams and the other components, made with bolted junctions, in which it is necessary to provide a certain multidirectional play in order to allow an optimal tension distribution when the snow-generated load is applied.
In particular, these junctions are used between the tensile-stressed-connection-element-forming rods and the beams on which the net surface is supported, in a manner such that, thanks to the existing play, the former may act as hinges; such a constructive solution prevent a snow load from transmitting momenta to said beams.
However, during use of the avalanche protection elements such bolted junctions are easily covered with snow, or anyhow with layers of ice; this event undoes or anyhow restricts the play usually provided by such connections.
As a consequence, the junction does not act as a mere hinge anymore, and the momentum is at least partially transmitted by the junction, giving rise to stresses frequently causing breaks in the structure.
As it is not possible to assess the degree of said additional stresses, the sole solution adopted to date lies in a structure oversizing that however, due to practical and economical reasons, cannot be too high and therefore ensures no complete prevention of such breaks.
Hence, the technical problem underlying the present invention is to provide an avalanche protection element overcoming the drawbacks hereto-mentioned with reference to the known art.
Such a problem is solved by an avalanche protection element according to claim 1.
The present invention provides several relevant advantages. The main advantage lies in that it prevents breaks linked to snow accumulations or ice layers, requiring no oversizing in the component parts of the structure.
Other advantages, features and the operation modes of the present invention will be made evident from the following detailed description of some embodiments thereof, given by way of example and not for limiting purposes. Reference will be made to the figures of the annexed drawings, wherein:

Figure 1 is a sketch illustrating according to a perspective view an avalanche protection element according to the present invention;
Figure 2 is a plan view of the avalanche protection element according to a first embodiment thereof;
Figures 3A to 3C are, respectively, a partial front view along a section A-A, a partial side view along a section B-B, and a section of beams with respective plates as coupling elements, details of the avalanche protection element of Figure 2;
Figures 4A and 4B are a front view and a side view, respectively, of a beam, detail of Figure 3C;
Figure 5 shows a front view of the avalanche protection element of Figure 2;
Figure 6 is a plan view of the avalanche protection element according to a second embodiment thereof;
Figures 7A to 7D are respectively a partial front view along a section A-A, a partial plan view, a partial side view along section B-B, and a section of a beam and of a respective coupling element, details of the avalanche protection element of Figure 6; and
Figure 8 shows a front view of the avalanche protection element of Figure 6.

Referring initially to Figure 1, an avalanche protection element preferably has a substantially octahedron-like shape, and during use it is arranged in a manner such as to be fastened to the ground of a mountain slope, at an end 32 thereof, according to modes that will be detailed hereinafter.
Then, the avalanche protection element is laid onto the ground, so as to have a protection surface 1 remaining arranged substantially perpendicularly to the ground, or otherwise tilted.
Incidentally, note that the surface 1 matches the base of the two facing pyramids forming said octahedron.
The surface 1 can thus hold snow, preventing the formation of avalanches or anyhow confining their advancing, analogously to known avalanche protection elements.
For this purpose, the surface 1 is made of a metal mesh net, allowing to contain snow depositing on a mountain slope.
Therefore, to obtain adequate protection a plurality of avalanche protection elements are used, combined according to different geometric schemes in a manner such as to form variously patterned barriers.
E.g., the avalanche protection elements may be positioned side by side the one to the other, so as to create a continuous barrier, or spaced thereamong, thereby leaving a transit option to wild animals.
The selection of the most suitable geometric scheme is linked to the sizing of the avalanche protection barrier and the possible presence of animals in the area.
The avalanche protection element preferably comprises at least two beams 2 supporting the protection surface 1.
Moreover, the beams 2 are connected to a stem 3 at a first portion 31 by suitable connecting means 4, illustrated, according to a first embodiment, in Figure 2.
In addition, always referring to Figure 1, the beams 2 are connected to the stem 3 at the end 32.
Furthermore, the avalanche protection element has a rod 6 developing, with respect to the surface 1, in a direction opposite to that of the stem 3.
Therefore, the rod 6 supports second tensile-stressed connection elements 7, them also arranged in a position opposite to the first tensile-stressed connection elements 5, with respect to the protection surface 1.
Advantageously, as it will be made evident hereinafter, the presence of the second tensile-stressed connection elements 7 connected to the beams 2 prevents those breaking phenomena occurring following the formation of snow accumulations or ice sheets and the momentum consequently acting on the beams 2.
