Construction method based on preparation of ultra-fast setting-fast setting-slow setting double-liquid grouting material

Abstract

The invention discloses a construction method based on preparation of an ultrafast setting-fast setting-slow setting double-liquid grouting material. The construction method comprises the following steps: 1) respectively performing grouting plugging in three modes of ultrafast setting, fast setting and slow setting according to actual working condition requirements; (2) when the rapid plugging working condition needs to be met, phosphoric acid-water glass pre-gelatinization is conducted at the first position of the Y-shaped pipe, then pre-gelatinized slurry and cement are mixed to the third position of the Y-shaped pipe, and the gelatinization time is shorter than 15 s; (3) when a curtain grouting reinforcement working condition is needed, water glass slurry and cement are mixed to three positions of the Y-shaped pipe, a proper amount of conventional inorganic salt additives are added, and the gelling time is 25-50 s; and 4) when weak surrounding rock and a permeable rock-soil layer need to be subjected to grouting reinforcement, phosphoric acid is dissolved in water and converged in a second Y-shaped pipe, then the phosphoric acid and cement are prepared into cement grout, then the cement grout and water glass grout are mixed into a third Y-shaped pipe, and the gelling time is longer than 60s. The method has the advantages that the usage amount of additives is reduced, and the full-coverage grouting effect from ultrafast setting to slow setting is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of building materials, tunnels and underground engineering construction, and in particular relates to a construction method based on the preparation of ultra-fast setting-fast setting-slow setting cement-water glass double liquid grouting material. Background Art

[0002] In recent years, with the construction of a large number of tunnel and underground engineering projects, the hydrogeological conditions encountered in the construction of tunnel and underground engineering have become increasingly complex, especially the frequent occurrence of geological disasters such as water inrush, mud inrush and landslide. Compared with other geological disasters, the casualties, economic losses and construction delays caused by water inrush or mud inrush events are more serious. Therefore, the development of efficient plugging and reinforcement materials and grouting technology has become one of the key scientific issues in preventing and controlling water inrush disasters in tunnel and underground engineering.

[0003] Among them, the cement-water glass double liquid slurry system shows significant advantages in seepage fields and medium and low velocity dynamic water environments, including high water retention rate, excellent environmental compatibility, suitable and adjustable stone strength and low cost. It has been widely used in domestic tunnels and underground projects, especially in the field of synchronous grouting of shield tunnels and underground projects. However, the existing cement-water glass double liquid slurry has a relatively long setting time in a specific water-rich driving water environment, and cannot meet the ultra-fast solidification requirements in emergency operations. Although the industry has developed and applied some accelerating admixtures, their high cost and complex construction technology requirements have limited large-scale application. Therefore, it is urgent to develop a system solution with rapid setting performance, simple operation and low cost to meet the different setting time requirements under different working conditions.

[0004] At present, there are many patent documents that disclose synchronous grouting materials with controllable operation time and good construction performance. For example, Publication No. CN117303807A invented a new type of two-component shield synchronous grouting material and its preparation method. By introducing admixtures such as water reducers and modifiers, a faster setting time and a higher stone rate are achieved, and it has good durability. However, this system cannot achieve ultra-fast solidification when responding to emergency rescue conditions, and the diversity of admixtures and complex construction operation steps lead to rising costs and cumbersome operations. Publication No. CN108716405B invented a double-liquid grouting construction method for tunnel and underground engineering construction. By adding organic admixtures such as polyacrylic acid to cement slurry and adding inorganic admixtures such as calcium sulfate to water glass solution, a "fast-setting" double-liquid slurry is mixed and prepared for water blocking and reinforcement of water-rich soft rock tunnels and underground engineering. However, a large amount of organic admixtures are used in this method, and the admixtures contain potassium dichromate, a toxic and carcinogenic strong oxidant, which poses a great risk of environmental pollution. In addition, the combination of multiple admixtures used makes the process complicated and difficult to use universally on construction sites. Publication No. CN116877102A discloses a shield machine excavation construction method suitable for uneven soft and hard strata with upper sand and lower rock, in which water glass-phosphoric acid double slurry is used as drilling water-stopping slurry to temporarily stop water when dealing with sudden water in advance drilling construction. However, the core protection object of this invention is the shield machine, and it does not involve key technologies such as the setting time, mix design and construction process of the "superfast setting-fast setting-slow setting" grouting material of the cement-water glass-phosphoric acid ternary system. Summary of the invention

