WO1988001679A2

WO1988001679A2 - Process and device for lining and securing a subterranean hollow space opened by the shield-driving method

Info

Publication number: WO1988001679A2
Application number: PCT/DE1987/000402
Authority: WO
Inventors: Jürgen FALTIN
Original assignee: Strabag Bau-Ag
Priority date: 1986-09-05
Filing date: 1987-09-04
Publication date: 1988-03-10
Also published as: DE3630240C2; DE3630240A1; EP0258905A1; WO1988001679A3

Abstract

A process and device for lining a hollow space (10) opened by the shield-driving method. The soil around the shield is converted by high-pressure injection of a cement suspension into a hardening concrete casing that forms the lining of the hollow space, thus allowing a significantly smaller excavation cross-section to be obtained.

Description

Method and device for lining and securing an underground cavity opened in the shield drive

Technical field

The invention relates to a method and a device for lining and securing an underground cavity shown in the shield drive, in which a flowable, hardening mass is injected into the mountains surrounding the cavity.

State of the art

For the lining and securing of tunnels and tunnels driven in the shield drive, prefabricated segments made of reinforced concrete or steel are mostly used, which, according to the shield drive, are installed one after the other in the shield tail shield one after the other. The tubbing must be brought from the surface through the entire tunnel or gallery, which has now been completed, and then first set up and attached to the last tubbing installed. Depending on the tunnel or tunnel cross-section, it is often necessary to assemble the tubbing rings from individual parts on site. In any case, the longitudinal transport of the tubbings through the completed tunnel takes up a lot of space and hinders the removal of the pile detached from the face. In addition, the excavation cross-section must always be slightly larger than the outer circumference of the tunnel lining, so that appropriately large shields are also required. It is also known to produce the tunnel or tunnel lining in in-situ concrete, which is placed in a formwork which limits the inner surface of the tunnel lining and must be stiffened accordingly. The fresh concrete for the tunnel lining can be transported through pipelines, but the excavation cross-section here also depends on the outer circumference of the tunnel lining.

PRESENTATION OF THE INVENTION The object of the invention is to simplify the production of the lining of tunnels and tunnels excavated in shield driving and to reduce the excavation cross section.

This object is achieved with the invention by a method in which the soil surrounding the shield is mixed at least over part of the shield length from the shield in such a thickness with the hardening mass that after hardening it becomes the load-bearing lining of the opened cavity forms.

Such a method has the advantage that the surrounding mountains, in particular uneven soils, such as sand or gravel mixtures, which can also be permeated with larger stones and cohesive constituents, in place in the load-bearing part, namely in the lining of the creating tunnels or tunnels. This not only eliminates considerable material transport for the lining, such as fresh concrete or segments, but also the excavation cross-section is considerably smaller, since the finished tunnel lining is then outside the shield casing and not inside, as is the case with segment lining or in-situ concrete expansion is.

When the hardening mass is introduced into the mountains surrounding the shield, it must be supported by formwork until it hardens, but this narrows the tunnel cross section. did not cut as much as is the case with the transport devices for fresh concrete or prefabricated segmental lining elements.

A cement suspension is expediently used as the hardening mass, to which bentonite can also be added and which is injected under high pressure into the soil surrounding the shield. The introduction of the suspension under high pressure has the effect that the surrounding soil is cut open and moved as if with a knife, whereby it mixes intimately with the injected suspension. In contrast to the known cement or mortar injections, which are intended to fill cracks and crevices in the mountains surrounding the lining, according to the invention, the cement suspension is pressed into the soil surrounding the shield jacket with such high pressure and speed that there is approximately before ¬ hand water cannot be slowly displaced into cavities further away and part of the soil that is displaced by the injected cement suspension must also be removed. For this purpose, excess material is removed from the lining area produced in each case through openings in the shield or in a formwork following it, collected and passed on for days.

The hardening mass is expediently processed for days, conveyed to the shield and passed through it into the surrounding earth.

