LINING OF ROCK-FACES SUCH AS TUNNELS AND THE LIKE, AND A METHOD TO PROVIDE THE LINING

Abstract: Lining of rock-faces, such as tunnels and the like, as a protection against water running down, ice formation and falling rock, which lining (10) is provided at some distance from the rock-face (15), and mounted on support means (14 and/or 16), which are firmly anchored in the rock-face (15), and which lining consists of boards, which adjacent end surfaces are connected to each other, forming a continuous waterproof protection layer. The protection layer consists of plane and/or single-curved thermal insulation plates (11) of a waterproof material, which on at least one of the flat sides preferably on both flat sides are covered by reinforcement nets (12) or the like, to which the support means (14 and/or 36) are attached.

Description: LINING OF ROCK-FACES SUCH AS TUNNELS AND THE LIKE, AND A METHOD TO PROVIDE THE LINING Technical field The present invention refers to a lining of rock-faces, such as tunnels and the like, as a protection against water running down, ice formation, falling rock, which lining is provided at some distance from the rock- face, and mounted on supporting means, which are firmly anchored in the rock- face, and which lining consists of plates, the adjacent end surfaces of which are connected to each other, forming a continous water proof protection. Background of the invention Road, train and track tunnels at northen latitudes have large problems at winter with formation of ice at roofs and walls because of badly working drainage or bad sealings made during the injection. In the last few years there have been attempts to solve this problem by lining the tunnel faces with insulating mats, so that the rock surfaces are held at a temperature above zero. In the event of water is leaking in this may run between the rock and the insulation to a draining layer at the bottom of the tunnel. The mounting of these insulation elements be¬ cause of the roughness of the rock has been a troublesome put together work and at many localities resulted in bad function because of leakage around bolts and in joints, which are glued on the spot. Through DE- B2 - 1.940.050 is known to use a lining as a remaining mould, between which and the rock-face is placed concrete. The lining consists of plastic plates which on both sides are covered by a covering layer of metal, and which plastic plates are connected to each other by means of welding. According to a second variant the rock wall is lined with a sprayed concrete layer and at some distance from this the lining consisting of plastic plates is loca¬ ted, which lining is connected with the sprayed concrete layer by anchoring irons. In both variants the rough rock face is evened by means of a relatively solid concrete layer, which is a necessity to be able to use the relatively thin plastic plates, which only are intended to drain off water, but does not have any possibility to absorb such loads which may occur if stones are broken off from the rock face and which fall down on the lining. Both variants are expensive in manufacture, which also applies to the manufacture of the protection layer, which consists of 3-10 mm thick plastic plates, which either have to be welded from the rear side, that is the side facing the cliff, or that the connection between the plastic discs is carried out by means of special jaws which are arranged along the connection edges, which jaws have to be formed after the curve of the tunnel vault. Since frost insulation works performed up to now have shown various problems there have been put forward desires of a well prepared system for mounting a tunnel lining. As this type of construction hides the rock surfaces, which thereby become unavailable for inspection, there is a risk for stones falling down through the construction, inasmuch as special measures are not taken to reinforce the rock before the lining is mounted. Objects of the invention and most essential features The object of the invention is to provide a rock face lining of the type stated by way of introduction, which is flexible and adaptable to tunnels of different length and cross section arid which in addition to preventing water from leaking into the tunnel also constitutes a good protection against falling rock. The structure should be simple to repair after damage and easily can be provided with a satis¬ factory fire protection. This has according to the invention been achieved by the protection layer consisting of plane and/or single- curved thermal insulation plates of a water proof material, which at least on one of the flat sides, preferably on both flat- sides are coated with a reinforcement net or the like, to which the support means are fixed. The invention further refers to a method to perform the lining of rock-faces, which method is characterized in that on the support means the protection layer is mounted consis¬ ting of plane and/or single curved