[0005] The purpose of the present invention is to solve the problem of water leakage and gushing in the cracks of existing water-rich tunnels and underground projects. It provides a preparation method of ultra-fast setting-fast setting-slow setting double-liquid grouting material, reduces the amount of admixture used, and improves the adaptability of cement-water glass grouting materials under different construction conditions. It can achieve full coverage grouting effects from "ultra-fast setting" to "slow setting" in seepage fields, static water, and specific water-rich driven water environments, ensuring efficient water blocking under different working conditions.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material includes the following specific steps: (1) According to the actual working conditions, choose to open the corresponding valve and perform grouting plugging in three ways: "ultra-fast setting", "fast setting" and "slow setting"; (2) When it is necessary to meet the needs of rapid plugging conditions such as sudden water inrush in tunnels and underground projects and emergency grouting in underground projects, first pre-gelatinize phosphoric acid-water glass at one point of the Y-shaped tube, and then mix the pre-gelatinized phosphoric acid-water glass slurry with cement at three points of the Y-shaped tube. The mixed slurry is used for "super-fast setting" grouting and plugging, and the gelling time is less than 15 seconds; (3) When curtain grouting reinforcement is required, water glass slurry is directly mixed with cement at three locations of the Y-shaped pipe. The mixed slurry is used for "fast setting" grouting and plugging. By adding an appropriate amount of conventional inorganic salt admixtures, the gelling time can be adjusted within 25s~50s; (4) When grouting reinforcement is required for weak surrounding rock and permeable rock and soil layers, phosphoric acid is first dissolved in water and gathered at the second Y-type tube, then mixed with cement to make cement slurry, and then the cement slurry is mixed with water glass slurry and added to the third Y-type tube. The mixed slurry is used for "slow setting" grouting and plugging, and the gelling time can be achieved> 60s; (5) After grouting and plugging in different ways according to actual working conditions, the "ultra-fast setting" grouting slurry described in step 2 is used again to seal the hole, which can reduce or avoid slurry backflow.

[0007] Furthermore, in step (2), the cement is any one of ordinary Portland cement and low-alkali Portland cement, and its strength grade is not less than grade 32.5.

[0008] Furthermore, in the step (2), the Baume degree of the water glass is 38-45 Bé, the modulus is 2.5-3.3, and the Baume degree of the water glass after dilution with deionized water is 26-34 Bé.

[0009] Furthermore, in step (2), the concentration of the original phosphoric acid solution is 85wt%, and the concentration of the phosphoric acid solution after dilution with deionized water is 10wt%~20wt%.

[0010] Furthermore, in the step (2), in the "ultra-fast setting" cement-water glass two-liquid grouting material, the phosphoric acid-water glass "pre-gelatinized" mix ratio is 30-50 parts of deionized water, 15-25 parts of phosphoric acid solution, 60-80 parts of cement, and 15-25 parts of water glass.

[0011] Furthermore, in the step (2), the key to the "superfast setting" cement-water glass double liquid grouting material phosphoric acid-water glass "pre-gelling" construction method is: first, water and cement are prepared into ordinary cement slurry at a water-cement ratio of 0.6-0.8; secondly, phosphoric acid and water glass solution are mixed at one point of the Y-shaped tube to achieve pre-gelling in the subsequent pipeline; finally, the pre-gelled slurry is mixed with the above-mentioned ordinary cement slurry at three points of the Y-shaped tube to prepare the superfast setting grouting slurry. This process requires that the length of the pipeline through which the "pre-gelled" slurry and the "superfast setting" grouting slurry flow is as short as possible to ensure that the grouting pipeline is unobstructed and free from blockage.

[0012] Furthermore, in step (3), the "fast-setting" cement-water glass two-liquid grouting material is prepared in the following proportions: 30-50 parts of deionized water, 50-70 parts of cement, 30-50 parts of water glass, and 0.2-0.4 parts of one or more conventional inorganic salt admixtures such as aluminum chloride, sodium sulfate or water reducing agent, so that the gelling time is controlled within 25s to 50s.

