Preparation method of anti-dispersion grouting material for shield synchronous grouting
The grouting material prepared through specific proportions and mixing processes solves the problem of grouting material dispersion and loss during shield construction, realizes efficient construction in areas with abundant groundwater, and improves project quality and tunnel sealing.
Patent Information
- Application Number
- CN202511096879.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-06
- Publication Date
- 2025-10-17
AI Technical Summary
During shield construction, high groundwater pressure causes grouting material segregation and cementitious material loss, affecting project quality. Existing technology requires dewatering measures, which increases costs and construction time.
By using cementitious materials, aggregates and additives in a specific proportion, mixing them in multiple directions and spraying water mist and high-pressure gas, a dense and flexible network structure is formed to enhance the viscosity of the grouting material and the protective film to prevent dispersion.
In areas with abundant groundwater, no precipitation measures are required, which improves construction quality and sealing, shortens construction period and reduces costs.
Smart Images
Figure CN120794501A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of grouting materials, in particular to a preparation method of a grouting material for anti-dispersion synchronous grouting of a shield. BACKGROUND
[0002] Synchronous grouting of a shield refers to a construction technology of injecting grout into the gap between a lining ring and a stratum through a shield tail grouting pipe during shield tunneling construction.
[0003] At present, in an area rich in underground water, before shield tunneling construction, dewatering measures need to be taken to ensure normal construction, which not only increases construction technology and equipment, but also prolongs the construction period and increases the construction cost. SUMMARY
[0004] The application aims to provide a preparation method of a grouting material for anti-dispersion synchronous grouting of a shield, and aims to solve the problem of grouting material segregation and loss during shield tunneling construction in the prior art.
[0005] The application is implemented in the following manner.
[0006] 1. Provide cementing material, aggregate, additive and water, and the mass ratio of the cementing material, aggregate, additive and water is (20-40):(60-80):(0.1-0.5):(0.1-50);
[0007] The cementing material is formed by stirring and mixing portland cement, fly ash, mineral powder, gypsum and stone powder, the aggregate is formed by stirring and mixing sand and sand washing mud generated during shield construction, and the additive comprises anti-dispersing agent and retarder, wherein the anti-dispersing agent comprises methyl cellulose, polyacrylamide, silica ash and polycarboxylic acid water reducing agent.
[0008] 2. The cementing material, aggregate and additive are sequentially added into a stirring cylinder for multidirectional stirring and mixing, and water is continuously injected into the stirring cylinder during the stirring and mixing process, and the cementing material, aggregate, additive and water are stirred and mixed to form the grouting material for anti-dispersion synchronous grouting of a shield.
[0009] Further, in the preparation step 1, the sand is natural sand or machine-made sand, the particle size of the sand is not greater than 2 mm, and the sand washing mud is mud generated by a shield sand washing line, and the mud contains fine sand, and the mud has a specific gravity of not less than 1.2.
[0010] Further, in the preparation step 1), the ratio of the sand washing mud and the sand is (1-5):(9-6) by mass.
[0011] Further, in the preparation step 1), the silicate cement is P·O42.5 grade, the fly ash is the second class F fly ash, the mineral powder has an activity grade not lower than S95 grade, the gypsum is dihydrate gypsum, and the stone powder is building stone powder or natural stone powder.
[0012] Further, in the preparation step 1), the cementitious material includes 10-30 parts of silicate cement, 30-50 parts of mineral powder, 10-20 parts of gypsum, 1-50 parts of fly ash, and 1-10 parts of stone powder by mass.
[0013] Further, in the preparation step 1), the ratio of the anti-dispersion agent and the retarder is (100-300):(1-4) by mass.
[0014] Further, in the preparation step 1), the anti-dispersion agent includes 8-10 parts of methyl cellulose, 1-4 parts of polyacrylamide, 50-70 parts of silica ash, and 10-20 parts of polycarboxylic acid water reducer by mass.
[0015] Further, in the preparation step 1), the retarder is sucrose or sodium gluconate.
[0016] Further, in the preparation step 2), the upper part of the stirring cylinder has a pneumatic stirring cavity, and the lower part of the stirring cylinder has a rotating stirring cavity provided with a stirring shaft; a partition plate is arranged between the pneumatic stirring cavity and the rotating stirring cavity, and the partition plate is provided with through holes penetrating the upper and lower parts; the inner side wall of the rotating stirring cavity is provided with water spraying pipes arranged along the circumferential direction of the rotating stirring cavity and spirally arranged along the axial direction of the rotating stirring cavity.
