Concrete tunnel lining utilizing TBM hole digging waste in situ and preparation method

Abstract

The invention belongs to the technical field of tunnel linings, and particularly relates to a concrete tunnel lining utilizing TBM hole digging waste in situ and a preparation method. The concrete tunnel lining sequentially comprises a primary lining layer, a waterproof layer and a secondary lining layer from inside to outside, the primary lining layer is connected with surrounding rock and is made of sprayed concrete prepared from TBM hole digging sand-gravel materials, the waterproof layer is made of high-impermeability ECC materials prepared from TBM hole digging materials, and the secondary lining layer is made of high-impermeability ECC materials prepared from TBM hole digging materials. And the secondary lining layer is formed by compounding a high-protective-property ECC material prepared by TBM hole digging and a reinforcing mesh. According to the method, the in-situ recycled TBM hole digging waste serves as the aggregate to be used for the high-protection type composite tunnel lining, the TBM hole digging waste is converted into the tunnel lining material, generation and accumulation of a large amount of waste are avoided, effective recycling of resources is achieved, the mining requirement for natural resources is reduced, and resource consumption is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel lining, and in particular relates to a concrete tunnel lining utilizing TBM excavation waste in situ and a preparation method thereof. Background Art

[0002] The TBM hard rock tunnel boring machine construction method has been widely used in large-scale water diversion projects and pumped storage power stations because of its fast construction speed, high safety, flat excavation surface and low cost. TBM tunnel excavation sand and gravel slag has the characteristics of large needle-like content, excessive stone powder content and high water content, which cannot be used as concrete aggregate. Therefore, it is landfilled or piled up as engineering waste, which not only increases the cost of engineering construction, but also causes soil erosion and soil pollution, which is not in line with the concept of green engineering. Recycling TBM tunnel excavation materials and processing them into aggregates for concrete preparation is an effective treatment method. The current preparation technology scheme is to mix TBM coarse aggregate with ordinary concrete coarse aggregate, but the recycled TBM fine aggregate has not been effectively utilized.

[0003] On the other hand, water diversion tunnels and water diversion tunnels in water diversion projects and pumped storage power stations are exposed to the complex environment of water pressure and ambient temperature changes for a long time. The concrete will inevitably crack. The cracks cannot be effectively controlled. The protective layer of the concrete lining gradually falls off under the scouring of water flow, causing leakage problems in the structure and greatly shortening the service life of the structure. Therefore, how to improve the brittle cracking of concrete, improve the impermeability of the lining and the durability of the tunnel structure is an urgent problem to be solved. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a concrete tunnel lining and a preparation method that utilizes TBM tunnel excavation waste in situ. The method recycles and processes TBM tunnel excavation waste in situ as aggregate for high-protection composite tunnel lining, converts TBM tunnel excavation waste into tunnel lining material, avoids the generation and accumulation of large amounts of waste, realizes the effective recycling of resources, reduces the demand for natural resource exploitation, and reduces resource consumption.

[0005] The technical solution of the present invention is: a concrete tunnel lining that utilizes TBM excavation waste in situ, the tunnel lining is a multi-layer composite structure, which includes a primary lining layer, a waterproof layer and a secondary lining layer from the inside to the outside, the primary lining layer is connected to the surrounding rock and is made of shotcrete prepared from TBM excavation sand and gravel, the waterproof layer is made of high-impermeability ECC material prepared from TBM excavation materials, and the secondary lining layer is made of a composite of high-protective ECC material prepared from TBM excavation materials and a steel mesh.

[0006] The thickness ratio of the primary lining layer, the waterproof layer and the secondary lining layer is 1:0.2~0.5:2~4.

[0007] The primary lining layer comprises, by weight, 300-360 parts of P·O42.5 ordinary Portland cement, 180-220 parts of water, 40-80 parts of Class F II fly ash, 900-960 parts of TBM machine-made sand, 780-820 parts of crushed stone, 3.20-4.45 parts of naphthalene-based high-performance water reducer and 3.2-4.4 parts of silicate accelerator.