thermal insulating discs of water proof material and on at least one and preferably both flat sides is applied a reinforcement net or the like, to which the support means are connected. Description of the drawings In the following the invention will be described in detail with reference some embodiments shown in accompanying dra¬ wings. Fig. 1 is a diagrammatic sectional view through a tunnel provided with a lining according to a first embodiment of the invention. Fig. 2 shows in a larger scale a section through a part of the lining according to fig. 1. Fig. 3 shows a section analogous to that of fig. 2 of the lining just in front of an overlap joint. Fig. 4 shows a section along the line IV-IV in fig. 5 through a modified embodiment of the connection device according to the invention. Fig. 5 shows a longitudinal section through a part of the lining according to the embodiment shown in fig. 4. Fig. 6 shows a section through a part of a tunnel, where the lining is supported by longitudinal beams. Fig. 7 shows a longitudinal section through a further embodiment of a part of the lining. Fig. 8 shows a view analogous to that of fig. 6 of the lining, where the joint between the insulation plates is constituted by a concrete beam. Fig. 9 shows an enlargement of the portion encircled in fig. 6. Fig. 10 shows an enlargement of the portion encircled in fig. 7. Fig. 11 shows a section through a lining with a clamp in the form of a yoke and a hook. Fig. 12 shows an end view of a beam with an alternative connection device. Fig. 13 shows a joint between two beams connected to each other end by end. Description of embodiments The lining according to the invention, in the drawings designated with 10, is constituted by a number of insulation plates 11, of a water proof material, e.g. foamed plastic, with closed pores, and on both sides of the board provided reinforcement nets 12 located to fit-up against the flat sides of the insulating boards 11. The reinforcement nets may preferably consist of galvanized steel rods, 5-6 mm in diameter, with a mesh width of e.g. 10-15 cm, and which lining parts are kept together by suitable connection devi¬ ces 17, forming an integrated protection layer. This means that the protection layer can absorb even relatively large loads, such as stones torn off, in the order of magnitude up to 3 tons, without collapsing the protection layer. The lining 10 is mounted to the rock face 15 by means of carrier means 14, which in the embodiment shown in fig. 1-3 are constituted by rock bolts 13, the part of which is located outside the rockface is constituted by an attachment device 16, in the form of a threaded bar, on to which the lining 10 is secured. The lining 10 is spaced from he rock- face 15 by means of spacing means 24, which in the embodi¬ ment shown according to fig. 2 is constituted by a nut 25 threaded onto the rock bolt 13 and a support washer 26. The lining 10 is fixed to the rock bolt by means of a clamping device 27, in which is contained the attachment device 16, the nut 25, the support washer 26 on one side of the lining, and a second support washer 28 and a second support washer 28 and a second nut 29 on the other side of the lining. The mounting of the lining against the rockface is carried out by drilling rock bolts into the rock with a center distance suitable to carry the lining 10. On the threaded attachment device 16 the nut 25 is applied at suitable distance from the rock face and the support washer 26 is applied. Thereafter the first inner reinforcement net 12 is hanged on to the attachment device 16 and the soft isulation board is thread on these, whereafter the second outer reinforcement net 12 is applied on the top of the insulating board. The support washer 28 and the nut 29 are applied and tightened, so that the insulation plate is effectively fixed between the reinforcement nets 12. The insulation plates 11 are supplied in oblong lengths (usual dimension 0,6 x 2,7 m) and in order to obtain water proof joints between the insulation plates, the overlapping joint 30 shown in fig 3 can be useful. This may consist of the jointing pieces 31, which in a suitable way are secured to the flatside of the board along two side edges with so large overhang, that an effective connection with an adja¬ cent insulation plate is obtained. The connection between the overlap joints is provided by means of e.g. a water proof glue. As is evident from fig. 3 the clamping device 27 is located just in front of such a joint, whereby a good pressing between the jointing pieces is obtained. According to a second embodiment, shown in fig. 4 and 5, the lining 10 is supported by a number of supporting means 14, which consist of beams 18 which are arranged in longi¬ tudinal lines, which in turn are secured to the rock face 15 by rock bolts 13. The supporting means 14 also comprise connection devices 17, which are constituted by short tube pieces 33 with larger internal extension than the