In fact, the second tensile-stressed connection elements, owing to the load produced by the action of snow, act with their own pull and oppose the momentum generated by the presence of snow accumulations or ice sheets on the first tensile-stressed connection elements at the points of connection with the beams.
Moreover, evidently such a solution can prove particularly advantageous also for other alike applications, such as landslide protection, in which similar structures can analogously allow to oppose the momenta generated onto beams.
Preferably, the first and second tensile-stressed connection elements are made by wire cables and fastened to the beams 2 by respective plates 25 and 27.
Therefore, referring to Figure 2, the stem 3 is connected to ground-fastening means 8 at the end 32, to which there are further fastened the first tensile-stressed connection elements 5.
In particular, said ground-fastening means 8 comprises a cable 81 apt to be immersed in the ground and keep the avalanche protection element in a selected position.
Said ground-fastening means 8 may be made with steps known to a person skilled in the art, and therefore will not be detailed hereinafter.
Moreover, to better position the avalanche protection element according to the present invention there are resting feet 11, connected to the beams 2 at respective ends 21.
Referring again to Figure 1 and to Figure 5, preferably the protection surface 1 has a substantially quadrangular shape and the beams 2 are arranged along diagonals thereof.
Thus, it is allowed an effective resting onto the ground, simply made by the ends 21 of the beams. Moreover, such an arrangement proves particularly advantageous in the tension distribution on the beams 2.
Accordingly, stem 3 and rod 6 are connected to the protection surface 1 substantially at a center point of the latter, point defined by the intersection of the diagonals of the surface itself.
According to a preferred embodiment, the connecting means 4 is arranged substantially at the intersection of the diagonals of the protection surface 1. Note also that, as it will be illustrated hereinafter, in the present embodiment said point matches that of intersection of the beams 2.
In such a configuration the beams 2 have a radial development with respect to stem 3 and rod 6, as illustrated in Figure 1.
Following this arrangement of the beams 2, stem 3 and rod 6 are substantially aligned and develop substantially perpendicular to the protection surface 1, in a manner such that stem and rod match each with a respective height of the pyramids forming the octahedron.
Referring to Figures 3A to 3C, illustrating a first embodiment of the avalanche protection element according to the present invention, the rod 6 is connected to the beams 2 by a joint 24 obtained on a locking plate 23.
In the present embodiment, the beams are present in a number equal to two, intersected therebetween substantially at the center of the protection surface 1. In particular, the rod 6 is therefore connected to the beams 2 at an intersection point thereof, as illustrated in Figure 3A.
In order to obtain a joint between the two beams, they have respective connecting sections 26, which, once coupled, allow to arrange the beams inside of a same plane, in a substantially X-like configuration. Such a configuration provides high rigidity to the structure and optimally supports the protection surface.
To ensure a stable connection between the two beams a second locking plate 22 is used, connectible to the plate 23 by bolts, in a manner such as to interpose between the pair of plates 22 and 23 the beams 2, which thereby remain locked therebetween.
Therefore, referring to Figure 3B, the connection between rod 6 and beams 2 that, as illustrated in the foregoing takes place by the joint 24, is pivotable, in a manner such as to allow to the rod rotary motions inside of a substantially vertical plane.
Such a connection may be made, e.g., by a pin 63, located at an end 61 of the rod 6.
Moreover, the same pivotable connection may be provided also at the connection between stem 3 and beams 2. In this case, as illustrated in Figure 2, such a motion occurs about a horizontal axis, substantially perpendicular to the stem 3 itself. Evidently, the horizontal direction is defined by the ground-resting position of the avalanche protection element.
To allow such a motion, the connecting means 4 comprises a substantially spherical element 41, fastened to the plate 23 by welding, and a nut 42 apt to house the spherical element 41.
Said elements are then kept connected by means of a latch 43 allowing said pivotable connection between the spherical element 41 and the nut 42.
Advantageously, this type of connection allows an improved distribution of stresses in the structure when the latter is subjected to a snow load.
In fact, it has to be understood that snow-generated load is not constant along the vertical direction, the structure being generally subjected to greater stresses in the bottom portion thereof, where the avalanche has greater strength.
