Building element for supporting grid walls with a bulk material filling

Abstract: In the technical field of supporting grid walls with a bulk material filling there is a substantial need of building elements of improved bearing capacity in relation to the construction mass as well as of good securing capacity for the bulk material filling. The solution according to the invention indicates a building element construction comprising longitudinal beams with profile legs (PS1, PS2), the first of which forms a bearing surface (F1) and the second a retaining surface (F2) for the bulk material filling. The first profile leg (PS1) has a wedge-shaped, particularly trapezoidal, cross-section. The cross-sectional height (H1) thereof increases from the out­ side inwards.

Description: The invention relates to a building element according to the preamble of the claim 1, in particular of the claim 8. In the particular case there are frame-shaped building elements comprising at least two beams which are arranged at an angle to one another and connected in a form-locking or material-locking manner. Accordingly such beams there can be regarded as sub-elements. Especially in the case of such sub-elements being connected in a form-locking manner the whole building element may be regarded also as a kit consisting of sub-elements, from which a complete building element can be assembled, particularly in situ. Accordingly the term "building element" is intended to comprise unitary elements as well as multi-part and more complex elements. Typical applications for grid structures with bulk material filling are slope supporting as well as stand-alone noise protection walls, preferably with front faces having gaps or windows, wherein filling material is exposed so as to carry vegetation. Frame-shaped building elements according to the species defined in the preamble of the above-mentioned claim 8 for the construction of grid walls with bulk material filling are known in the art from the DE-A-2 937 478. Those building elements comprise one or more longitudinal beams with two profile legs arranged under an angle to each other. A first profile leg extending substantially parallel to the frame plane has a plain bulk material bearing surface on its uper side and a plain base surface on its bottom side. Both surfaces extend in parallel, and accordingly the cross-sectional height of the profile leg is constant. As a consequence thereof the stability of said first profile leg against bending moments exerted by forces acting in a vertical plane extending along the free longitudinal edge of the profile leg has its minimum in this edge region, which is highly exposed to vertical forces due to the weight of the bulk material and the usually inevitable process of compacting the bulk material after filling-in thereof. Accordingly, there is a demand to amend this structure in view of the ratio of the bending stability to the concrete mass and the dimensions of the armature mass, i.e. the overall fabrication expenses. Moreover, the cross-sectional height of said first profile leg at its free longitudinal edge, which faces the bulk material located in the internal space of the frame, is comparatively small. This means a comparatively poor supporting effect of the profile against the bulk material within the frame. The EP-A-0 039 448 discloses building elements for grid walls formed as comparatively short profile elements with two profile legs arranged at an angle to one another. An upper first profile leg, the cross-section of which extends horizontally, has a bulk material bearing surface on its upper side, while a second profile leg joined to the inner longitudinal edge of the first profile leg extends vertically downward from said first leg. Indeed, the inner edge of the upper profile leg, due to the joined second leg, shows great vertical bending stability against moments acting in a plane parallel to the second leg. However, this is of no use since each profile element is nested in a window of a bearing front plate of the wall in such a manner that the lower edge of said window is in supporting contact with the whole length of the bottom side of the first profile leg. Substantially no bending moments acting parallel to the second profile leg can occur accordingly. On the other side, considerable bending moments acting in a cross-sectional plane of the profile element may occur due to bulk material escaping through the free window opening located above each profile element and forming an exposed slope. Those bending moments exert their maximum action on the profile element in the region of the supporting window edge, where the bending stability of the profile element is rduced by an abrupt contour recess at the bottom side of the first profile leg. Summarizing, this structure fails to show a real profile beam support function. A further grid wall building element shown in the DE-A-3 106 486 is frame-shaped and comprises longitudinal profile beams with a bulk material bearing surface oriented upward and forming a free outer longitudinal edge of comparatively small cross-sectional height. The profile also comprises a bulk material supporting surface of considerable height and oriented towards the inner space of the frame. However, the bulk-bearing capacity of this structure is comparatively poor because there is no surface active in retaining the bulk material which rests on the bearing surface from sliding outward, from being washed out by rain or blown out by wind. Accordingly the utilization