DE1922118A1 - Process for building tunnels and galleries, as well as a device for carrying out the process - Google Patents

Description

Procedure for building tunnels and galleries and device for carrying out the method

The invention "relates to a method for building tunnels and tunnels with the help of panel-shaped building elements that form a permanent formwork, which are backfilled with concrete and provided with concrete on the side facing the tunnel with a sealing compound to be covered.

In concrete, it is known to use _s lost casings which consist essentially of a backbone of more or less heavy supporting members and secured therebetween bars, wire meshes or through panels. "

Panel-shaped components have also already been proposed which are designed in the manner of elongated rectangles and have bends arranged in rows parallel to the long sides of the rectangle and the lungs become lost shells let join together.

When building tunnels and galleries, however, this results in ^ due to conditions deviating from normal concrete construction, such as the rock pressure, which in its effect to a large extent of depends on the nature of the surrounding rock must be grounded.

In a known method for expanding underground cavities, in particular tunnels, the walls of the Cavity initially by a weak concrete support that gives way to rock pressure and has the shape of an auxiliary vault, be supported.

009841/0989

If the mountain pressure subsides, the final expansion will be by attaching a pressure-resistant lining to the inner surface of the resilient expansion applied first *, Here, a shaping of the flexible expansion is accepted, which, if it exceeds a "certain level, makes it impossible to produce the final tunnel with the desired clear cross-section.

The invention is based on the knowledge that the ideal case of tunneling consists in _s that the concrete vault is created at the same time as the excavation of the tunnel profile ο In every mountain range, except in floating sand,
Where the water pressure is decisive, an underground cavity can remain open for a certain period of time without the need for support, ie without any noticeable rock pressure occurring and requiring an extension. «" The relaxation zones around the cavity form gradually and gradually progress into the interior of the mountain, as the pressure needs some time to develop, because the plastic deformations of the mountain range of the sails only arise some time after the expansion has taken place .

The object of the invention is therefore to propose a method with which it is possible to produce a concrete lining of the required thickness in this relatively short period of time before the occurrence of the rock pressure, in order in this way to create a
to enable significantly faster and more economical tunneling. ..

This object is achieved by the invention in that Mpiitagsbogen van I profile, which with their outer contour is about the clear The cross-section of the developed tunnel or adit, after the pile has been fired and loaded, installed right up to the jacking joint,

009841/0989

with the cavity to be concreted at the front by 'a front formwork is completed, and that, following the "already concreted tunnel section -and from the bottom to Progressive tunnel apex, the tabular ones. Components placed on the assembly arch and with concrete, which is preferably vibrated, up to the tunnel log! backfilled will. In this way it is possible to produce an expansion that immediately occurs when the mountain pressure occurs has sufficient strength, so that the gate drive is extraordinary can be done quickly. Experience has shown that the G-ebirgsdruck actually only then has an effect when the freshly placed concrete lining has been produced and has assumed the required load-bearing capacity. the Minimum downtime that can be expected in every rock and within which the expansion must be carried out, is easily undercut when introducing the 'expansion.

Attempts have been made in recent years to use the steel structure that was customary up to that point, in particular with Road construction to be replaced by ring expansion. This construction with steel arches or lattice girders, wire mesh and Shotcrete has proven itself in practice, but is not economically justifiable.

In contrast, the method according to the invention allows a concrete structure that is adapted to the mountains and vibrates heavily on the eruption profile and a further destruction of the mountains by foreign influences, in particular air and Water, prevents producing. The expansion, which is viable immediately after installation, distributes the pressure of the less viable Rock on more stable rock layers and thereby secures the danger zone immediately behind the Propulsion.

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In doing so, they act as formwork and reinforcement at the same time serving panel-shaped components, which are supported by the assembly • arc supported, a tearing off of the concrete shell during the vibrations occurring during blasting, so that a Disadvantage that adheres to the shotcrete protection is eliminated.

The method according to the invention thus allows a concrete supporting structure to be created in a single operation in the building itself, the rock pressures occurring from a homogeneous structure 3? els-Beton-Sehalung and reinforcement can be taken up by the assembly arches without impairing the tunneling work. In addition, the Formwork and reinforcement serving panel-shaped components are designed so that a solid association between the concrete and a sealing compound sprayed onto the surface facing the tunnel.