Moreover, advantageously such a connection may also work as a ball joint, allowing a certain movability in all directions, providing a certain play in the connection between latch and related seat on the spherical element.
Note anyhow that the option of rotation (pivoting) about axis a is inhibited by the concomitant presence of the first and second tensile-stressed connection elements, keeping the beams 2 in a substantially stable position with the protection surface.
Moreover, this type of connection proves advantageous with respect to the connections made according to the known art, as it requires no bolted connection in which a limited play is provided, therefore allowing a simple and effective manufacturing of the avalanche protection element, as well as preventing also in this connection the problems related to the aforementioned momenta.
Moreover, evidently the second tensile-stressed connection elements, due to their location, are stressed oppositely with respect to the first tensile-stressed connection elements and, therefore, in case of formation of ice sheets or the like will produce a momentum that will tend to oppose that generated by the first tensile-stressed connection elements.
In particular, in this embodiment, the second tensile-stressed connection elements 7 are present in a number equal to two and intersected at an end 64 of the rod 6. This option is linked to the use of the pivotable connection of the rod 6 and, thus, it is avoided the presence of additional connections between the rod itself and the second tensile-stressed connection elements.
It will be understood that the present invention is susceptible of several embodiments alternative to the hereto-described one, some of which will be briefly illustrated hereinafter with reference to the sole aspects differentiating them from the first embodiment considered hereto.
Referring to Figure 6, an avalanche protection element according to a second embodiment has a rod 36 integrally connected to the stem 3.
In other words, rod 36 and stem 3 form a single body of elongated shape, wherein the rod 36 is made as an extension of the stem 3 beyond the connecting means 4.
In fact, referring to figures 7A to 7D, in the present embodiment in particular the connecting means 4 is apt to make a slidable connection between the beams 2 and the stem 3 or, more precisely, the single piece formed by stem 3 and rod 36.
Such a connection is made by a seat 41, of a shape complementary to the stem 3, which may receive therein the stem 3 itself and the rod 36, allowing a certain sliding.
The beams 2 are arranged radially with respect to the stem, analogously to the preceding embodiment, and are housed in suitable coupling sections 42, inside which the former are locked in a manner such as to obtain an X-like arrangement, again analogously to the preceding case.
According to a preferred embodiment, the coupling sections are made by means of seats apt to house the beams 2, as illustrated in Figure 7D.
Moreover, note that in this case, due to obvious constructive reasons, each of the beams 2 extends along half of the diagonal of the protection surface, and that, in case of a quadrangular-shaped surface, there will be four beams radially arranged with respect to the stem 3.
The connection between each of the beams 2 is made by the connecting means 4, which provides sufficient rigidity to the structure thus made.
Analogously to the preceding embodiment, the option of motion between stem and beams, though differently implemented here, allows an optimal distribution of snow load-generated stresses. Moreover, bolted junctions are again avoided also at the connection between stem and beams.
Hence, referring to Figure 7C, the second tensile-stressed connection elements 7 are instead connected to a plate 37, placed at an end of said rod 36, in a manner such as to at least partially prevent, together with the first tensile-stressed connection elements 5, sliding motions of the connecting means with respect to the stem and the rod 36.
Moreover, the avalanche protection element according to the present embodiment further has means apt to limit sliding motions of said connecting means 4, which, e.g., may be made by gudgeons 44 respectively inserted in the stem and in the rod 36 and fastened by split pins.
The present invention has hereto been described with reference to preferred embodiments thereof. It is understood that there might be other embodiments referable to the same inventive kernel, all falling within the protective scope of the claims hereinafter.

Claims

An avalanche and the like protection element comprising a protection surface (1), beams (2) supporting said protection surface (1), a stem (3) developing in a direction with respect to said protection surface (1), and first tensile-stressed connection elements (5), said beams (2) being connected to a first portion (31) of said stem (3) by connecting means (4) and being further connected to an end (32) of said stem (3) by said first tensile-stressed connection elements (5),
characterised in that it further comprises a rod (6; 36) developing in an opposite direction to the developing direction of said stem (3) with respect to said protection surface (1), and second tensile-stressed connection elements (7) connected to said beams (2), said rod (6; 36) supporting said second tensile-stressed connection elements (7).
The avalanche and the like protection element according to claim 1, wherein said stem (3) and said rod (6; 36) are connected to said protection surface (1) substantially at a central point thereof.
