ES2659022T3 - Entibación in civil engineering works - Google Patents

Abstract

Construction has a seal secured at the outer side against traversing water or a anchor isolation against corrosion or a film with rough surface or a claw mat or an agent for spraying concrete with enclosed plastic foam particles. The film is held by means of sealing elements at the anchoring elements.

Description

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DESCRIPTION

Entibación in civil engineering works

The invention relates to an entibación in civil engineering works, especially to a shoring of underground spaces such as tunnels and galleries or pipes in solid rocks.

The fasteners are used with special frequency in the tunneling of tunnels. It is necessary to differentiate between tunnels in solid rock and tunnels in non-solid rock. A solid touch does not sink after the tunnel excavation. In a non-solid rock, on the other hand, a resistant tunnel shroud capable of partially absorbing the weight of the rock is needed. In non-solid rocks, both steel and concrete pipes are usually used. Steel and concrete combinations can also be used. Concrete shoring can be manufactured in most cases on site. Prefabricated concrete panels that are transported to the site are also usual.

In solid rock, this resistance problem does not exist.

The problem of protection against falling stones remains. This problem is usually solved by means of shotcrete. The concrete is projected against the excavation area where a protective coating is forged and forms.

Another problem is that of the water from the rock that comes out. In winter, the water freezes. There is a risk of falling ice masses. This risk is traditionally prevented with a laminar gasket. Depending on the thickness of the sheet, we also talk about strips. Sometimes the term membrane is also used.

The laminar packing deflects the water. With a thermal insulation, freezing of water is avoided at the same time.

The laminar packing consists of laminar strips. The laminar strips are placed overlapping in the rock excavation area so that the edges of the sheets can then be welded together. During welding, a double seam is preferably produced. Two welding seams are arranged side by side. Compressed air can be applied to the intermediate space. With the closed intermediate space, a sufficient waterproofing effect can be started when the pressure drop in the intermediate space does not exceed certain limits for a certain period of time.

The fixation of the sheet occurs in different ways. In the case of reduced resistance requirements, a sheet fixation with a plastic fixing element made as a washer has been imposed in the past. The washer is driven into or fired on the rock or a first layer of sprayed concrete applied. This type of washer is represented and described in document DE2400866. In case of firing, the washers are not fixed to the rock by means of a hammer or the like, but rather are introduced by means of an explosive cartridge into the rock or into the first layer of sprayed concrete applied.

Known washers are represented and described, for example, in documents DE-3244000C1, DE4100902A1, DE19519595A1, DE8632994.4U1, DE8701969.8U1, DE20217044U1. Known washers have been welded with the blade. These washers are represented and described, for example, in DE2833148. The known sheet is also provided, on the inner side of the tunnel, with a nonwoven material of irregular fibers. In the non-woven material of irregular fibers a concrete layer must penetrate the inner side of the tunnel, so that the sheet is not only fixed in the concrete on the washers, but also additionally through the layer of non-woven material. In this way the joint between the washers and the sheet is discharged.

As especially advantageous, the washers with a controlled breaking point were considered. The washers must break in case of a load applied to the sheet at the controlled breakage point. The resistance of the controlled breaking point is essentially lower than the resistance of the sheet. For this reason, the washer is broken first when excessive traction is exerted on the sheet. That is, the laminar joint remains intact in case of excessive traction in it, while the washer breaks.

However, plastic washers are only appropriate if reduced forces occur in fixing the sheets and in a subsequent application of shotcrete.

Document US5851580 shows and describes a device for the projection of concrete in the tunnel.

Especially in the tunnels high forces occur. In rail tunnels, passing trains generate extreme air pressure and, subsequently, an extreme aspiration shot. The pressures act on extremely large surfaces, so that total pressures are produced that require a sufficiently firm bond between the tunnel and rock entibación. The pressures depend on the speed of the trains. High-speed trains increase pressures by a multiple compared to normal trains.

Something similar happens in the case of car tunnels.

With a request like this, steel washers have been imposed as fasteners, which are retained with anchors in the rock.

Known washers have a diameter of approximately 150 mm and a thickness of 3 to 4 millimeters. These washers offer great resistance.