In order to achieve a continuous, secure bond between the concreting sections to be made one after the other, according to a further proposal of the invention, the concrete is placed in such a way that that the ends of the panel-shaped structural elements lying at the front in the advance direction remain uncovered and that the Newly installed components at their rear ends with those protruding beyond the finished concreting front ends of the previously installed components are connected. .

A particularly simple closure of the cavity to be concreted to the drive front results when the foremost panel-shaped component with a free overlap attached to the previous component already installed and the freely overlapping part is placed against the tunnel wall delimiting the excavation.

009841/0989

When the tunnel is driven into rocky rock and a Securing the tunnel joints and the tunnel slope "until immediately is required on the face of the drive, the panel-shaped components can be on the tunnel side Splash the I-mounting arch placed and between the outside, lying flanges and the rock surrounding the tunnel excavation provide a flat, temporary and movable support for the rock to be installed.

The cavity to be concreted between the formwork reinforcement and the breakout is expediently closed at the front by that one attaches a front formwork to the mounting arch delimiting the cavity to be concreted at the front, the outer contour of which essentially corresponds to the breakout profile.

The front formwork can consist of a box-shaped gate protrusion arranged on one front side of the I-arch, the in cross section, starting from the outer arch flange, protrudes to the outside in the shape of a roof and at a distance from the inside which allows the insertion of a component Bend flange connects to the web of the I-bend.

It is advisable to use the assembly arch provided with the front formwork a nozzle for pressing concrete into the upper part of the cavity to be concreted. When using a Flat, temporary and movable support when driving in pressurized rock are expediently elongated plate-shaped lances two to three times the length of the Arc spacing used, which on their long sides with interlocking ! Guides are provided and adjacent lances are angled around a longitudinal axis as well as a limited deviation allow from the longitudinal direction.

0098A1 / 0 98 9

A cheap and appropriate training of each other leading lances arises when each on a longitudinal edge the lance in from the edge. through a longitudinal slot accessible duct and as the open at both ends other longitudinal edge with play in the adjacent ElOrrnngskanal engaging, in cross-section T-shaped slider is arranged. On the side flares facing the tunnel of the Lances can be provided tooth-like ribs with which a device for advancing the lance releasably engages bring is. So that the lances that come into contact with a part Length are always in the concrete, do not connect to it, -φ they are advantageously made of steel and the outer surfaces are ground. The lances are also equipped with a tip, which is conical on the side facing the tunnel.

The device for moving the lances forward can consist of a pressure cylinder consist of a claw on the extending piston rod for engaging the tooth-like ribs on the Has lances and the cylinder can be supported on the side surface of an assembly bow.

The invention is explained in more detail with reference to the drawings.

It shows:

1 shows a longitudinal section through a tunnel that is being driven,

Ji ¹ Ig. 2 a partly in section and partly

a representation of a tunnel lining that appears in the front view,

1 ' ¹ Ig. 3 a section through i'ig. 2 on. the line IH-III

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Pig. 4 one of the pig. 3 corresponding section through a concreting section final face formwork,

Pig. ' 5 the arrangement according to Pig. 4 for backfilling the formwork with gravel,

S ¹ Ig. 6 another opportunity to make a forehead formwork,

Pig. 7. a partial side view of an assembly sheet to be used in tunnel construction, μ

Pig. 8 shows a longitudinal section through a tunnel that is being expanded, with lances leading to the Support of the pressurized rock can be used,

Pig. 9 is a partially sectioned representation appearing partially in the front view a tunnel extension to Pig. 8th,

Pig.1o a section through Pig. 9 on the line X-X on a reduced scale,

Pig.11- one of the Pig. 1o corresponding sectional view Another embodiment example for a face formwork when using lances,

Pig. 12 a section through the goal pebbles lying next to each other,

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• Pig. 13 a Yorschublanze in plan view and 14 shows a Yorschu lance in side view.

In Ifig. 1 is the iDunnel or in the process of being driven Stud labeled 1. The front end of the drive, the so-called face face, from which the next drilling and another tee shot will be won is indicated at 2. Up in the immediate vicinity the face face 2, assembly arches 3 are set up at suitable distances from one another in the iDunnel. The assembly sheets 3 correspond in its outer contour essentially the clear cross-section of the finished tunnel. The front moaita arch 4, which has an outer profile approximately corresponding to the excavation of the tunnel, is explained in more detail later with one Front formwork 14 provided.