[0008] The machine-made sand is TBM excavation material with a particle size of less than 5 mm, and the crushed stone is TBM excavation material with a particle size of 5-10 mm.

[0009] The waterproof layer comprises, by weight, 766-830 parts of P·O42.5 ordinary Portland cement, 446-510 parts of Class F II fly ash, 383-510 parts of fine TBM sand, 383-510 parts of water, 10-17 parts of POM fibers and 0.8-1.5 parts of polycarboxylic acid powdered water reducing agent.

[0010] The particle size of the fine TBM sand material is less than 0.15 mm.

[0011] The second lining layer includes, by weight, 700-830 parts of cement, 446-575 parts of fly ash, 446-574 parts of fine TBM sand, 446-510 parts of water, 25-35 parts of PE fiber, 1-2.1 parts of polycarboxyl powdered thickener and 2.4-3.5 parts of polycarboxylic acid powdered water reducer.

[0012] The particle size of the fine TBM sand material is less than 0.15 mm.

[0013] A method for preparing a concrete tunnel lining in situ using TBM excavation waste comprises the following steps: S1: Construction of primary lining, the specific process is: S11: Drying the excavated material from the TBM hole; S12: The dried TBM excavated material is screened according to the particle size into four parts: >10mm, 5-10mm, 0.15-5mm and <0.15mm; S13: crushing the TBM excavated material with a diameter of more than 10 mm in step S12, and screening the material into two parts with a particle size of 5-10 mm and less than 5 mm; S14: The 5-10 mm TBM hole excavation materials in step S12 and the 5-10 mm TBM hole excavation materials in step S13 are mixed in a weight ratio of 1:1-2 to obtain crushed stones for configuring the primary lining 1; S15: The TBM excavation materials of 0.15-5 mm and less than 5 mm in S12 are mixed in a weight ratio of 1:2-4 to obtain TBM machine-made sand for configuring the primary lining; S16: The crushed stone obtained in step S14 and the machine-made sand obtained in step S15 are mixed, by weight, with 288-450 parts of cement, 180 parts of water, 0-90 parts of fly ash, 845-1076 parts of machine-made sand, 689-913 parts of crushed stone and 3.6-5.2 parts of water reducing agent, and stirred for 2-4 minutes to prepare TBM hole excavation fine stone concrete for the primary lining layer 1; S17: The fine stone concrete obtained in step S16 is sprayed to obtain a primary lining; S2: Construction of waterproof layer, the specific process is: S21: The fine TBM sand with a diameter of less than 0.15 mm obtained in step S12 is mixed with 766-830 parts of cement, 383-510 parts of fine TBM sand and 446-510 parts of fly ash by weight for 1 minute, and after the three are evenly mixed, 383-510 parts of water and 0.8-1.5 parts of water reducer are added and stirred for 1 minute. After obtaining a uniform flowing slurry, 10-17 parts of POM fiber are added and stirred for 3 minutes to obtain a high impermeability ECC material; S22: After the primary lining layer obtained in step S1 meets the construction conditions, pouring is performed by pumping to obtain a waterproof layer; S3: Construction of the second lining layer, the specific process is: S31: After the waterproof layer obtained in step S2 meets the construction conditions, tie the steel mesh; S32: The fine TBM sand with a diameter of less than 0.15 mm obtained in step S12 is mixed with 700-830 parts of cement, 446-574 parts of fine TBM sand and 446-575 parts of fly ash by weight for 1 minute, and after the three are evenly mixed, 446-510 parts of water and 2.4-3.5 parts of water reducer are added and stirred for 30 seconds, and 1-2.1 parts of thickener are added and stirred for 1 minute, and after obtaining a uniform flowing slurry, 25-35 parts of PE fiber are added and stirred for 3 minutes, and finally a highly protective ECC material is obtained; S33: The highly protective ECC material obtained in step S32 is poured by pumping to finally obtain a second lining layer, thereby completing the preparation of the tunnel lining.