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Known anchors have a diameter of 12 or 14 or 16 or 20 mm. They are preferably made of stainless steel and profiled on the side of the rock to deploy a great resistance to extraction in the rock. For the anchors, corresponding holes are made in the rock. The anchors are then fixed with a mounting cement or other appropriate mounting means in the perforations. Unlike the known nail construction, these anchors can absorb really large forces. Loads are introduced into the rock. For this reason it is possible to build a tunnel tunnel with these anchors capable of withstanding the loads of trains and cars that pass.

At the free end, the anchors are generally provided with a thread, preferably, according to the diameter, of a metric thread M12 or M14 or M16 or M20. At the end of the thread side the steel washers are retained between two screws. The screws allow adjustment of the washers in the anchor.

Normally the anchors are so long that they protrude from the steel washers and penetrate the tunnel. This serves to fix a wire grid as a retaining element during the projection of the concrete and to reinforce the tunneling of the tunnel by joining the rock.

When projecting concrete against the sheet there is a risk that the sheet will reject the concrete or that the concrete will not adhere to the sheet. In this case it is convenient to arrange, at a distance from the sheet, a wire grid or the like to prevent the concrete from falling.

The wire rack also serves to assemble the shotcrete layer.

A spacer for the wire rack can also be mounted on the anchor. Known spacers feature star-shaped rods to support the wire rack on the largest possible surface.

In the known construction form, the anchors cross the sheet. The blade is held between the steel washers. One of the two washers is located on the outer side of the laminar joint, and the other washer on the inner side of the laminar joint.

In practice it has been proven that water flows along the anchors. Therefore, the anchors and washers are subject to the corresponding water request. EP 1950375 is based on the knowledge that water penetrates the helical thread of washers and anchors. Water also passes through the hole created in the sheet. Leakage occurs. Over time, even a leak in the form of drops results in considerable amounts of water. Water can flow from the inside of the tunnel. In winter the water that penetrates freezes. Icicles are formed that fall, at the latest, when the thaw arrives, causing a serious risk of accidents. The ice can also cause considerable damage to the tunnel tunnel.

To avoid the penetration of water in the rock of the washer it is known to insert a rubber ring into the passage hole of the washer. In any case, the rubber ring only has a very limited effect since it cannot enter sufficiently into the screw thread anchors. It is known to provide the rubber ring by the side of the button thread so that they penetrate better between the thread passages than a plain ring. However, this does not achieve sufficient waterproofing.

For the rest, the method of providing the tunnel inside with insulation is known to prevent the formation of ice.

The invention has set forth the objective of improving tunnel tunneling, especially by means of a better sheet. According to the invention, this is achieved with the features of the claims.

As explained before, the sheet is composed of different laminar strips.

The different laminar strips are traditionally placed on the perimeter of the tunnel. The number of anchors and fasteners depends on their distance. It is advantageous that all external fasteners are prepared in the manner described.

Then the prepared laminar strip is placed. You start, for example, on one side of the tunnel at the base. The sheet is carried up the tunnel side. When the blade touches a pin of the outer fixing element, the pin is marked on the sheet and the pin on the sheet can be noticed. This can be used to cut holes in the blade exactly at these points. The cutting can be done by hand or mechanized. As soon as there is a hole in the blade, it can move over the spike.

Preferably, a fixation of the sheet is provided immediately in the spike in question. A gasket is optionally provided on the sheet, then pushing the inner fastener onto the spike. Then the two fasteners are fastened. They curl up. Preferably, the screw is produced by means of a nut on the spike, which has the corresponding thread.

According to the invention, the gasket and the sheet are not mechanically overloaded in the fastening of the fasteners, while creating an anchor construction that exhibits optimum resistance. This is especially achieved by means of spacers between the fasteners. Rings are preferably used as spacers.

The circumstances are similar when the fixing element is alternately placed without a seal on the spike and pressed against the sheet.

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The length of the spike depends on the perimeter of the projected concrete shoring. The shoring can be exclusively concrete. The shoring can also contain an insulating layer. The insulating layer is preferably arranged on the side of the rock, behind the concrete.

In this case, the spike must pass through the insulating layer to support the wire grid described above and the spacer at the front end.

