Repair material for water leakage of tunnel in plateau alpine region and preparation method of repair material

Abstract

The invention discloses a repairing material for water leakage of a tunnel in a plateau alpine region and a preparation method. The repairing material is prepared from the following components in parts by weight: 80 to 120 parts of superfine cement, 30 to 50 parts of compatilizer, 20 to 30 parts of hydroxylated epoxidized soybean oil modified polyurethane prepolymer, 10 to 20 parts of waterborne epoxy resin, 10 to 20 parts of metakaolin, 10 to 15 parts of sodium silicate and 10 to 15 parts of curing agent. The hydroxylated epoxidized soybean oil is introduced into the polyurethane prepolymer, so that on one hand, the compatibility between the polyurethane prepolymer and cement is enhanced; on the other hand, by controlling the dosage of the hydroxylated epoxidized soybean oil modified polyurethane prepolymer and the cement and controlling the content of NCO in the hydroxylated epoxidized soybean oil modified polyurethane prepolymer, the reaction between epoxy groups and isocyanato can be inerted at normal temperature, and the storage stability of the system is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel crack repair, and more particularly to a repair material for tunnel water leakage in high altitude and cold regions and a preparation method thereof. Background Art

[0002] A large number of railway tunnels in cold regions are plagued by problems such as lining cracking and leakage, roadbed seepage, slurry overflow, lining ice hanging, structural frost heaving and falling blocks, and ditch ice blockage, which have emerged in an endless stream and seriously affected the safe operation of the railway.

[0003] According to a large number of research and survey results, the causes of water seepage and frost damage in tunnels in high-altitude and cold areas, as well as the temperature field distribution, are significantly different from those in tunnels in general areas, and the disease characteristics they present are also different. Domestic and foreign scholars have conducted a large number of studies on the causes of tunnels in high-altitude and cold areas, anti-freezing technology, and maintenance and repair technology systems.

[0004] In terms of the causes of tunnel leakage and frost damage in high-altitude and cold areas, when the tunnel passes through aquifers, the inherent groundwater channel is cut off, and the space in the tunnel itself becomes a good place for groundwater to gather. Tunnels in such an environment are prone to leakage due to various reasons such as poor geological environment, structural defects, poor construction, and poor operation and maintenance. After tunnel excavation under high-altitude and cold conditions, the original stable thermal conditions in the permafrost area are destroyed, the original surrounding rock seepage field and temperature field change, and there will be freeze-thaw cycles of varying degrees around the tunnel lining. There is a temperature difference between the water temperature and the frozen surrounding rock, and the temperature is exchanged, and the water temperature drops and freezes; at the same time, driven by the train piston wind and natural wind, the cold air outside the tunnel enters the tunnel, and convective heat exchange occurs with the second lining, causing the low temperature to enter the drainage system behind the second lining, thereby causing the internal temperature of the drainage system to drop. As the water temperature gradually drops below zero, ice forms and blocks the drainage system. Water accumulates behind the lining and freezes and swells, squeezing the lining structure and even causing it to crack. It is also very easy for the lining structure to leak into the tunnel through joints or cracks in the tunnel lining or base arch.

[0005] In terms of antifreeze technology in high-cold plateau areas, domestic and foreign researchers mainly focus on antifreeze technology, temperature field and frost heave mechanism. Antifreeze technology for tunnel structure and drainage system in cold regions can be divided into two aspects: "active" and "passive". Active antifreeze and operation and maintenance technology are mostly used in highway and municipal tunnel projects. For example, geothermal and auxiliary electric heating are used to heat up the environment in the tunnel, and the cost of investment in remediation is very staggering. Active antifreeze and operation and maintenance technology are rarely used in railway tunnel projects. At present, electric heating technology is used in the side ditches of the Qilianshan Tunnel of the Lanzhou-Xinjiang Passenger Railway and the Aimin Tunnel of the Harbin-Mudanjiang Passenger Railway to achieve the purpose of antifreeze of the ditch. Passive antifreeze and operation and maintenance technology are widely used in all walks of life. The typical technical means in cold-region railway tunnels are to add a thermal insulation layer between the primary support and the secondary lining, set up a central deep buried ditch, thermal insulation side ditch, thermal insulation inspection well, cold-proof drainage tunnel, and build thermal insulation type tunnel openings. Due to the operation of high-speed trains and the limitation of skylight time, it is difficult to carry out anti-cold and anti-freeze treatment on the secondary lining surface of railway tunnels, and the current technical means have not completely solved the problem of frost damage.

