Method for building a traffic tunnel, a pipe tunnel, or a pressurised water tunnel by way of the tubbing construction method

Abstract

The present invention relates to a method for building a traffic tunnel, a pipe tunnel or a pressurised water tunnel by way of the tubbing construction method, in which tubbing components (10) are assembled in a mechanically formed borehole in rock in order to form a closed lining in the form of a tubbing tube, and the annular gap between the borehole and the outer wall of the tubbing tube is filled with a composition which comprises reaction resin, which cures by polymerisation, and filler material, the reaction resin that cures by polymerisation being fed to the filler before or during the conveyance into the annular gap and being mixed with the filler and distributed therein, characterised in that the composition is cement-free and the filler material comprises an inorganic material which is not reactive with water and which has an average particle size ≤ 500 micrometres.

Description

[0001] Method for the construction of a traffic tunnel, a pipeline tunnel or a pressure water tunnel using the segmental construction method

[0002] The present invention relates to a method for constructing a traffic tunnel, a pipeline tunnel (lines for electricity, water or gas) or a pressure water tunnel (headrace tunnel for hydroelectric power plants) using a segmental construction method, in which segmental components are assembled in a machine-made bore in the rock or soil to form a closed lining in the form of a segmental tube, and the annular gap between the bore and the outer wall of the segmental tube is filled with a reaction resin and filler that hardens by polymerization.

[0003] Such a tunnel construction method using segmental lining is known from EP 3 913 186 A1. In this known method, the annular gap between the outer wall of the segmental lining and the surrounding rock is filled with a mixture of cement as a filler and a reaction resin that hardens by polymerization.

[0004] Most construction guidelines for tunnels are also based on the use of a one-component cement suspension / mortar or a two-component cement-water glass combination as filling material in order to ensure that it has sufficient load-bearing capacity.

[0005] However, large quantities of carbon dioxide (CO2) are released during cement production. The reaction of the cement with water also releases hydroxide ions, which can accumulate in the surrounding soil and groundwater. This can lead to an increase in the pH of the groundwater at these locations and to a mobilization of the heavy metals contained therein, such as cadmium or arsenic. The object of the present invention is to provide an improved method for constructing a traffic tunnel, a pipeline tunnel, or a pressurized water tunnel using the segmental construction method.

[0006] To achieve this object, the method having the features of patent claim 1 serves. Advantageous embodiments of the invention are specified in the subclaims.

[0007] According to the invention, a water-inactive inorganic material is used as the filler, to which the polymerization-curing reaction resin is added before or during injection into the annular gap. The reaction resin is mixed with the filler and distributed therein before or during injection into the annular gap.

[0008] It has now surprisingly been found that a water-reactive inorganic material with an average particle size of < 500 pm can be used as a filler in the process described in EP 3 913 186 A1 and still achieve sufficient load-bearing capacity of the annular gap filling. By using the water-reactive material with a small particle size as a filler, good flowability of the composition can still be achieved, so that the materials can be pumped over long distances from the tunnel entrance to the place of use and used there to fill the annular gap.

[0009] It was also surprisingly discovered that the use of the non-water-reactive inorganic material results in improved workability while simultaneously maintaining sufficient strength and resilience of the composition. The use of non-water-reactive material also results in a neutral filler pH, thus avoiding soil contamination due to a lowering of the pH value.

[0010] Furthermore, the process according to the invention has the advantage that no further chemical additives such as flow improvers or setting agents, which can pollute the soil, have to be used.

[0011] The composition also has a high ductility with sufficient strength , which has the advantage that tensions in the soil can be compensated by the annular gap filling and this does not break .

[0012] The composition used to fill the annular gap in the process according to the invention is cement-free, meaning it contains no cement. Instead, the composition comprises a polymerization-curing reaction resin and a filler, wherein the filler comprises a non-water-reactive inorganic material having an average particle size of < 500 pm.

[0013] For the purposes of this invention, a water-reactive inorganic material is an inorganic material that reacts with water only to a negligible extent at room temperature. It is thus inert toward water. Preferably, the material is barely soluble or only slightly soluble in water and forms a suspension with it.