In all the problems of waterproofing, the difference between the external water load, the internal water load as well as the water loads that act both from the outside and from the inside on the projection of projected concrete. Countermeasures are frequently used laminar joints. The laminar joint can be inserted on both sides in the shotcrete. It can also be arranged on one side. The laminar joint can be arranged on the outside in front of the shotcrete to serve as a waterproofing element against water ingress. The laminar joint can also be arranged inside in front of the shotcrete, to prevent the exit of sewage or other liquids inside.

The shotcrete can be applied in one or several layers.

A frequent application occurs in underground spaces within solid rocks. It can be tunnels, warehouses, shelters, canals and other similar constructions. On the ground it is frequently used in open excavations.

The underground application has two different variants:

According to document DE-3244000 C, for example, a first layer of concrete projected on the area of excavated rock is applied. The first layer of shotcrete is primarily used to seal the excavation area. A laminated joint is arranged on the first layer of shotcrete. For the first shotcrete layer, a relatively small layer thickness is sufficient in most cases. The placement of the laminar joint normally occurs in strips that have to be fixed in the rock or in the shotcrete layer. The strips are placed successively so that the edges overlap and complement each other to achieve the desired waterproofing. Welding of the strips is provided on the overlapping edges. In order to fix the strips, it is expected that an anchor will be introduced into the rock first. The anchors can pierce the laminar joint, if the outlets are waterproofed later. This can be done with the help of two flanges of which at least one is responsible for waterproofing together with the sheet, for example by configuring the flange in the form of a neoprene disc. The flanges must fix the sheet together. Of these two flanges, the one on the side of the rock is preferably fixedly arranged, while the other flange is adjustable. The anchors constitute the union to the rock and hold the reinforcement of the concrete with the retained material of the shotcrete, which allows and stabilizes the interior shoring of shotcrete. The concrete reinforcement is usually made of steel, for example in the form of steel trellises. The projected concrete retention material consists, according to DE-3244000, in a wire grid. The wire grid is arranged at a certain distance from the sheet and must prevent the shotcrete from being relaunched by the sheet joint.

In other applications, the laminar joint is expected to be mounted at a distance from the rock. This is done with the anchors described, in which the laminar joint is fixed. However, the problem of rejection of shotcrete is even greater than in the variant described above. The wire net also helps in this case, so that with the wire net technique described, the shoring of shotcrete can be perfectly constructed at a distance in front of the rock excavation area.

In a modified variant of the distance arrangement of the laminar joint, a grid or wire lattice is provided between the shoring and the area of excavated rock. The wire lattice preferably serves as protection against the impact of rock pebbles.

By the magazine “Forschung + Praxis”, 1970, p. 184, the method of extending the wire net directly against the laminar joint is known. During the projection of the concrete, a distance between the wire net and the sheet is certainly produced, since the sheet is dented very differently from that of the wire net.

From DE-2400866A1 and DE-36526980A1, the method of covering the laminar joint on the side of the shotcrete with a nonwoven fiber material is known. The nonwoven fiber material can fulfill different functions. According to DE-3626980, the nonwoven fiber material has different functions, in particular a protection function and a drainage function. According to DE-2400866, it is also provided that the non-woven fiber material is first provided with a primer before the application of the shotcrete itself occurs.

From DE-3741699 the use of laminar joints with a button structure is known. The buttons must keep a distance through which the water that comes out of the rock can escape.

From DE-3823898 the use of the button structure in a laminar joint is known for other purposes, in particular the retention of the shotcrete.

According to the invention, a special configuration of the laminar joint is provided.

The minimum stiffness is represented by an unfoamed sheet of olefins, especially with a polyolefin sheet, for example a polyethylene sheet (PE sheet). Copolymers can also be used, for example

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ethylene copolymer sheets. Each PE is suitable as a waterproofing sheet. They include LDPE, HDPE.

Polypropylenes (PP) are also appropriate.

The stiffness is obtained with a minimum thickness of 1.5 mm, preferably a minimum thickness of 1.8 mm. In other sheet materials the thickness increases until reaching the same minimum stiffness.

The surface roughness is produced by applying particles of the same material as the sheet on the surface of the projected concrete side of the sheet. The particles may have different shapes. An elongated shape is considered advantageous. To do this, a thread or string shape is needed. Before application, the material can be melted slightly so that the material is adhered after contact with the surface of the sheet. In the core the material should not melt. Initial melting requires a surface temperature higher than the melting temperature of the respective material. The temperature of the material used for the initial melting must be still somewhat higher for heating to occur shortly.

