FI83807B - Rock reservoir or tunnel - Google Patents

Description

83807 1 Rock reservoir or tunnel Bergsbehallare eller tunnel 5

The invention relates to a rock reservoir or tunnel whose inner surface of the wall structure is a dense coating, preferably reinforced plastic, and between the excavated rock surface and the inner surface there is a concrete layer, preferably a water permeable porous concrete , which is adapted to distribute the stresses caused by the shrinkage phenomena to the inner surface at regular intervals so that the maximum allowable tensile strength of the inner surface is not exceeded at any point on the inner surface.

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Caves excavated in the rock are known to be used to store various liquids and gases without coating. In these cases, the products to be stored are immiscible in water and lighter in water. The stability of liquids and gases in storage is based on the higher pressure of the water surrounding the rock cave than that of the product to be stored. However, if the storage pressure of the liquid or gas to be stored is high, the caves will have to be dug unreasonably deep, which will incur high costs.

When using rock caverns, e.g. for the storage of natural gas, the natural gas 25 is generally pressurized or liquefied and in both cases cooled to very low temperatures. However, coating the gas tank in a cautious manner is problematic because, in addition to preventing gas permeability, the coating must withstand the thermal movements due to the different thermal expansion coefficients of the rock mass and the structures under the coating and the forces and stresses caused by them. Thermal expansion causes cracks and fissures in the coating, which are usually concentrated at certain points in the coating.

It is known to coat a rock wall with shotcrete and to seal such a coating with a plastic coating. In these solutions, however, the above-mentioned cracks caused by thermal expansion break the coating.

2 83807 1 FI patent 69503 discloses a rock reservoir or tunnel in which between the excavated rock surface and the reinforced waterproof shotcrete layer there is a highly permeable shotcrete layer acting as a groundwater conductive layer. The solution is primarily aimed at eliminating the damage caused by groundwater and thus making a dense coating and allowing it to remain in its substrate. On the other hand, the solution allows the uneven rock surface to be leveled after excavation, so that it is possible to make thick reinforced plastic coatings.

A previously known solution for the wall structure of a rock-dug cave is disclosed in U.S. Patent No. 34,188,812. the edges can move freely. However, in this previously known solution, the dense inner coating is firmly attached to the surface of the inner panels throughout. This partially limits the problems caused by thermal expansion, but the risk of cracking of the inner coating still exists. In addition, the solution is multi-20 complicated.

Another previously known insulating layer solution for the wall structure of a rock cave is disclosed in U.S. Patent No. 4,199,909.

The object of the invention is to provide a wall structure of a rock reservoir or tunnel which is gas-tight and which remains intact despite thermal expansion / contraction at operating temperatures.

In order to achieve the above objects and the advantages that will emerge later, the gas tank or tunnel according to the invention is mainly characterized in that the substructure is detached from both the inner surface and the concrete layer.

Other advantageous features of the invention are set out in claims 2-3.

The wall structure of a rock wall or tunnel according to the invention preferably distributes the stresses caused by thermal expansion / contraction to the dense inner surface, whereby the inner surface is not broken as a result of cracks caused by the stresses. This keeps the tank tight.

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In the following, the invention will be described in detail with reference to a preferred embodiment of the invention shown in the figures of the accompanying drawing, to which, however, the invention is not intended to be narrowly limited in any way.

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Figure 1 shows a schematic cross-section of a preferred embodiment of a container according to the invention.

Fig. 2 shows a detail A of Fig. 1 on a larger scale 15 seen from the side.

Fig. 3 shows a detail A of Fig. 1 seen on a larger scale from above.

In the embodiment according to Figure 1, the rock reservoir or tunnel is generally indicated by reference numeral 10 and the excavated rock surface is denoted by reference numeral 14. Reference numeral 15 denotes rock bolts by means of which the walls of the rock reservoir or tunnel 10 are reinforced in a manner known per se. The inner surface of the rock tank wall structure-25 is marked with the reference number 11. The piping and equipment for pumping the products in and out are not shown in Figure 1.