[0017] In the preparation step 2), the water spraying pipes spray water into the rotating stirring cavity to form a plurality of water mist layers, and then the cementitious material, the aggregate and the additive material are placed in the pneumatic stirring cavity, a flowing high-pressure gas is injected into the pneumatic stirring cavity, and the high-pressure gas drives the cementitious material, the aggregate and the additive material to be mixed in the pneumatic stirring cavity to form a mixed material.
[0018] In the process of pneumatic stirring and mixing of the mixed material in the pneumatic stirring cavity, the mixed material falls into the rotating stirring cavity through the through holes of the partition plate, passes through the plurality of water mist layers, and water is injected into the mixed material in multiple directions, the stirring shaft stirs and mixes the mixed material and the water to form the grouting material.
[0019] Further, the partition plate is upwardly convex and in a conical shape, a gas injection pipe is arranged on the inner side wall of the pneumatic stirring cavity, the gas injection pipe is arranged along the axial direction of the pneumatic stirring cavity and faces the partition plate;
[0020] In the preparation step 2), after the cementing material, the aggregate and the additive are placed in the pneumatic stirring cavity and located between the partition plate and the inner side wall of the pneumatic stirring cavity, the gas injection pipe injects the high-pressure gas in a slanting flow into the pneumatic stirring cavity, the high-pressure gas drives the cementing material, the aggregate and the additive to rotate along the circumferential direction of the pneumatic stirring cavity and to be stirred and mixed in the rotating process, thereby forming the mixed material, and the mixed material falls into the rotating stirring cavity through the through hole in the rotating process.
[0021] Compared with the prior art, the preparation method of the grouting material for anti-dispersion synchronous grouting of a shield provided by the application has the following advantages.
[0022] Secondly, the silicate cement is hydrated to generate hydrated calcium silicate and calcium hydroxide, the calcium hydroxide further reacts with the mineral powder and the fly ash to generate ettringite, thereby accelerating the hydration reaction of the system.
[0023] Further, the stone powder can further fill the voids and enhance the compactness of the system, and the calcium hydroxide gradually activates the activity of the mineral powder and the fly ash, thereby enhancing the late strength of the grouting material.
[0024] The grouting material has certain viscosity, and after being dissolved in the water, a flexible protective film is formed on the surface, which slows down the dispersion of the synchronous grouting material, effectively enhances the construction quality of the grouting material, prevents the water from penetrating, and avoids the segregation and loss of the grouting material.
[0025] In the area with rich underground water, the dewatering measure is not needed before the shield tunneling construction, thereby avoiding the increase of the construction process and equipment, shortening the construction period, reducing the construction cost, and improving the sealing performance of the shield tunnel. BRIEF DESCRIPTION OF DRAWINGS
[0026] Figure 1 is a flowchart of the preparation method of the grouting material for anti-dispersion synchronous grouting of a shield provided by the application;
[0027] Figure 2 is a schematic view of the inside of the stirring cylinder provided by the application;
[0028] Figure 3 is a test picture of the grouting material in the prior art placed in water;
[0029] Figure 4 is a test picture provided by the grouting material of the present application in water. DETAILED DESCRIPTION
[0030] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.
[0031] The implementation of the present application is described in detail below in combination with specific examples.
[0032] The same or similar reference numerals in the drawings of the present embodiment correspond to the same or similar components; in the description of the present application, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "left", "right" and the like is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the position relationship in the drawings are only used for exemplary illustration, and cannot be understood as a limitation of the present patent, for those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.
[0033] Referring to Figures 1-4 , a preferred embodiment provided by the present application.
[0034] The preparation method of the grouting material for anti-dispersion shield synchronous grouting comprises the following preparation steps:
[0035] 1) Provide cementing material, aggregate, additive and water body respectively, and the proportion of cementing material, aggregate, additive and water body is (20-40):(60-80):(0.1-0.5):(0.1-50) according to the mass ratio;
[0036] The cementing material is formed by stirring and mixing portland cement, fly ash, mineral powder, gypsum and stone powder, the aggregate is formed by stirring and mixing sand and sand washing mud generated in shield construction; the additive includes anti-dispersing agent and retarder, the anti-dispersing agent includes methyl cellulose, polyacrylamide, silica ash and polycarboxylic acid water reducing agent.
[0037] 2) The cementing material, aggregate and additive are sequentially added to the stirring drum 100 for multidirectional stirring and mixing, and the water body is continuously injected into the stirring drum 100 in multiple directions during the stirring and mixing process, and the cementing material, aggregate, additive and water body are stirred and mixed to form the grouting material for anti-dispersion shield synchronous grouting.