of the comparatively heavy portion in the region of the inner longitudinal edge of the beam is low, since this portion is overdimensioned. The grid wall shown in the FR-A-2 488 302 comprises longitudinal beams of a Z-shaped cross-section. Those beams have a central profile section of constant cross-sectional height forming a bulk material bearing surface and profile legs joined at an angle to both sides of said central profile section. This structure in principle allows to secure considerable bulk material mass on the bearing surface and to realize sufficient bending stablity in both longitudinal edge regions of the central profile section. However, with a view on the cross-section the longitudinal beam is vertically supported in the center of said constant-height profile section by gibbet-like end-sections of transversal beams. This means that a considerable portion of the cross-sectional width of the longitudinal beam is stressed like a cantilever plate loaded by bulk material. This entails bending moments acting in cross-sectional planes with maxima in the middle portion of the cross-sectional width of said constant-height profile section, which generally is not in accordance with an optimum utilization of the concrete mass and armature. In view of the cited art it is the task of the present invention to create building elements of the above-mentioned species which allow improvements with regard to the combination of their carrying capacity and their bond strength in relation to mass and construction cost, as well as with regard to their retaining and securing ability with respect to the bulk material filling. This task is accomplished by structures according to the features of claim 1, 2 or 8 respectively. Essential for accomplishing the task by the features of claim 1 for a beam-shaped building element is the overall enhancement of the bending stability of the cross-section due to a relative concentration of cross-sectional areas in outer regions of the cross-section. Moreover, the bending stability is specifically enhanced in the cross-sectional region near the free longitudinal edge of the wedge-like first profile leg. Nevertheless, the bending stability of the longitudinal, vertical section of the beam in the central region of the width of the first profile leg is still comparatively great, since the cross-sectional height increases evenly over the width of the first profile leg and, accordingly, has already a considerable magnitude in this critical region. All this is combined with excellent holding capacity for bulk material on the bearing surface of the first profile leg due to the second profile leg joined to the outer outer longitudinal limit of the first profile leg so as to secure such bulk material in horizontal direction. As defined in the solution according to claim 2 the cross-section of the second profile leg can also be of wedge-like design. This contributes to enhancing the bending stability in relation to the overall cross-sectional area. Moreover, in certain cases where the horizontal forces acting on the second profile leg exceed the vertical forces acting on the first profile leg it may be advisable to give a wedge-like design to the second profile leg not additionally to such design of the first profile leg but instead of the latter. The design of the first profile leg according to claim 3 with a bulk material supporting surface at its longitudinal edge positioned opposite the second profile leg brings the advantage of enhanced horizontal securing action on the bulk material against compacting pressure. Such supporting surface can be made comparatively broad due to the wedge-like shape of the first profile leg. As far as the mainly horizontal force transmission on the bulk material is concerned the effect of the supporting surface may be regarded as analogous to the one of the aforementioned retaining surface at the second profile leg. Retaining and supporting surfaces, therefore, may be in common named "holding surfaces". The features of claims 4 to 7 specify advantageous embodiments with regard to the angle between the supporting and the bearing surface and with regard to the relatin between the width of the bearing surface and the supporting surface. The solution according to claim 8 is analogous to the one according to claim 1 in all essential features, but adequately specified for a frame-shaped building element, which comprises a beam-shaped element according to claim 1. In this sense the definition of embodiments according to claims 9 to 13 is analogous to the one of the embodiments according to claims 3 to 7. In connection with a frame-shaped building element the outwardly slanted arrangement of a bearing surface according to claim 14 may contribute to enhancing the width of the adjacent supporting surface. The features of claim 15 are to specify a variation of shaping the second profile leg of a longitudinal beam within a frame-shaped building element, thus far analogous to the essential features of claim 3. The features according to claims 16 and 17 define embodiments showing enhanced resistance of the free longitudinal edges, above all the upper longitudinal edge, at the front face of a second profile leg. The directive of claim 18 for slanting a bearing surface allows optimizing the bulk material filling-in and compacting work. Specific embodiments of the invention will now be described with reference to the accompanying drawings. Herein represents: Fig.1 an overall vertical cross-section of a grid wall with