[0006] In terms of water leakage control technology in plateau and cold regions, it is mainly based on the control principle of "blocking, draining and intercepting", and uses grouting to seal, grooving and burying pipes for drainage, surface water interception and other methods for control. A series of grouting water blocking materials and processes have also been formed, but there is insufficient research on material properties, grouting timing, grouting pressure and complete sets of processes, and it is mainly aimed at tunnels in general areas. There is insufficient scientific guidance for the control of water leakage in tunnels in plateau and cold regions, and the cause mechanism of water leakage and frost damage in tunnels in plateau and cold regions has not been fully explored. There is a lack of systematic research on the temperature field distribution characteristics of tunnels in plateau and cold regions, and there is a lack of long-term control technology for diseases such as mud boiling, lining leakage, and frost heave under freeze-thaw cycles. In particular, the negative temperature and wet temperature sensitivity of traditional control materials in the complex environment of the plateau and cold regions are prominent, which affects the control effect. The leakage location and characteristics have not been distinguished, and it is difficult to achieve long-term control.

[0007] Therefore, how to provide a repair material and preparation method for tunnel water leakage in plateau and cold areas, which can achieve efficient and timely treatment of water leakage problems and eliminate safety hazards in tunnels is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0008] In view of this, the present invention provides a repair material and a preparation method for tunnel water leakage in plateau and cold areas, which can reduce the problems of low initial strength and poor freeze-thaw resistance of traditional repair materials.

[0009] In order to achieve the above object, the present invention adopts the following technical solution:

[0010] A repair material for tunnel water seepage in plateau and cold regions comprises the following components in parts by weight: 80-120 parts of ultrafine cement, 30-50 parts of a compatibilizer, 20-30 parts of a hydroxylated epoxy soybean oil-modified polyurethane prepolymer, 10-20 parts of a water-based epoxy resin, 10-20 parts of metakaolin, 10-15 parts of sodium silicate and 10-15 parts of a curing agent.

[0011] Preferably, the NCO content of the hydroxylated epoxy soybean oil modified polyurethane prepolymer is 7-9%.

[0012] Preferably, the hydroxylated epoxy soybean oil modified polyurethane prepolymer is prepared by the following method:

[0013] (1) Add polyethylene glycol to a reaction kettle, perform vacuum dehydration at 112-115° C. for 1-2 hours, add isophorone diisocyanate when the temperature drops to 45-55° C., then slowly raise the temperature to 70-80° C. and react for 2-3 hours;

[0014] (2) The temperature of the material in (1) is lowered by 40-45° C., a catalyst is added, the temperature is slowly raised to 70-80° C., hydroxylated epoxy soybean oil is added dropwise, and the reaction is stopped when the NCO content is 7%-9%, thereby obtaining a hydroxylated epoxy soybean oil-modified polyurethane prepolymer.

[0015] Preferably, the molar ratio of the polyethylene glycol to isophorone diisocyanate is 1:2.

[0016] Preferably, the catalyst is dibutyltin dilaurate.

[0017] Preferably, the amount of the catalyst is 0.02-0.03% of the sum of the mass of polyethylene glycol and isophorone diisocyanate.

[0018] Preferably, the model of the water-based epoxy resin is CYDW-100.

