DE102018112613A1 - Method and device for removing cavities underground - Google Patents

Abstract

Method for removing cavities (1, 2) underground, in particular cavities (1, 2) with excavation cross-sections of at least 5 square meters, with production of at least one layer (16 - 19, 21 - 24) on an inner side (11) of an underground cavity (1, 2), wherein the deformable layer is produced by means of 3D printing.

Description

Field of the invention

The invention relates to a method and a device for the development of underground cavities, in particular cavities with excavation cross-sections of at least 5 square meters (hereinafter: m2).

State of the art

In underground mining, there are various methods to build structures in pressure or swellable mountains.

A building can be created according to the principle of resistance, if the occurring rock pressures are to be mastered with the today known, rigid expansion systems. A rigid expansion system withstands the rock pressure without significant deformations.

However, the level of expansion and thus also the application of the resistance principle are limited especially in the case of larger structural diameters in combination with large overlap. The space requirement increases strongly for a high expansion resistance, so that large breakout diameters are necessary. In pressure rock or swellable rock with high rock pressures and large diameters, structures according to the resistance principle are technically very difficult and can only be realized with great effort or not at all, and consequently are generally not economical either.

If the rock pressures and the deformations associated therewith are no longer manageable or economical with a rigid construction, different variants of a deformable expansion are used. When deformable expansion of a deformation of the mountain is permitted and subsequently reduced the resulting stress on the expansion.

For conventional, sequential jacking, there are various deformable expansion systems in combination with shotcrete. Upset elements, which are installed parallel to the tunnel axis on the tunnel wall and are filled with shotcrete, absorb the deformation. The load absorption and deformation in the compression elements is tangential to the tunnel profile.

• • Komprimierbarer Ringspaltmörtel, z.B. Compex: der Ringspalt zwischen Fels und dem Tübbing wird mit komprimierbarem Mörtel verpresst.
• • Flächenhafte Sandwich-Tübbingelemente, z.B. Solexperts hiDCon-F, Andra Bure: auf dem Tübbingsegment wird eine deformierbare Schicht aus gebrannten Tonröhrchen hinzugefügt.
• • Komprimierbarer Spritzbeton: ein deformierbarer Mörtel oder Beton wird pneumatisch an die Ausbruchsfläche gespritzt.

For machine, continuous propulsion, the above mentioned systems are not suitable because they are not compatible with segmental segments. Furthermore, the above-described systems with tangential deformation possibility no deformable layer between rock and inner shell with radial deformation possibility. Such systems with radial deformation possibility are also called planar systems. Various areal systems are known and used:

• • Compressible annular gap mortar, eg Compex: the annular gap between the rock and the tubbing is compressed with compressible mortar.
• • Large sandwich tubbing elements, eg solexpert hiDCon-F, Andra Bure: a deformable layer of fired clay tubes is added to the tubing segment.
• • Compressible shotcrete: a deformable mortar or concrete is pneumatically sprayed to the excavated surface.

Although these planar systems are suitable for the mechanical propulsion of tunnel tubes. However, these systems are only of limited suitability in the area of intersection structures or cross-passages. Junction structures require more complex geometries of expansion than consistent tunnel cross sections.

For pressing compressible mortar an annular gap is necessary. Therefore, it is only suitable for TBM jacking, where there is an annular gap between rock and tubbing. In branching or intersection structures, complex shell designs are required for the compression of compressible mortar.

Due to the complex geometry, the production of segmental segments with an additional, deformable layer for intersection and branch structures is extremely complex.

The state of the art is to finish the inner shell in one direction and to create the intersection or crosscut conventionally at a later time. The inner shell is then often created with special formwork carriages.

For the function of a deformable, planar system, the layer thickness and its deformation properties are important parameters. When using deformable shotcrete, both parameters are subject in practice with comparatively great uncertainties. The deformation properties and the thickness of the applied layer are very difficult to guarantee in a narrow tolerance range and are highly dependent on the machine operator and the method of application.

From the EP 0 557 269 A1 a system for Tunnelausbau in tubbing construction is known, which achieves a planned compliance with rock pressure through the use of springs.

A 3D printing method for concrete is in the EP 3 147 269 A1 explains which BCT cement is used.