[0013] Furthermore, in step (3), the key to the construction method of the "fast-setting" cement-water glass double liquid grouting material is: firstly, dissolving one or more conventional inorganic salt admixtures of aluminum chloride, sodium sulfate and water reducer in water, and mixing with cement at a water-cement ratio of 0.6 to 0.8 to prepare cement slurry, and then mixing the slurry with water glass solution at a volume ratio of 1:1 to prepare "fast-setting" grouting slurry.

[0014] Furthermore, in step (4), the mix ratio of the "slow-setting" cement-water glass double liquid grouting material is 30-50 parts of deionized water, 0.1-0.5 parts of phosphoric acid solution, 50-70 parts of cement, and 30-50 parts of water glass.

[0015] Furthermore, in step (4), the key to the construction method of the "slow-setting" cement-water glass double liquid grouting material is: firstly, dissolving the phosphoric acid solution in water according to the number of parts, mixing it with cement at a water-cement ratio of 0.6 to 0.8 to prepare a cement slurry, and then mixing the slurry with the water glass solution at a volume ratio of 1:1 to prepare a "slow-setting" grouting slurry.

[0016] Furthermore, in step (5), the key to performing interactive grouting and plugging in different ways according to actual working conditions is that under dynamic water conditions, "ultra-fast setting" grouting slurry can be used to form a three-dimensional closed space, and the dynamic water in the space will evolve into static water, and then be filled with "slow setting" grouting slurry to achieve a "hole sweeping" effect.

[0017] Compared with the prior art, the advantages of the technical solution of the present invention are: (1) The present invention can achieve the effect of "super-fast setting", "fast setting" or "slow setting" of the cement-water glass double liquid grouting time by adjusting the different chemical reactions of phosphoric acid in the cement-water glass system and only by adding phosphoric acid as a setting regulating admixture, indicating the "double effect" of phosphoric acid in the cement-water glass double liquid grouting material. The mechanism of its "super-fast setting" grouting effect is to adjust the concentration of phosphoric acid solution so that the phosphoric acid solution and the water glass solution are mixed with each other, and the slurry can be gelled in the acidic zone and the neutral acidic zone, thereby making the phosphoric acid-water glass solution "pre-gelled". According to the principle of strong acid preparing weak acid, phosphoric acid can react with sodium silicate in sodium water glass to generate metasilicic acid and sodium phosphate, as shown in formula (1-1):

[0018] Under acidic conditions, metasilicic acid promotes its transformation into orthosilicic acid through hydration, and its chemical equation is shown in formula (1-2):

[0019] However, under different pH acidic conditions, H + or OH - All of them can catalyze the polycondensation reaction of orthosilicic acid, thus achieving the "pre-gelation" phenomenon of water glass. When the solution pH is less than 2, the excess H + An equilibrium state is established with orthosilicic acid, causing the orthosilicic acid to be temporarily protonated and positively charged. The chemical equation is shown in formula (1-3):

[0020] The positively charged orthosilicic acid will form Si-O-Si bonds with the orthosilicic acid generated in the solution, namely siloxane bridges, and the siloxane bridges will also form long polysiloxane chains or network structures through dehydration condensation reactions between hydroxyl groups, thereby forming a gel. The chemical equation is shown in formula (1-4):

[0021] The extra protons on the long chain or network structure of polysiloxane will be transferred to water molecules or other orthosilicic acid molecules, further promoting the dehydration condensation reaction; When the pH value of the solution is between 2 and 7, the orthosilicic acid partially deprotonates and ionizes to form H3SiO4 - The chemical equation of isocyanate is shown in formula (1-5):

[0022] Subsequently, it reacts with other orthosilicic acid to form a long chain or network structure of polysiloxane, thereby forming a gel. The chemical equation is shown in formula (1-6):

[0023] The above is the reaction mechanism of the phosphoric acid-water glass system mix design and different "pre-gelation" gel time designs. During the mixing process, the Ca(OH)2 formed by cement hydration after adding cement slurry as an alkaline solution will further regulate the gel formation and coagulation time of the phosphoric acid-water glass "pre-gelation" system, thereby realizing the preparation of "super-fast setting" cement-water glass grouting materials.

