Tunnel composite lining drainage system

Abstract

The invention discloses a tunnel composite lining drainage system, and relates to the technical field of tunnel engineering, a waterproof and drainage layer is arranged between a primary support and a secondary lining, a first side ditch and a second side ditch are respectively arranged on two sides of the bottom of a tunnel, the second side ditch is communicated with a central drainage ditch through a transverse drainage pipe, and the inner layer of the waterproof and drainage layer is a woodworking cloth layer. Drainage plates are evenly laid below the woodworking cloth layer, waterproof plates are connected between the drainage plates in a lap joint mode, annular blind pipes are arranged in the middles of the drainage plates, longitudinal blind pipes are embedded into the bottoms of the drainage plates and the bottoms of the annular blind pipes, and the longitudinal blind pipes are communicated with the first side ditch; the secondary lining construction joint is provided with a middle-buried type water stop belt, and the positions, on the two sides of the middle-buried type water stop belt, of the construction joint are filled with water stop sealing materials. And the construction joints are filled with high-elasticity water stop sealing materials, the sealing performance is high, the failure probability of the water stop belt can be reduced, and the waterproof and drainage effects are improved.

Description

Technical Field

[0001] The invention relates to the technical field of waterproof construction of municipal tunnel engineering, in particular to a tunnel composite lining drainage system. Background Art

[0002] The waterproof design of railway tunnels is based on the principle of "combining prevention, drainage, interception and blocking, adapting to local conditions and comprehensive management". The waterproof and drainage measures commonly used in the existing technology are: First, the circumferential drainage blind pipe, longitudinal drainage blind pipe, transverse drainage blind pipe, drainage ditch or central ditch on both sides of the tunnel form a complete drainage system. A large number of seepage holes are set on the upper part of the longitudinal drainage blind pipe. The groundwater discharged from the circumferential drainage blind pipe and the drainage cushion layer enters the water seepage port, gathers in the longitudinal drainage blind pipe, and then is discharged into the central ditch by the transverse drainage blind pipe and finally discharged out of the tunnel. Second, during the construction of composite lining, sprayed concrete or waterproof concrete is used to prevent groundwater from seeping in. In addition, waterproof membranes or waterproof boards and carpentry cloth are laid between the initial support and the secondary lining to form a waterproof system. Third, waterproof construction at construction joints and expansion joints. Construction joints mainly refer to those produced during tunnel lining concrete. Expansion joints are expansion joints set up to prevent lining cracks caused by temperature changes or concrete shrinkage. Construction joints and expansion joints are generally waterproofed with external or embedded waterstops, and EPDM rubber waterstops are commonly used.

[0003] At present, the main problems with the above-mentioned drainage system are: 1. As the tunnel's operating years increase, groundwater and sediment leaking from the tunnel lining enter the drainage system together, causing blockage of blind pipes; 2. Cracking and failure of water stop strips at deformation joints can also cause tunnel seepage and leakage, and are difficult to repair. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a tunnel composite lining drainage system to address the deficiencies in the prior art, which can reduce the blockage of annular blind pipes, and the construction joints are filled with highly elastic water-stop sealing materials with strong sealing properties, which can reduce the probability of failure of the waterstop belt and increase the drainage effect.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A tunnel composite lining drainage system, wherein a drainage prevention layer is arranged between an initial support and a secondary lining, a side ditch 1 and a side ditch 2 are arranged on both sides of the tunnel bottom respectively, the side ditch 2 is connected to a central drainage ditch through a transverse drainage pipe, the inner layer of the drainage prevention layer is a carpentry cloth layer, drainage boards are evenly laid under the carpentry cloth layer, waterproof boards are overlapped between the drainage boards, an annular blind pipe is arranged in the middle of the drainage board, a longitudinal blind pipe is embedded in the bottom of the drainage board and the annular blind pipe, and the longitudinal blind pipe is connected to the side ditch 1; an embedded waterstop is arranged at the construction joint of the secondary lining, and water-stop sealing materials are filled in the construction joints on both sides of the embedded waterstop.

[0006] Furthermore, an overflow pipe is arranged at the bottom of the central drainage ditch, and the overflow pipe extends to the inverted arch waterproof layer.

[0007] Furthermore, the drainage boards are evenly laid in a circular pattern along the longitudinal direction of the tunnel, with a laying interval of 4-5m.