Disclosure of the invention

The object of the invention is over the prior art improved devices and methods for the development of cavities underground, in particular of cavities with eruption cross-sections of at least 5 m2.

The object is achieved by a method according to claim 1 and a further method and a device according to the independent claims.

A first aspect of the invention relates to a method for the development of cavities underground, in particular of cavities with excavation cross-sections of at least 5 square meters, with producing at least one in the expansion state under the occurrence of rock pressure planned deformable or planned compliant layer on an inner side of an underground cavity wherein the deformable layer is produced by means of 3D printing. Typically, one or each of the at least one deformable layers may have multiple print layers, i. several print layers are printed for a deformable layer.

The smallest diameter of the cavity is typically 2 m, in embodiments at least 3 m or at least 4 m. The smallest diameter is the smallest opposing distance between two breakout surfaces of a cross section. Typical minimum sizes of cavities have a cross-section greater than 5 m ^2, or typically greater than 10 m ² , or typically less than 300 m ² . Typical embodiments include a planned deformable layer. As such, such planned deformable or compliant layers are known in the art to accommodate deformation of the surrounding rock and thus relieve stresses.

The deformability may typically be defined as a minimum plastic deformation, typically in the range of plastic deformation of at least 10% or at least 20% or at least 30% in the degraded state. Typically, the deformability of the at least one deformable layer is at least 40% or at most 80% or at most 90%. The deformability is typically the reduction of the volume, which is achievable with a plastic deformation before the resistance of the layer has increased to twice the compression limit, so the transition from elastic to plastic deformation.

The at least one deformable layer may also be defined by the fact that the at least one deformable layer has a modulus of elasticity that is relatively small for concrete. The at least one deformable layer typically has a strength of at most 20 MPa or at most 10 MPa or at most 5 MPa. The at least one deformable layer typically has a strength of at least 0.1 MPa or at least 0.2 MPa.

Additionally, in typical embodiments of methods of the invention, a rigid layer is formed radially within the at least one deformable layer. Typically, the rigid layer is also made by 3D printing. In this way one can work with a device for both types of layers, rigid and deformable. In further embodiments, prefabricated elements or in-situ concrete with formwork elements are used for the rigid layer.

Typically, the deformable layer is made with micropores. Typical micropores have a size of at most 16 mm or at most 8 mm or at most 4 mm. Typically, the micropores in the deformable layer are created by adding porous granules, foaming agents or foam to a print material used in 3D printing to make the deformable layer. The addition to the print material is typically carried out before the printing process and thus enables efficient work with the method according to the invention.

In typical processes, the deformable layer is made with macropores. In this case, a controller can be used to produce the macropores according to a specification. The macropores can also be shaped so that in particular deformations in the circumferential direction of the deformable layer are made possible to facilitate yielding of the layer.

Typically, the macropores are made in the deformable layer by providing recesses in selected printed layers during 3D printing. In this way, a simple and efficient creation of the macropores is possible.

Typically, the print material used for 3D printing includes cement or plastic. Depending on the requirements of the layer, the strength of the printed matter can be between 0.2 and 5 MPa or up to 20 MPa for the deformable layer or up to 55 MPa or up to 35 MPa for the non deformable layer can be selected. The print itself can be deformable or stiff, even deformable layers can be produced by means of micropores or macropores from a rigid print. The word "stiff" refers to a state after curing of the printed material. The basic material of the printed material can be cement or plastic. Properties such as deformability and strength of the printed material can be varied with aggregates. Possible additives are limescale, open- and closed-pore granules, eg glass foam, polystyrene, expanded clay, metal and plastic foams, gas pores either as a result of pore formers or by adding foam, sand and plastic, steel, carbon and glass fibers. Typically, the print material has a binder, typical binders are cementitious or plastic based.

Typically, in methods of the invention, before or during the application of another deformable layer, the inside of the cavity or the inside of a previously applied deformable layer is measured by means of a laser scanner. In this way, the layer to be applied can be adapted exactly to the existing conditions.

In typical processes, the thickness of the further deformable layer is adjusted in dependence on the measured inside of the previously applied deformable layer or the inside of the cavity. In typical processes, during the coating or printing of a layer, the already printed layer thickness of this layer under pressure is measured. In this way, the thickness of the layer can be created as accurately as possible. Typically, in methods of the invention, a pattern of pressure for creating voids, the width of a print jet, or the mixture of print material is adjusted as a function of the measurement.