beams 18, which may be constituted by steel profile beams, with e.g. rectangular cross section. The connection devices, that is in this embodiment the tube pieces 33, are secured to the securing means 16 of the rock bolts in such a way, that they are spaced from the rock face 15, and such that the beams 14 can be pushed into these forming a system of beams of prefe¬ rably parallel lines. To prevent the beams 14 from being displaced relatively the connection devices 17, these may be provided with a clamp screw, which acts on the beam 18. On the side of the connection device 17 facing inwards, that is on the side which is turned from the rock face 15, perpendi¬ cular to this can be provided a threaded pin 36, on to which the lining 10 can be threaded, in the same way as has been described above in connection with the first embodiment. As is evident from fig. 5 the distance between the connec¬ tion devices 17 can be larger than the center distance between the clamping device 27, which support the lining 10. This distance is bridged by means of further tube pieces 35, which lack the connection with the rock bolt 13, and thus are freely displaceable along the beam 18, so that an app¬ ropriate position with respect to the lining can be obtai¬ ned. The tube pieces 35 are provided each with a threaded pin 36, as an attachment for the lining. The embodiment according to fig. 6 - 13 differs from the previous embodiment in that the reinforcement nets 12 and the insulation 11 is kept together by a number of clamping means 27, which in this embodiment - fig. 11 - is constitu- ted by yokes 19, which at both ends are formed with hookes, of which one is axially displaceable with respect to the fixed hook and can be tightened by means of a nut. The yokes 19 can also be used to connect the lining with the connec¬ tion device 17, the threaded pin 36 of which for this purpo¬ se at one of its free ends is formed with a hook, which is hooked into one of the hooks of the yoke 19. In the embodiment according to fig. 7 - 13 the connection device 17 formed as a tightening device 32, the gripping jaws 37 of which can be tightened by means of a link 38, e.g. in the form of a screw and nut. The screw can be an extension of the rock bolt 13, If the tightening device is going to be connected to the rock face or as well be that part which connects the clamping means 27 with the connec¬ tion device 17. The screw 38 can also be in itself the securing means (corresponding to the attachment device 16) which supports the lining 10. The link 38 also in a third embodiment has the form of a hook, which can be hooked to the beam 18. On top of the outer reinforcement net 12 a thin layer of spray concrete can be applied, to reduce the fire hazard, and to reinforce the construction. Such a fire protection is required e.g. in tunnels for road traffic, while on the other hand in e.g. train tunnels the the fire protection has not be as extensive. In such cases the sprayed concrete 20 can be excluded, whereby the nets 12 function merely as reinforcement of the insulation 11. In structures with sprayed concrete layers, the net 12 also functions as a reinforcement of the concrete layer. The joints between adjacent linings 10 either can be a dummy joints or overlapping joints (fig. 9) and are preferably glued to obtain the necessary density. If the outermost reinforcement net 12 is to be covered by a concrete layer, e.g. every second joint according to fig. 8 and 10 can be formed as a so called "concrete rib" 21, that is a beam between the edges of the insulating boards 11, which is provided by a recess between the boards, which is filled with sprayed concrete. The mounting of the lining according to the invention is performed in the following way. The rock bolts 16 are attac¬ hed in the rock- face 5 and to these the beams are attached by means of the connection devices 17 in oriented lines, preferably in the longitudinal direction of the tunnel. The lining 10, which is manufactured on the site or is prefabricated in a factory in the form of cassettes, is thereafter mounted on the beams 14 and adjacent insulating and the end edges of the insulation plates 11 are joined water proof, so that a continuous lining is formed. A sprayed concrete layer thereafter is applied on the inside of the lining if a fire protection is desired. Of course the invention is not limited to the embodiments shown, but several modifications are possible within the scope of the claims. The construction according to the invention fulfils high requirements, it is proof against leaking water, even in the joints, since the lining is substantially plane or possibly single- curved. It isolates against frost, so that water which leaks out of the rock will run along the backside of the lining down to the drain-pipe. It protects against falling rock through the "tough" construction which is provided by means of reinforcement nets on both sides of the insulation. It can be provided with