A device for lining a subterranean cavity opened in the shield drive, which consists of a shield and a formwork adjoining this shield, surrounding the opened cavity or shielding expansion elements and which can be used to carry out the method according to the invention, is by means of devices attached to the shield for injecting a hardening Mass in the soil surrounding the shield, wherein either the injection devices or special devices for mixing this soil with the hardening mass are expediently attached to the outside of the shield. The injection device is expediently a high-pressure injection device for cement suspension, which has injection nozzles for the hardening mass. These can be arranged at least over a part of the length of the shield distributed over the circumference in the shield casing and can be directed at different angles against the earth surrounding the shield casing. In this case, the cement suspension can be pressed continuously into the soil surrounding the tail tail according to the shield advance. It is also possible, however, to work in sections and to suspend with the shield drive when introducing the suspension and

Hold the sign until the pressed cement suspension has set, whereby care must of course be taken that the sign is not concreted, i.e. sticks to the hardening mass.

In order to create space when the hardening mass is introduced into the surrounding earth, openings for the outflow of excess soil and consolidation material are arranged in the shield, which are closed by pressure valve closures. These closures open as soon as the pressure in the soil outside the shield jacket exceeds a predetermined value. They then allow water, soil material and / or cement suspension to enter the interior of the cavity, where these excess amounts are collected and, appropriately separated from the excavated material detached from the face, are conveyed over the course of the day.

In another embodiment of the invention, the injection nozzles are arranged in the walls of injection tubes, which pivot about their longitudinal axes on the outside of the shield jacket, approximately parallel to its generator. are stored in cash. This configuration has the advantage that the working space in the shield is practically not restricted and that a relatively large injection space can be reached in the circumferential direction of the shield from each injection tube. So that the injection tubes do not form any additional resistance when propelling the shield, they are expediently housed in depressions in the shield shell.

In another embodiment of the invention, the injection nozzles can be arranged in a ring arranged on the outside of the shield jacket and rotatable about the longitudinal axis of the shield. It is then sufficient to accommodate relatively few injection nozzles in the ring and to bring the nozzle outlet openings to all parts of the shield circumference by turning the ring in order to achieve a good mortaring of the floor surrounding the shield jacket.

In order to achieve a particularly good mixing of the soil with the cement suspension, a rotatingly driven mixing and milling disk or worm can be arranged on the outer circumference of the shield, the mixing and milling blades of which have a radial extent that corresponds to the desired outer circumference corresponds to the lining and which the injection nozzles for the hardening mass carry. With such a mixing disk or screw, the desired shell thickness of the lining can be exactly maintained.

In another embodiment of the invention, injection lances can be provided which can be moved approximately radially outwards and inwards in the shield casing and which have injection nozzles at their ends which protrude into the surrounding earth. These injection lances are then first pressed from the shield casing into the surrounding earth until they have approximately reached the outer contour of the lining to be produced. Then you inject suspension for injection the nozzles arranged at the end of the injection lances, which sets the surrounding soil in motion and mixes with the earth's masses, while the injection lances are slowly withdrawn again. The openings for the discharge of excess soil and consolidation material surround the injection lances in a ring, so that this excess material can enter the interior of the tunnel along the injection lances and be removed there. In this case, several injection lances are expediently arranged next to one another in the longitudinal direction of the shield such that the lances which are adjacent to the injection jets and which are mixed with the injection mortar, overlap, solidify and overlap, and a coherent lining shell is formed. In this regard, it is noted that the high pressure injection with lances for the production of earth piles or foundation bodies arranged deep in the earth is known per se (brochure "High Pressure Injection HDI" from Karl Bauer Spezialtiefbau GmbH & Co. KG).

The outflow openings for the excess soil material can be connected to an outflow ring line and the injection nozzles can be connected to an inflow ring line in the interior of the shield, which in turn are then connected to a delivery line or to a suspension feed line.