The heating necessary for the melting of the surface can be applied to the material with an open flame or otherwise. Plastic particles are manufactured, for example, by grinding a granulate from 2 to 8 mm to a diameter of 2 mm, preferably to a diameter of 1.5 mm and especially preferably to a diameter of 0.2 to 1 mm . The amount applied is measured by the weight per square meter of the application. Calculations according to the weight per square meter of the application are also used in the tissues. According to the invention, a minimum application of at least 20 grams per square meter is preferably provided, preferably an application of at least 50 grams per square meter, especially an application of 100 grams per square meter. In practice, application quantities of 500 grams per square meter and more can be found. Different details and variations in relation to the application of particles are described in the following printed reports:

AT 194605, CH332229, DE4207210A1, DE19718035C, EP901408A or in WO 97/37772 or PTC / US 97/05029, US 9287104, US 5612081, US5075135, US 3622422, US 2936814.

Document DE19718035 also shows a plate or sheet with a rough surface. The roughness occurs with particles applied to adhere to the surface. The particles are intended to have the same structure as the sheet material to be produced by crushing a granulate with an initial size of 2 to 8 mm to 0.2 to 1 mm. The particles initially melt and spread on the sheet. The sheet must be used, for example, for the waterproofing of deposits.

US5728424 shows a geomembrane with particles welded by one of the faces of the membrane. The particles are initially melted as in DE19718035 and spread on the membrane.

Document DE4207210 shows a method for increasing the surface roughness of thermoplastic materials in which the surface is heated to softening and the particles are pressed under the surface.

Optionally the surface of the sheet is further preheated for the application of the material, in order to achieve a better bond between the particles and the surface of the sheet. This preheating can be dispensed with if the heat of production of the sheet is used.

The usual manufacturing of the sheet starts from an extrusion of the material. The pasty plastic is introduced by means of an extruder, through a nozzle, into the opening of a pair of cylinders.

The plastic entered in the interliners can already be sheet-shaped. This sheet shape is achieved by means of a wide groove nozzle. The nozzle groove has a corresponding length and a corresponding width.

Optionally, the pasty plastic is introduced into the inter-cylinders in the form of granules or shavings, whereby a mass of plastic is formed there that is continuously passing through the inter-cylinders so that a sheet is formed between the cylinders.

Between the cylinders of the pair of cylinders, where appropriate also in one or several subsequent laminating processes, the sheet is given the exact desired thickness.

In the first rolling process the exact width of the sheet is not important. However, thanks to the laminate, a sheet edge is produced that takes on the shape of a snake. For this reason, the sheet is cut laterally at the end of the rolling process. The trimmed edge strips are preferably redirected to the extruder, where they are converted back into pasty material for the rolling process. During the rolling process the sheet has a considerable temperature. This temperature is optionally used for the application of particles intended to perch the surface.

Optionally further heating is provided to improve the bond between the particles and the surface of the sheet. Optionally, the particles are pressed with the pressure of the cylinders against the surface of the sheet so that there is a better bond between the particles and the surface of the sheet.

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EP901408A starts from the basis that the welding factor of the junction between the particles and the surface of the sheet is considerably less than 1. This is considered as an advantage so that the particles can be detached again under a corresponding load without destruction of the laminar joint occurs.

Heat can also be applied to particles by simple hot gases. In this case it is possible to dose the particles that are introduced into the hot gas stream. The initial melting measure determines the permanence of the hot gas. The permanence depends on the path of the particles until they collide with the surface of the sheet and the speed of the gas.

The heat can also be applied as simple radiation, for which the particles fall through a heating channel and melt on its surface during the fall due to radiant heat.

The traditional manufacturing of the sheet starts from an extrusion of the material. The pasty plastic is introduced, by means of an extruder and through a nozzle, into the groove of a pair of cylinders.

The plastic that enters the inter-cylinders can already have the form of a sheet. This sheet shape is achieved by means of a wide groove nozzle. The nozzle groove has a corresponding length and a corresponding width.