[0019] Preferably, the compatibilizer is a mixture of heavy aromatics and alkanes in a mass ratio of 1:(1-2); the heavy aromatics include D100# or D120#; and the alkanes include n-butane or hexane.

[0020] Preferably, the curing agent is a ketimine curing agent.

[0021] Another object of the present invention is to provide a method for preparing the above-mentioned repair material for tunnel leakage in plateau and cold regions, comprising the following steps:

[0022] a. Add ultrafine cement and metakaolin into a mixer, stir and mix, then add compatibilizer and water, and stir for 3-5 minutes;

[0023] b. Add hydroxylated epoxy soybean oil modified polyurethane prepolymer and water-based epoxy resin, continue stirring for 2-3 minutes, add sodium silicate and curing agent, stir evenly, and the repair material can be obtained.

[0024] It can be seen from the above technical solution that compared with the prior art, the present invention has the following beneficial effects:

[0025] The present application introduces hydroxylated epoxy soybean oil into the polyurethane prepolymer, which enhances the compatibility between the polyurethane prepolymer and cement on the one hand; on the other hand, by controlling the amount of hydroxylated epoxy soybean oil-modified polyurethane prepolymer and cement, and controlling the NCO content in the hydroxylated epoxy soybean oil-modified polyurethane prepolymer, the reaction between the epoxy group and the isocyanate group can be inertized at room temperature, thereby enhancing the storage stability of the system. Furthermore, after the exothermic reaction between the added water and the isocyanate group, the reaction between the epoxy group and the isocyanate group is smoothly activated, so that the cement can quickly complete the initial curing in a humid state, and with the cooperation of each component, an excellent network structure is smoothly formed in the system, which not only makes the repair material have good early strength, but also can enhance the adhesion between the cold patching liquid and the aggregate, and also effectively improves the problem of poor freeze-thaw resistance of the repair material caused by poor water damage resistance during the subsequent use of the polyurethane material.

[0026] The introduction of sodium silicate inorganic substance promotes the organic-inorganic hybrid reaction between hydroxylated epoxy soybean oil modified polyurethane prepolymer and sodium silicate inorganic substance, absorbs a large number of bubbles generated when the polyurethane material comes into contact with water, and avoids the problem of large porosity due to the presence of a large number of bubbles in the mixture during production and application, making it difficult to compact during on-site construction and causing secondary bulging after compaction. At the same time, controlling the porosity and density of cold patch asphalt after molding can also increase the freeze-thaw resistance of the repair material during later use. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] This embodiment provides a repair material for tunnel leakage in plateau and cold regions, comprising the following components by weight: 120 parts of ultrafine cement, 30 parts of a compatibilizer, 30 parts of a hydroxylated epoxy soybean oil-modified polyurethane prepolymer, 10 parts of a water-based epoxy resin, 20 parts of metakaolin, 10 parts of sodium silicate, and 15 parts of a curing agent;

[0030] In this embodiment, the NCO content of the hydroxylated epoxy soybean oil modified polyurethane prepolymer is 7%.

[0031] The hydroxylated epoxy soybean oil modified polyurethane prepolymer was prepared by the following method:

[0032] (1) Add polyethylene glycol to a reaction kettle, perform vacuum dehydration at 115°C for 1 hour, add isophorone diisocyanate when the temperature drops to 55°C, then slowly raise the temperature to 70°C and react for 3 hours;

[0033] (2) The temperature of the material in (1) was lowered by 40°C, a catalyst was added, the temperature was slowly raised to 80°C, hydroxylated epoxy soybean oil was added dropwise, and the reaction was stopped when the NCO content reached 7%, thereby obtaining a hydroxylated epoxy soybean oil modified polyurethane prepolymer.

[0034] The molar ratio of polyethylene glycol to isophorone diisocyanate is 1:2.

[0035] The catalyst is dibutyltin dilaurate.

[0036] The amount of the catalyst used is 0.03% of the sum of the mass of polyethylene glycol and isophorone diisocyanate.