[0008] Furthermore, the drainage board is a convex shell type drainage board.

[0009] Furthermore, the water-stop sealing material is a high-elastic sealing material, which is mixed with a main agent and a curing agent in a weight ratio of 10:1. The main agent is made of the following raw materials in parts by weight: 30 parts of base glue, 18-23 parts of diisodecyl phthalate, 28-33 parts of nano-calcium carbonate, 12-15 parts of montmorillonite, 1.5-2.2 parts of polyamide wax, and 1.5-2 parts of dewatering agent; the curing agent is made of the following raw materials in parts by weight: 7-9 parts of dibutyltin dilaurate, 2.0-2.4 parts of tetramethylammonium hydroxide, 24-30 parts of diisodecyl phthalate, and 60-65 parts of heavy calcium carbonate.

[0010] Furthermore, the base glue is prepared by the following steps: (1) Vinyl trimethoxysilane and di-tert-butyl peroxide are mixed and reacted at 110°C for 50 hours to obtain a silane polymer; (2) After the silane polymer and ethanol are evenly mixed, the terminal silane-modified polyether resin is added and stirred at room temperature for 20 minutes to obtain a base glue; The weight ratio of the di-tert-butyl peroxide, vinyl trimethoxysilane, ethanol and terminal silane-modified polyether resin is 1:40:100:100-120.

[0011] Furthermore, methyltrimethoxysilane is also added in step (2), and the weight ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 1:8-10.

[0012] The beneficial effects of the present invention are: The present application discloses a tunnel composite lining drainage system, which achieves excellent drainage effect through the construction of a drainage layer and a waterproof design of a construction joint.

[0013] Two tunnel side ditches are set on both sides of the tunnel bottom, and the water in the drainage layer and the water in the tunnel arch and wall are directly discharged through the side ditch one; if the groundwater pressure is relatively high and passes through the initial support of the invert arch and the waterproof layer, and the central drainage ditch cannot drain the water in time, it can overflow through the horizontal drainage pipe to the side ditch two for discharge, thereby increasing the tunnel drainage effect and ensuring the safety and stability of the tunnel.

[0014] The drainage layer uses wood cloth + drainage board drainage facilities, in which the drainage board uses a convex shell drainage board, which is evenly laid in a circular shape along the longitudinal direction of the tunnel with a width of 90cm. An annular blind pipe is set in the middle of the convex shell drainage board. The two sides of the drainage board are about 15cm flat plates for overlapping waterproof boards. The concave surface is fixed during the construction of the second lining, and the convex surface is close to the geotextile and the initial support. The drainage board is laid near the construction joint to form a drainage channel, which can timely discharge the water leaking from the initial support, reduce the water pressure at the construction joint of the second lining, and ensure the waterproof function. Through the composite drainage of the drainage board and the annular blind pipe, the water containing particulate matter leaking from the initial support is drained through the initial filtration of the geotextile and the drainage board, which greatly reduces the possibility of blockage of the annular blind pipe. In addition, the drainage board and the annular blind pipe have a strong drainage capacity.

[0015] 2. The secondary lining construction joint adopts a buried waterstop, specifically a water-expanding rubber waterstop, and The construction joints on both sides are filled with water-stopping sealing materials, wherein the water-stopping sealing materials are made of highly elastic materials, which are silane-modified polyether resin and silane polymer double cross-linked resin as the base glue, wherein vinyl trimethoxysilane is polymerized by free radicals to form silane polymer, which has good miscibility with silane-modified polyether resin and can be evenly distributed. After mixing with the curing agent, the silane polymer undergoes hydrolysis-polymerization under the action of a small amount of tetramethylammonium hydroxide and external water vapor, and forms an interpenetrating double cross-linked network structure with the silane-modified polyether resin gel, and contacts with the hydrophilic groups on the water-swelling rubber waterstop, and the water-swelling rubber waterstop expands, forming an integral waterproof system with the water-stopping sealing materials on both sides, with good waterproof effect, and the sealing material has strong elastic deformation and elastic recovery properties, not only with strong sealing, but also with strong recovery and long-term stability.