an acceptable fire protection. It can be made resistant by suitable choice of material. It also stands variations at pressure stresses. It can also be repaired after damage, since it is possible to replace separate insulation plates. It can also be adapted to tunnels with different cross sections and dimensions. DISPOSITION OF REFERENCE DESIGNATIONS lining, protection layer insulation plate reinforcement net rock bolt support means, e.g. rock bolt 13 or beam 18 rock face attachment device connection device beam yoke sprayed concrete concrete rib spacing means l:st nut l:st support washer clamping device 2:nd support washer 2:nd nut overlap joint joint piece tightening device tube piece clamp screw tube piece threaded pin face plate jaw link

Claims: CLAIMS 1. Lining of rock-faces, such as tunnels and the like, as a protection against water running down, ice formation and falling rock, which lining (10) is provided at some distance from the rock-face (15), and mounted on support means (14 and/or 16), which are firmly anchored in the rock-face (15), and which lining consists of boards, which adjacent end sur¬ faces are connected to each other, forming a continuous waterproof protection layer c h a r a c t e r i z e d t h e r e i n that the protection layer consists of plane and/or single- curved thermal insulation plates (11) of a water proof material, which on at least one of the flat sides preferably on both flat sides are covered by reinforcement nets (12) or the like, to which the support means (14;16;36) are attac¬ hed. 2. Lining according to claim 1, c h a r a c t e r i z e d t h e r e i n, that the reinforcement nets (12), which are applied on the both flat sides of the insulation plates, are connected to each other by means of clamping devices (27) formed to integrate the reinforcement nets with the insulation, where¬ by one of the nets can serve as a reinforcement for a spray¬ ed concrete layer (20). 3. Lining according to claim 1 or 2, c h a r a c t e r i z e d t h e r e i n, that the support means (14) are constituted by preferably in longitudinal lines oriented beams (18), which by means of rock- bolts or the like are firmly attached at and at some distance from the rock-face (15), and that the beams (18) by means of connection devices (17) are attachable to the rock bolts (16). 4. Lining according to claim 3, c h a r a c t e r i z e d t h e r e i n, that the support means (14) are constituted by said beams (18) and/or rock bolts (13) provided with spacing means (24) for spacing of the cassettes (10) from the rock-face. 5. Lining according to claim 1, c h a r a c t e r i z e d t h e r e i n, that the cassettes (10), by means of links (38), e.g. in the form of pendulums are hookable in the beams (14). 6. Lining according to claim 3, c h a r a c t e r i z e d t h e r e i n, that the connection device (17) is constituted by the tube pieces (33,35), which are threadable on and displaceable along the beams (18), and of which certain are attached to the rock-bolts (13) and certain are provided with an attach¬ ment device (36) for supporting the lining (10). 7. Lining according to claim 3, c h a r a c t e r i z e d t h e r e i n, that the connection device (17) is constituted by a tigh¬ tening device (32), which by means of face plate jaws (37) is braceable to the beam (18). 8. Method for lining of rock-faces for tunnels or the like, according to claim 1, as protection against water running down, ice formation and falling of rocks by means of a protection layer (9), which is applied at some distance from the rock-face and is anchored in this by means of support means (14;13), c h a r a c t e r i z e d t h e r e i n, that the protective layer is mounted on the support means, which layer consists of plane and/or single-curved thermal insulation plates of water proof material and on at least one of preferably on both flat sides a reinforcement net (12) or the like is applied, to which the support means is connected. 9. Method according to claim 6, c h a r a c t e r i z e d t h e r e i n, that the lining (10) is mounted on support means (14) in the form of beams (18) arranged in longitudinal lines, which beams are attached to rock bolts (16) or the like anchored in the rock face. 10. Method according to claim 6 or 7, c h a r a c t e r i z e d t h e r e i , that the insulation plates (11) of the lining (10) on both sides are covered by a reinforcement net (12), which are connected to each other by means of in the direction of the insulation bord tightenable yokes (19) which are thread through the insulating boards and hooked into the reinfor¬ cement nets (12). 11. Method according to claim 8, c h a r a c t e r i z e d t h e r e i n, that in the yokes (19), hookes (19) are inserted and fixed, i order to get connection with the support means (14 or 16).

Inventors: KARLSSON LENNART, KARLSSON, LENNART
Applicants: BERGSAEKER KONSULT AB
Application year: 1991
Main classification: E21D11
IPC codes: E21D11