Brief description of the invention

Further features and advantages of the invention result from the following description and the drawings of preferred embodiments of the invention, which are explained in more detail by means of examples. It shows:

1 shows a schematic longitudinal section of a tunnel partially excavated in shield driving with a processing plant for cement suspension arranged above ground and a soil separator plant in a schematic representation, Fig. 2 shows the tunnel of FIG. 1 in a schematic cross-section along line II-II of

Fig. 1

3 shows another embodiment of the tunneling shield for producing the tunnel lining in a partial representation corresponding to FIG. 1,

4 shows the subject of FIG. 3 in a cross section along line IV-IV,

5 shows a third embodiment of the driving shield in a partial view corresponding to FIG. 1,

6 shows the subject of FIG. 5 in a cross section along line VI-VI,

7 shows a fourth embodiment of the driving shield according to the invention in a partial representation corresponding to FIG. 1,

8 shows the subject of FIG. 7 in a cross section along line VIII-VIII,

FIG. 9 shows a fifth embodiment of the driving shield according to the invention in a partial representation corresponding to FIG. 1 and

FIG. 10 shows the subject of FIG. 9 in a cross section along line XX. Ways of Carrying Out the Invention

In FIG. 1, 10 denotes a cavity, for example a tunnel with a circular cross section, which is driven up in rolling mountains 11 in the shield drive, which consists, for example, of coarse gravel-sand mixtures. The tunnel 10 is driven from a shaft 12 in which the feed line 13 and the delivery line 14 for the tunneling, a suspension line 15 for a cement suspension and a return line 16 for water and excess soil material are guided from underground to underground. In front of the face face 17 is the tunneling shield 18, which can be an open shield, a compressed air shield or hydro shield, but also a knife shield. In the exemplary embodiment shown, it has a cutting wheel 19 in the cutting area for loosening the soil material in the area of the working face 17 in full section. The excavated material is slurried with water and conveyed through the conveying line 14 into a separating plant arranged above ground, which is designated 20 in its entirety. There the solids are separated off in a collecting container 21, while the conveying liquid is fed back through the feed line 13 for propulsion to the face 17.

In the interior of the driving shield 18 there are the feed presses 22 for the shield, which are supported towards the rear against the last formwork element 23a of a traveling formwork 23, which is arranged in the tunnel space 10 behind it. The formwork element 23a is overlapped by the shield tail 24, which is sealed at its rear edge with a suitable sealing lamella 25 against the formwork 23. In the area of the shield tail 24 there is an injection device 26 for injecting a hardening mass into the soil 27 surrounding the shield. This I jection device 26 consists of. 1 and 2 of the embodiment of a plurality of injected over the circumference of the shield shell 28 nozzles 30, all of which are connected to an inflow ring line 31 which is located in the interior of the shield 18 and to which the suspension line 15 is connected. The injection nozzles 30 in the shield jacket are arranged radially and obliquely in the direction of advance and obliquely against the direction of advance 32. In the direction of advance in front of and behind these injection nozzles 30 and in the circumferential direction between them there are openings 33 in the shield jacket 28 which are closed by pressure valve closures 34 and through which excess soil and solidification material can flow off into drain ring lines 35 which are connected to the drain line 16 leading to the day. This discharge line 16 leads into a separation container 36, where liquid components are separated and the solid components are conveyed through a line 37 to a suitable landfill.

Above ground there is a processing plant for producing a cement suspension, which is designated 38 in its entirety. The cement is fed from a cement silo 39 via a balance 40 into a mixer 41, into which water is simultaneously added from a container 42 and, if desired, bentonite is also added from a weighing funnel 43 to improve the processability. Cement, water and possibly bentonite are mixed thoroughly in the mixer 41 and pass through a storage container 44 into the suspension line 15, which leads to a high-pressure pump 45. From there, the cement suspension is passed through the high-pressure line 15b into the inflow ring line 31 and from there into the injection nozzles 30, through which the suspension is pressed into the earth space 27 surrounding the shield jacket 28 under high pressure. Here, the pressure generated by the high pressure pump 45 is between 300 and 700 bar. The cement suspension pressed out under this high pressure by the injection nozzles 30 sets the soil surrounding the shield mantle in motion and mixes intensively with it, filling all cavities and the ground water which may be contained in the soil through the outlet openings 33 into the Flux ring lines 35 presses. The cement suspension forms here, together with the rolling soil surrounding the shield casing, a concrete shell, which then hardens and forms the lining of the opened cavity 10, which supports it against the rock pressure. After this lining has hardened, the rearmost formwork element 23b of the formwork 23 can then be removed and brought forward into the area of the shield tail 24 after the shield 18 has been advanced by the length of a formwork element 23a or 23b.

