Methods for securing underground cavities against intrusion and collapse

Abstract

In order to ensure that a method for securing underground cavities against break-ins and collapses using artificial mineral fibers is technically inexpensive, economically viable and can be implemented safely, it is proposed to compress the artificial mineral fibers into bales (2), to tightly wrap the artificial mineral fibers compressed into bales (2) with film (3), to apply a layer (7) of bales (2) wrapped with film (3) to a base (4) of an underground cavity (1), to apply a covering layer (8) to the layer (7) of bales (2) wrapped with film (3), and to alternately apply further layers (9, 12, 14) of bales (2) wrapped with film (3) and further covering layers (10, 13) until a ceiling or ridge region (15) of the underground cavity (1) is reached.

Description

[0001] The invention relates to a method for securing underground cavities against intrusion and collapse using artificial mineral fibers (AMF).

[0002] There is currently no viable recycling method for artificial mineral fibers. Handling and disposing of such fibers is complicated and economically expensive. Furthermore, landfilling is becoming increasingly complex, while the available land area is dwindling. Consequently, it has been proposed to use such artificial mineral fibers in bound form, for example, as aggregate in concrete. However, this requires an unnecessary process of breaking down the fibers, leading to increased air pollution and thus a health hazard from the released fibers. It also generates additional filter waste. Personnel working in such facilities are exposed to a comparatively high level of risk.

[0003] The invention is based on the objective of providing a method for securing underground cavities against collapses and break-ins using artificial mineral fibers, in which the aforementioned disadvantages occur to a far lesser extent - if at all - and by means of which, moreover, long-term securing of underground cavities is possible at a reasonable economic cost.

[0004] This problem is solved according to the invention by a method for securing underground cavities against collapse and incursions using artificial mineral fibers, in which the artificial mineral fibers are pressed into bales, in which the artificial mineral fibers pressed into bales are tightly wrapped with foil, in which a layer of foil-wrapped bales is applied to the base of an underground cavity, in which a cover layer is applied to the layer of foil-wrapped bales, and in which further layers of foil-wrapped bales and further cover layers are applied alternately until a ceiling or ridge area of ​​the underground cavity is reached.According to the invention, underground cavities are secured against collapse and intrusion in the long term, and artificial mineral fibers can be stored safely and without risk over the long term without any hazardous excavation processes. The encased bales made from the artificial mineral fibers significantly increase the stability of support pillars or retaining walls in the underground cavities.

[0005] To minimize risks during handling and transport of the bales made of compressed artificial mineral fibers, the compressed artificial mineral fibers are advantageously wrapped with film until the bale is fully and overlappingly covered with film, whereby a full-surface and overlapping wrapping of several, preferably three to five, layers has proven to be particularly advantageous.

[0006] The films used should ideally be hygienic, tear-resistant, fire-resistant or flame-retardant, and preferably approved for use in mining operations. These latter films could, for example, be registered under a state mining authority number.

[0007] The foil-wrapped bales are manufactured with dimensions such as approximately 750 mm in height, 1,100 mm in width, and an adjustable length, preferably around 1,200 mm, to simplify handling and transport. Standard pallets can be used to transport these bales. Deviations from these exemplary dimensions are possible depending on the type and design of the pressing device used.

[0008] To ensure that unnecessary stresses and thus potential damage to the wrapped bale forms do not occur before they are placed in the underground cavity, an advantageous embodiment of the inventive method proposes applying a leveling layer to the bottom of the underground cavity before the first layer of wrapped bale forms is applied. This leveling layer also ensures a level surface.

[0009] Advantageously, backfill material, spoil from processing and / or a sand-gravel mixture is used for the leveling layer and the covering layers.

[0010] The layers are expediently produced from one or two layers of foil-covered bale forms.

[0011] The leveling layer and the cover layers can expediently have a thickness of approximately 1.0 to 1.5 m, although the leveling layer can also be thinner. Depending on the material used for the leveling layer, its thickness can vary.

[0012] To increase the stability of the leveling layer and the cover layers, it is advantageous if the leveling layer and the cover layers are compacted from foil-wrapped bales before the first or next layer is applied, whereby a tracked vehicle or a comparable device can preferably be used for the compaction process.

[0013] Alternatively, the bale-shaped molds can be inserted head-on into the underground cavity. Alternatively, the bale-shaped molds can be inserted laterally along the underground cavity.