In typical processes, the application of the at least one deformable layer or the at least one rigid layer is effected as a function of reference points. In this way, a specific inner profile of the deformable layer can be reliably achieved. Reference points may for example be arranged on an already finished cross-section or may be points which are continuously checked for displacements with respect to a fixed point, which may also be located outside the cavity or tunnel cross-section.

Typically, the at least one deformable layer has a thickness of at least 5 mm, at least 10 mm or at least 20 mm or at most 500 mm or at most 800 mm. In typical processes, the micropores or macropores are provided depending on a given deformability. In this way, by adjusting the micropores or the macropores a desired macroscopic deformation behavior can be adjusted.

One aspect of the invention relates to a method for the development of underground cavities, in particular cavities with eruption cross-sections of at least 5 m2, producing at least one deformable layer in the expansion state under the occurrence of rock pressure deformable layer, wherein the deformable layer produced by means of 3D printing and wherein the deformable layer is fabricated in a geometric shape depending on an inside of a downhole cavity or an inside of a previously applied deformable layer.

Typically, prior to making a layer, particularly a deformable layer or a plurality of deformable layers printed on top of each other, the inside of the cavity or the inside of the previously applied deformable layer is measured by means of a laser scanner and the result of this measurement in the manufacture of the following deformable Layer used. In this way, an optimal thickness adaptation to existing conditions is possible.

The eruption surface may be sealed or left unsealed prior to printing the first deformable layer of the at least one deformable layer. A seal, also called Erstversiegelung, can serve the occupational safety. By increasing the cohesion through the seal, in embodiments, the surface can be stabilized and the risk of retractions can be reduced. In typical embodiments, a network is injected with which can offer advantages as head protection.

In typical embodiments, rigid and compressible layers are combined, for example, interchangeably arranged. Typically, a plurality of deformable layers are first arranged or printed on the excavation surface, and then a rigid layer is applied on the inside.

For printing, a 3D printing unit is typically used which comprises a pumping system for pumping the printed matter and a robot, on the arm of which there is a print head with which the print material is applied.

For any breakout geometries, with typical methods of the invention, both deformable layers of given dimension and defined deformation properties as well as relatively rigid layers or combinations of deformable and rigid layers can be applied to the eruption surface, which may be sealed or unsealed. The first layer, typically a deformable layer, may be applied to both sealed breakout surfaces, eg, a shotcrete layer, or directly onto the unsealed rock. The layers may consist of one or more layers or printed layers. A layer typically refers to a print layer. Typical embodiments can be used in conventional, sequential or in machine, continuous propulsion, for example with tunnel boring machines.

Typical methods of the invention may be operated with mobile or stationary printing units. Among other things, in typical embodiments, the printing unit consists of a pump system and a robot or industrial robot, with typical robots used having at least 4, at least 5 or at least 6 axes. The robot comprises an arm having a plurality of degrees of freedom, for example at least 5 or 6, on the last element of which a print head is arranged with which the print material is applied to the breakout surface. The printing unit is typically mounted on a platform. In typical mobile printing units of embodiments, the platform is moved with caterpillars, wheeled or rail-mounted.

In typical processes, the mechanical properties such as strength and plastic deformability of a printed layer are not only dependent on the properties of the print material. The mechanical properties are also determined in typical processes by the choice of the patterns of the print layers of a layer.

The porosity of a printed layer with patterns typically consists, on the one hand, of the micropores in the print material itself and of the macropores of the pattern of the print layer. With the variation of this double porosity, layers can be produced in a very large range of deformability (for example from 0% to 85%) and strength (for example from 0.2 to 60 MPa).

With typical methods, both the width and the thickness of individual printed layers can be varied within a wide range. This allows the production of smooth or even surfaces for the inner shell, regardless of whether it is made with cast-in-place concrete or is made of segmental segments. This is particularly advantageous in branching or crossing structures with typically complex surface geometries, but can also offer great advantages for straight sections.