It can be seen from FIG. 2 that the injection nozzles 30 are arranged at such a distance from one another in the circumferential direction that the suspension jets emerging from them overlap and as a result the soil is mixed and solidified over the entire circumference of the shield jacket 28 .

When manufacturing the tunnel lining, the procedure according to the invention is such that the shield 18 is first driven by the length of a formwork element 23a or 23b. The rearmost formwork element 23b is then moved forward into the area of the shield tail 24 and the earth space 27 surrounding the shield shell 28 in the region of the shield tail 24 is solidified with cement suspension which is pressed into the surrounding earth 27 by the injection nozzles 30 becomes. The shield 18 is then advanced further.

In the embodiment shown in FIGS. 3 and 4, the injection nozzles 30 are arranged in the walls 49 of injection pipes 50, which pivot about their longitudinal axes in depressions 51 on the outside of the shield jacket 28. are stored in cash. The outflow openings 33 for discharging the excess soil material are located between these injection pipes 50. Here, too, all injection pipes 50 can be connected to an inflow ring line, which is not shown in the drawing, however.

In the embodiment shown in FIGS. 5 and 6, the injection nozzles 30 are arranged in a rotatable ring 52 which can be rotated on the outside of the shield jacket 28 in a recess about the longitudinal axis of the shield 18. Since the rotatable ring 52 takes up a little more space, the pre-press cylinders 22 are set somewhat inwards and are supported on inwardly projecting brackets 54 of a formwork element 55 which is pulled forward together with the shield 18. The formwork element 23a brought forward is then installed immediately behind the element 55.

Since the ring 52 in the shield 18 can be rotated through 360 °, only a few injection nozzles 30 need be arranged on its circumference, which mix and solidify the part of the base lying in the region of the shield tail with cement suspension when the ring is rotated fully .

In the embodiment shown in FIGS. 7 and 8, a rotatable ring 52, which carries a mixing and milling disk or worm 56, is likewise arranged on the outer circumference of the shield jacket 28. The mixing or milling blades 57 of this milling disk 56 have a radial dimension d which corresponds to the desired outer circumference 58 of the lining 60. The injection nozzles 30 are arranged in the mixing blades 57 of the mixing screw 56, through which the cement suspension is pressed under high pressure into the soil 27 surrounding the shield jacket 28, the nozzles being directed towards the rear. Finally, a further embodiment is shown in FIGS. 9 and 10, which is designed somewhat differently than the previous ones. Here, in the area of the shield tail 24, a plurality of injection lances 63 are arranged distributed over the circumference of the shield jacket 28, which are staggered in two rows in the longitudinal direction of the shield. The injection lances 63 are rotatably and axially displaceably guided in the shield shell 28 and can be moved radially into the soil 27 surrounding the shield shell 28 and pulled back into the interior of the shield. They have 62 injection nozzles 30 at their outer ends, which are located on radially opposite sides and through which the suspension liquid is pressed out. The injection lances 63 can be rotated about their longitudinal axis.

The openings 33 for the discharge of excess soil and consolidation material surround the injection lances 63 in a ring-shaped manner, so that the excess material on the lances escapes along the interior of the cavity to be opened, where it or the like in suitable channels. can be collected, but which are not shown in the drawing.

While in the previously described embodiments the shield 18 can be driven continuously while at the same time cement suspension is injected into the soil surrounding the shield shell 28 under high pressure, in the embodiment according to FIGS. 9 and 10 the shield 18 must be stopped when the solidification of the the soil surrounding the shield shell is to take place. For this purpose, the injection lances 63 are first pushed one by one into the ground as far as the thickness of the lining shell to be produced. Then, while cement suspension is sprayed under high pressure from the openings 30 of the injection lance 63, this lance 63 slowly withdrawn in the radial direction into the interior of the shield 18, the emerging cement suspension cutting open the surrounding soil, circulating and mixing with the soil, while excess material exits inwardly through the ring opening 33 surrounding the lance.