Optionally, the pasty plastic is introduced into the inter-cylinders in the form of granules or shavings, whereby a mass of plastic is formed there that is continuously passing through the inter-cylinders so that a sheet is formed between the cylinders.

Between the cylinders of the pair of cylinders, where appropriate also in one or several subsequent laminating processes, the sheet is given the exact desired thickness.

In the first rolling process the exact width of the sheet is not important. However, thanks to the laminate, a sheet edge is produced that takes on the shape of a snake. For this reason, the sheet is cut laterally at the end of the rolling process. The trimmed edge strips are preferably redirected to the extruder, where they are converted back into pasty material for the rolling process. During the rolling process the sheet has a considerable temperature.

Optionally, a profile is created as described in document DE19721799.

The more rigid the bending is the laminar joint, the easier it is to apply the shotcrete. The stiffness is determined, on the one hand, by the thickness of the sheet. On the other hand, the stiffness depends on the placement of the laminar joint. The higher the number of fixing points uniformly distributed in the laminar joint, the greater the rigidity. The distribution is preferably chosen so that four adjacent fixing points form the corners of a square. The edge length of the square is equal to the distance of two adjacent fixing points. The smaller the distance of the fixing points or the length of edges of the square, the higher the number of fixing points. With a sheet thickness of 2 mm, a distance of 1.2 m is preferably provided between adjacent fixing points. The distance must be a maximum of 15%, preferably a maximum of 7.5%. The next fixing points are the adjacent fixing points.

The allowed distance may vary by changing the position of the fixing points. In this case, its distance is reduced to at least one construction with the same stiffness as that achieved in case of a distribution of the fixing points in the corners of a square.

With larger sheet thicknesses the allowed distance between adjacent fixing points increases. The distance between the adjacent fixing points is only increased to the extent and / or the position of the fixing points is modified as much as necessary to achieve the required construction stiffness again, despite the greater thickness of the sheet.

With a sheet thickness of less than 2 mm, the allowed distance between adjacent fixing points is reduced. The distance between the adjacent fixing points is reduced to the extent and / or the position of the fixing points is equalized to the extent necessary to achieve the required construction stiffness again, despite the lower thickness of the sheet.

The primer of the laminar joint facilitates the structuring of the shoring of shotcrete.

The use according to the invention of the primer contributes to the structuring of the surface described above and also to the adhesion of the shotcrete to the laminar joint and the protective mesh. The primer layer can be of the same cement or adhesive or binder that is also used for the shotcrete, but without the additives provided in the shotcrete.

The cement / adhesive / binder is used in powder form and mixed, before application on the surface of the sheet, with water and sprayed or sprayed together with the cement powder / adhesive / binder in fog shape Optionally, a special primer in the form of a synthetic adhesive is also used, adding a mineral part to the mixture. The mineral mixture parts of the adhesive also offer better adhesion of the shotcrete.

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The mist-like spray of the primer leads to a thin layer wetting of the sheet surface. The thickness of the wetting layer is adjusted so that the primer does not drain due to its own weight. In practice, the amount to be applied is reduced until no runoff is observed. With a constant output speed of the primer of the application nozzle, the amount to be applied depends on the speed at which the application nozzle moves. If the application is to be reduced, the speed at which the nozzle moves along the application surface can be increased, in this case along the laminar joint.

In case of repeated spraying of the laminar joint in the same area, the respective application can be reduced by reducing the number of repeated applications.

Optionally, water absorbing materials are provided in the primer.

After priming, the shotcrete can be applied in one or several layers on the sheet joint. It is convenient that the shotcrete layer be applied in layers, starting from the bottom. This is achieved by a reciprocating movement of the tool for the application of the shotcrete. As projected concrete or concrete and additives as well as reinforcements and as useful, those described, for example, in the following printed reports are considered:

DE69910173T2,

DE69418316T2,

DE69006589T2,

DE29818934U1,

DE19854476A1,

DE19746958C1,

DE69801995T2,

DE69407418T2,

DE60010252T2,

DE29724212U1,

DE19851913A1,

DE69721121T2,

DE69403183T2,

DE60001390T2,

DE29718950U1,

DE19838710C2,

DE69718705T2.