With typical methods, prefabricated deformable sheet or line elements having the deformable layer properties described herein can be made. Such prefabricated elements may be mounted directly on the excavation surface or used in combination with tubing segments or steel arches. The prefabrication can also take place outside the underground cavity, for example a tunnel.

list of figures

• 1 zeigt schematisch eine Vorrichtung, mit welcher typische Verfahren der Erfindung durchgeführt werden können;
• 2 zeigt schematisch ein Detail der Vorrichtung der 1 genauer beim Durchführen eines typischen Verfahrens;
• 3 zeigt schematisch ein Detail der Vorrichtung der 1 genauer beim Durchführen eines weiteren typischen Verfahrens;
• 4 bis 8 zeigen schematisch Muster, welche mit typischen Verfahren der Erfindung herstellbar sind;
• 9 zeigt in einem schematischen Ablaufdiagramm den vereinfacht dargestellten Ablauf eines typischen Verfahrens; und
• 10 zeigt schematisch verschiedene Kreuzungssituationen von Tunnelquerschnitten.

Hereinafter, embodiments of the invention will be explained with reference to the accompanying figures, in which:

• 1 schematically shows an apparatus with which typical methods of the invention can be carried out;
• 2 schematically shows a detail of the device of 1 more specifically, when performing a typical procedure;
• 3 schematically shows a detail of the device of 1 more specifically, when performing another typical method;
• 4 to 8th schematically show patterns that can be produced with typical methods of the invention;
• 9 shows in a schematic flow diagram the simplified flow of a typical process; and
• 10 shows schematically different crossing situations of tunnel cross sections.

Description of preferred embodiments

In the following, typical embodiments will be described, wherein for identical or similar parts partially the same reference numerals are used, partly for several different embodiments. In principle, the application is not limited to the various embodiments, but the scope is determined by the claims. In part, individual parts are explained only in connection with a figure, as far as these parts are shown in further figures, they are not necessarily described again.

1 schematically shows an apparatus with which typical methods of the invention can be performed. For printing typically a 3D printing unit 12 used, as shown schematically in the 1 is shown.

The printing unit 12 has a pumping system 9 for pumping the printed matter and a robot 5 on whose arm is a print head 7 is located, with which the printed material is applied. The print material is conveyed via a line, not shown, from a mixer or reservoir to the pumping system.

Furthermore, the printing unit 12 a scanner 8th on, which is designed as a real-time scanner system with a laser scanner. Furthermore, the printing unit comprises a on a chassis 4 built-up ground platform 6 which the robot 5 and a control computer 10 with a GUI and a wireless interface for transferring data.

With the printhead 7 the print material is on an eruption surface 11 a main tunnel 1 , which represents an inside of an underground cavity, applied. The print material can in embodiments on the excavation surface 11 directly on a surface of a rock 3 be applied.

In the 1 is also a crosscut 2 the main tunnel 1 shown, wherein producing an inner formwork with the printing unit 12 in the crossing area of the main tunnel 1 with the crosscut 2 offers special advantages, since a flexible adaptation to different geometries is possible.

The 2 shows how with the printing unit 12 of the embodiment of 1 printed layers 16 . 17 and 18 variable thickness can be generated. The breakout surface 11 has an irregular contour.

For example, in order to be able to produce a uniform inner shell for a uniform tunnel cross-section, irregularities of the outbreak surface can be compensated for automatically using methods according to the invention or typical 3D printing units. Typical embodiments of the invention, for example typical 3D printing units, include a print head with a thickness driver. The thickness control includes, for example, a flap or aperture on the print head of the 3D printing unit. The thickness control is adapted to affect a thickness of the printed layer. Typical embodiments of 3D printing units include delivery rate control or speed control. The delivery amount control, the thickness control, or the speed control are used individually or jointly in typical methods of the invention to adjust the amount of printed material applied or the thickness of a print layer.

The print layers 16 . 17 and 18 of the 2 are layers of a deformable layer having a strength in this example of 1.5 MPa and a deformability of 50%. Due to the thickness adaptation of the print layers 16 . 17 and 18 The resulting layer almost completely compensates for the irregularities of the eruption surface. By applying a further layer with variable thicknesses of the individual printed layers of the further layer, a further homogenization can be achieved.