[0016] Adding a small amount of methyltrimethoxysilane to the silane polymer can not only undergo hydrolysis-condensation with the side chain groups on the silane polymer, but also cross-link with the silane-modified polyether end groups. In addition, its methyl functional groups are evenly dispersed in the silane polymer to avoid agglomeration of the silane polymer, which helps to further increase the elastic recovery performance, thereby achieving strong sealing stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of this application; Figure 2 for Figure 1 Partial longitudinal section.

[0018] In the figure: 1-initial support, 2-secondary lining, 3-side ditch one, 4-side ditch two, 5-central drainage ditch, 6-carpentry cloth layer, 7-drainage board, 8-waterproof board, 9-transverse drainage pipe, 10-annular blind pipe, 11-longitudinal blind pipe, 12-buried waterstop, 13-waterstop sealing material. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with specific implementation methods. Example 1

[0020] A tunnel composite lining drainage system, see Figure 1 and Figure 2 As shown, a waterproof and drainage layer is laid between the initial support 1 and the secondary lining 2, and side ditches 1 3 and 2 4 are respectively arranged on both sides of the tunnel bottom. The side ditches 2 4 are connected to the central drainage ditch 5 through a transverse drainage pipe 9. The inner layer of the waterproof and drainage layer is a wood cloth layer 6. Drainage boards 7 are evenly laid under the wood cloth layer 6. The drainage boards 7 are convex shell-type drainage boards with a width of 90 cm. 15 cm on both sides are flat lap waterproof boards 8. The distribution spacing of the drainage boards 7 is 5 m. An annular blind pipe 10 is arranged in the middle of the drainage board 7, wherein a hole is opened on the upper part of the longitudinal blind pipe 11, and the bottoms of the drainage board 7 and the annular blind pipe 10 are embedded in the opening of the longitudinal blind pipe 11, and the longitudinal blind pipe 11 is connected to the side ditch 1 3; an overflow pipe 14 is arranged at the bottom of the central drainage ditch 5, and the overflow pipe 14 extends to the inverted arch waterproof layer.

[0021] An embedded waterstop 12 is provided at the construction joint of the secondary lining 2 , wherein the embedded waterstop in the present application is a water-swellable rubber waterstop, and the construction joints on both sides of the embedded waterstop 12 are filled with water-stop sealing material 13 .

[0022] The water-stop sealing material 13 is a high-elastic sealing material, which is mixed with a main agent and a curing agent in a weight ratio of 10:1. The main agent is made of the following raw materials in parts by weight: 30 parts of base glue, 18 parts of diisodecyl phthalate, 28 parts of nano calcium carbonate, 15 parts of montmorillonite, 1.5 parts of polyamide wax, and 1.5 parts of dewatering agent (AOS sealant dewatering agent); the curing agent is made of the following raw materials in parts by weight: 7 parts of dibutyl dilaurate, 2 parts of tetramethylammonium hydroxide, 30 parts of diisodecyl phthalate, and 60 parts of heavy calcium carbonate.

[0023] The base glue is prepared by the following steps: (1) Vinyl trimethoxysilane and di-tert-butyl peroxide (DTBP) were mixed and reacted at 110°C for 50 hours to obtain a silane polymer; (2) After the silane polymer and ethanol are evenly mixed, add the terminal silane modified polyether resin (Senfida, silane terminated polyether resin), stir at room temperature for 20 minutes to obtain the base glue; The weight ratio of di-tert-butyl peroxide, vinyl trimethoxysilane, ethanol and terminal silane-modified polyether resin is 1:40:100:100.

[0024] Methyltrimethoxysilane is also added in step (2), and the weight ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 1:8. Example 2

[0025] The water-stop sealing material 13 is a high-elastic sealing material, which is mixed with a main agent and a curing agent in a weight ratio of 10:1. The main agent is made of the following raw materials in parts by weight: 30 parts of base glue, 19 parts of diisodecyl phthalate, 29 parts of nano calcium carbonate, 14 parts of montmorillonite, 1.6 parts of polyamide wax, and 1.6 parts of dewatering agent; the curing agent is made of the following raw materials in parts by weight: 7.5 parts of dibutyltin dilaurate, 2.2 parts of tetramethylammonium hydroxide, 28 parts of diisodecyl phthalate, and 62 parts of heavy calcium carbonate.