DE69122267T2

DE29825081U1,

DE29710362U1

DE19819660A1

DE19733029C2, DE19652811A1, DE19650330A1.

DE69701890T2

DE69118723T2

DE29824292U1

DE29812769U1

DE19819148C1

Various embodiments of the invention are represented in the drawing.

DE69700205T2,

DE69010067T2,

DE29824278U1,

DE19854476C2,

DE19754446A1,

Figure 1 shows an excavation of rock 1 in solid rock. Anchors have been introduced at regular distances in the rock. To this end, the corresponding holes have been drilled, fixing the anchors with mounting cement therein. The central axes 2 are illustrated from the anchors.

Rock excavation 1 is used for the construction of a tunnel. For the drainage of the water that comes out and as a protection against falling stones, a projected concrete shoring is foreseen in the rock excavation.

The shoring of shotcrete consists, roughly, of a layer of sheet 4 and a layer of shotcrete 3. The sheet layer 4 is composed of different strips that are placed overlapping and welded together by the overlapping edges. Two welding seams are provided at a distance located next to each other. Compressed air is applied to the hollow space between the weld seams to check the tightness of the weld seams.

The details of the projected concrete shoring are shown in Figure 2.

An anchor 5 is schematically depicted. The anchor 5 is joined by the end that comes out of the rock to a fixing element 14. The sheet 4 is fitted to the fixing element 14.

On the side of the sheet layer opposite the fixing element 14 is a fixing element 15. The fixing elements 14 and 15 hold the sheet layer 4 together.

The fixing elements are also provided with a spacer 13 for a wire lattice 12. The wire lattice 12 serves two functions. It is used for structuring the shotcrete layer 3, preventing the fall of the concrete that bounces off the sheet. The wire lattice 12 also constitutes a reinforcement for the projected concrete layer.

In the shoring of shotcrete, the shoring has, with respect to the form, such importance that the shoring would collapse before reaching sufficient strength without the anchors. The anchors transmit the weight of the concrete shoring to the rock.

After the setting of the projected concrete shoring, the anchors create a firm bond between the shoring and the rock.

Figure 5 shows a possible honeycomb shape 43 for the wire lattice depicted in Figure 2.

Figure 4 shows a spacer 40 for positioning the wire lattice. The spacer 40 is pressed with another nut against the nut 25. The spacer 40 has various arms in which the wire lattice 43 can be engaged.

Figure 6 shows a sheet suitable for the shoring of shotcrete. The sheet 110 has a thickness of 2 mm, with strings of material having been scattered thereon; The strings of material 111 have a wire-shaped structure with a thickness or diameter of 0.1 to 0.3 mm and a length of 5 to 50 mm. The ropes of material 112 have a thickness of 1 to 2 mm and a length of 10 to 30 mm.

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The different material ropes are applied in the exemplary embodiment in separate application processes, in order to be able to heat the ropes of material of larger diameter differently than that of the ropes of material of smaller diameter.

In other embodiments, the material ropes are applied in a common application process.

The material ropes are arranged irregularly over each other, producing in part a hollow positioning of the material ropes. In this position 112 elevations are created with the material ropes up to a height of 3 mm.

The surface of the sheet is partially uncovered.

The scattered material has a weight per square meter of 250 grams per square meter. In other embodiments, there may also be higher or lower weights per square meter. The lower weights per square meter can be produced especially when the sheet surface is further profiled. Thus weights are possible per square meter of, for example, 20 grams per square meter.

The higher weights per square meter are convenient when, depending on the type of concrete projected, application difficulties have to be overcome.

The different strings of material are spread in the embodiment, after surface heating, on the surface-heated sheet 10. The surface heating of the material ropes reaches the fusion.

The heating is produced by radiation, for which the strings of material are extracted by means of a cell wheel sluice of a reserve tank and fall through a heating channel on the sheet that passes slowly below. The heating channel has, in the embodiment, a plurality of electric heating wires and a temperature control system. As a consequence, the temperature of the heating channel can be raised until the strings of falling material have the correct surface temperature.

After the installation of the sheet in the tunnel, in the first example, a fine cement slurry is rapidly projected. The dry cement slurry forms an advantageous primer for a later application of shotcrete. The shotcrete is applied in layers, starting at the tunnel floor. In the exemplary embodiment, the tunnel develops horizontally, whereby the shotcrete is applied in horizontal layers that overlap from the bottom up on the sheet. The layers have a width that corresponds to the desired thickness of the projected concrete layer.