[0014] The technical effects of the present invention are as follows: 1. The present invention uses in-situ recycled TBM excavation waste as aggregate for high-protection composite tunnel lining, converts TBM excavation waste into tunnel lining material, avoids the generation and accumulation of a large amount of waste, realizes the effective recycling of resources, reduces the demand for exploitation of natural resources, and reduces resource consumption; 2. The present invention can significantly improve the strength of tunnel lining through reasonable material ratio and the use of multi-layer composite structure, including primary lining, waterproof layer, and secondary lining design, so that it has better compression resistance, shear resistance and seepage resistance, improves the durability of tunnel lining, and extends the service life of the tunnel. At the same time, the lining structure is optimized through the multi-layer composite structure, the overall stability of the tunnel is improved, and the risk of geological disasters is reduced; 3. The present invention uses TBM excavation waste as tunnel lining material in situ, simplifies the construction process, reduces material transportation and processing, and improves construction efficiency. Due to the use of abandoned TBM excavation waste, the purchase cost of new materials is reduced, thereby reducing the construction cost. At the same time, the construction period of tunnel lining can be shortened, and the overall efficiency of engineering construction can be improved.

[0015] The following is a further description with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention is a structural schematic diagram of a concrete tunnel lining using TBM excavation waste in situ.

[0017] Figure numerals: 1-primary lining layer, 2-waterproof layer; 3-secondary lining layer. DETAILED DESCRIPTION Example 1

[0018] As shown in the figure, a concrete tunnel lining using TBM excavation waste in situ is provided. The tunnel lining is a multi-layer composite structure, which includes a primary lining layer 1, a waterproof layer 2 and a secondary lining layer 3 from the inside to the outside. The primary lining layer 1 is connected to the surrounding rock and is made of shotcrete prepared from TBM excavation sand and gravel. The waterproof layer 2 is made of a high-impermeability ECC material prepared from TBM excavation materials. The secondary lining layer 3 is made of a composite of a high-protective ECC material prepared from TBM excavation materials and a steel mesh.

[0019] The thickness ratio of the primary lining layer 1, the waterproof layer 2 and the secondary lining layer 3 is 1:0.2-0.5:2-4.

[0020] The primary lining layer 1 comprises, by weight, 300-360 parts of PO42.5 ordinary Portland cement, 180-220 parts of water, 40-80 parts of Class F II fly ash, 900-960 parts of TBM machine-made sand, 780-820 parts of crushed stone, 3.20-4.45 parts of naphthalene-based high-performance water reducer and 3.2-4.4 parts of silicate accelerator.

[0021] The machine-made sand is TBM excavation material with a particle size of less than 5 mm, and the crushed stone is TBM excavation material with a particle size of 5-10 mm.

[0022] The waterproof layer 2 comprises, by weight, 766-830 parts of PO42.5 ordinary Portland cement, 446-510 parts of Class F II fly ash, 383-510 parts of fine TBM sand, 383-510 parts of water, 10-17 parts of POM fibers and 0.8-1.5 parts of polycarboxylic acid powdered water reducing agent.

[0023] The particle size of the fine TBM sand material is less than 0.15 mm.

[0024] The waterproof layer 2 is connected to the primary lining layer 1 and is used to effectively prevent water from penetrating into the primary lining layer and the surrounding rock layer when water seepage occurs in the secondary lining layer. The waterproof layer 2 is characterized in that the fine aggregate used is fine TBM sand material with a particle size of less than 0.15 mm, which has excellent construction performance, self-compacting properties, crack resistance and impermeability, and has high bonding strength with the primary lining layer 1 and the secondary lining layer 3.

[0025] The second lining layer 3 comprises, by weight, 700-830 parts of cement, 446-575 parts of fly ash, 446-574 parts of fine TBM sand, 446-510 parts of water, 25-35 parts of PE fiber, 1-2.1 parts of polycarboxyl powdered thickener and 2.4-3.5 parts of polycarboxylic acid powdered water reducer.

