Water-rich tunnel grouting slurry and grouting process

Abstract

The application relates to the field of tunnel grouting materials and grouting processes, and specifically discloses a water-rich tunnel grouting slurry and a grouting process, wherein the slurry is made of cement composite slurry and water glass, and the volume ratio of the cement composite slurry to the water glass is 4: (1-3); the cement composite slurry raw material comprises cement 40 parts, fillers 55-70 parts, water 48-82 parts, water reducing agent 0.4-1.2 parts, anti-erosion agent 0.5-1.5 parts, anti-cracking agent 1.3-2.7 parts; the anti-erosion agent comprises the following raw materials in parts by weight: basalt short fibers 10 parts, sugarcane residue powder 1-3 parts, dicyclopentadiene 1.5-4.5 parts, insoluble polymer 3-8 parts, polymerization inhibitor 0.01 part; and the water glass has a Baume degree of 30Bé-39Bé. The slurry is used for grouting by adopting an advancing deep-hole grouting process. The application has the effect of improving the water erosion resistance of surrounding rock.

Description

Technical Field

[0001] This application relates to the field of tunnel grouting materials and grouting processes, and in particular to a grouting slurry and grouting process for water-rich tunnels. Background Technology

[0002] my country has a vast territory, with mountainous areas accounting for approximately 70% of its land area. Its geographical and geological conditions are extremely complex, making it the country with the most widespread karst distribution in the world. Based on the distribution of soluble strata, the area covered reaches 3.443 × 10⁶ km². 2 Its total area accounts for approximately one-third of my country's land area; calculated by the area of ​​exposed carbonate rocks, its distribution area is 0.907 × 10⁶ km². 2 The total area is close to 1 / 10 of my country's land area. A considerable proportion of the tunnels that have been built or are under construction in the western region are located in karst areas. Among the 17 medium and long karst railway tunnels that have been built in the southwest and central south regions, nearly 50% have experienced karst disasters. Water inrush and other disasters have become one of the most serious and common geological hazards in the construction of tunnels in karst areas of my country.

[0003] Common methods for resisting karst disasters such as tunnel water inrush include advanced geological forecasting, grouting reinforcement, tunnel drainage, and setting up parallel pilot tunnels. Among these, grouting pre-reinforcement improves the self-stabilizing performance of the surrounding rock, reduces the range of the relaxation zone caused by excavation deformation, reduces the adverse effects of cracked and sliding layers near the ground surface on tunnel excavation, and prevents collapse and roof fall.

[0004] Commonly used grouting materials in grouting reinforcement include single-component inert grouting materials, single-component rigid grouting materials, and cement-water glass dual-component grouting materials. Among them, cement-water glass dual-component grouting materials are active grouts with the characteristics of fast setting speed, high early strength and high long-term strength, and are suitable for grouting reinforcement behind tunnel walls.

[0005] In water-rich areas, grouting reinforcement is carried out behind the shield tunnel walls. After the cement-water glass dual-liquid grout solidifies, it forms the surrounding rock. The surrounding rock is subjected to water erosion over a long period of time. The hydration products on the surface of the surrounding rock continuously migrate and dissolve outward, forming a porous structure on the outer surface of the surrounding rock. Sodium, silicate ions and hydration products in the internal structure of the surrounding rock migrate outward from the porous structure, resulting in a decrease in the mechanical properties of the surrounding rock and a weakening of its barrier effect against liquid water. Summary of the Invention

[0006] In order to improve the water erosion resistance of the surrounding rock, this application provides a grouting slurry and grouting process for water-rich tunnels.

[0007] Firstly, the technical solution for a water-rich tunnel grouting slurry provided in this application is as follows:

[0008] A water-rich tunnel grout is made of cement composite grout and water glass, wherein the volume ratio of cement composite grout to water glass is (4-6):5;

[0009] The cement composite slurry comprises the following raw materials in parts by weight: 40 parts cement; 55-70 parts filler; 48-82 parts water; 0.4-1.2 parts water-reducing agent; 0.5-1.5 parts corrosion inhibitor; and 1.3-2.7 parts crack-resistant agent.

[0010] The corrosion inhibitor comprises the following raw materials in parts by weight: 10 parts basalt short fibers; 1-3 parts bagasse powder; 1.5-4.5 parts dicyclopentadiene; 3-8 parts insoluble polymer; and 0.01 parts polymerization inhibitor.

[0011] The water glass has a Baume degree of 30-39 Bé.