As soon as the assembly sheets 3, 4 have been set according to the profile, panel-shaped components 5 are on the outside the bow hung up. The components 5 form a permanent formwork, which also acts as a reinforcement for the finished concrete structure works. The panel-shaped components 5 are in the illustrated embodiment with on both sides, starting from the central plane of the element, directed bends and can be used both on their longitudinal as auh narrow sides brought to overlap each other and be attached to each other. The ends of the structural elements 5 which are located at the rear in relation to the drive direction are connected at the front ends of the structural elements of the already finished concreting 7 in the area 11, so that a firm Yerband results between the successively produced expansion sections. Eerner is at the front of the finished concreting 7 an approximately dovetail-like setback 14a produced, which also has the purpose of a to create a secure yerband for the subsequent new concreting section.

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If the panel-shaped components in the "described Wex'den built in wise, arises between lines and the the rock delimiting the tunnel excavation "a cavity 10, the, the progressing from bottom to top of the installation Elements 5 following, is filled with concrete. The concrete is compacted by vibration. To fill out the Located in the head of the tunnel, last remaining cavity is concrete through a nozzle 24, which is through the Front formwork 14 passes through, pressed in. A hose from a suitable concrete pump is used for this purpose attached to the connecting piece 24.

As can be seen from the Yors' view, the up to un- ^

Any extension brought indirectly to the jacking face, even with concrete that has not yet hardened, is reliable and Resistant support of the tunnel, which is already installed before the rock pressure takes effect. The installation does not affect the drilling work on the jacking face 2. The one from assembly arches, structural elements and concrete underfill existing arrangement is so resistant that it can withstand explosive vibrations.

In iig. 1 shows the expansion produced by the method according to the invention in a schematically simplified manner. For normally used rock, the following procedure is used in practical operation about λ:

After completing the blasting and loading work, two assembly sheets are required Stekked according to the profile and provided with distance iron (not shown in the drawing). On this arch the panel-shaped components are on both sides from below to the top, assembled piece by piece to form a ring and at the same time backfilled with concrete ■ "which is compacted by vibration. The front formwork 14 ensures a clean processing of the concrete.

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When driving the first few meters of a tunnel, a quick-release binder "can be added to the concrete so that it can be used again immediately the blasting and drilling operations can continue. As soon as a sufficient safety zone has been created inside the mountain the quick-tie attachment can be omitted. The other assembly bows are made at intervals, depending on the rock pressure set from 1-2 meters. Larger distances between the arches are not recommended for economic reasons, otherwise panel-shaped structural elements of considerable thickness would have to be used.

When driving a tunnel in normal rock, for example, 21 Morfca bends can be used. This then results in a continuously supported tunnel section of 20 meters, in which the expansion withstands all vibrations during blasting until the concrete shell has set. After a tunnel section of this type has been created, the assembly arches are always removed at the back and reinstalled at the front.

If the rock allows it, the extension can be up to 10 - 12 m stay behind the tunnel breast and through a second Working group. The assembly arches must, however, be installed immediately behind the heading and wedged so that a lateral displacement by the explosive effect is impossible. The mounting sheets that come with have the illustrated embodiment I-profile dimensioned so that they absorb the stresses occurring without deformation and can be used again and again. As soon as the assembly arches in the rear area of the extension have been removed, the surface facing the tunnel should be the panel-shaped components are covered with a sealing compound. The sealing compound is sprayed in the usual way upset. . "..; ...-

BAD ORIGINAL 009 8 A1 / 0989

- "11 -

If the river is driven into very old rock, it is recommended es., the concrete construction with the help of two assembly trolleys as well to carry out the necessary connecting parts. The profile of the arches is determined by the strength of the pressure caused by the mountains certain concrete elements are selected.

laughing at the end of the blasting and loading work, the two of them Mounting arch · set and anchored in accordance with the profile. The assembly takes place as explained above. Also the installation of the tabular Structural elements and the pouring of the concrete take place in the same way as described. The distance between the arches can be 0.6 - 2.0 m.