[0037] The model of water-based epoxy resin is CYDW-100.

[0038] The compatibilizer is a mixture of heavy aromatics and alkanes in a mass ratio of 1:1; the heavy aromatics is D100#; and the alkane is hexane.

[0039] The curing agent is a ketimine curing agent.

[0040] Example 2

[0041] This embodiment provides a repair material for tunnel leakage in plateau and cold regions, comprising the following components by weight: 80 parts of ultrafine cement, 50 parts of compatibilizer, 20 parts of hydroxylated epoxy soybean oil modified polyurethane prepolymer, 20 parts of water-based epoxy resin, 10 parts of metakaolin, 15 parts of sodium silicate, and 10 parts of curing agent;

[0042] In this embodiment, the NCO content of the hydroxylated epoxy soybean oil modified polyurethane prepolymer is 9%.

[0043] The hydroxylated epoxy soybean oil modified polyurethane prepolymer was prepared by the following method:

[0044] (1) Add polyethylene glycol to a reaction kettle, perform vacuum dehydration at 112°C for 2 hours, add isophorone diisocyanate when the temperature drops to 45°C, then slowly raise the temperature to 80°C and react for 2 hours;

[0045] (2) The temperature of the material in (1) was lowered by 45° C., a catalyst was added, the temperature was slowly raised to 70° C., hydroxylated epoxy soybean oil was added dropwise, and the reaction was stopped when the NCO content reached 9%, thereby obtaining a hydroxylated epoxy soybean oil-modified polyurethane prepolymer.

[0046] The molar ratio of polyethylene glycol to isophorone diisocyanate is 1:2.

[0047] The catalyst is dibutyltin dilaurate.

[0048] The amount of the catalyst used is 0.02% of the sum of the mass of polyethylene glycol and isophorone diisocyanate.

[0049] The model of water-based epoxy resin is CYDW-100.

[0050] The compatibilizer is a mixture of heavy aromatics and alkanes in a mass ratio of 1:2; the heavy aromatics is D120#; and the alkane is n-butane.

[0051] The curing agent is a ketimine curing agent.

[0052] Example 3

[0053] This embodiment provides a repair material for tunnel leakage in plateau and cold regions, comprising the following components in parts by weight: 100 parts of ultrafine cement, 40 parts of a compatibilizer, 25 parts of a hydroxylated epoxy soybean oil-modified polyurethane prepolymer, 15 parts of a water-based epoxy resin, 150 parts of metakaolin, 13 parts of sodium silicate, and 13 parts of a curing agent;

[0054] In this embodiment, the NCO content of the hydroxylated epoxy soybean oil modified polyurethane prepolymer is 8%.

[0055] The hydroxylated epoxy soybean oil modified polyurethane prepolymer was prepared by the following method:

[0056] (1) Add polyethylene glycol to a reaction kettle, perform vacuum dehydration at 113°C for 1.5 hours, add isophorone diisocyanate when the temperature drops to 50°C, then slowly raise the temperature to 75°C and react for 2.5 hours;

[0057] (2) The temperature of the material in (1) was lowered by 43° C., a catalyst was added, the temperature was slowly raised to 75° C., hydroxylated epoxy soybean oil was added dropwise, and the reaction was stopped when the NCO content reached 8%, thereby obtaining a hydroxylated epoxy soybean oil-modified polyurethane prepolymer.

[0058] The molar ratio of polyethylene glycol to isophorone diisocyanate is 1:2.

[0059] The catalyst is dibutyltin dilaurate.

[0060] The amount of the catalyst used is 0.02% of the sum of the mass of polyethylene glycol and isophorone diisocyanate.

[0061] The model of water-based epoxy resin is CYDW-100.

[0062] The compatibilizer is a mixture of heavy aromatics and alkanes in a mass ratio of 1:2; the heavy aromatics is D100#; and the alkane is n-butane.

[0063] The curing agent is a ketimine curing agent.