[0012] By adopting the above technical solution, the basalt short fibers in the anti-corrosion agent are modified by sugarcane bagasse powder and dicyclopentadiene to form modified fibers with high friction coefficient, water resistance, and fixed ions. In the cement-water glass two-liquid system, the modified fibers and insoluble polymers form a three-dimensional network structure, which improves the anti-segregation performance of the cement-water glass two-liquid system. The presence of the anti-polymerization agent makes it difficult for the insoluble polymer to undergo polymerization reaction, effectively controlling the viscosity of the cement-water glass two-liquid system and reducing the probability of problems such as pipe blockage and small permeation range. After the grouting slurry in the water-rich tunnel forms the surrounding rock, the insoluble polymer fills the pores between the basalt short fibers and the filler, as well as the pores between the cement and the filler, improving the self-sealing of the surrounding rock and preventing water molecules from invading the surrounding rock. Sugarcane bagasse adsorbs metal ions and silicate ions through physical and chemical action, preventing the migration of metal ions and silicate ions to the outside of the surrounding rock, thereby maintaining the mechanical properties of the surrounding rock. Simultaneously, dicyclopentadiene and the insoluble polymer immobilize the bagasse, reducing the probability of bagasse leaching and improving the stability of the surrounding rock. When liquid water erodes into the surrounding rock, the combined effect of the insoluble polymer and dicyclopentadiene enhances the rock's ability to resist liquid water. In summary, the combined action of cement, filler, solvent inhibitor, and water glass improves the water erosion resistance of the surrounding rock.

[0013] Optionally, the preparation of the anti-corrosion agent includes the following steps: mixing dicyclopentadiene and bagasse powder evenly and heating to 33-35°C, then adding basalt short fibers, stirring evenly, cooling to room temperature, and allowing to stand, shake, and comb to obtain modified fibers; mixing insoluble polymer and polymerization inhibitor evenly, adding modified fibers, heating to 31-33°C, stirring at a constant temperature for 10-20 minutes, cooling to room temperature, and allowing to stand, shake, and disperse to obtain the anti-corrosion agent.

[0014] By employing the above technical solution, dicyclopentadiene melts at a temperature of 33-35℃, and bagasse powder adsorbs dicyclopentadiene molecules. The dicyclopentadiene then evenly disperses the bagasse powder. After adding basalt short fibers, under the influence of the carbon-carbon double bonds in the dicyclopentadiene and the surface groups of the basalt short fibers, the dicyclopentadiene and bagasse powder are evenly dispersed on the surface of the basalt short fibers, forming modified fibers. The modified fibers are then mixed with insoluble polymers and polymerization inhibitors. At 31-33℃, some of the insoluble polymers adhere to the surface of the modified fibers, while others adhere to each other, forming a network structure. However, due to the presence of the polymerization inhibitor, the anti-corrosion agent does not easily self-polymerize, effectively controlling the viscosity. At this point, the dicyclopentadiene repairs the surface cracks of the basalt short fibers, improving their strength. The anti-corrosion agent prepared through the above steps improves the stability of the surrounding rock, making it less susceptible to water erosion by liquid water, thus enhancing the water erosion resistance of the surrounding rock.

[0015] Optionally, the insoluble polymer is selected from low molecular weight insoluble polymers.

[0016] By adopting the above technical solution, the low molecular weight insoluble polymer has low viscosity, which makes it easier to control the viscosity of the cement-water glass dual liquid material and reduces the probability of pipe blockage during grouting.

[0017] Optionally, the insoluble polymer is selected from one of low molecular weight polycaprolactone, low molecular weight polyurethane elastomer, and low molecular weight polytetrafluoroethylene.

[0018] By adopting the above technical solution, low molecular weight polycaprolactone, low molecular weight polyurethane elastomer, and low molecular weight polytetrafluoroethylene provide a certain viscosity for the anti-corrosion agent, facilitating the formation of a three-dimensional network structure; simultaneously, these substances are water-resistant and water-repellent, improving the water erosion resistance of the surrounding rock. Preferably, the insoluble polymer is selected from low molecular weight polycaprolactone with a molecular weight of 2000 g / mol-5000 g / mol, resulting in an anti-corrosion agent with stable performance and strong water erosion resistance.

[0019] Optionally, the polymerization inhibitor is selected from hydroquinone.

[0020] By employing the above technical solution, hydroquinone reacts with the double bonds in the polycaprolactone molecular chain to generate a stable, insoluble product, thereby inhibiting the polymerization of low-molecular-weight polycaprolactone and effectively controlling the viscosity of the anti-corrosion agent. Hydroquinone also reacts with magnesium and calcium ions in the cement-water glass two-liquid system to form insoluble substances, reducing the probability of ion migration from the surrounding rock into the water and improving the water erosion resistance of the surrounding rock.

[0021] Optionally, the cement is ultrafine silicate cement.

[0022] By adopting the above technical solution, ordinary silicate cement particles are too large to be injected into soil with pores or cracks smaller than 0.2 mm. Using ultrafine silicate cement makes it easier for the grout to penetrate into the soil, thus improving the stability of the surrounding rock.

[0023] Optionally, the crack-resistant agent comprises hydroxypropyl cellulose and ethylene-vinyl acetate copolymer, wherein the weight ratio of hydroxypropyl cellulose to ethylene-vinyl acetate copolymer is (16-17):10.