As soon as all the lances have been withdrawn completely into the interior of the shield while injecting cement suspension, the shield can be advanced further and the last shuttering element 23b can be moved forward.

The invention is not limited to the exemplary embodiments shown and described, but several changes and additions are possible without leaving the scope of the invention. For example, the excess material accumulating during the consolidation of the ground surrounding the shield, like the pile detached from the face, can also be conveyed to the shaft by conveyor belts or wagons and from there to the surface. Furthermore, it is also possible, instead of a cement suspension, to press a cement mortar into the surrounding mountain range if it is coarse and has larger cavities.

Industrial applicability

The method and the device according to the invention can be used for excavating cavities such as tunnels, tunnels and caverns underground, especially in rolling mountains.

Claims

Expectations :

1. A method for lining and securing an underground cavity opened in the shield drive, in which a flowable, hardening mass is injected into the mountains surrounding the cavity, characterized in that the soil surrounding the shield extends over at least part of the shield length from Shield is mixed with the hardening mass in such a thickness that after hardening it forms the load-bearing lining of the opened cavity.

2. The method of claim 1, d a d u r c h g e k e n n ¬ z e i c h n e t that a cement suspension is used as the hardening mass, which is introduced under high pressure into the soil surrounding the shield.

3. The method according to claim 1 or 2, d a d u r c h g e ¬ k e n n e e c h n e t that the hardening mass prepared for days, conveyed to the shield and passed through this into the surrounding soil.

4. The method according to any one of claims 1 to 3, so that excess material is removed from the lining area produced in each case through openings in the shield or in a form following it, collected and removed after days.

5. Device for lining a subterranean cavity which has been driven in the shield drive, with a shield and a formwork adjoining this shield, surrounding the opened cavity or shielding expansion elements, in particular according to the method of one of the preceding claims, thereby indicates that devices (26) for injecting a hardening mass into the soil (27) surrounding the shield (18) and for mixing this soil with the hardening mass are attached to the shield (18).

6. The device according to claim 5, which also means that the injection device (26) is a high-pressure injection device for cement suspension.

7. The device according to claim 5 or 6, characterized in that the Injektionsvor¬ device (26) has injection nozzles (30) for the hardening mass, which is arranged at least over part of the length of the shield over the circumference in the shield jacket (28) and are directed at different angles against the soil (27) surrounding the shield casing (28).

8. Device according to one of claims 5 to 7, d a ¬ d u r c h g e k e n n z e i c h n e t that openings (33) for the discharge of excess soil and consolidation material are arranged in the shield (19), which are closed by pressure valve closures (34).

9. Device according to one of claims 5 to 8, since ¬ characterized in that the In¬ injection nozzles (30) in the walls (49) of Injektion¬ tubes (50) are arranged approximately parallel to the outside of the shield shell (28) to its generators are pivotally mounted about their longitudinal axes.

10. The device according to one of claims 5 to 9, that the injection tubes (50) are accommodated in depressions (51) of the shield jacket (28).

11. The device according to one of claims 5 to 10, since ¬ characterized in that the In¬ injection nozzles (30) in a on the outside of the shield shell (28) arranged and about the longitudinal axis of the shield (18) rotatable ring (52) are arranged .

12. The device according to one of claims 5 to 11, since ¬ characterized in that on the outer circumference of the shield (18) a rotatingly driven mixing and milling disc (56) is arranged, the mixing and milling blades (57) of a radial extent (d ) which correspond to the desired outer circumference (58) of the lining (60) and which carry the injection nozzles (30) for the hardening composition.

13. Device according to one of claims 5 to 12, since ¬ characterized in that the injection device has injection lances (63) which can be moved radially outwards and inwards in the shield casing (28) and on their in the surrounding soil (27) protruding ends (62) carry injection nozzles (30).

14. Device according to one of claims 5 to 13, since ¬ characterized in that the openings (33) for the discharge of excess soil and consolidation material surround the injection lances (63) in a ring shape. - -

15. The device according to one of claims 5 to 14, since ¬ characterized in that the Ab¬ discharge openings (33) to a discharge ring line (35) and the injection nozzles (30) to an inflow ring line (31) in the interior of the shield (18) are connected .