[0014] To increase stability, it is advantageous to stack the bale-shaped forms in a staggered 3 / 4 pattern. Since the load on the film-wrapped bale-shaped forms increases with each layer, the spacing or stacking pattern can be adjusted.

[0015] An increase in the security of the underground cavity can be achieved if a residual cavity in the ridge area of ​​the underground cavity between the ridge and the top layer is filled with foil-wrapped bale forms using blown-in offset.

[0016] Undesirable weather passages or losses can be avoided if a series of foil-wrapped bale forms is placed at the entrance and / or at the end or exit of the underground cavity in its ridge area.

[0017] The invention will now be explained in more detail with reference to embodiments and the drawings. The drawings show: Fig. 1 a principal cross-sectional representation of an underground cavity, in which an embodiment of the inventive method for securing underground cavities against incursions and collapses is implemented using artificial mineral fibers; Fig. 2 a principal longitudinal representation of an underground cavity by realizing a further embodiment of the method according to the invention; Fig. 3 one Fig. 1 corresponding cross-section, which shows the in Fig. 1 shows the inventive process according to the invention in principle according to further process steps; Fig. 4, approximately Fig. 2 corresponding longitudinal representation, in which a third embodiment of the method according to the invention is shown after further process steps; Fig. 5 one the Fig. 1 and Fig. 3. Corresponding cross-sectional view of the underground cavity, which is filled up to the roof area by means of the first embodiment of the method according to the invention; and Fig. 6 a basic longitudinal representation of the underground cavity, which according to the already in Fig. 4 shown third embodiment of the method according to the invention, until it is filled up to its ridge area.

[0018] Based on the Fig. 1, Fig. 3 and Fig. Section 5 now describes a first embodiment of a method according to the invention for securing underground cavities against collapse and intrusion using artificial mineral fibers. Fig. 1, Fig. 3 and Fig. Figure 5 shows an underground cavity 1 in a principal cross-sectional view, wherein in Fig. 1 the cavity 1 in the initial stage of the process, in the case of the Fig. 3 during a middle phase of this process and in Fig. Figure 5 is shown in the final stage of the process. In this regard, it should also be noted that the representation of cavity 1 in all Fig. Points 1 to 6 are merely in principle. Such an underground cavity 1 can have different dimensions in terms of its width, height, and length. For example, such an underground cavity can be 10 meters wide, 27 meters high, and up to 200 meters long.

[0019] The artificial mineral fibers intended for the process are first compressed into bales 2. For this purpose, the artificial mineral fibers are subjected to a pressing pressure, which can be predetermined according to the requirements profile, using a suitable pressing tool and formed into the bale shape 2 shown in the figures. In order to be able to handle, transport, and store these compressed artificial mineral fibers 2, they are secured by means of plastic / metal bands, ropes, or wires and tightly wrapped with a hygienic, tear-resistant, fire-resistant, or flame-retardant film 3, preferably approved for use in mining. The wrapping process is carried out in such a way that the bale 2 is completely and overlappingly covered with multiple layers, preferably 3 to 5 layers, of film 3 when the wrapping process is complete.The resulting bale-shaped forms made of artificial mineral fibers are then transported by suitable transport devices to the deposition area, which is the one in the . Fig. 1, Fig. 3 and Fig. The material is transported to the underground cavity 1 shown in Figure 5. Suitable transport vehicles such as trucks, disposable pallets, underground transport vehicles, low-loader trailers, roll-off containers, or similar vehicles can be used. The actual handling of the bale-shaped forms 2 wrapped in film 3 within the underground cavity 1 is then carried out, for example, using telescopic handlers equipped with a special gripping tool suitable for the respective bale-shaped forms 2.

[0020] According to the in the Fig. 1, Fig. 3 and Fig. In the exemplary embodiment of the method according to the invention shown in Figure 5, the bale forms 2 are inserted head-on into the underground cavity 1, which may, for example, be a chamber. Before the bale forms 2 are inserted into the underground cavity 1, a leveling layer 5 is applied to a floor 4 of the underground cavity 1 in the illustrated embodiment of the method according to the invention. This leveling layer 5 can be made of backfill material, spoil from processing, and / or a sand-gravel mixture. Of course, it is possible to omit such a leveling layer 5 if the floor 4 of the underground cavity already possesses sufficient properties for the storage of the bale forms 2 without such a leveling layer 5.