A quick binder additive for the concrete is to be provided if the concreting in sections takes place at shorter intervals repeated than 10 hours. laugh at the second tee i.e. after the blasting and loading work is complete, the rear arch is removed and in front of the other arch installed again. The panel-shaped construction elements are connected to those already concreted in after they have been placed on the Outer flange of the pre-built arch have been placed. Then concrete is poured in again. The application of the sealing compound should take place at some distance from the gate drive; however, it is also possible to do this work immediately after to carry out the pouring of the milled concrete.

Should the Gebirgsdructrelations permit, can 6-8 mounting sheet used and the. The operation is carried out essentially in the manner described above will.

As a Vox precaution and for general security, if necessary a shotcrete layer before setting up the assembly arch on the whole or only one particularly endangered. Part of the excavated area can be applied.

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In special cases, rock anchors can also be installed for securing before the assembly arches are set.

The expansion according to the invention is in the right part of FIG. 2 before and in the left part of the same figure after concreting shown in section. As can be seen from this, the panel-shaped structural elements are 5 · before concreting on the outer flange 3a of the assembly bow 3. The bends 8 arranged in rows run in the case of the one shown Embodiment transverse to the tunnel axis.

The one located between the rock and the structural elements 5 Cavity 10 is filled with concrete 7. The concrete penetrates into the spaces behind the bends facing the tunnel a. When a sealing layer 9 is applied to the surface on the tunnel side, preferably by spraying has been, the sealant combines with the concrete that it is from the tunnel side in the Gaps in behind the bends facing the rock.

Fig. 3 shows a section through Fig. 2 on the line III-III. This is the connection of the newly pre-built component to the one that was concreted in during the previous work process Element shown. The concreting or tunneling proceeds from right to left in relation to FIG. 3. The components are placed one on top of the other with the adjoining edges in area 11, so that those from the central plane of the elements interlocking with bends directed on both sides. An opening remains free, into which a connecting rod holding the adjacent elements together is inserted. The one in front The end of the component last set in concrete must protrude beyond the end of the concrete in order to be able to make the connection.

009841/0989

BATH

So that the concrete cannot flow out of the cavity located between the structural elements 5 and the rock when concreting, a closure must be made at the front end of a concreting section. An exemplary embodiment for this can be seen from FIG. 4. A further element 5 is connected to the component to be concreted last in the manner explained above, but the overlap of the front over the rear element is chosen so that the front element with the overlapping part 5a is bent up to the rock delimiting the tunnel excavation can. Thus, the then introduced behind the preceding concrete component the conclusion formed by the part 5a is not%

pushes out, a retaining wire 5b between the portion 5a of the front component and the counter-drive direction be attached to the adjoining component.

5 shows an embodiment of the invention in which the structural elements 5 are backfilled with rolling gravel 13, split, filter or cellular concrete instead of concrete. This type of expansion is chosen at those points in the tunnel where drainage is required. The installation of the components is carried out in the same way as described above. A sufficiently thick waterproof layer 9, for example made of shotcrete, is applied to the tunnel side. ä Every 5 - 8 m a dilation joint is provided, which is expediently sealed with a hinged joint tape. The water flowing in from the rock flows through the cavities contained in the gravel and the like to the tunnel floor, where appropriate passage openings are made, which prevent damming and the resulting pressure build-up. If the water behind the structural elements is to be displaced, there is the possibility of pressing cement into the backfill 13.

0 0 9 8 A 1/0 9 8 9

Another possibility to "concretize the cavity on to complete the front end is in! ig. 6 shown. Bs This is an assembly arch that forms a front formwork forms. The front formwork consists of a box-shaped Projection which is attached to the side facing the cavity to be concreted and extends over the entire length of the arch.

consists

The box forming the front formwork / from a wedge-shaped protruding from the outer flange 3a of the arch Part 14 »which is closed by a web 15 parallel to the inner flange 3b of the assembly bow. The bridge 15 has a sufficient distance to insert a component 5 from the flange 3b. This creates a cavity 16, which receives the front end of the component installed last. This end remains when concreting, like Prop. 6 shows free. The wedge-shaped protruding part 14 of the face form results in the face of the finished concreting section a corresponding recess into which the concrete of the next concreting section penetrates, so that an approximately dovetail-like connection is created between the first and then the concrete introduced. As soon as the concrete has solidified sufficiently, it will be in the finished tunnel section in accordance with the tunnel advance dismantled arches were built in front of the building, with the arch delimiting the new concreting section at the front, in turn, a front formwork has and stands with its outer flange 3a close to the tunnel breakout.