[0024] By adopting the above technical solutions, hydroxypropyl methylcellulose can improve the dispersibility of particles in the slurry system and enhance the pumping stability of the slurry, making it less prone to segregation and stratification. The combination of hydroxypropyl methylcellulose and ethylene-vinyl acetate copolymer enhances the dynamic water erosion resistance of the slurry and improves the retention rate of aggregates under water-rich conditions. In water-rich areas, during the slurry solidification process, the cement hydration generates heat, leading to volume expansion. As the temperature decreases in the later stages, shrinkage cracks are easily generated. Adding ethylene-vinyl acetate copolymer to the slurry provides resilience and reduces the probability of shrinkage cracks.

[0025] Optionally, the filler includes slag, fly ash, and sodium-based bentonite, wherein the weight ratio of the slag, fly ash, and sodium-based bentonite is (8-60):(57-210):5.

[0026] By adopting the above technical solution, the combination of slag, fly ash and sodium-based bentonite improves the self-sealing property of cement-water glass double-liquid surrounding rock, thereby improving the water erosion resistance of the surrounding rock.

[0027] Secondly, the grouting process for water-rich tunnels provided in this application adopts the following technical solution:

[0028] A grouting process for water-rich tunnels employs a forward-moving deep-hole grouting technique and uses the aforementioned water-rich tunnel grouting slurry for grouting.

[0029] By adopting the above technical solutions and using the forward deep-hole grouting process, the strength and stability of the strata are improved, the water-blocking and water-retaining capacity of the tunnel surrounding rock is enhanced, construction in water-rich areas is facilitated, and the probability of karst disasters such as tunnel water inrush is reduced.

[0030] Optionally, the initial grouting pressure is 0.9-1MPa, the final grouting pressure is 0.2-0.3MPa, the grouting speed is 20-40L / min, and the forward segmented grouting length is 2-3m.

[0031] By adopting the above technical solution and adjusting the grouting process, the cement-water glass dual-liquid grout penetrates into the soil in the water-rich area and solidifies rapidly, reducing the probability of soil collapse caused by the grout impacting the soil in the water-rich area and improving the safety of the construction process.

[0032] In summary, this application includes at least one of the following beneficial technical effects:

[0033] 1. During the curing process of cement-water glass two-component slurry, the anti-corrosion agent forms a three-dimensional network structure. The low molecular weight polycaprolactone in the anti-corrosion agent fills the gaps between basalt short fibers and fillers, and between basalt short fibers and cement particles, improving the self-compactness of the surrounding rock, preventing water molecules from penetrating the surrounding rock, and improving the water erosion resistance of the surrounding rock. The surface of the above-mentioned three-dimensional network structure is composed of dicyclopentadiene that decomposes water molecules and bagasse powder that fixes ions, preventing water molecules from eroding into the surrounding rock. At the same time, it adsorbs metal ions and silicate ions through physical and chemical actions, preventing metal ions and silicate ions from migrating to the outside of the surrounding rock, thereby maintaining the mechanical properties of the surrounding rock. The surrounding rock is not prone to cracking under pressure, further improving the water erosion resistance of the surrounding rock.

[0034] 2. Dicyclopentadiene acts as a binder, binding and fixing basalt short fibers, bagasse powder, and polycaprolactone, facilitating the action of the anti-corrosion agent. The carbon-carbon double bonds in dicyclopentadiene react with hydrogen and oxygen atoms in water molecules to generate substances insoluble in water. Simultaneously, it reacts with oxygen in the air to generate highly reactive free radicals. These free radicals further react with water molecules, promoting the decomposition and evaporation of water molecules, thereby consuming the invading water molecules, delaying the erosion of the solidified material / surrounding rock by water molecules, and improving the water erosion resistance of the surrounding rock.

[0035] 3. Hydroquinone reacts with the double bonds in the polycaprolactone molecular chain to form a stable, insoluble product, thereby inhibiting the polymerization of low-molecular-weight polycaprolactone and effectively controlling the viscosity of the anti-corrosion agent. Hydroquinone reacts with magnesium and calcium ions in the cement-water glass two-liquid system to form insoluble substances, reducing the probability of ions migrating from the surrounding rock into the water and improving the water erosion resistance of the surrounding rock.

[0036] 4. Hydroxypropyl methylcellulose can improve the dispersibility of particles in the slurry system and enhance the pumping stability of the slurry, making it less prone to segregation and stratification. The combination of hydroxypropyl methylcellulose and ethylene-vinyl acetate copolymer enhances the dynamic water erosion resistance of the slurry and improves the retention rate of aggregates under water-rich conditions. In water-rich areas, during the slurry solidification process, the cement hydration generates heat, leading to volume expansion. As the temperature decreases in the later stages, shrinkage cracks are easily generated. Adding ethylene-vinyl acetate copolymer to the slurry provides resilience and reduces the probability of shrinkage cracks. Detailed Implementation

[0037] The present application will be further described in detail below with reference to embodiments and comparative examples.

[0038] Unless otherwise specified, the following examples shall be conducted under conventional conditions or conditions recommended by the manufacturer. Unless otherwise specified, all raw materials used in the following examples shall be commercially available.