frame-shaped building elements and a bulk material filling, Fig.1A a partial view in horizontal direction of a second embodiment of a grid structure showing a longitudinal beam in its end view and the connection part of a corresponding cross beam, Fig.1B a longitudinal view of a beam-shaped building element for a third embodiment of a grid structure and Fig.1C a partial cross-section of a longitudinal beam with a portion of a connected cross beam of a frame shaped building element similar to those in the grid structure according to Fig.1. The supporting grid wall according to Fig.1 serves as a slope retaining wall and consists of a frame-shaped building elements placed on top one another. Each consists of two front and rear longitudinal beams L1 and at least one cross beam Q. The longitudinal and cross beams are arranged in the usual manner at an angle to one another, preferably a right angle, and are made, for example, in one piece from concrete. A subsequent material-locking or form-locking connection between the longitudinal and and cross beams, eg. by means of teethed elements of the known type, or by bolting together and/or other clamping means may, in principle, also be considered. Important according to overall characteristics of claim 1 is the construction of the longitudinal beams with profile legs PS1 and PS2, the first of which forms a bearing surface F1 and the second a retaining surface F2 for the bulk material filling, PS1 having a wedge-shaped, in this case trapezoidal, cross-section with a cross-sectional height H1 which increases from the outside inwards. This cross-section can, in the manner indicated in Fig.1C, be provided with reinforcing AR1 - AR3 in positions which ensure an optimum increase in strength. On the whole, compared to the known building elements, an improved bearing capacity is obtained in relation to the mass, as well as good securing of the bulk material filling and at the same time root space is provided for the usual vegetation of the bulk material slopes exposed at the front of the wall. Generally the bearing surfaces have a slant adapted to the angle of slope of the bulk material filling in relation to the wall plane E1 and the frame plane E2, in which connection a possible inclination of the former with respect to the vertical must be taken into account, whereas the holding surfaces are arranged more steeply and serve essentially to secure the position of the bulk material filling in the horizontal direction. The latter also applies to the supporting surfaces F1b formed on the inside of the profile legs PS2, which assist uniform compaction of the filling. Preferred values for the angle arrangement between the bearing surface, supporting surface and the bottom base surface F1a can be noted from the characterising part of claims 2 to 8 as well as 14 to 18. According to claim 24 and the associated dependent claims, it is also possible to use the longitudinal beams L1 as separate building elements for installation with cross beams in the supporting grid. The embodiment according to Pig. 1A is characterised by the outwardly declining slant of the bearing surface FA1. For the last mentioned mode of installation of the longitudinal beams L1A, this provides the advantage that their position can be secured against outward shifting under the effect of the filling pressure by means of corresponding recesses in the cross beam O1A resting thereon. The longitudinal beam L1B according to Fig. 1B is characterised by a greater horizontal bending strength of the profile leg PS2B due to the fact that its cross-sectional width B1 increases towards the top at a comparatively small cross-sectional area. The bearing surface F1 on the profile leg PS1B may, as indicated by dot-dash lines, also be made without a slant and the profile leg itself may have the same thickness all over. Fig. 1C shows the particularly advantageous embodiment of the free longitudinal edge LK1 according to claims 10 and 11, which helps to avoid damages to the sensitive edge region under rough conditions of use.

Claims: A building element for supporting grid walls with a bulk material filling, designed as a profile beam (L1) with at least two profile legs (PS1, PS2) arranged at an angle to one another, wherein a first one (PS1) of said profile legs has at least one bearing surface (F1) for the bulk material, and wherein a second one (PS2) of said profile legs has at least one retaining surface (F2) for the bulk material, said retaining surface being arranged at an angle to said bearing surface so as to secure the bulk material on the bearing surface essentially in the horizontal direction, characterized in that said first profile leg (PS1) has a wedge-like cross-section with a a cross-sectional height which increases evenly from the point where it is joined to said second profile leg (PS2). A building element for supporting grid walls with a bulk material filling, designed as a profile beam (L1B) with at least two profile legs (PS1B, PS2B) arranged at an angle to one another, wherein a first one (PS1B) of said profile legs has at least one bearing surface (FB1) for the bulk material, and wherein a second one (PS2B) of said profile legs has at least one retaining surface (FB2) for the bulk material, said retaining surface being arranged at an angle to said bearing surface so as to secure the bulk material on the bearing surface essentially in the horizontal direction, in particular a building element according to claim 1, characterized in that said second