In Fig. 7 a connection between two arch parts forming an assembly arch is shown. On the inside Hinge tabs 18a and 18b are attached to flanges 3b of the arch parts.

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BAD ORfGiNAL

Through the overlapping openings in the joint flaps 18a and 18t> a bolt 17 forming the joint is inserted through it and appropriately secured in its position. On the adjoining end faces of the assembly elbow parts transverse flanges 19a and 19b are respectively fastened between the outer flange 3a and the inner flange 3b. These Cross flanges have openings through which a head bolt 20 passes. There is a transverse opening in the bolt shank, which serves to accommodate a wedge 21-. By introducing of the bolt 2o and driving in the wedge 21 results in a rigid connection between the arch parts.

V / hen the tunnel is being driven in pressurized rock and the tunnel walls have to be secured up to the driving face, can in the hand of the prop. 8-14 explained. Like Pig. 8 shows the foremost monta ^ oogen-3 Installed as a guide arch for the tunnel walls securing, hydraulically advanced lances 22. That means, that the outer flanges 3a are at such a distance from the rock surrounding the excavation, that the lances 22 lie tightly against the rock. The web height of the guide arch corresponds to the thickness of the one to be produced Concrete lining.

After the arches have been installed and anchored in accordance with the profile, the lances 22 are attached. Form the lances as will be explained later, a jacket enveloping the tunnel. A pressure cylinder is used to advance 23, which with its extendable piston rod 24 on the to be advanced Attacks lance and is supported with the opposite end of the cylinder on a Pührungsbogen. The pump and the reservoir for the pressure fluid for feeding the cylinder 23 are indicated at 25.

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Pig. 9 shows a representation corresponding approximately to FIG. lung. As it turns out, the tabular ones become Components 5 placed on the inner flanges 3b while the lances 22 are supported on the outer flanges 3a. The cavity between the flanges and components is filled with concrete 7 in the manner explained above. As a result, the lances lie with their rearward ones Ends in concrete.

The arrangement according to FIGS. 8 and 9 is shown again in FIG shown in a section on the line X - X through FIG. The cavity to be concreted is hereby blocks or boards 30 adapted to the arch shape and placed between the lances 22 and the structural elements 5 are arranged.

If an arch corresponding to the figure with front formwork is used, the arrangement shown in FIG. 11 results. The lances are in turn on the outer flanges 3a, the arch 3, while the front end of the structural element 5, which is initially to be kept free from the concrete, enters the cavity 16 the front formwork 14, 15 engages. When moving the Lances a cavity 7a results between the concrete 7 and the rock, into which the concrete is pressed.

The lances 22 are, as FIG. 12 shows, plate-shaped «hollow bodies, which have a length corresponding to two to three times the distance between the sheets 3. One at a time On the narrow side there is a guide 27 which is accessible from the outside through a longitudinal slot 26 and is open at both ends. in which engages a cross-sectionally approximately T-shaped slider 28 attached to the adjacent lance. the Guides 27 and the slots 26 are dimensioned so large relative to the sliders that the lances 22 to the Can adjust tunnel profile (see Fig. 9). At the same time, a certain lateral mobility is guaranteed.

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As can be seen from I ¹ Xg, 13, the lances 22 are provided on the side facing the tunnel with tooth-like ribs 29, on which, according to FIG. 11, the hydraulic cylinder 23 is attached, the end of its extendable piston rod 24 with corresponding claws 31 is provided. As an abutment for the cylinder 23, one of the arches 3, preferably the arch provided with the front formwork and delimiting the last concreted section at the front, is used. The cylinder 23, which according to Pig. 8 is connected to a pressure medium pump, is attached to the lance 22 that is to be advanced. The fact that the lances are advanced individually eliminates the need for an expensive hydraulic installation. The lances are ground smooth on the outside so that the lances are not connected to the concrete. Each lance 22 is equipped with a tip 3o which is concave towards the tunnel side.