[0026] The particle size of the fine TBM sand material is less than 0.15 mm.

[0027] The secondary lining 3 is connected to the waterproof layer 2 and is used for tunnel reinforcement and support. Its characteristic is that the fine aggregate used is fine TBM sand with a particle size of less than 0.15 mm, which has excellent strain hardening performance under load. Compared with the traditional concrete secondary lining structure, the high-protective ECC material prepared from TBM excavation material has excellent ductility, toughness, and impact and wear resistance. On the one hand, it can reduce the density of the steel mesh in the secondary lining, and on the other hand, it can effectively improve the tunnel's resistance to water erosion and deformation.

[0028] The present invention adopts in-situ recycling and processing of TBM tunnel excavation waste as aggregate for high-protection composite tunnel lining. The concrete aggregate obtained by recycling the TBM tunnel excavation material has the characteristics of high flake content and stone powder content. Therefore, the flaky rock is crushed and screened to obtain coarse aggregate for primary lining shotcrete. The fine aggregate obtained by crushing is mixed with the machine-made sand obtained by the primary screening in a certain proportion to obtain TBM machine-made sand with moderate particle grading and stone powder content for high-protection composite tunnel lining. The TBM tunnel excavation waste is converted into tunnel lining material, which avoids the generation and accumulation of a large amount of waste, realizes the effective recycling of resources, reduces the demand for the exploitation of natural resources, and reduces resource consumption.

[0029] The present invention adopts a composite lining structure, including a primary lining, a waterproof layer, a secondary lining, etc., to improve the overall protection capability of the tunnel. The waterproof layer can not only effectively block groundwater leakage, but also produce a certain deformation to release the stress of the surrounding rock and prevent the cracking of the secondary lining concrete; the primary lining adopts sprayed TBM aggregate concrete, which is prepared by recycled coarse aggregate with a particle size of 5mm-10mm and machine-made sand; the secondary lining adopts a fiber-reinforced cement-based composite material with high tensile strength and deformation capacity, which is prepared by TBM machine-made sand, and the application of the fiber-reinforced cement-based composite material to the secondary lining can reduce the reinforcement ratio of the secondary lining and simplify the construction process. Example 2

[0030] A method for preparing a concrete tunnel lining in situ using TBM excavation waste comprises the following steps: S1: Construction of primary lining 1, the specific process is: S11: Drying the excavated material from the TBM hole; S12: The dried TBM excavated material is screened according to the particle size into four parts: >10mm, 5-10mm, 0.15-5mm and <0.15mm; S13: crushing the TBM excavated material with a diameter of more than 10 mm in step S12, and screening the material into two parts with a particle size of 5-10 mm and less than 5 mm; S14: The 5-10 mm TBM hole excavation materials in step S12 and the 5-10 mm TBM hole excavation materials in step S13 are mixed in a weight ratio of 1:1-2 to obtain crushed stones for configuring the primary lining 1; S15: The TBM excavation materials of 0.15-5 mm and less than 5 mm in S12 are mixed in a weight ratio of 1:2-4 to obtain TBM machine-made sand for configuring the primary lining 1; S16: The crushed stone obtained in step S14 and the machine-made sand obtained in step S15 are mixed, by weight, with 288-450 parts of cement, 180 parts of water, 0-90 parts of fly ash, 845-1076 parts of machine-made sand, 689-913 parts of crushed stone and 3.6-5.2 parts of water reducing agent, and stirred for 2-4 minutes to prepare TBM hole excavation fine stone concrete for the primary lining layer 1; S17: The fine stone concrete obtained in step S16 is sprayed to obtain a primary lining layer 1; S2: Construction of waterproof layer 2, the specific process is: S21: The fine TBM sand with a diameter of less than 0.15 mm obtained in step S12 is mixed with 766-830 parts of cement, 383-510 parts of fine TBM sand and 446-510 parts of fly ash by weight for 1 minute, and after the three are evenly mixed, 383-510 parts of water and 0.8-1.5 parts of water reducer are added and stirred for 1 minute. After obtaining a uniform flowing slurry, 10-17 parts of POM fiber are added and stirred for 3 minutes to obtain a high impermeability ECC material; S22: After the primary lining layer 1 obtained in step S1 meets the construction conditions, pouring is performed by pumping to obtain a waterproof layer 2; S3: Construction of the second lining 3, the specific process is: S31: After the waterproof layer 2 obtained in step S2 meets the construction conditions, tie the steel mesh; S32: The fine TBM sand with a diameter of less than 0.15 mm obtained in step S12 is mixed with 700-830 parts of cement, 446-574 parts of fine TBM sand and 446-575 parts of fly ash by weight for 1 minute, and after the three are evenly mixed, 446-510 parts of water and 2.4-3.5 parts of water reducer are added and stirred for 30 seconds, and 1-2.1 parts of thickener are added and stirred for 1 minute, and after obtaining a uniform flowing slurry, 25-35 parts of PE fiber are added and stirred for 3 minutes, and finally a highly protective ECC material is obtained; S33: The highly protective ECC material obtained in step S32 is poured by pumping to finally obtain the second lining layer 3, thereby completing the preparation of the tunnel lining. Example 3