[0014] In an advantageous embodiment, the water-reactive inorganic material has an average particle size of 0.5 to 500 μm, such as 0.5 to 300 μm. In an advantageous embodiment, the water-reactive inorganic material has an average particle size of <200 μm, in particular <100 μm. The water-reactive inorganic material can preferably have an average particle size of 5 to 100 μm. The particle size can be measured by means of grain size distribution.

[0015] In a preferred embodiment, the filler consists of the non-water-reactive inorganic material.

[0016] Porous fillers can be used as inorganic materials that are not reactive with water.

[0017] Inorganic materials that are not reactive with water can be used, for example, calcite (calcite), silt, clay, quartz flour, fly ash, dust or flour or mixtures thereof.

[0018] In a preferred embodiment, the non-water-reactive inorganic material comprises or consists of calcium carbonate.

[0019] In a preferred embodiment, the non-water-reactive inorganic material comes from recycling processes, such as residues from crushing or processing plants.

[0020] In a preferred embodiment, the filler is used in the form of an aqueous suspension, which is mixed with and distributed throughout the polymer-curing reactive resin. This allows for a homogeneous annular gap filling.

[0021] In an advantageous embodiment, the polymerization-curing reactive resin is a reactive resin that cures by polyaddition, polycondensation, or radical polymerization. Particular preference is given to using a reactive resin based on acrylate or silicate resin, polyurethane, epoxy resin, or polyester resin. By formulating the components of the reactive resin, the curing behavior of the reactive resin can be adjusted as desired, both to ensure rapid curing in the annular gap and to prevent premature curing during transport to the annular gap.

[0022] The composition may comprise 20 to 90 vol% filler, preferably 40 to 70 vol% and especially 55 to 65 vol% filler.

[0023] Furthermore, the composition may comprise 5 to 50 vol.% reaction resin, preferably 20 to 40 vol.% and in particular 35 to 35 vol.% reaction resin.

[0024] Furthermore, the composition may comprise 0.5 to 30 vol.% water, preferably 1 to 20 vol.% and in particular 5 to 15 vol.% water.

[0025] In an advantageous embodiment, the composition consists of reaction resin, non-water-reactive inorganic material and water.

[0026] In a preferred embodiment, the filler is mixed with the reaction resin which cures by polymerization and is distributed therein. After combining the reaction resin and filler, these two components are conveyed through a mixing device. The mixing device is preferably a static mixer or a compulsory mixer. A static mixer has a line in the form of a tube through which the components to be mixed are conveyed. Located in the tube are flow-guiding elements which divide the material flow and then recombine it, thereby achieving mixing. A compulsory mixer comprises a stationary container in which a mixing tool, e.g. with a propeller, screw or blades, rotates. Commonly used compulsory mixers are colloidal mixers and dissolvers.

[0027] The invention is described below using an embodiment in the drawings, in which:

[0028] Fig. 1 shows a schematic detailed view in section in the area of ​​a shield tail of a tunnel boring machine, behind which segmental components are continuously inserted to form a segmental tube,

[0029] Fig. 2 shows a schematic side view of a tunnel boring machine with a front cutting wheel and an adjoining shield casing and below it a section showing a detail in the vertical upper end area of ​​the tunnel boring machine and the bore with inserted segmental components,

[0030] Fig. 3 shows a perspective view in cross-section transverse to the longitudinal axis of the tunnel bore with installed segmental elements and a filling of an annular gap between outer walls of the segmental elements and the bore in the rock,

[0031] Fig. 4 shows a schematic representation of the production of the injection mass for filling the annular gap, wherein the filler is first mixed with water to form a suspension, which is then mixed with reaction resin in a mixer to form the injection mass intended for filling the annular gap.