In the 3 another embodiment of a multi-layer tunneling installation is shown, which can be produced with typical methods and devices of the invention. On an outbreak area 11 were in this example in contrast to the example of 2 first several non-deformable, provided for compensation, layers 16 - 19 applied. The layers 16 - 19 have a strength of 30 MPa and at least substantially no deformability and serve to irregularities of the excavated surface 11 compensate.

The layers 16 - 19 of the embodiment of 3 are each at least substantially similar in thickness, however, as in the 3 shown schematically not all layers applied at each point to achieve height compensation. In this way, but not necessarily, to work with a printhead, which has no mechanical thickness control on the print head.

On the last layer 19 already four highly deformable layers 21 - 24 applied, which have a strength of only 1.5 MPa and a deformability of 70%. The high deformability is due to macropores and micropores in the highly deformable layers 21 - 24 reached.

Typical embodiments include combinations of deformable layers having different material properties. For example, external compensation layers may have a lower or higher deformability than further inner layers.

The final layer is a rigid layer 25 on the innermost highly deformable layer 24 applied. The rigid layer 25 has a tenacity of 30 MPa and a deformability of less than 5%, or is substantially non-deformable.

In the 4 It shows how the print pattern of part of an applied print layer can look like in typical processes. The print layer of 4 comes with a comparatively simple one parallel print pattern of several print lines 32 created. The printed snakes 32 are printed in parallel in one go with a typical printing unit, with a turn at the end of a straight line 33 is made. There are hardly or no macropores in the layer, which several layers of pressure according to the 4 In particular, macropores can be avoided by displacing the individual, superimposed webs by half a web width. The pattern of 4 is particularly suitable for rigid but also for deformable layers with only little deformability.

In the 5 is another printing pattern which can be produced by typical methods. The print pattern of 5 includes individual printed snakes 32 which meander slightly, leaving little gaps 36 arise in the finished layer with multiple print layers corresponding to the printing pattern of 5 to form macropores.

In the 6 is a print pattern with more meandering print snakes 32 shown, leaving large gaps 37 arise. In addition, superimposed print layers are printed with unaltered and identical pattern (simple stacking), so is the print queue 38 the subsequent print layer just above the print queue 32 the first print layer. Both print layers are like all 4 to 8th only schematically shown in fragmentary form.

In the 7 a printing pattern is shown which has similar or identical printing lines 32 and 38 like the print pattern of the 6 used, however, the print layers 32 and 38 staggered (staggered stacking). It comes to very large gaps, which ensure a great deformability.

In the 8th a printing pattern is shown which has similar or identical printing lines 32 and 38 like the print patterns of 6 and 7 used, however, the print layers 32 and 38 rotated by 90 ° (staggered and crossed stacking). There are large gaps, which ensure a large deformability, but a comparatively high strength can be achieved.

A typical method of the invention is in 9 shown schematically. The method can be used to create a plurality of layers, in particular a plurality of deformable layers and possibly at least one rigid layer. The method may use other typical features described herein.

In addition to the 3D printing produced print patterns of 4 - 8th Many other print patterns can be used. In particular, the print pattern can be produced with print material having micropores. For example, the print pattern is the 8th can be combined well with micropores to further increase deformability with acceptable strength.

First, in a block 110 a positioning of the printing unit by means of conventional measurement or by position recognition on the basis of previously installed reference points. In a block 120 For example, a real-time scanner system captures the geometry of the eruption surface or deformable or rigid layers previously applied by printing. The real-time scanner system can be realized with a central laser scanner or with a system of different scanning modules.

In a block 130 a detection of the actual state and a planning of the subsequent development, typically the subsequent deformable or rigid layer, are applied, whereby a three-dimensional virtual model of the outbreak geometry is created with the scanner data. In this model, the desired tunneling, ie the next deformable layer and rigid layer to be created is integrated. It also defines the order, dimension and properties of the individual print layers for the next layer to be created.

After a verification of the planned expansion by a user in block 140 the print program will follow the instructions in the block 130 created and the printing material is prepared. In a block 150 The different layers are applied to the eruption surface. The printhead applies either a cement or plastic-based mortar in layers to the surface in layers. Quick-setting mortar can also be applied overhead.

The three-dimensional model is in a block 160 updated with acquired scanner data and with the target model of the expansion in block 170 compared.