[0039] The ultrafine silicate cement is grade 42.5 cement with a specific surface area of ​​850 m². 2 / kg, initial setting time 150min, final setting time 210min, D 50 The flow rate is 4.2 μm, the initial flow rate is 255, and the flow rate at 60 min is 180.

[0040] The slag is selected from blast furnace slag, with a specific surface area of ​​448 m². 2 / kg.

[0041] The fly ash is classified as Class II fly ash, with a water requirement of 98%, a loss on ignition of 5.78%, and a specific surface area of ​​516 m². 2 / kg.

[0042] Sodium-based bentonite showed a wet sieve residue of 2.3%, a filtration loss of 8 mL over 30 minutes, a yield value / plastic viscosity ratio of 2.5, and a viscosity of 38 mPa·s at 600 r / min.

[0043] The water-reducing agent is selected from naphthalene-based water-reducing agents.

[0044] The basalt short fibers have an average diameter of 13 μm, a length of 3 mm, a tensile strength of 1800 MPa, an elongation at break of 2.5%, and an elastic modulus of 81.7 GPa.

[0045] Sugarcane bagasse powder is a fine powder made by drying sugarcane bagasse and grinding it, with a particle size of 800 mesh.

[0046] Dicyclopentadiene, a byproduct of petroleum cracking to produce ethylene and coal coking, has a melting point of 33°C and a density of 0.979 g / cm³. 3 .

[0047] Low molecular weight polycaprolactone, with a molecular weight of 3000 g / mol.

[0048] Example

[0049] Example 1

[0050] S1. Mix 1.5 kg of dicyclopentadiene and 1 kg of bagasse powder evenly, heat to 34°C, stir at a constant temperature, then add to 10 kg of basalt short fibers, stir evenly at 34°C, cool to room temperature, let stand, shake, and comb to obtain modified fibers; Mix 3 kg of low molecular weight polycaprolactone and 0.01 kg of hydroquinone evenly, add to modified fibers, heat to 32°C, stir at a constant temperature for 15 min, cool to room temperature, let stand, shake, and disperse to obtain an anti-corrosion agent;

[0051] S2. Mix 40 kg of ultrafine silicate cement and 0.5 kg of the anti-corrosion agent prepared in S1 evenly. Then add 12 kg of slag, 42 kg of fly ash, 1 kg of sodium bentonite, 48 kg of water, 0.4 kg of naphthalene-based water-reducing agent, 0.8 kg of hydroxypropyl methylcellulose and 0.5 kg of ethylene-vinyl acetate copolymer and mechanically mix and stir. Use intermittent stirring, stirring for 2 min, stopping for 15 s, stirring for 20 min, stirring speed 750±5 r / min to obtain cement composite slurry.

[0052] S3. Add 30 Bé water glass at a volume ratio of 4:5, stir for 20 min at a stirring speed of 750±5 r / min to obtain water-rich tunnel grouting slurry.

[0053] Example 2

[0054] S1. Mix 3 kg of dicyclopentadiene and 2 kg of bagasse powder evenly, heat to 34°C, stir at a constant temperature, then add to 10 kg of basalt short fibers, stir evenly at 34°C, cool to room temperature, let stand, shake, and comb to obtain modified fibers; Mix 5 kg of low molecular weight polycaprolactone and 0.01 kg of hydroquinone evenly, add to modified fibers, heat to 32°C, stir at a constant temperature for 15 min, cool to room temperature, let stand, shake, and disperse to obtain an anti-corrosion agent;

[0055] S2. Mix 40 kg of ultrafine silicate cement and 1 kg of the anti-corrosion agent prepared in S1 evenly. Then add 10 kg of slag, 50 kg of fly ash, 3 kg of sodium bentonite, 70 kg of water, 0.8 kg of naphthalene-based water-reducing agent, 1.2 kg of hydroxypropyl methylcellulose and 0.8 kg of ethylene-vinyl acetate copolymer and mechanically mix and stir. Use intermittent stirring, stirring for 2 min, stopping for 15 s, stirring for 20 min, stirring speed 750±5 r / min to obtain cement composite slurry.

[0056] S3. Add 35 Bé water glass at a volume ratio of 1:1, stir for 20 minutes at a stirring speed of 750±5 r / min to obtain water-rich tunnel grouting slurry.

[0057] Example 3

[0058] S1. Mix 4.5 kg of dicyclopentadiene with 3 kg of bagasse powder evenly and heat to 34°C. Stir at a constant temperature and then add to 10 kg of basalt short fibers. Stir evenly at 34°C and then cool to room temperature. Let stand, shake, and comb to obtain modified fibers. Mix 8 kg of low molecular weight polycaprolactone and 0.01 kg of hydroquinone evenly and add to the modified fibers. Heat to 32°C and stir at a constant temperature for 15 min. Cool to room temperature and let stand, shake, and disperse to obtain an anti-corrosion agent.