[0031] A method for preparing a concrete tunnel lining using TBM excavation waste in situ as described in Example 2 is adopted to prepare a concrete tunnel lining using TBM excavation waste in situ as described in Example 1, wherein the material components of the primary lining 1 are, by weight, 288 parts of cement, 180 parts of water, 45 parts of fly ash, 845 parts of TBM machine-made sand, 689 parts of crushed stone and 3.6 parts of water reducer; the material components of the waterproof layer 2 are, by weight, 830 parts of cement, 447 parts of fly ash, 383 parts of fine TBM sand, 383 parts of water, 10 parts of POM fiber and 0.8 parts of water reducer; the secondary lining 3 is prepared by 830 parts of cement, 446 parts of fly ash, 446 parts of fine TBM sand, 446 parts of water, 25 parts of PE fiber, 1.6 parts of thickener and 2.4 parts of water reducer. In the bending test, impermeability test, and impact and wear resistance test of the composite structure, the order of casting the specimens is to cast the primary lining 1 first, and then cast the waterproof layer 2 24 hours later. After the waterproof layer 2 is cast, the steel bars are tied in the mold 24 hours later, and then the secondary lining 3 is cast. The thickness ratio of the primary lining 1, waterproof layer 2, and secondary lining 3 along the specimen is 1:0.4:3. Example 4

[0032] A method for preparing a concrete tunnel lining using TBM excavation waste in situ as described in Example 2 is adopted to prepare a concrete tunnel lining using TBM excavation waste in situ as described in Example 1, wherein the material components of the primary lining 1 are, by weight, 450 parts of cement, 180 parts of water, 90 parts of fly ash, 1076 parts of TBM machine-made sand, 913 parts of crushed stone and 5.2 parts of water reducer; the material components of the waterproof layer 2 are, by weight, 766 parts of cement, 510 parts of fly ash, 510 parts of fine TBM sand, 510 parts of water, 17 parts of POM fiber and 1.5 parts of water reducer; the secondary lining 3 is prepared by 700 parts of cement, 574 parts of fly ash, 574 parts of fine TBM sand, 510 parts of water, 31 parts of PE fiber, 2.1 parts of thickener and 3.5 parts of water reducer. In the bending test, impermeability test, and impact and wear resistance test of the composite structure, the order of casting the specimens is to cast the primary lining 1 first, and then cast the waterproof layer 2 24 hours later. After the waterproof layer 2 is cast, the steel bars are tied in the mold 24 hours later, and then the secondary lining 3 is cast. The thickness ratio of the primary lining 1, waterproof layer 2, and secondary lining 3 along the specimen is 1:0.4:3.