[0024] The mechanism of action of the "fast setting" cement-water glass grouting material of the present invention is as follows: The main components of cement are tricalcium silicate and dicalcium silicate, which react with water to form hydrated calcium silicate gel and calcium hydroxide. The chemical equation is shown in formula (1-7) with C3S as an example:

[0025] The main component of water glass is sodium silicate, and the solution is alkaline. In the strong alkaline environment of water glass, the hydration product calcium hydroxide in cement reacts with the sodium silicate in water glass to form a stable hydrated calcium silicate gel. The chemical equation is shown in formula (1-8):

[0026] As the hydration reaction proceeds, the CSH gel gradually precipitates from the solution and forms a network structure with gelling properties. At the same time, the consumption of Ca(OH)2 promotes the hydration reaction of tricalcium silicate and dicalcium silicate in the cement, and these reactions further accelerate the formation of hydrated calcium silicate. As the content of hydrated calcium silicate increases, the fluidity of the slurry gradually decreases and finally solidifies. The reaction is very rapid, causing the slurry system to coagulate rapidly, achieving a "fast-setting" grouting effect. The addition of inorganic salt admixtures will affect the cement hydration reaction rate, thereby further achieving the control of the setting time.

[0027] The mechanism of action of the "slow setting" cement-water glass grouting material of the present invention is as follows: First, phosphoric acid reacts with Ca(OH)2 in the cement hydration product in the cement-water glass system. 2+ A chemical reaction occurs to generate insoluble calcium phosphate precipitate. The chemical equation is shown in formula (1-9):

[0028] The formation of calcium phosphate reduces the concentration of free calcium ions in the slurry, thereby inhibiting the reaction of Ca(OH)2 with water glass to form CSH gel. These precipitates will adhere to the surface of cement particles to form a passivation film, thereby delaying the further hydration reaction of cement and delaying the gelation time.

[0029] (2) The cross double-liquid grouting method with adjustable "ultra-fast setting-fast setting-slow setting" grouting of the present invention is simple to prepare on-site materials. It can realize grouting reinforcement and emergency plugging of tunnels and underground projects by only rationally proportioning the three materials of conventional phosphoric acid, water glass and cement and regulating the construction process. It has the advantages of simple operation and simple construction process. At the construction site, a single grouting system can realize differentiated regulation of different gelling times, without the need for large-scale transformation of the grouting site, avoiding the problem of emergency plugging grouting for workers in special working conditions such as sudden water plugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a grouting process flow chart of the ultra-fast setting-fast setting-slow setting double liquid grouting material of the present invention; Figure 2 The XRD spectrum of the "ultra-fast setting-fast setting-slow setting" cement-water glass double liquid grouting material consolidation body prepared for this embodiment for 7 days; Figure 3 for Figure 2 An enlarged view of a node at calcium phosphate in the XRD pattern shown; Figure 4 for Figure 2 The enlarged view of the node at C2S+C3S in the XRD pattern shown; Figure 5 This is an enlarged view of the node about hydroxyapatite in the XRD pattern shown. DETAILED DESCRIPTION Example 1

[0031] To make the present invention more clear, the construction method based on the preparation of ultra-fast setting-fast setting-slow setting double-liquid grouting material of the present invention is further described below in conjunction with the accompanying drawings. The specific embodiments described here are only used to explain the present invention and are not used to limit the present invention.

[0032] like Figure 1 As shown, it is a flow chart of the preparation of the ultra-fast setting-fast setting-slow setting double liquid grouting material of the present invention, which includes a water glass storage tank 1, a phosphoric acid storage tank 2, a water storage tank 3 and a cement storage tank 4 that cooperate with each other, and the four storage tanks contain four materials, namely water glass, phosphoric acid, water and cement; The outlet of the water glass storage tank 1 is connected to a delivery pipe 1 5 and a valve 1 51 is connected to the pipe. The outlet of the phosphoric acid storage tank 2 is connected to a delivery pipe 2 6 and a delivery pipe 3 7, and the delivery pipes 2 and 3 are connected to valves 2 61 and 3 71, respectively. The outlet of the water storage tank 3 is connected to a delivery pipe 8 4 and a valve 4 81 is connected to the pipe. The outlet of the cement storage tank 4 is connected to a delivery pipe 5 9 and a valve 5 91 is connected to the pipe. The delivery pipe 1 5 and the delivery pipe 2 6 meet at the Y-shaped pipe 1 10, the delivery pipe 3 7 and the delivery pipe 4 8 meet at the Y-shaped pipe 2 11, and the Y-shaped pipe 2 11 and the delivery pipe 5 9 are both connected to the mixer 13, and the mixer 13 is further connected to the inlet of the grouting machine 14 through a pipeline, the Y-shaped pipe 10 is also connected to the inlet of the grouting machine 14, and the outlet of the grouting machine 14 is connected to the grouting port 15 through the Y-shaped pipe 3 12.