The concreting of the respective expansion section can take place, when the lance tip has been advanced about 1 m. the Panel-shaped components are placed on the inner flange 3b of the arch and from the sole in the direction of the JPirst assembled. The concrete is placed between the components and the lances and compacted by shaking. The front formwork guarantees a clean processing of the concrete.

To concrete in the highest part of the behind the building elements To be able to press in the cavity formed is expediently a connection piece on the arch provided with the front formwork arranged to which the hose supplying the concrete under pressure can be connected.

The securing of the tunnel section before the completed expansion by the lances is extremely adaptable and can can be carried out with a few assistants.

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Claims (1)

before Γ1. A method for expanding the tunnel and tunnel with the help of panel-shaped structural elements that form a permanent formwork, which are backfilled with concrete and, if necessary, covered with a sealing compound on the side facing the tunnel, so that the assembly arch (3) from I- Profile, which correspond with their outer contour approximately to the clear cross-section of the developed tunnel (1) or adit, after shooting and loading the pile up directly to the jacking joint (2) are installed, the cavity to be concreted (10) at the front by a End formwork is completed, and that, following the already concreted tunnel section (7) and progressing from the base to the tunnel apex, the panel-shaped structural elements (5) are placed on the assembly arch (3) and covered with concrete (which is preferably vibrated) until Tunnel vertices are backfilled. 2. The method according to claim 1, characterized in that that the "concrete is placed in such a way that the ends (11) of the tabular ones which are at the front in the direction of advance Components (5) remain uncovered and that the newly installed components (5) to your rear lying ends with those protruding over the finished concreting front ends of the previously installed components are connected. 3. The method according to claim 2, d a d u r c h g e k e η η-z e.i c hn e t that the foremost panel-shaped structural element (5) with a free overlap (5a) attached to the already installed preceding component (5) and the free overlapping part (5a) placed at the end of the cavity to be concreted against the tunnel wall delimiting the excavation will. 009841/0989 Method according to patent claims 1-3, characterized in that that the panel-shaped structural elements (5) on the tunnel-side plan (3b) of the I-mounting arch (3) placed and that between the outside plansche (3a) and that surrounding the tunnel excavation Rock a flat, temporary and movable support (22) is installed for the rock. Device for performing the method according to claim 1-4, characterized in that the front formwork (14) on the to be concreted Cavity (10) is attached to the front limiting mounting sheet (3), the outer contour of which is essentially the breakout profile corresponds, with the front formwork consisting of a box-shaped ■ arranged on one front side of an I-bend (3) There is projection (14) which, in cross section, starting from the outer curved flange (3a), is roof-shaped towards the outside protrudes and at a distance (16) from the inner one allowing the insertion of a component (5) Bend flange (3b) connects to the web of the I-bend (3). Device according to claim 5, characterized in that that on the assembly bow (3) provided with the front formwork (14) a connecting piece (24) for pressing in of concrete is arranged in the upper part of the cavity to be concreted (10). Device according to patent claims 5 + 6, characterized in that that the flat supports for the rock are elongated plate-shaped lances (22) from two to three times the length of the arc spacing and on their long sides with interlocking Guides (26, 27, 28,) are provided, which angled adjacent lances (22) about a longitudinal axis and a allow limited deviation from the longitudinal direction. 009841/0989 8. Device according to claim 5-7, characterized in that that in each case on a longitudinal edge of the lance (22) one from the edge through a longitudinal slot (26) accessible guide channel open at both ends (27) and on the other longitudinal edge a cross-section which engages with play in the adjacent guide channel (27) T-shaped slider (28) is arranged. 9. Device according to claim 5-8, characterized in that that on the side surface of the lance (22) facing the tunnel there are tooth-like "ribs (29) are provided with which a device (23, 24) for Moving the lance forward Ij22) is releasably engageable. 10. Device according to claim 5-9, characterized in that that the lance (22) consists of steel and is ground smooth on the outer surfaces. 11. Device according to claim 5-10, characterized in that that the lance (22) is equipped with a tip (30) that faces the tunnel Side is conical. 12. Device according to claim 5- 11, characterized in that that the device for moving the lance (22) forward from a pressure cylinder (23) consists of a claw (31) on the extendable piston rod (24) for engaging the tooth-like ribs (29) on the lance (22) and the cylinder (23) of which can be supported on the side surface of an assembly bow (3). 009841/0989 Blank page