[0032] The field of application of the method according to the invention will now be explained with reference to Fig. 1 to 3. The borehole is created in the underground by a tunnel boring machine, in the exemplary embodiment shown a shield machine 1, which is shown in a simplified side view in Fig. 2 at the top. The shield machine 1 is provided at the front with a cutting wheel 2, behind which is a shield casing 4 which is formed by a steel cylinder sleeve with a slightly smaller diameter than the cutting wheel 2. The equipment and machines required for operation are housed in the shield casing 4, in particular drives, a tunneling mechanism and equipment for installing the segmental components 10 made of concrete to form the tunnel lining are housed in the interior of the shield casing 4.The installation of the segmental components 10 takes place a few meters behind the cutting wheel 2, i.e., very shortly after the production of the relevant bore section, whereby a robot-like device, the so-called erector (not shown), is used to install the segmental components 10 in the rear part of the shield casing 4, the so-called shield tail 6. The tunnel boring machine advances by means of mechanical feed means which start at the front end, i.e., the foremost ring of segmental components of the tunnel lining, and which push the tunnel boring machine forward supported by this.

[0033] Fig. 1 shows a schematic sectional view of the upper region of a borehole that has just been drilled, with only an upper end region of the shield tail 6 shown by the tunnel boring machine and only an upper end region of the most recently installed rings of segmental components 10 shown by the tunnel lining. As shown in Fig. 1, successive rings of segmental components 10 are sealed by seals 12.

[0034] From the detail in the lower part of Fig. 2 it can be seen that the outer diameter of the cutting wheel 2 is slightly larger than the outer diameter of the adjoining shield casing 4, which is why the bore in the surrounding rock has a slightly larger diameter than the shield casing 4. Furthermore, it can be seen from the detailed view in the lower part of Fig. 2 that, since the segmental components 10 are each assembled to form a ring at the rear inside the shield tail, which ring then moves backwards out of the shield tail 4 as the tunnel boring machine advances, the outer diameter of the ring segment composed of the segmental components is therefore still smaller than the diameter of the bore in the rock created by the cutting wheel 2. Therefore, a free space remains between the outer casing of the tunnel lining formed by the segmental components 10 and the inner wall of the bore in the rock created by the cutting wheel 2.This gap is called the annular gap. As explained above, the annular gap must be filled with an injection compound to embed and support the tunnel lining in the bore.

[0035] To produce the injection compound for filling the annular gap, reaction resin and filler are brought together in a container of a compulsory mixer 20 located inside the shield tail and mixed by a compulsory mixer rotating in the container 20. The mixed injection compound is then driven by a pump 22 from the compulsory mixer 20 and conveyed through a line. The injection compound is fed into a line 24 which initially leads radially outwards into the outer wall of the shield tail, where it bends at 90° in a cavity in the shield tail 6 and in a further section runs parallel to the longitudinal axis of the cylindrical shield tail 6 to its end, where the line 24 opens towards the annular gap. There may be several of these lines 24, which are also present in conventional tunnel boring machines and are referred to as pilasters.

[0036] At the rear end of the shield tail 6, brush seals 8 are located on both the inner and outer walls, sealing the end region of the shield tail 6, on the one hand, from the outer wall of the last-formed ring of segmental segments 10, and, on the other hand, sealing the outer wall of the shield tail 6 from the surrounding rock. These brush seals 8 are intended to ensure that no injection material pressed from the end of the pilaster 24 into the annular gap is pushed forward beyond the filling of the annular gap or beyond the end region of the shield tail 6.

[0037] In this way, the injection medium is pumped from the container of the compulsory mixer 20 through the line leading from the container 20 by means of the pump 22 and further through the pilaster 24 into the annular gap, so that as the drilling progresses through the tunnel boring machine, an annular gap filling 100 is continuously formed in the resulting annular gap between the tunnel lining and the surrounding rock 102. As a rule, several pilasters 24 are present, e.g. six pilasters distributed around the circumference of the shield tail 6, which pump injection material into the annular gap distributed around the circumference in order to fill it and, after the annular gap filling 100 has hardened, to form a stable bedding for the tunnel lining composed of the segmental components 10.