[0064] The heavy aromatics D100# and D120# used in the above Examples 1-3 were produced from Changzhou Heshili Chemical Co., Ltd.

[0065] Comparative Example 1

[0066] Comparative Example 1 is the same as Example 1, except that the hydroxylated epoxy soybean oil modified polyurethane prepolymer is replaced by waterborne polyurethane.

[0067] Comparative Example 2

[0068] Comparative Example 2 is the same as Example 1, except that no sodium silicate is added to the raw materials.

[0069] Performance Testing

[0070] The antifreeze performance, compression strength and bonding strength of the products in Examples 1-3 and Comparative Examples 1-2 were tested, and the results are shown in Table 1.

[0071] Table 1

[0072]

[0073] It can be seen from the above table that the repair material for tunnel leakage in plateau and cold regions provided by the present invention has good antifreeze performance, compression strength and bonding strength.

[0074] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0075] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A repair material for tunnel leakage in high-altitude and cold areas, characterized in that: The invention comprises the following components in parts by weight: 80-120 parts of superfine cement, 30-50 parts of compatibilizer, 20-30 parts of hydroxylated epoxy soybean oil modified polyurethane prepolymer, 10-20 parts of waterborne epoxy resin, 10-20 parts of metakaolin, 10-15 parts of sodium silicate and 10-15 parts of curing agent.

2. The repair material for tunnel leakage in plateau and cold regions according to claim 1 is characterized in that: The NCO content of the hydroxylated epoxy soybean oil modified polyurethane prepolymer is 7-9%.

3. The repair material for tunnel leakage in plateau and cold regions according to claim 2 is characterized in that: The hydroxylated epoxy soybean oil modified polyurethane prepolymer is prepared by the following method: (1) Add polyethylene glycol to a reaction kettle, perform vacuum dehydration at 112-115° C. for 1-2 hours, add isophorone diisocyanate when the temperature drops to 45-55° C., then slowly raise the temperature to 70-80° C. and react for 2-3 hours; (2) The temperature of the material in (1) is lowered by 40-45° C., a catalyst is added, the temperature is slowly raised to 70-80° C., hydroxylated epoxy soybean oil is added dropwise, and the reaction is stopped when the NCO content is 7%-9%, thereby obtaining a hydroxylated epoxy soybean oil-modified polyurethane prepolymer.

4. The repair material for tunnel leakage in plateau and cold regions according to claim 3 is characterized in that: The molar ratio of the polyethylene glycol to isophorone diisocyanate is 1:

2.

5. The repair material for tunnel water leakage in plateau and cold regions according to claim 4 is characterized in that: The catalyst is dibutyltin dilaurate.

6. The repair material for tunnel water leakage in plateau and cold regions according to claim 5 is characterized in that: The amount of the catalyst is 0.02-0.03% of the sum of the mass of polyethylene glycol and isophorone diisocyanate.

7. The repair material for tunnel leakage in plateau and cold regions according to claim 2 is characterized in that: The model of the water-based epoxy resin is CYDW-100.

8. The repair material for tunnel water leakage in plateau and cold regions according to claim 2 is characterized in that: The compatibilizer is a mixture of heavy aromatics and alkanes in a mass ratio of 1:(1-2); the heavy aromatics include D100# or D120#; and the alkanes include n-butane or hexane.

9. The repair material for tunnel leakage in plateau and cold regions according to claim 2, characterized in that: The curing agent is a ketimine curing agent.

10. A method for preparing a repair material for tunnel leakage in plateau and cold regions according to any one of claims 2 to 9, characterized in that: The following steps are involved: a. Add ultrafine cement and metakaolin into a mixer, stir and mix, then add compatibilizer and water, and stir for 3-5 minutes; b. Add hydroxylated epoxy soybean oil modified polyurethane prepolymer and water-based epoxy resin, continue stirring for 2-3 minutes, add sodium silicate and curing agent, stir evenly, and the repair material can be obtained.

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