[0026] The base glue is prepared by the following steps: (1) Vinyl trimethoxysilane and di-tert-butyl peroxide (DTBP) were mixed and reacted at 110°C for 50 hours to obtain a silane polymer; (2) After the silane polymer and ethanol are evenly mixed, the terminal silane-modified polyether resin is added and stirred at room temperature for 20 minutes to obtain a base glue; The weight ratio of di-tert-butyl peroxide, vinyl trimethoxysilane, ethanol and terminal silane-modified polyether resin is 1:40:100:105.

[0027] Methyltrimethoxysilane is also added in step (2), and the weight ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 1:9. Example 3

[0028] The water-stop sealing material 13 is a high-elastic sealing material, which is mixed with a main agent and a curing agent in a weight ratio of 10:1. The main agent is made of the following raw materials in parts by weight: 30 parts of base glue, 20 parts of diisodecyl phthalate, 30 parts of nano-calcium carbonate, 13 parts of montmorillonite, 1.8 parts of polyamide wax, and 1.8 parts of dewatering agent; the curing agent is made of the following raw materials in parts by weight: 8 parts of dibutyltin dilaurate, 2.3 parts of tetramethylammonium hydroxide, 26 parts of diisodecyl phthalate, and 64 parts of heavy calcium carbonate.

[0029] The base glue is prepared by the following steps: (1) Vinyl trimethoxysilane and di-tert-butyl peroxide (DTBP) were mixed and reacted at 110°C for 50 hours to obtain a silane polymer; (2) After the silane polymer and ethanol are evenly mixed, the terminal silane-modified polyether resin is added and stirred at room temperature for 20 minutes to obtain a base glue; The weight ratio of di-tert-butyl peroxide, vinyl trimethoxysilane, ethanol and terminal silane-modified polyether resin is 1:40:100:110.

[0030] In step (2), methyltrimethoxysilane is also added, and the weight ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 1:9.5. Example 4

[0031] The water-stop sealing material 13 is a high-elastic sealing material, which is mixed with a main agent and a curing agent in a weight ratio of 10:1. The main agent is made of the following raw materials in parts by weight: 30 parts of base glue, 23 parts of diisodecyl phthalate, 33 parts of nano calcium carbonate, 12 parts of montmorillonite, 2.2 parts of polyamide wax, and 2 parts of dewatering agent; the curing agent is made of the following raw materials in parts by weight: 9 parts of dibutyltin dilaurate, 2.4 parts of tetramethylammonium hydroxide, 24 parts of diisodecyl phthalate, and 65 parts of heavy calcium carbonate.

[0032] The base glue is prepared by the following steps: (1) Vinyl trimethoxysilane and di-tert-butyl peroxide (DTBP) were mixed and reacted at 110°C for 50 hours to obtain a silane polymer; (2) After the silane polymer and ethanol are evenly mixed, the terminal silane-modified polyether resin is added and stirred at room temperature for 20 minutes to obtain a base glue; The weight ratio of di-tert-butyl peroxide, vinyl trimethoxysilane, ethanol and terminal silane-modified polyether resin is 1:40:100:120. Methyl trimethoxysilane is also added in step (2), and the weight ratio of methyl trimethoxysilane to vinyl trimethoxysilane is 1:10.

[0033] Comparative Example 1 Comparative Example 1 is a comparative example of Example 4, except that the montmorillonite in Comparative Example 1 is replaced by nano calcium carbonate.

[0034] Comparative Example 2 The difference between Comparative Example 2 and Example 4 is that: The base rubber is terminal silane-modified polyether resin (Zhonghua MS).

[0035] Comparative Example 3 In Comparative Example 3, no montmorillonite was added.

[0036] Performance Testing The sealing materials prepared in Examples 1-4 and Comparative Examples 1-3 were tested for extrusion performance (GB / T 13477.3-2002), tensile modulus (GB / T 528-2009), tensile strength, elongation at break and elastic recovery rate (GB / T13477.17-2017 Test Methods for Building Sealing Materials), tensile bond strength (GB / T13477.8), fixed elongation adhesion, fixed elongation adhesion after immersion in water, and adhesion after cold drawing and hot pressing (JC / T 881-2017 Building Sealant for Concrete Joints). The test results are shown in Table 1.