[0021] In the next process step, the bale forms 2, wrapped with film 3 and which may, for example, have a height of approximately 750 mm, a width of approximately 1,100 mm and a length of approximately 1,200 mm, are wrapped by means of a device that is only partially enclosed in Fig. The telescopic loader 6 shown in section 2 was moved into the underground cavity 1, whereby in the case of the telescopic loader shown in section 2, the material was transported into the underground cavity 1, and the material was transported into the underground cavity 1. Fig. 1, Fig. 3 and Fig. In the embodiment of the method according to the invention shown in Figure 5, the bale forms 2 are placed frontally into the underground cavity 1. As soon as a layer 7 of bale forms 2 is arranged on the floor 4 or the leveling layer 5, which in the case of the Fig. 1, Fig. 3 and Fig. In the embodiment 5 of the inventive method, which consists of a layer of the aforementioned bale forms 2, a cover layer 8 is applied to this layer 7 of bale forms 2 wrapped with film 3. This cover layer 8, like the leveling layer 5 applied to the floor 4 of the underground cavity 1, also consists of backfill material, spoil from the processing, and / or a sand-gravel mixture. When this cover layer 8 is applied to layer 7, any voids that may exist between the bale forms 2 and the walls or joints of the underground cavity 1 are filled with the material forming the cover layer 8. A further layer 9 of bale forms 2 wrapped with film 3 is then deposited on this cover layer 8 in the manner already described. This further layer 9 is also covered with a further cover layer 10 after its application.The bale-shaped forms 2 of the further layer 9 are deposited in a 3 / 4 offset pattern relative to the bale-shaped forms 2 of layer 7 arranged below them. During the construction of the second cover layer 10, any voids between the bale-shaped forms 2 of the further layer 9 and the walls or joints of the underground cavity 1 are filled with the material forming the further cover layer 10.

[0022] In Fig. Figure 3 shows the inventive method after the process step in which the further cover layer 10 is applied to the further layer 9 from bale forms 2. Naturally, it is possible for the leveling layer 5 and the cover layers 8, 10 to be compacted after their application, whereby a tracked vehicle 11 can be used for both the application and the compaction process, as is shown in Fig. Figure 4 shows that the cover layers 8 and 10 can have a thickness of approximately 1.0 to 1.5 m. In principle, the leveling layer 5 can also be this thick, but its thickness is usually less. The following are shown in the Fig. 3 and Fig. The cover layer 10 shown in Figure 5 is covered in the manner already described by a further layer 12 consisting of bale forms 2 wrapped in film 3, a further cover layer 13, and a further layer 14 consisting of bale forms 2 wrapped in film 3. In the case described in the Fig. 1, Fig. 3 and Fig. In the embodiment of the method according to the invention shown in Figure 5, the further layer 14 of bale forms 2 wrapped with foil 3 is already arranged in a ridge area of ​​the underground cavity 1. A residual cavity 16 in the ridge area 15 of the underground cavity 1, which exists between the ridge 17 of the underground cavity 1 and the uppermost layer 14 of bale forms 2 wrapped with foil 3, can be filled, for example, with blown-in backfill.

[0023] By means of the above-described inventive method for securing underground cavities against collapses and cave-ins using the ball forms 2 made of artificial mineral fibers wrapped with foil 3, on the one hand an increase in the stability of the mine structures surrounding the underground cavity 1 can be achieved, and on the other hand a safe and risk-free handling and use of the problematic artificial mineral fibers can be ensured.