[0033] At the same time, Comparative Examples 1 to 4 were carried out. In Comparative Examples 1 and 3, the preparation process of materials and composite lining specimens was the same as that of Examples 3 and 4. During the preparation process, the comparative examples used equal amounts of ordinary concrete coarse aggregate and machine-made sand to replace the TBM aggregate in the examples. Among them, the gradation of coarse and fine aggregates in the comparative examples was basically the same as that in the examples, and the slump was basically kept consistent by adjusting the amount of water reducer and thickener. The materials and components of the primary lining 1 (TBM tunnel excavation fine stone shotcrete), waterproof layer 2 (TBM tunnel excavation sand material high impermeability ECC) and secondary lining 3 (TBM tunnel excavation sand material high protective ECC) of Comparative Examples 1 to 4 and Examples 3 and 4 were tested for mechanical properties, and the results are as follows. Table 1 Test results of mechanical properties of materials and components of primary lining layer 1, waterproof layer 2 and secondary lining layer 3 in comparative examples 1 to 4 and embodiment 3 and embodiment 4

[0034]

[0035] As can be seen from Table 1, the primary lining concrete materials of Example 3 and Comparative Example 4 are close to those of the embodiment, but the flexural strength, ultimate deflection, impact and abrasion resistance, frost resistance and impermeability of the secondary lining and the composite structure are lower than those of the embodiment. This shows that the concrete lining prepared from TBM tunnel excavation waste has good protection and durability. By comparing Example 3 with Comparative Example 1, and Example 4 with Comparative Example 2, it can be seen that the concrete lining prepared from TBM tunnel excavation waste, the compressive strength, flexural strength, ultimate deflection, impermeability and impact and abrasion resistance of the primary lining, waterproof layer, secondary lining and composite structure are basically the same as those prepared from ordinary concrete coarse and fine aggregates; the concrete lining prepared from TBM tunnel excavation waste has good economic and environmental benefits.

[0036] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A concrete tunnel lining using in-situ TBM excavation waste, characterized in that: The tunnel lining is a multi-layer composite structure, which comprises, from the inside to the outside, a primary lining layer (1), a waterproof layer (2) and a secondary lining layer (3), wherein the primary lining layer (1) is connected to the surrounding rock and is made of shotcrete prepared from sand and gravel excavated from a TBM tunnel, the waterproof layer (2) is made of a highly impermeable ECC material prepared from TBM tunnel excavation materials, and the secondary lining layer (3) is made of a composite of a highly protective ECC material prepared from TBM tunnel excavation materials and a steel mesh.

2. The concrete tunnel lining using in-situ TBM excavation waste as claimed in claim 1, characterized in that: The thickness ratio of the primary lining layer (1), the waterproof layer (2) and the secondary lining layer (3) is 1:0.2-0.5:2-4.

3. The concrete tunnel lining using in-situ TBM excavation waste as claimed in claim 1, characterized in that: The primary lining (1) comprises, by weight, 300-360 parts of PO42.5 ordinary Portland cement, 180-220 parts of water, 40-80 parts of Class F II fly ash, 900-960 parts of TBM machine-made sand, 780-820 parts of crushed stone, 3.20-4.45 parts of naphthalene-based high-performance water-reducing agent and 3.2-4.4 parts of silicate accelerator.

4. The concrete tunnel lining using in-situ TBM excavation waste as claimed in claim 3, characterized in that: The machine-made sand is TBM excavation material with a particle size of less than 5 mm, and the crushed stone is TBM excavation material with a particle size of 5-10 mm.

5. The concrete tunnel lining using in-situ TBM excavation waste as claimed in claim 1, characterized in that: The waterproof layer (2) comprises, by weight, 766-830 parts of PO42.5 ordinary Portland cement, 446-510 parts of Class F II fly ash, 383-510 parts of fine TBM sand, 383-510 parts of water, 10-17 parts of POM fibers and 0.8-1.5 parts of polycarboxylic acid series powdered water reducing agent.