[0033] In this embodiment, a "superfast setting" cement-water glass two-liquid grouting material is provided, which includes the following components and preparation methods by mass and volume: (1) Weigh 23.33 g of water and 5 g of 85 wt% phosphoric acid, mix them to prepare a 15 wt% phosphoric acid solution, and then quantify 20 mL; (2) Weigh 42 g of water and 70 g of cement, pour the cement into the water, and then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (3) Quantitatively add 20 mL of 30° Bé water glass solution; (4) mixing the solutions of step (1) and step (3) in different orders at a volume ratio of 1:1, and then stirring at a speed of 240 r / min for 3 to 4 seconds to prepare liquid A; (5) The cement slurry B prepared in step (2) is mixed with liquid A in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 5 to 10 seconds to make them evenly mixed, thereby preparing an "ultra-fast setting" cement-water glass two-liquid grouting material. According to the JC / T2536-2019 cement-water glass grouting material standard, the gelling time is tested using the inverted cup method, and the data are shown in Table 1. Example 2

[0034] A "superfast setting" cement-water glass double liquid grouting material, measured by mass and volume, includes the following components and preparation method: (1) Weigh 23.33 g of water and 5 g of 85 wt% phosphoric acid and mix them to prepare a 15 wt% phosphoric acid solution; then quantify 20 mL; (2) Weigh 42 g of water and 60 g of cement, pour the cement into the water, and then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (3) Quantitatively add 20 mL of 30° Bé water glass solution; (4) mixing the solutions of step (1) and step (3) in different orders at a volume ratio of 1:1, and then stirring at a speed of 240 r / min for 3 to 4 seconds to prepare liquid A; (5) The cement slurry B prepared in step (2) is mixed with liquid A in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 5 to 10 seconds to make them evenly mixed, thereby preparing an "ultra-fast setting" cement-water glass two-liquid grouting material. According to the JC / T2536-2019 cement-water glass grouting material standard, the gelling time is tested using the inverted cup method, and the data are shown in Table 1. Example 3

[0035] A "superfast setting" cement-water glass double liquid grouting material, measured by mass and volume, includes the following components and preparation method: (1) Weigh 23.33 g of water and 5 g of 85 wt% phosphoric acid and mix them to prepare a 15 wt% phosphoric acid solution; then quantify 20 mL; (2) Weigh 40 g of water and 50 g of cement, pour the cement into the water, and then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (3) Quantitatively add 20 mL of 30° Bé water glass solution; (4) mixing the solutions of step (1) and step (3) in different orders at a volume ratio of 1:1, and then stirring at a speed of 240 r / min for 3 to 4 seconds to prepare liquid A; (5) The cement slurry B prepared in step (2) is mixed with liquid A in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 5 to 10 seconds to make them evenly mixed, thereby preparing an "ultra-fast setting" cement-water glass two-liquid grouting material. According to the JC / T2536-2019 cement-water glass grouting material standard, the gelling time is tested using the inverted cup method, and the data are shown in Table 1. Example 4

[0036] A "superfast setting" cement-water glass double liquid grouting material, measured by mass and volume, includes the following components and preparation method: (1) Weigh 23.33 g of water and 5 g of 85 wt% phosphoric acid and mix them to prepare a 15 wt% phosphoric acid solution; then quantify 20 mL; (2) Weigh 40 g of water and 50 g of cement, pour the cement into the water, and then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (3) Quantitatively add 20 mL of 34° Bé water glass solution; (4) mixing the solutions of step (1) and step (3) in different orders at a volume ratio of 1:1, and then stirring at a speed of 240 r / min for 3 to 4 seconds to prepare liquid A; (5) The cement slurry B prepared in step (2) is mixed with liquid A in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 5 to 10 seconds to make them evenly mixed, thereby preparing an "ultra-fast setting" cement-water glass two-liquid grouting material. According to the JC / T2536-2019 cement-water glass grouting material standard, the gelling time is tested using the inverted cup method, and the data are shown in Table 1. Example 5