[0037] Table 1 Performance test results

[0038] The surface drying time of the sealing materials prepared in Examples 1-4 of the present application is 40-50min, and the fixed stretch adhesion, fixed stretch adhesion after immersion in water, and adhesion after cold drawing and hot pressing are all non-destructive, and the modulus is low, the mechanical properties are excellent, and the elastic recovery rate is excellent. Therefore, it can adapt to the structural deformation at the construction joint, and has excellent plasticity, adhesion and waterproofness, which helps to increase the waterproof performance of the waterproof layer of the present application. Combined with the data of Comparative Example 1, it can be seen that the composite filler has a certain effect on the extrudability, but significantly improves the elongation at break and the mechanical properties of the joint material. From the data of Comparative Example 2, it can be seen that the introduction of a certain amount of silane polymer into the silane-modified polyether resin can greatly improve the elongation at break and the elastic recovery rate of the joint material; in addition, the introduction of montmorillonite can improve the elastic recovery rate of the joint material to a certain extent. The water-stop sealing material used in the present application is a silane polymer that undergoes hydrolysis-polymerization under the action of a small amount of tetramethylammonium hydroxide and external water vapor, forming an interpenetrating double-cross-linked network structure with the silane-modified polyether resin gel. It has good elasticity and a high elastic recovery rate. In the process of curing, it is tightly bonded to the water-swelling rubber waterstop and concrete, and has excellent sealing and waterproof properties. It can form a second waterproof barrier between the initial support and the secondary lining, greatly increasing the waterproofing effect and stability.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in the field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A tunnel composite lining drainage system, wherein a drainage layer is provided between the primary support (1) and the secondary lining (2), characterized in that: Side ditch 1 (3) and side ditch 2 (4) are respectively arranged on both sides of the tunnel bottom. Side ditch 2 (4) is connected to the central drainage ditch (5) through a transverse drainage pipe (9). The inner layer of the drainage layer is a woodworking cloth layer (6). Drainage boards (7) are evenly laid below the woodworking cloth layer (6). Waterproof boards (8) are overlapped between the drainage boards (7). An annular blind pipe (10) is arranged in the middle of the drainage board (7). The bottoms of the drainage board (7) and the annular blind pipe (10) are embedded with a longitudinal blind pipe (11). The longitudinal blind pipe (11) is connected to the side ditch 1 (3). A buried waterstop (12) is arranged at the construction joint of the secondary lining (2). Waterstop sealing material (13) is filled in the construction joints on both sides of the buried waterstop (12).

2. A tunnel composite lining drainage system according to claim 1, characterized in that: An overflow pipe (14) is arranged at the bottom of the central drainage ditch (5), and the overflow pipe (14) extends to the inverted arch waterproof layer.

3. A tunnel composite lining drainage system according to claim 1, characterized in that: The drainage boards (7) are evenly laid in a circular pattern along the longitudinal direction of the tunnel, with a laying interval of 4-5 m.

4. The tunnel composite lining drainage system according to claim 1, characterized in that: The drainage board (7) is a convex shell type drainage board.

5. The tunnel composite lining drainage system according to claim 1, characterized in that: The water-stop sealing material (13) is a high-elastic sealing material, which is prepared by mixing a main agent and a curing agent in a weight ratio of 10:

1. The main agent is prepared from the following raw materials in parts by weight: 30 parts of base glue, 18-23 parts of diisodecyl phthalate, 28-33 parts of nano calcium carbonate, 12-15 parts of montmorillonite, 1.5-2.2 parts of polyamide wax, and 1.5-2 parts of dewatering agent; the curing agent is prepared from the following raw materials in parts by weight: 7-9 parts of dibutyltin dilaurate, 2.0-2.4 parts of tetramethylammonium hydroxide, 24-30 parts of diisodecyl phthalate, and 60-65 parts of heavy calcium carbonate.

6. A tunnel composite lining drainage system according to claim 5, characterized in that: The base glue is prepared by the following steps: (1) Vinyl trimethoxysilane and di-tert-butyl peroxide are mixed and reacted at 110°C for 50 hours to obtain a silane polymer; (2) After the silane polymer and ethanol are evenly mixed, the terminal silane-modified polyether resin is added and stirred at room temperature for 20 minutes to obtain a base glue; The weight ratio of the di-tert-butyl peroxide, vinyl trimethoxysilane, ethanol and terminal silane-modified polyether resin is 1:40:100:100-120.

7. A tunnel composite lining drainage system according to claim 6, characterized in that: In the step (2), methyltrimethoxysilane is also added, and the weight ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 1:8-10.

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