[0059] S2. Mix 40 kg of ultrafine silicate cement and 1.5 kg of the anti-corrosion agent prepared in S1 evenly. Then add 8 kg of slag, 57 kg of fly ash, 5 kg of sodium bentonite, 82 kg of water, 1.2 kg of naphthalene-based water-reducing agent, 1.7 kg of hydroxypropyl methylcellulose and 1 kg of ethylene-vinyl acetate copolymer and mechanically mix and stir. Use intermittent stirring, stirring for 2 min, stopping for 15 s, stirring for 20 min, stirring speed 750±5 r / min to obtain cement composite slurry.

[0060] S3. Add 39 Bé water glass at a volume ratio of 6:5, stir for 20 minutes at a stirring speed of 750±5 r / min to obtain water-rich tunnel grouting slurry.

[0061] Table 1. Raw material list (kg) for Examples 1-3

[0062]

[0063]

[0064] Example 4

[0065] The difference from Example 2 is that the amount of sugarcane bagasse powder added to the anti-corrosion agent is 1 kg.

[0066] Example 5

[0067] The difference from Example 2 is that the amount of bagasse powder added to the anti-corrosion agent is 3 kg.

[0068] Example 6

[0069] The difference from Example 2 is that the amount of dicyclopentadiene added to the anti-corrosion agent is 1.5 kg.

[0070] Example 7

[0071] The difference from Example 2 is that the amount of dicyclopentadiene added to the anti-corrosion agent is 1.5 kg.

[0072] Example 8

[0073] The difference from Example 2 is that the amount of polycaprolactone added to the anti-corrosion agent is 3 kg.

[0074] Example 9

[0075] The difference from Example 2 is that the amount of polycaprolactone added in the anti-corrosion agent is 8 kg.

[0076] Table 2. Raw material list (kg) of the anti-corrosion agent in Examples 2 and 4-5.

[0077] Basalt short fibers sugarcane bagasse powder Dicyclopentadiene Polycaprolactone hydroquinone Example 2 10 2 3 5 0.01 Example 4 10 1 3 5 0.01 Example 5 10 3 3 5 0.01 Example 6 10 2 1.5 5 0.01 Example 7 10 2 4.5 5 0.01 Example 8 10 2 3 3 0.01 Example 9 10 2 3 8 0.01

[0078] Example 10

[0079] The difference from Example 2 is that the amount of hydroxypropyl methylcellulose added is 1.5 kg, and the amount of ethylene-vinyl acetate copolymer added is 0.5 kg.

[0080] Example 11

[0081] The difference from Example 2 is that the amount of hydroxypropyl methylcellulose added is 1.9 kg, and the amount of ethylene-vinyl acetate copolymer added is 0.1 kg.

[0082] Example 12

[0083] The difference from Example 2 is that the added water glass has a Baume degree of 30 Bé.

[0084] Example 13

[0085] The difference from Example 2 is that the added water glass has a Baume degree of 39 Bé.

[0086] Example 14

[0087] The difference from Example 2 is that the volume ratio of cement composite slurry to water glass is 4:5.

[0088] Example 15

[0089] The difference from Example 2 is that the volume ratio of cement composite slurry to water glass is 6:5.

[0090] Example 16

[0091] The deep hole grouting process is adopted, and the water-rich tunnel grouting slurry prepared in Example 2 is used for grouting. The specific steps are as follows: (1) The tunnel face is sealed with 30cm of conventional shotcrete.

[0092] (2) Mark the position of the borehole on the working face. The deviation of the borehole position shall not be greater than 20mm and the deviation of the drilling angle shall not be greater than 1°.

[0093] (3) Drill holes using a drilling rig, and then grout into the holes. The grouting parameters are: initial grouting pressure of 0.9-1 MPa, pressure during grouting of 0.15-0.75 MPa, final grouting pressure of 0.2-0.3 MPa, grouting speed of 20-40 L / min, and forward segmented grouting length of 2-3 m. In this embodiment, the grouting parameters are: initial grouting pressure of 1 MPa, pressure during grouting of 0.5 MPa ± 0.05 MPa, final grouting pressure of 0.25 MPa, grouting speed of 30 L / min, and forward segmented grouting length of 2.5 m;

[0094] (4) After the deep hole grouting is completed, before the tunnel is officially excavated, core sampling is required to determine the compressive strength. If the soil strength is less than 1.5 MPa, grouting is added until the soil strength meets the requirements.

[0095] Comparative Example

[0096] Comparative Example 1

[0097] S1. Mechanically mix 40kg of ultrafine silicate cement, 10kg of slag, 50kg of fly ash, 3kg of sodium bentonite, 70kg of water, and 0.8kg of naphthalene-based water-reducing agent. Use intermittent mixing, mixing for 2 minutes, stopping for 15 seconds, for a total mixing time of 20 minutes, and a mixing speed of 750±5r / min to obtain cement composite slurry.

[0098] S2. Add 35 Bé water glass at a volume ratio of 1:1, stir for 20 minutes at a stirring speed of 750±5 r / min to obtain water-rich tunnel grouting slurry.