[0037] A "fast-setting" cement-water glass double liquid grouting material, measured by mass and volume, includes the following components and a preparation method: (1) Weigh 42 g of water and 60 g of cement, pour the cement into the water, and then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (2) Quantitatively prepare 40 mL of 30° Bé water glass solution as liquid A; (3) The solutions of step (1) and step (2) are mixed in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 10 to 15 seconds to make them evenly mixed, thereby preparing a "fast-setting" cement-water glass two-liquid grouting material. The grouting material is tested for its gelling time by the inverted cup method according to the JC / T2536-2019 cement-water glass grouting material standard, and the data are shown in Table 1. Example 6

[0038] A "fast-setting" cement-water glass double liquid grouting material, measured by mass and volume, includes the following components and a preparation method: (1) Weigh 42g of water and 0.35g of inorganic salt additive (such as sodium sulfate), and dissolve them in water; (2) Weigh 70 g of cement and pour it into the aqueous solution in step 1, then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (3) Quantitatively prepare 40 mL of 30° Bé water glass solution as liquid A; (4) The solutions of step (2) and step (3) are mixed in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 10 to 15 seconds to make them evenly mixed, thereby preparing a "fast-setting" cement-water glass two-liquid grouting material. According to the JC / T2536-2019 cement-water glass grouting material standard, the gelling time is tested using the inverted cup method, and the data are shown in Table 1. Example 7

[0039] A "slow-setting" cement-water glass double liquid grouting material, measured by mass and volume, includes the following components and a preparation method: (1) Weigh 40 g of water and 0.125 g of 85 wt % phosphoric acid, mix them, and prepare a phosphoric acid solution; (2) Weigh 50 g of cement and pour it into the phosphoric acid solution. Then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (3) Quantitatively prepare 40 mL of 34° Bé water glass solution as liquid A; (4) Liquid A and liquid B in step (2) and step (3) are mixed in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 20 to 30 seconds to make them evenly mixed, thereby preparing a "slow-setting" cement-water glass two-liquid grouting material. According to the JC / T2536-2019 cement-water glass grouting material standard, the gelling time is tested using the inverted cup method, and the data are shown in Table 1. Example 8

[0040] A "slow-setting" cement-water glass double liquid grouting material, measured by mass and volume, includes the following components and a preparation method: (1) Weigh 42 g of water and 0.125 g of 85 wt% phosphoric acid, mix them, and prepare a phosphoric acid solution; (2) Weigh 60 g of cement and pour it into the phosphoric acid solution. Then stir the two at a speed of 1000 r / min for 6 min to ensure that the prepared cement slurry B is uniform; (3) Quantitatively prepare 40 mL of 30° Bé water glass solution as liquid A; (4) Liquid A and liquid B in step (2) and step (3) are mixed in a volume ratio of 1:1, and then stirred at a speed of 240 r / min for 20 to 30 s to make them evenly mixed, thereby preparing a slow-setting cement-water glass two-liquid grouting material. According to the JC / T2536-2019 cement-water glass grouting material standard, the gelling time is tested by the inverted cup method, and the data are shown in Table 1.

[0041] The gelling time of different mix ratios and different construction processes is shown in Table 1:

[0042] It can be seen from Table 1 that different grouting effects of "super-fast setting-fast setting-slow setting" can be achieved by adjusting the dosage and mix ratio of phosphoric acid, the mixing order of phosphoric acid solution, water glass and cement slurry, and the construction process.

[0043] Figure 2 This is the XRD spectrum of the "ultra-fast setting-fast setting-slow setting" cement-water glass double liquid grouting material solidified body prepared in the embodiment for 7 days. Figure 2It can be seen that after 7 days of standard curing, the hydration products of the "ultra-fast setting" and "slow setting" test blocks mainly include hydration products such as calcium carbonate, CSH, calcium hydroxide, calcium sulfonate, calcium phosphate and hydroxyapatite; while the hydration products of the "fast setting" test block are mainly hydration products such as calcium carbonate, CSH, calcium hydroxide and calcium sulfonate. In addition, due to the reaction of water glass with cement slurry, the diffraction peaks of C3S and C2S are lower in all embodiments, indicating that water glass promotes the cement hydration reaction, especially increases the hydration reaction rate of C3S and C2S in cement. The specific mechanism is shown in formula (1-9).