6. The concrete tunnel lining using in-situ TBM excavation waste as claimed in claim 5, characterized in that: The particle size of the fine TBM sand material is less than 0.15 mm.

7. The concrete tunnel lining using in-situ TBM excavation waste as claimed in claim 1, characterized in that: The second lining layer (3) comprises, by weight, 700-830 parts of cement, 446-575 parts of fly ash, 446-574 parts of fine TBM sand, 446-510 parts of water, 25-35 parts of PE fiber, 1-2.1 parts of polycarboxyl powdered thickener and 2.4-3.5 parts of polycarboxylic acid powdered water reducing agent.

8. The concrete tunnel lining using in-situ TBM excavation waste as claimed in claim 7, characterized in that: The particle size of the fine TBM sand material is less than 0.15 mm.

9. A method for preparing a concrete tunnel lining in situ using TBM excavation waste, characterized in that: The following steps are involved: S1: Construction of the primary lining (1), the specific process is as follows: S11: Drying the excavated material from the TBM hole; S12: The dried TBM excavated material is screened according to the particle size into four parts: >10mm, 5-10mm, 0.15-5mm and <0.15mm; S13: crushing the TBM excavated material with a diameter of more than 10 mm in step S12, and screening the material into two parts with a particle size of 5-10 mm and less than 5 mm; S14: mixing the 5-10 mm TBM excavation material in step S12 and the 5-10 mm TBM excavation material in step S13 in a weight ratio of 1:1-2 to obtain crushed stone for configuring the primary lining (1); S15: The TBM excavation materials of 0.15-5 mm and less than 5 mm in S12 are mixed in a weight ratio of 1:2-4 to obtain TBM machine-made sand for configuring the primary lining layer (1); S16: the crushed stone obtained in step S14 and the machine-made sand obtained in step S15 are mixed, in parts by weight, with 288-450 parts of cement, 180 parts of water, 0-90 parts of fly ash, 845-1076 parts of machine-made sand, 689-913 parts of crushed stone and 3.6-5.2 parts of a water reducing agent, and stirred for 2-4 minutes to prepare a TBM tunnel excavation fine stone concrete for the primary lining layer (1); S17: The fine stone concrete obtained in step S16 is sprayed to obtain a primary lining layer (1); S2: Construction of waterproof layer (2), the specific process is as follows: S21: The fine TBM sand with a diameter of less than 0.15 mm obtained in step S12 is mixed with 766-830 parts of cement, 383-510 parts of fine TBM sand and 446-510 parts of fly ash by weight for 1 minute, and after the three are evenly mixed, 383-510 parts of water and 0.8-1.5 parts of water reducer are added and stirred for 1 minute. After obtaining a uniform flowing slurry, 10-17 parts of POM fiber are added and stirred for 3 minutes to obtain a high impermeability ECC material; S22: After the primary lining layer (1) obtained in step S1 meets the construction conditions, pouring is performed by pumping to obtain a waterproof layer (2); S3: Construction of the second lining layer (3), the specific process is as follows: S31: After the waterproof layer (2) obtained in step S2 meets the construction conditions, tying the steel mesh; S32: The fine TBM sand with a diameter of less than 0.15 mm obtained in step S12 is mixed with 700-830 parts of cement, 446-574 parts of fine TBM sand and 446-575 parts of fly ash by weight for 1 minute, and after the three are evenly mixed, 446-510 parts of water and 2.4-3.5 parts of water reducer are added and stirred for 30 seconds, and 1-2.1 parts of thickener are added and stirred for 1 minute, and after obtaining a uniform flowing slurry, 25-35 parts of PE fiber are added and stirred for 3 minutes, and finally a highly protective ECC material is obtained; S33: The high-protective ECC material obtained in step S32 is poured by pumping to finally obtain a second lining layer (3), thereby completing the preparation of the tunnel lining.

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