In other embodiments, a smaller width of the layers is envisaged, whereby a first layer of concrete projected onto the sheet is applied first, which completely covers the side of the sheet. Then another sprayed concrete layer is applied that completely covers the abovementioned shotcrete layer. This process is repeated until the desired thickness of the shotcrete layer is reached.

After the creation of the projected concrete layer, the anchors still protrude from the concrete layer. On the protruding ends, cladding plates, especially fire protection plates, must be fixed. The plates are secured in the exemplary embodiment with the anchors and nuts as well as with washers in the projected concrete shoring. So that the shotcrete does not render the thread of the anchors useless, the thread is protected by caps during the application of the shotcrete.

Claims (12)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 55 1. Entibación in civil engineering works, especially tunneling for tunnels or entibación for galleries in solid rock (1), with a waterproofing (5) in the form of sheet against water, using anchors (2) that are introduced in the solid rock (1), the sheet being retained by means of fixing elements (14, 15) in the anchors, the sheet being held respectively between two fixing elements (14, 15), one of which is arranged on the outer face of the sheet and the other by the inner face of the sheet, the outer fixing element (14) presenting an attachment to the anchor (2) and a projected concrete layer (3) being structured on the sheet, characterized by the use of a sheet (11 ) with a rough surface, the roughness being provided on the side of the shotcrete and forming it by applying plastic particles, the plastic particles having a diameter of 0.1 to 2 mm, melting the parts plastic particles on the surface and then spreading or applying them on the side of the side of the concrete shot of the sheet to adhere there. 2. Entibación according to claim 1, wherein a) in the rock excavation a plurality of anchors for the sheet (11) are arranged, which in a sheet (11) 2 mm thick present, with respect to the following adjacent anchors, a distance of 1.2 m or a maximum difference of 15% from 1.2 m, reducing the distance of the anchors in a sheet (11) of smaller thickness until the sheet (11) has the same stiffness as a sheet (11) 2 mm thick with an anchor distance of 1.2 m plus / minus 15% and increasing the distance of the anchors by a sheet (11) thicker, at most, until the sheet (11) has the same stiffness as a sheet (11) 2 mm thick with an anchor distance of 1.2 m plus or minus 15%, and the distance of the fixing points, at most, until the sheet has the same stiffness as a 2 mm thick sheet with a distance of fixing points of 1.2 m plus or minus 15%. 3. Shoring according to claim 2, characterized in that the plastic particles fall during the application of the particles freely through a heating channel or are heated with a flame. 4. Shoring according to claim 3, characterized in that the plastic particles are introduced during the application of the particles in a stream of hot gas and that the plastic particles are released with the stream of hot gas against the face of the sheet . 5. Shoring according to claim 3 or 4, characterized in that a fixed arrangement is used for heating the plastic particles and that the sheet (11) moves past the side of the device. 6. Shoring according to claim 5, characterized in that the side of the sheet on the side of the shotcrete is heated before and / or after application of the particles. 7. Shoring according to one of claims 1 to 6, characterized in that the strings of material of different diameter are heated and applied separately. 8. Shoring according to claim 7 or 8, characterized in that ropes of material (111) having a wire-like structure, a diameter of 0.1 to 0.3 mm and a length of 5 to 50 mm, are used, and strings of material (112) with a diameter of 1 to 2 mm and a length of 10 to 30 mm. 9. Shoring according to claim 7 or 8, characterized in that the strings of material overlap irregularly. 10. Shoring according to one of claims 1 to 9, characterized in that an application of material with a weight per square meter of at least 20 grams per square meter is created, preferably at least 50 grams per square meter and with special preference of at least 100 grams per square meter. 11. Shoring according to one of claims 1 to 10, characterized in that not only the horizontal shotcrete layers are superimposed in layers, but also several layers are applied to each other with respect to the surface of the sheet. 12. Entibación according to one of claims 1 to 11, characterized by a primer of the sheet (11) by the surface of the projected concrete side, the primer being composed of water and the same cement or adhesive or binder provided in the concrete projected.