[0044] Further by Figures 3-5 It can be seen that although the types of hydration products of the "ultra-fast setting" and "slow setting" specimens are the same, calcium phosphate, hydroxyapatite and other mineral phases are formed, and their C3S and C2S diffraction peaks are relatively high, the gelation rates of the two show completely opposite trends. The main reason for this phenomenon is that in the "slow setting" system, phosphoric acid is added to the cement slurry, resulting in the formation of a large number of mineral phases such as calcium phosphate and hydroxyapatite in the slurry, and attached to the surface of C3S and C2S, which slows down the hydration reaction rate of cement. In the "ultra-fast setting" system, phosphoric acid is first added to the water glass solution to form a "pre-gelatinized" slurry, and then mixed with the cement slurry. Although calcium phosphate, hydroxyapatite and other mineral phases are also formed in this process, and the hydration reaction rate of cement is slowed down. However, the "pre-gelatinization" effect caused by ion catalysis plays a decisive role in shortening the gelation time of the entire system. The specific mechanism is shown in formulas (1-1) to (1-6).

[0045] In summary, the present invention discloses a preparation method and construction method of a "superfast setting-fast setting-slow setting" cement-water glass double liquid grouting material. The method introduces phosphoric acid as an admixture into the cement-water glass double liquid slurry system, and utilizes its silicate ion polymerization mechanism at different pH values ​​to achieve phosphoric acid to control the gelation time of the cement-water glass double liquid grouting material under different construction process conditions. Under actual grouting reinforcement or emergency plugging conditions, by utilizing the original grouting system on site and setting three Y-shaped pipes in the grouting pipeline, the gelation time can be controlled to meet the requirements of various water plugging reinforcement conditions for tunnels and underground projects. The method reduces the difficulty of material preparation on the construction site, has low difficulty in training construction personnel, and achieves a full coverage grouting effect from "superfast setting" to "fast setting" to "slow setting" in the seepage field, static water, and specific water-rich driving water environment, greatly improving the response speed of the grouting process, especially in large-scale sudden water rescue operations.

[0046] In addition, the three-Y-tube single-set system has high flexibility and adaptability in design. It can not only quickly adjust the coagulation characteristics of the slurry according to different construction requirements, but also significantly reduce construction costs and equipment maintenance difficulties. The system does not require complicated operating procedures, and can achieve precise control of the slurry coagulation time through simple parameter adjustments, ensuring the controllability of the grouting process and construction safety. The present invention has important breakthroughs in the simplification of material formulations, optimization of process flows, and cost control, and provides a new technical solution for the widespread application of cement-water glass double-liquid grouting systems under different hydrogeological conditions. It is particularly suitable for emergency rescue and reinforcement operations such as transportation tunnels, hydraulic tunnels, mines, and deep space engineering reinforcement.

[0047] The idea and method of preparing and constructing the "ultra-fast setting-fast setting-slow setting" cement-water glass double liquid grouting material of the present invention are suitable for various application scenarios such as top water grouting, curtain grouting and anchor grouting in tunnel and underground engineering construction. There are many methods and ways to implement this technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the scope of protection of the present invention. All components not specified in this embodiment can be implemented using existing technologies.

[0048] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material, characterized in that: Step 1: According to the actual working conditions, choose to open the corresponding valve and perform grouting plugging in three ways: "ultra-fast setting", "fast setting" and "slow setting"; Step 2: When it is necessary to meet the needs of rapid plugging conditions such as sudden water inrush in tunnels and underground projects and emergency grouting in underground projects, first pre-gelatinize phosphoric acid-water glass at the Y-type tube 1 (10), and then mix the pre-gelatinized phosphoric acid-water glass slurry with cement and add it to the Y-type tube 3 (12). The mixed slurry is used for "super-fast setting" grouting and plugging, and the gelling time is less than 15s; Step 3: When curtain grouting reinforcement is required, water glass slurry is directly mixed with cement and added to the Y-shaped pipe 3 (12). The mixed slurry is used for "fast setting" grouting and plugging. By adding an appropriate amount of conventional inorganic salt admixtures, the gelling time can be adjusted within 25s~50s; Step 4: When grouting reinforcement is required for weak surrounding rock and permeable rock and soil layers, firstly, phosphoric acid is dissolved in water and collected at the Y-type tube 2 (11), and then mixed with cement to form cement slurry. Then, the cement slurry is mixed with water glass slurry and poured into the Y-type tube 3 (12). The mixed slurry is used for "slow setting" grouting and plugging, and the gelling time can be achieved> 60s; Step 5: According to the actual working conditions, different methods of interactive grouting and plugging can be carried out, and finally the "ultra-fast setting" grouting slurry described in step 2 can be used to seal the hole. Among them, the key to performing different methods of interactive grouting and plugging is to first use the "ultra-fast setting" grouting slurry to form a three-dimensional closed space under dynamic water conditions. The dynamic water in the space will evolve into static water, and then fill it with "slow setting" grouting slurry to achieve a "hole sweeping" effect.

2. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1 is characterized in that: In the step 2, the cement is any one of ordinary silicate cement and low-alkali silicate cement, and its strength grade is not less than grade 32.

5.

3. The construction method based on the preparation of ultrafast-setting-fast-setting-slow-setting double-liquid grouting material according to claim 1 is characterized in that: In the step 2, the Baume degree of the water glass is 38-45 Bé, and the modulus is 2.5-3.

3. After being diluted with deionized water, the Baume degree of the water glass is 26-34 Bé.

4. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1 is characterized in that: In the step 2, the concentration of the original phosphoric acid solution is 85wt%, and the concentration of the phosphoric acid solution after dilution with deionized water is 10wt%-20wt%.

5. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1 is characterized in that: In the step 2, in the "ultra-fast setting" cement-water glass two-liquid grouting material, the phosphoric acid-water glass "pre-gelatinized" mix ratio is 30-50 parts of deionized water, 15-25 parts of phosphoric acid solution, 60-80 parts of cement, and 15-25 parts of water glass.

6. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1 is characterized in that: In step 2, the key to the "superfast setting" cement-water glass double liquid grouting material phosphoric acid-water glass "pre-gelling" construction method is: first, water and cement are prepared into ordinary cement slurry at a water-cement ratio of 0.6-0.8; second, phosphoric acid and water glass solution are mixed at Y-tube one (10) to achieve pre-gelling in the subsequent pipeline; finally, the pre-gelled slurry is mixed with the above-mentioned ordinary cement slurry at Y-tube three (12) to prepare ultrafast setting grouting slurry. This process requires that the length of the pipeline through which the "pre-gelled" slurry and the "superfast setting" grouting slurry flow is as short as possible to ensure that the grouting pipeline is unobstructed and avoid blockage.

7. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1 is characterized in that: In the step 3, the "fast setting" cement-water glass two-liquid grouting material is prepared in the following proportions: 30-50 parts of deionized water, 50-70 parts of cement, 30-50 parts of water glass, and 0.2-0.4 parts of one or more conventional inorganic salt admixtures such as aluminum chloride, sodium sulfate or water reducing agent, so that the gelling time is controlled within 25s to 50s.

8. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1, characterized in that: In the step 3, the key to the construction method of the "fast-setting" cement-water glass double-liquid grouting material is: firstly, dissolving one or more conventional inorganic salt admixtures of aluminum chloride, sodium sulfate and water reducer in water, and mixing with cement at a water-cement ratio of 0.6 to 0.8 to prepare cement slurry, and then mixing the slurry with water glass solution at a volume ratio of 1:1 to prepare "fast-setting" grouting slurry.

9. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1, characterized in that: In the step 4, the mix ratio of the "slow-setting" cement-water glass double liquid grouting material is 30-50 parts of deionized water, 0.1-0.5 parts of phosphoric acid solution, 50-70 parts of cement, and 30-50 parts of water glass.

10. The construction method based on the preparation of ultra-fast setting-fast setting-slow setting double liquid grouting material according to claim 1, characterized in that: The key to the construction method of the "slow-setting" cement-water glass double liquid grouting material is: first, dissolve the phosphoric acid solution in water according to the number of parts, mix it with cement at a water-cement ratio of 0.6-0.8 to prepare a cement slurry, and then mix the slurry with the water glass solution at a volume ratio of 1:1 to prepare a "slow-setting" grouting slurry, which can delay the gelation time compared to step three.

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