Will be in a block 170 Having determined that the particular layer is already finished, the process jumps to block 180 in which it is checked whether there is still a layer to print. If so, the procedure jumps to block 130 in which the next layer, a deformable or a rigid layer, is then planned.

Will be in the block 170 however, found that the currently produced layer is not ready yet is set, the method jumps to the block 150 back, so that the updated model is used for further printing. In typical embodiments, a straight into block 150 printed print layer immediately in step 160 recorded and modeled and thus affects the printing of the next printing layer of the currently in-pressure deformable or rigid layer.

If in block 180 If it is determined that all layers are printed, the process is in block 190 completed.

In the 10 are for explanation intersection situations each one main tunnel 1 each with a crosscut 2 shown in a schematic sectional view from above. The left figure shows a branch structure, with which the cross beat 2 from the main beat 1 branches. In the right picture of the 10 is a niche with an approach 50 shown for future extensions. Particularly in the case of non-circular tunnel cross sections, complex geometries occur in such intersections, which have to be taken into account during tunnel construction. With the methods and devices according to the invention, customized segments for such geometries can be created flexibly.

The invention is not limited to the embodiments described above. The scope of the invention is defined by the claims.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0557269 A1 [0013]
• EP 3147269 A1

Claims (16)

Method for the expansion of cavities (1, 2) underground, in particular of cavities (1, 2) with excavation cross-sections of at least 5 square meters, with Producing at least one layer (16 - 19, 21 - 24) which is intended to be deformed under the appearance of rock pressure in the expansion state on an inner side (11) of an underground cavity (1, 2), - The deformable layer is produced by means of 3D printing. Method according to Claim 1 In addition, wherein a rigid layer (25) is produced radially within the at least one deformable (16-19, 21-24) layer. A method according to any one of the preceding claims, wherein the deformable layer (16-19; 21-24) is made with micropores. Method according to Claim 3 wherein the micropores in the deformable layer (16-19; 21-24) are formed by adding porous granules, foaming agents and / or foam to a print material which is used in the 3D printing to produce the deformable layer (16-19; 24) is used. A method according to any one of the preceding claims, wherein the deformable layer (16-19; 21-24) is made with macropores. Method according to Claim 5 wherein the macropores are formed in the deformable layer by providing recesses (36) in selected printed layers during 3D printing. Method according to one of the preceding claims, wherein the printing material used for the 3D printing comprises cement and / or plastic. Method according to one of the preceding claims, wherein before and / or during the application of a further deformable layer (17-19, 21-24) the inside of a previously applied deformable layer (16-19, 21-23) is detected by means of a laser scanner (8 ) is measured. Method according to Claim 8 in that the thickness of the further deformable layer (17-19, 21-24) is adjusted as a function of the measured inside of the previously applied deformable layer (16-19, 21-23). Method according to one of the preceding claims, wherein the at least one deformable layer (16-19, 21-24) has a thickness of at least 5 mm and / or at most 800 mm. Method according to one of the preceding claims, wherein the at least one deformable layer has a strength of at least 0.1 MPa and / or at most 60 MPa. Method according to one of the preceding claims, wherein the at least one deformable layer (16-19, 21-24) has a deformability of at least 20% and / or at most 80%. Method according to one of the preceding claims, wherein the at least one deformable layer (16-19, 21-24) and / or the at least one rigid layer (25) is produced as a function of reference points. Method for the expansion of cavities (1, 2) underground, in particular of cavities (1, 2) with excavation cross-sections of at least 5 square meters, with Producing at least one layer (16-19, 21-24) which is intended to be deformed under the occurrence of rock pressure in the expansion state, - wherein the deformable layer (16 - 19, 21 - 24) is produced by means of 3D printing, and - wherein the deformable layer (16-19, 21-24) in a geometric shape in dependence on an inner side (11) of an underground cavity (1, 2) or an inner side of a previously applied deformable layer (16-19, 21-23 ) will be produced. Method according to Claim 14 in which, prior to the production of the deformable (16-19, 21-24) layer, the inside (11) of the cavity (1, 2) or the inside of the previously applied deformable layer (16-19, 21-23) are laser scanned is measured and the result of this measurement is used in the production of the deformable layer (17-19, 21-24). Device, in particular 3D printing unit (12), adapted to at least one of the methods of Claims 1 to 15 perform.

Images