[0024] One in Fig. The embodiment of the method according to the invention, as described in principle, differs from the one described above based on the Fig. 1, Fig. 3 and Fig. The embodiment described in section 5 is characterized, firstly, by the fact that the bale forms 2 wrapped with film 3 are deposited laterally along a side wall of the underground cavity 1 using the telescopic loader 6. Furthermore, the Fig. The two methods shown in principle differ in that a layer 7, 9, 12, or 14, consisting of bale forms 2 wrapped with foil 3, is designed in two layers. That is, on the base 4 of the underground cavity 1 or on the leveling layer 5 applied thereon, bale forms 2 wrapped with foil 3 are first placed in two layers before a cover layer 8, 10, 13 is applied to the upper layer. When applying the cover layer 8, the voids between the foil-wrapped bale forms 2 on the one hand and the wall of the underground cavity 1 on the other hand are filled with the material forming the cover layer 8. In the Fig. 4 and Fig. In the embodiment of the method according to the invention shown in Figure 6, the bale forms 2 wrapped with foil 3 are deposited laterally along a side wall of the underground cavity – as in the case of the Fig. 3 embodiment of the method shown - however, the embodiments of the method as shown in the 3 are different. Fig. 4 and Fig. As shown in Figure 6, the formed layers 7, 9, 12 and 14 are only single layers. Cover layers 8, 10 and 13 are provided between these layers 7, 9, 12 and 14, which are also produced in the manner already described.

[0025] It is possible to arrange another row of foil-wrapped bales 2 at the entrance and, if applicable, the exit of the underground cavity 1 on top of the uppermost layer 14 of foil-wrapped bales 2, in order to prevent unwanted airflow and losses. Of course, it is also possible to fill the remaining cavity 16 in the ridge area 15 with blown-in fill instead.

Claims

[1] Method for securing underground cavities (1) against collapse and incursion, in which artificial mineral fibers are compressed into bale shapes (2), in which the artificial mineral fibers compressed into bale shapes (2) are tightly wrapped with foil (3), in which a layer (7) of foil-wrapped bale shapes (2) is applied to a floor (4) of an underground cavity (1), in which a cover layer (8) is applied to the layer (7) of foil-wrapped bale shapes (2), and in which further layers (9, 12, 14) of foil-wrapped bale shapes (2) and further cover layers (10, 13) are applied alternately until a ceiling or ridge area (15) of the underground cavity (1) is reached. [2] Method according to claim 1, wherein the artificial mineral fibers pressed into a ball shape (2) are wrapped with the film (3) until the ball shape (2) is completely and overlappingly covered with film (3). [3] Method according to claim 2, wherein the film (3) is wrapped over the entire surface and overlapping in 3 to 5 layers onto the bale form (2). [4] Method according to any one of claims 1 to 3, wherein hygienic, tear-resistant, fire-resistant or flame-retardant film (3) and preferably approved for use in mining is used. [5] Method according to any one of claims 1 to 4, wherein the ball forms (2) wrapped with film (3) are produced, for example, with a height of approximately 750 mm, a width of approximately 1,100 mm and an adjustable length, preferably of approximately 1,200 mm. [6] Method according to any one of claims 1 to 5, wherein a leveling layer (5) is applied to the floor (4) of the underground cavity (1) before the application of the first layer (7) of foil-covered bale forms (2). [7] Method according to any one of claims 1 to 6, wherein backfill material, spoil from processing and / or a sand-gravel mixture is used for the leveling layer (5) and the cover layers (8, 10, 13). [8] Method according to any one of claims 1 to 7, wherein the layers (6, 9, 12, 14) are produced from foil-covered ball forms (2) from one or from two layers of foil-covered ball forms (2). [9] Method according to any one of claims 1 to 8, wherein the leveling layer (5) and the covering layers (8, 10, 13) are produced with a layer thickness of approximately 1.0 to 1.5 m. [10] Method according to any one of claims 1 to 9, wherein the leveling layer (5) and the cover layers (8, 10, 13) are compacted from foil-wrapped bale forms (2) before the application of the first (7) or the next layer (9, 12, 14), preferably with a tracked vehicle (11) or a comparable device. [11] Method according to any one of claims 1 to 10, wherein the bale forms (2) are inserted frontally into the underground cavity (1). [12] Method according to any one of claims 1 to 10, wherein the ball shapes (2) are inserted laterally along the underlying cavity (1). [13] Method according to any one of claims 1 to 12, wherein the bale forms (2) are stacked in a staggered 3 / 4 arrangement. [14] Method according to one of claims 1 to 13, wherein a residual cavity (16) in the ridge area (15) of the underground cavity (1) between the ridge (17) and the uppermost layer (14) is filled with foil-covered bale forms (2) using blown-in backfill. [15] Method according to any one of claims 1 to 13, wherein a series of ball forms (2) wrapped with foil (3) is deposited at the entrance and / or at the end of the underground cavity (1) in its roof area (15).

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