According to Fig. 2, the mosaic pieces 16 form a region structure 12. Through the mosaic pieces 16 of the vessel-30 structure 12, adhesions 18 are arranged in the concrete layer 13 from the inner surface 11. The gaps between the mosaic pieces 16 are denoted by reference numeral 17. On the other hand.

The area structure 12 is attached to the inner surface 11 and the concrete layer 13 only at its gripping points 18, so that in other respects it is detached from both the inner surface 11 and the concrete layer 13.

In Fig. 3, the area structure consisting of the mosaic pieces 16 is further denoted generally by reference numeral 12. According to Fig. 3, the grips 18 are located in the centers of the mosaic pieces 16.

The operation of the liquid tank 1 or tunnel 10 is based on the fact that the inner surface 11 is tight and thus prevents the substance to be stored, e.g. natural gas, from escaping from the tank 10. At the same time, the inner surface 11 acts as a pressure tank against the area structure 12. The area structure 12 consisting of the mosaic pieces 16 acts as a pressure transmitter to the outer concrete layer 13 and to the rock surface 10 IA. At the same time, the area structure 12 consisting of the mosaic pieces 16 acts as a bearing layer for heat movements and stresses in the direction of the wall structure, since it is not attached to the gas-tight inner surface 11 or the concrete layer 13, except for its gripping points 18.

15 The size of the mosaic piece 16 has been calculated in such a way that the thermal movements generated in the operating temperature range of the rock reservoir or tunnel 10 in question do not damage the sealed inner surface 11.

In addition, the seams between the mosaic pieces 16 act as a diffused gas path through the inner surface 11 20 to the drainage network in the concrete layer 13 (not shown in the figures). In this case, the area structure 12 consisting of the mosaic pieces 16 remains firmly in the walls of the rock reservoir or tunnel 10, even in the roof, while the pressure still helps.

The area structure 12 of the mosaic pieces 16 allows the concrete layer 13 of the rock tank or tunnel 10 to be cast in suitable widths without a discontinuous seam on the inner surface 11. The area structure 12 of the mosaic pieces 16 acts as a casting mold forms.

The area structure 12 is made either of individual mosaic pieces 16 by assembling, leaving gaps 17 between the mosaic pieces, or by means of a honeycomb directly to the isäplnnolttee le 11, which may be e.g. reinforced plastic, a mold 35, whereby the points indicated by reference numeral 17

5 83807 ^ The mosaic-faced inner surface panels are joined together by a butt seam which is roughened and laminated on top with glass fibers in a manner known per se.

Only certain preferred embodiments of the invention have been described above, and it will be clear to a person skilled in the art that numerous modifications can be made to them within the scope of the inventive idea set out in the following claims.

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Claims (3)

6 83807 A rock reservoir or tunnel (10), the inner surface (11) of the wall structure of which is a tight coating, preferably reinforced plastic, and between the excavated rock surface 5 (14) and the inner surface (11) there is a concrete layer (13), preferably a water permeable porous bottom a concrete layer, and between the inner surface (11) of the rock reservoir (10) and the concrete layer (13) there is a zone structure (12) consisting of mosaic pieces (16) adapted to distribute the stresses kut0 due to thermal expansion, evenly spaced on the inner surface (11), that the maximum permissible tensile strength of the inner surface (11) is not exceeded at any point in the inner surface (11), characterized in that the area structure (12) is detached from both the inner surface (11) and the concrete layer (13). 1 Claims Rock tank according to Claim 1, characterized in that the grips (18) directed from the inner surface (11) to the concrete layer (13) are adapted to pass through the mosaic pieces (16) of the area structure (12). Rock reservoir according to Claim 1 or 2, characterized in that the moss pieces (16) are cast by means of a honeycomb. 25 30 35 7 83807