[0099] Comparative Example 2

[0100] S1. Mechanically mix 40kg of ultrafine silicate cement, 10kg of slag, 50kg of fly ash, 3kg of sodium bentonite, 70kg of water, 0.8kg of naphthalene-based water-reducing agent, 1.2kg of hydroxypropyl methylcellulose and 0.8kg of ethylene-vinyl acetate copolymer. Use intermittent mixing, mixing for 2 minutes, stopping for 15 seconds, for a total mixing time of 20 minutes, and a mixing speed of 750±5r / min to obtain cement composite slurry.

[0101] S2. Add 35 Bé water glass at a volume ratio of 1:1, stir for 20 minutes at a stirring speed of 750±5 r / min to obtain water-rich tunnel grouting slurry.

[0102] Comparative Example 3

[0103] The difference from Example 2 is that no anti-corrosion agent was prepared and used, and 1 kg of basalt short fibers were added.

[0104] Comparative Example 4

[0105] The difference from Example 2 is that: S1, 10 kg of basalt short fibers and 2 kg of sugarcane bagasse powder are mixed evenly as an anti-corrosion agent.

[0106] Comparative Example 5

[0107] The difference from Example 2 is as follows: S1, 3 kg of dicyclopentadiene is heated to 34°C and stirred at a constant temperature. Then it is added to 10 kg of basalt short fibers, stirred evenly at a constant temperature of 34°C, and then cooled to room temperature. The solution is then allowed to stand, shaken, and combed to resist corrosion.

[0108] Comparative Example 6

[0109] The difference from Example 2 is as follows: S1, 10 kg of basalt short fibers and 3 kg of low molecular weight polycaprolactone are mixed evenly, heated to 34°C, stirred at a constant temperature for 15 min, cooled to room temperature, and then allowed to stand, shake, and dispersed to obtain an anti-corrosion agent.

[0110] Comparative Example 7

[0111] The difference from Example 2 is that hydroquinone was not added to the anti-corrosion agent.

[0112] Comparative Example 8

[0113] The difference from Example 2 is that hydroxypropyl methylcellulose and ethylene-vinyl acetate copolymer were not added.

[0114] Comparative Example 9

[0115] The difference from Example 2 is that hydroxypropyl methylcellulose was not added.

[0116] Comparative Example 10

[0117] The difference from Example 2 is that no ethylene-vinyl acetate copolymer was added.

[0118] Table 3. Raw material list (kg) of cement composite slurry in Example 2 and Comparative Example.

[0119]

[0120]

[0121] Performance testing

[0122] Test methods

[0123] 1. The initial setting time (s) and final setting time (s) of the grout were determined using the method in GB / T1346-2011 Cement Standard Consistency Water Requirement, Setting Time and Soundness Test Method. The experimental temperature was 20℃±2℃ and the relative humidity was 60%±2%. The temperature of the moisture curing chamber was 20℃±2℃ and the relative humidity was 95%±2%. The experimental results are shown in Table 4.

[0124] 2. The grout was placed in a mold and cured for 7 days at 20℃±2℃ and 65%±2% relative humidity. The grout was then cut into prism specimens of 40mm×40mm×160mm. The specimens were placed in a water tank and water was added to cover them. The solid content of the water was required to be less than 0.01g / L. After soaking for 28 days, the specimens were removed, and the remaining liquid was allowed to stand, filtered, and distilled to obtain the solidified product. The dissolved solids content (g / L) after 28 days was obtained. The calculation formula is: dissolved solids content (g / L) after 28 days = (weight of solidified product (g) / volume of liquid (L)). The experimental results are shown in Table 4.

[0125] 3. The 28-day compressive strength (MPa) of the grout was determined using the method in GB / T17671-1999 Cement Mortar Strength Test Method (ISO Method). The experimental results are shown in Table 4.

[0126] Table 4. Test results data for each embodiment and comparative example.

[0127]

[0128]

[0129] Based on Examples 1, 2, and 3 and Table 4, a water-erosion-resistant grouting slurry for water-rich tunnels was prepared by adjusting the proportions of each material in the cement composite slurry, the Baumé degree of the water glass, and the volume ratio of the cement composite slurry to the water glass.

[0130] The differences between Examples 2, 4, and 5 are as follows: In Example 2, the amount of bagasse powder added to the anti-corrosion agent was 2 kg; in Example 4, the amount of bagasse powder added was 1 kg; and in Example 5, the amount of bagasse powder added was 3 kg. As can be seen from Table 4, with the increase of bagasse powder added to the anti-corrosion agent, the initial setting time and final setting time of the slurry both shortened and then lengthened, the dissolved solids content at 28 days first decreased and then increased, and the compressive strength of the 28-day aggregate decreased.