profile leg (PS2B) has a wedge-like cross-section with a cross-sectional width (B1) which increases from the point where it is joined to said first profile leg (PS1B). A building element according to claim 1, characterized in that the first profile leg (PS1), at its longitudinal edge positioned opposite the second profile leg (PS2) forms a supporting surface (F1b) for the bulk material, said supporting surface being arranged at an angle with respect to said bearing surface so as to secure the position of the bulk material essentially in the horizontal direction. A building element according to claim 3, characterized in that the angle between said bearing surface (F1) and said supporting surface (F1a) is less than 90°. A building element according to claim 4, characterized in that the angle between said bearing surface (F1) and said supporting surface (F1a) is less than ⁸5°. A building element according to anyone of claims 3 to 5, characterized in that the width of said supporting surface (F1b) amounts to at least 35% of the width of said bearing surface (F1). A building element according to claim 6, characterized in that the width of said supporting surface (F1b) amounts to at least 50% of the width of said bearing surface (F1). A frame-shaped building element for supporting grid walls with a bulk material filling, comprising at least two beams (L, Q) arranged at an angle to one another and connected in a form-locking or material-locking manner, at least one (L) of said profile beams being constructed as a longitudinal beam extending Substantially parallel to the wall plane (E1) and comprising at least two profile legs (PS1, PS2) arranged at an angle to one another, wherein a first one (PS1) of said profile legs forms a bearing surface (F1) for the bulk material covering substantially the central part of the longitudinal beam (L), and wherein a second one (PS2) of said profile legs forms a retaining surface (F2) for the bulk material, said retaining surface being arranged facing the inside space of the frame, offset to the outside of the frame with respect to said bearing surface and at an angle thereto so as to secure the bulk material on the bearing surface essentially in the horizontal direction, characterized in that said first profile leg (PS1) has a wedge-like cross-section with a cross-sectional height which increases evenly from the point inwards where the first profile leg is joined to the second profile leg (PS2). A building element according to claim 8, characterized in that the underside of the first profile leg (PS1) forms an at least approximately plane base surface (F1a) which, with respect to the frame plane (E2) slants downward in direction toward the inside space of the frame, and on its side facing the inside space of the frame forms at least one supporting surface (F1b) for the bulk material filling, said supporting surface being arranged at an angle to the bearing surface (F1) and the base surface (F1a) so as to secure the neighbouring bulk material essentially in the horizontal direction. A building element according to claim 9, characterized in that the angle between the base surface (F1a) and the supporting surface (F1b) is less than 90°. A building element according to claim 10, characterized in that the angle between the base surface (F1a) and the supporting surface (F1b) is less than about 80°. A building element according to anyone of claims 9 to 11, characterized in that the width of the supporting surface (F1b) is at least about 30% of the width of the base surface (F1a). A building element according to claim 12, characterized in that the width of the supporting surface (F1b) is at least about 45% of the width of the base surface (F1a). A building element according to claim anyone of claims 8 to 13, characterized in that the bearing surface (F1) of the first profile leg (PS1) is arranged, with respect to the frame plane (E2), slanting downward in direction from the inside space of the frame outward. A building element according to anyone of claims 8 to 14, characterized in that the second profile leg has a cross-sectional width which, over at least part of its cross-sectional height, increases from the first profile leg upward. A building element according to claim 8, characterized in that the front side of the second profile leg (PS2) has at least two surface sections (F2a, F2b) arranged tilted in relation to one another around the longitudinal axis of the profile beam so as to form an outward projecting, obtuse-angled longitudinal edge. A building element according to claim 16, characterized in that the front side of the second profile leg (PS2) has a first surface section (F2a) which, with respect to the wall plane (E1), slants upward and outward, and is followed by a second surface section (F2b) which extends upward into the region of the top longitudinal end edge and which, with respect to said first surface section, is arranged tilted around the longitudinal axis of the beam in direction of the inside space of the frame-like structure. A Building element according to claim 8, characterized in that the bearing surface for the bulk material is arranged, with respect to the wall plane, slanted at an angle which at the most corresponds to about the angle of slope of the filling material, possibly increased or reduced by the angle of slant of the wall.

Inventors: JAECKLIN FELIX P, JAECKLIN, FELIX PAUL, DR.
Applicants: GEOTECH LIZENZ AG, GEOTECH-LIZENZ AG
Application year: 1985
Main classification: E02D29
IPC codes: E02D29