[0038] In Fig. 3 it can be seen that the segmental components 10 are each provided with an injection opening 11 penetrating the segmental component. These injection openings 11 are normally closed by seals. The injection openings 11 serve to fill any remaining or newly formed cavities in the annular gap after the annular gap filling 100 has hardened by a further injection of mixed reaction resin and filler. Fig. 4 shows a very schematic illustration of an embodiment of the method according to the invention. In this case the filler is formed by a mixture of water and inorganic material that is not reactive with water. Here, the inorganic material 50 which is not reactive with water (schematically indicated by a bag) is filled into the container 22 and mixed therein with water supplied from a water container 24, after which the mixture is pumped via a pipe into an aeration tank 80.In the aeration tank 80, the mixture is circulated by a rotating propeller. In parallel, two pumps 60 convey two monomer components A, B, which are brought together behind the outlet of the pumps 60 and pressed through a static mixer 62. From the outlet of the static mixer 62, the reaction resin is conveyed into an inlet of a static mixer 64. The static mixer 64 also has a second inlet for the line from the loading tank 80, through which the filler suspension is fed. In the mixer 64, the reaction resin and the filler suspension are mixed together, whereby for this purpose the mixer 64 can also be designed as a static mixer. After mixing the filler suspension and the reaction resin, the resulting mixture is further conveyed for injection into the annular gap, in particular into the pilasters 24, the outlet openings of which open into the annular gap at the end of the shield tail 6.

Claims

Claims: Method for constructing a road tunnel, a pipeline tunnel or a pressurized water tunnel using segmental lining, in which segmental lining components (10) are assembled in a machine-produced borehole in rock or soil to form a closed lining in the form of a segmental tube, and the annular gap between the borehole and the outer wall of the segmental tube is filled with a composition comprising polymerization-curing resin and filler, wherein the polymerization-curing resin is supplied to the filler before or during conveyance into the annular gap, is mixed with the filler and distributed therein, characterized in that the composition is cement-free and the filler comprises a non-water-reactive inorganic material having an average particle size < 500 pm.A method according to claim 1, characterized in that the non-water-reactive inorganic material has an average particle size of 0.5 to 300 pm, preferably 5 to 100 pm. A method according to claim 1 or 2, characterized in that the filler consists of the non-water-reactive inorganic material. A method according to any one of the preceding claims, characterized in that the non-water-reactive inorganic material comprises or consists of calcium carbonate. A method according to any one of the preceding claims, characterized in that the non-water-reactive inorganic material is selected from calcite, silts, clays, quartz flour, fly ash, dusts or flours, or mixtures thereof. A method according to any one of the preceding claims, characterized in that the non-water-reactive inorganic material originates from a recycling process. A method according to any one of the preceding claims, characterized in that the filler is used as an aqueous suspension. A method according to any one of the preceding claims, characterized in that the polymerization-curing reaction resin is a polymerization resin that cures by polyaddition, polycondensation, or radical polymerization.A method according to any one of the preceding claims, characterized in that a reactive resin based on acrylate or silicate resin, or on polyurethane, or on epoxy resin, or on polyester resin is used. A method according to any one of the preceding claims, characterized in that the composition comprises 5 to 50 vol% reactive resin, preferably 20 to 40 vol% reactive resin. A method according to any one of the preceding claims, characterized in that the composition comprises 20 to 90 vol% filler, preferably 40 to 70 vol% filler. A method according to any one of the preceding claims, characterized in that the composition consists of a reaction resin, a non-water-reactive inorganic material, and water. A method according to any one of the preceding claims, characterized in that the filler is added to the polymerizing reaction resin prior to polymerization. A method according to any one of the preceding claims, characterized in that the filler is mixed with and distributed in the polymerizing reaction resin by mixing both components, preferably a static mixer (64) or a forced mixer (20), after the reaction resin and filler have been combined.Use of a composition comprising a polymerization-curing reaction resin and filler for filling the annular gap between the bore and the outer wall of a tunnel lining, wherein the filler is cement-free and comprises a non-water-reactive inorganic material having a particle size < 500 pm.

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