[0131] The differences between Examples 2, 6, and 7 are as follows: In Example 2, the amount of dicyclopentadiene added to the anti-corrosion agent was 3 kg; in Example 4, the amount of dicyclopentadiene added was 1.5 kg; and in Example 5, the amount of dicyclopentadiene added was 4.5 kg. As can be seen from Table 4, with the increase of dicyclopentadiene added to the anti-corrosion agent, the initial setting time and final setting time of the slurry both shortened and then lengthened, the dissolved solids content at 28 days first decreased and then increased, and the compressive strength of the 28-day aggregate increased.

[0132] The differences between Examples 2, 8, and 9 are as follows: In Example 2, the amount of polycaprolactone added to the anti-corrosion agent was 5 kg; in Example 4, the amount of polycaprolactone added was 3 kg; and in Example 5, the amount of polycaprolactone added was 8 kg. As can be seen from Table 4, with the increase of polycaprolactone added to the anti-corrosion agent, the initial setting time and final setting time of the slurry were prolonged, the dissolved solids content at 28 days first decreased and then increased, and the compressive strength of the 28-day aggregate increased.

[0133] A mixture of hydroxypropyl methylcellulose and ethylene-vinyl acetate copolymer was used as an anti-cracking agent. In Examples 2, 10, and 11, the amount of anti-cracking agent added was the same, 2 kg. However, the differences were as follows: In Example 2, the amount of hydroxypropyl methylcellulose added was 1.2 kg, and the amount of ethylene-vinyl acetate copolymer added was 0.8 kg, with a weight ratio of 3:2; in Example 10, the amount of hydroxypropyl methylcellulose added was 1.5 kg, and the amount of ethylene-vinyl acetate copolymer added was 0.5 kg. The weight ratio of hydroxypropyl methylcellulose to ethylene-vinyl acetate copolymer was 3:1; in Example 11, the amount of hydroxypropyl methylcellulose added was 1.9 kg, the amount of ethylene-vinyl acetate copolymer added was 0.1 kg, and the weight ratio of hydroxypropyl methylcellulose to ethylene-vinyl acetate copolymer was 19:1; as shown in Table 4, with the increase of the weight ratio of hydroxypropyl methylcellulose to ethylene-vinyl acetate copolymer, the initial setting time and final setting time of the slurry first shortened and then lengthened, the dissolved solids content at 28 days did not change much, and the compressive strength of the 28-day stone body first decreased and then increased.

[0134] The differences between Examples 2, 12, and 13 are as follows: Example 2 uses water glass with a Baume degree of 35 Bé; Example 12 uses water glass with a Baume degree of 30 Bé; and Example 13 uses water glass with a Baume degree of 39 Bé. As can be seen from Table 4, with the increase of the Baume degree of the water glass, the initial setting time and final setting time of the slurry shorten, the dissolved solids content at 28 days first decreases and then increases, and the compressive strength of the 28-day aggregate first increases and then decreases.

[0135] The differences between Examples 2, 14, and 15 are as follows: In Example 2, the volume ratio of cement composite additive to water glass is 1:1; in Example 14, the volume ratio is 4:5; and in Example 15, the volume ratio is 6:5. As shown in Table 4, with the increase of the volume ratio of cement composite additive to water glass, the initial setting time and final setting time of the slurry shorten, the dissolved solids content at 28 days decreases, and the compressive strength of the 28-day aggregate first increases and then decreases.

[0136] In Comparative Example 1, cement composite slurry was prepared using only ultrafine silicate cement, slag, fly ash, sodium bentonite, water, and naphthalene-based water-reducing agent, without the addition of anti-corrosion agent and anti-cracking agent. The slurry prepared by this cement composite slurry with water glass had a fast initial setting and a fast final setting, but the content of dissolved solids was high at 28 days and the compressive strength of the 28-day aggregate was low.

[0137] Compared to Comparative Example 1, Comparative Example 2 showed an increase in the initial and final setting times of the slurry due to the addition of crack-resistant agent, while also improving compressive strength and reducing the dissolved solids content at 28 days. However, compared to Example 2, the slurry prepared in Comparative Example 2 showed a significant increase in dissolved solids content at 28 days and lower compressive strength of the 28-day aggregate.

[0138] Compared to Comparative Example 2, Comparative Example 3 showed a slight increase in the 28-day compressive strength of the slurry with the addition of basalt short fibers, and a slight decrease in the 28-day dissolved solids content. However, compared to Example 2, the slurry prepared in Comparative Example 3 showed a significant increase in the 28-day dissolved solids content and a lower 28-day compressive strength of the slurry.

[0139] Compared to Comparative Example 2, Comparative Example 4, which added basalt short fibers and bagasse powder to prepare the anti-corrosion agent, showed shorter initial and final setting times, slightly increased 28-day compressive strength of the slurry, and slightly decreased 28-day dissolved solids content. Compared to Comparative Example 3, Comparative Example 4, which added bagasse powder, actually showed an increase in 28-day dissolved solids content. This was mainly because the lack of a binding effect from dicyclopentadiene led to the bagasse powder increasing the porosity within the surrounding rock.