The avalanche and the like protection element according to claim 1 or 2, wherein said first and second tensile-stressed connection elements (5, 7) are made by wire cables.
The avalanche and the like protection element according to one of the preceding claims, wherein said beams (2) extend radially with respect to said stem (3) and/or said rod (6; 36).
The avalanche and the like protection element according to one of the preceding claims, wherein said stem (3) and/or said rod (6; 36) develop substantially perpendicular to said protection surface (1).
The avalanche and the like protection element according to one of the preceding claims, wherein said rod (6; 36) and said stem (3) are substantially aligned therebetween.
The avalanche and the like protection element according to one of the preceding claims, wherein said rod (6) is connected to said beams (2).
The avalanche and the like protection element according to the preceding claim, wherein said beams (2) are present in a number at least equal to two and being intersected therebetween, in a manner such that said rod (6; 36) be connected to said beams (2) at an intersection point thereof.
The avalanche and the like protection element according to the preceding claim, wherein said at least two beams (2) have a connecting section, apt to make a joint connection between said beams (2).
The avalanche and the like protection element according to one of the claims 7 to 9, wherein said rod (6) is pivotally connected to said beams (2), in a manner such as to make motions inside of a substantially vertical plane.
The avalanche and the like protection element according to the preceding claim, wherein said rod (6) is connected to said beams (2), at an end (61) thereof, by a pin (63).
The avalanche and the like protection element according to the preceding claim, wherein said connecting means (4) between said stem (3) and said beams (2) is apt to make a connection pivotable along an axis (a) substantially horizontal and substantially perpendicular to said stem (3).
The avalanche and the like protection element according to the preceding claim, wherein said connecting means (4) comprises a substantially spherical element (41) and a nut (42) apt to house said spherical element (41) and a latch (43) apt to allow a pivotable connection between said spherical element (41) and said nut (42).
The avalanche and the like protection element according to claims 12 and 13, wherein said spherical element (41) is connected to said beams (2) and said nut (42) is connected to said stem (3).
The avalanche and the like protection element according to one of the claims 7 to 14, comprising a pair of locking plates (22, 23) apt to make a stable connection between said at least two beams (2).
The avalanche and the like protection element according to claim 15 and one of the claims 13 or 14, wherein said spherical element (41) is connected by welding to a first plate (22) of said pair (22, 23).
The avalanche and the like protection element according to claim 15 or 16, wherein a second plate (23) of said pair (22, 23), comprises a joint (24) apt to make a connection with said rod (6).
The avalanche and the like protection element according to one of the claims 1 to 6, wherein said rod (36) is integrally connected to said stem (3).
The avalanche and the like protection element according to the preceding claim, wherein said connecting means (4) is apt to make a slidable connection between said beams (2) and said stem (3).
The avalanche and the like protection element according to claim 18 or 19, wherein said connecting means (4) comprises a seat (41) apt to receive said stem (3) and said rod (36) and a plurality of coupling sections (42) apt to house said beams (2).
The avalanche and the like protection element according to claim 19 or 20, wherein said second tensile-stressed connection elements (7) are fastened to a plate (37), connected to said rod (36), in a manner such as to at least partially prevent sliding motions of said connecting means with respect to said stem (3) and/or said rod (36).
The avalanche and the like protection element according to one of the claims 19 to 21, wherein said stem (3) and/or said rod (36) comprise means (44) apt to restrict sliding motions of said connecting means (4).
The avalanche and the like protection element according to the preceding claim, wherein said means (44) apt to restrict sliding motions are made by gudgeons (44) inserted in said stem (3) and said rod (36), respectively.
The avalanche and the like protection element according to one of the claims 18 to 23, wherein said beams (2) extend substantially radially to said connecting means (4).
The avalanche and the like protection element according to one of the preceding claims, wherein said protection surface (1) has a quadrangular shape and said beams (2) are arranged substantially along diagonals of said protection surface (1).
The avalanche and the like protection element according to the preceding claim, wherein said connecting means (4) is arranged substantially at the intersection of the diagonals of said protection surface (1).
The avalanche and the like protection element according to claim 2 and one of the claims 25 or 26, wherein said central point of connection matches the intersection of the diagonals of said protection surface (1).
The avalanche and the like protection element according to one of the preceding claims, wherein said protection surface (1) is apt to be arranged substantially perpendicular to the ground.