[0140] Compared to Comparative Example 2, the anti-corrosion agent prepared by adding basalt short fibers and dicyclopentadiene to Comparative Example 5 showed increased 28-day compressive strength of the slurry and decreased 28-day dissolved solids content. However, compared to Example 2, the slurry prepared in Comparative Example 2 showed a significant increase in 28-day dissolved solids content and low 28-day compressive strength of the slurry.

[0141] Compared to Comparative Example 2, the anti-corrosion agent prepared by adding basalt short fibers and polycaprolactone in Comparative Example 6 showed increased 28-day compressive strength of the slurry and decreased 28-day dissolved solids content. However, compared to Example 2, the slurry prepared in Comparative Example 2 showed a significant increase in 28-day dissolved solids content and low 28-day compressive strength of the slurry.

[0142] Compared to Example 2, Hydroquinone was not added to the anti-corrosion agent used in Comparative Example 7. As can be seen from Table 4, the addition of Hydroquinone increased the 28-day compressive strength of the slurry and reduced the 28-day dissolved solids content of the slurry.

[0143] As can be seen from Examples 2 and Comparative Examples 3-7, the combination of basalt short fiber, bagasse powder, dicyclopentadiene, polycaprolactone, and hydroquinone effectively reduced the 28-day dissolved solids content and improved the 28-day compressive strength of the stone body. The effect of using any of the raw materials alone when they are missing is far lower than that of this combination.

[0144] Compared to Comparative Example 1, Comparative Example 8 added an anti-corrosion agent but no anti-cracking agent, resulting in shorter initial and final setting times, increased 28-day compressive strength, and reduced 28-day dissolved solids content. However, compared to Example 2, the slurry prepared in Comparative Example 2 showed a significant increase in 28-day dissolved solids content and lower 28-day stone compressive strength.

[0145] Compared to Comparative Example 8, Comparative Example 9 added ethylene-vinyl acetate copolymer but did not add hydroxypropyl methylcellulose, and Comparative Example 10 added hydroxypropyl methylcellulose but did not add ethylene-vinyl acetate copolymer. As can be seen from Example 2 and Table 4, compared to using hydroxypropyl methylcellulose and ethylene-vinyl acetate copolymer alone, the combination of the two more effectively reduced the dissolved solids content at 28 days and improved the compressive strength of the 28-day stone.

[0146] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. An aqueous-rich tunnel grouting slurry, characterized in that, The cement composite slurry is made of water glass and cement composite slurry, and the volume ratio of the cement composite slurry to water glass is (4-6):5; The water glass has a Baume degree of 30Bé-39Bé; The cement composite slurry comprises the following raw materials in parts by weight: ultra-fine portland cement 40 parts; filler 55-70 parts; water 48-82 parts; water reducing agent 0.4-1.2 parts; anti-erosion agent 0.5-1.5 parts; anti-cracking agent 1.3-2.7 parts; The anti-erosion agent comprises the following raw materials in parts by weight: basalt short fibers 10 parts; bagasse powder 1-3 parts; dicyclopentadiene 1.5-4.5 parts; insoluble polymer 3-8 parts; polymerization inhibitor 0.01 part; The preparation of the anti-erosion agent comprises the following steps: mixing dicyclopentadiene with bagasse powder uniformly, heating to 33-35℃, then adding basalt short fibers, stirring uniformly, then reducing to normal temperature, standing, oscillating, combing to obtain modified fibers; mixing insoluble polymer and polymerization inhibitor uniformly, adding modified fibers, heating to 31-33℃, constant temperature stirring for 10-20 min, reducing to normal temperature, standing, oscillating, dispersing to obtain anti-erosion agent; The anti-cracking agent comprises hydroxypropyl cellulose and ethylene-vinyl acetate copolymer, and the weight ratio of the hydroxypropyl cellulose to the ethylene-vinyl acetate copolymer is (16-17):

10.

2. A water-rich tunnel grouting slurry according to claim 1, characterized in that, The insoluble polymer is a low molecular weight insoluble polymer.

3. A water-rich tunnel grouting slurry according to claim 2, characterized in that, The insoluble polymer is selected from one of low molecular weight polycaprolactone, low molecular weight polyurethane elastomer and low molecular weight polytetrafluoroethylene.

4. A water-rich tunnel grouting slurry according to claim 1, characterized in that, The polymerization inhibitor is selected from hydroquinone.

5. The water-rich tunnel grouting slurry according to claim 1, characterized in that, The filler comprises mineral slag, fly ash and sodium-based bentonite, and the weight ratio of the mineral slag, fly ash and sodium-based bentonite is (8-60):(57-210):

5.

6. A process for grouting of water rich tunnels, characterized by, The water-rich tunnel grouting slurry is used for grouting by using the forward deep hole grouting process.

7. The water-rich tunnel grouting process according to claim 6, characterized in that, The initial grouting pressure is 0.9-1 MPa, the final grouting pressure is 0.2-0.3 MPa, the grouting speed is 20-40 L / min, and the length of the forward sectional grouting is 2-3 m.

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