[0038] In the above-mentioned method for preparing the grouting material used for anti-dispersion shield synchronous grouting, during the stirring and mixing process of the cementitious material, aggregate, additives and water, polyacrylamide and methyl cellulose work synergistically, forming hydrogen bonds with water molecules through the hydroxyl functional groups, and the molecules attract each other, forming a dense and flexible network structure on the surface of the grouting material, which wraps the grouting material and achieves the effect of preventing it from dispersing underwater.
[0039] Secondly, silicate cement hydrates to form hydrated calcium silicate and calcium hydroxide, which then undergoes a secondary hydration reaction with mineral powder and fly ash. The aluminum and calcium phases in the grouting material react with gypsum to form ettringite, accelerating the hydration reaction of the system.
[0040] Furthermore, stone powder can further fill the gaps and enhance the density of the system, while calcium hydroxide gradually stimulates the activity of mineral powder and fly ash, thus enhancing the later strength of the grouting material.
[0041] The grouting material has a certain viscosity. After dissolving in water, it will form a flexible protective film on the surface, slowing down the dispersion of the synchronous grouting material, effectively enhancing the construction quality of the grouting material, and preventing the infiltration of water, thus avoiding the segregation and loss of the grouting material.
[0042] In areas with abundant groundwater, there is no need to take precipitation measures before shield tunneling construction, which avoids adding construction processes and equipment, shortens the construction period, reduces construction costs, and improves the sealing of the shield tunnel.
[0043] Reference Figure 3 As shown, it is a test picture of the grouting material in the prior art placed in water, which is easy to disperse underwater; Figure 4 As shown, it is a test picture of the grouting material in this embodiment placed in water, which achieves the effect of not dispersing underwater.
[0044] In the preparation step 1), the sand material is natural sand or machine-made sand, and the particle size of the sand material is not greater than 2 mm.
[0045] In the preparation step 1), the ratio of sand washing slurry to sand material is (1-5): (9-6) by mass.
[0046] In the preparation step 1), the silicate cement is of P·O42.5 grade, the fly ash is Class F fly ash of the second level, the activity grade of the mineral powder is not less than S95 grade, the gypsum is dihydrate gypsum, and the stone powder is building stone powder or natural stone powder.
[0047] In the preparation step 1), the cementitious material includes 10 to 30 parts of Portland cement, 30 to 50 parts of mineral powder, 10 to 20 parts of gypsum, 1 to 50 parts of fly ash and 1 to 10 parts of stone powder in proportion by weight.
[0048] In the preparation step 1), the proportion of the anti-dispersion agent and the retarder is (100-300):(1-4) by mass ratio.
[0049] In the preparation step 1), the anti-dispersion agent includes 8-10 parts of methyl cellulose, 1-4 parts of polyacrylamide, 50-70 parts of silica ash and 10-20 parts of polycarboxylic acid water reducing agent by mass ratio.
[0050] In the preparation step 1), the retarder is sucrose or sodium gluconate.
[0051] In the preparation step 2) of the embodiment, the upper part of the stirring cylinder 100 has a pneumatic stirring cavity 101, and the lower part of the stirring cylinder 100 has a rotating stirring cavity 103, and the rotating stirring cavity 103 is provided with a stirring shaft 104; the pneumatic stirring cavity 101 and the rotating stirring cavity 103 are provided with a partition plate 102, and the partition plate 102 is provided with through holes penetrating upward and downward; the inner side wall of the rotating stirring cavity 103 is provided with water spraying pipes 200, which are arranged along the circumferential direction of the rotating stirring cavity 103 and spirally arranged along the axial direction of the rotating stirring cavity 103.
[0052] In the preparation step 2), the water spraying pipes 200 spray water into the rotating stirring cavity 103 to form a plurality of water mist layers, and then the cementitious material, the aggregate and the additive are placed in the pneumatic stirring cavity 101, and a flowing high-pressure gas is injected into the pneumatic stirring cavity 101, and the high-pressure gas drives the cementitious material, the aggregate and the additive to be mixed by pneumatic stirring to form a mixture;
[0053] In the process of pneumatic stirring and mixing of the mixture in the pneumatic stirring cavity 101, the mixture falls into the rotating stirring cavity 103 through the plurality of through holes of the partition plate 102, passes through the plurality of water mist layers, and the water is injected into the mixture in multiple directions, and the stirring shaft 104 stirs and mixes the mixture and the water to form a grouting material.
[0054] The cementitious material, the aggregate and the additive are first mixed by pneumatic stirring in the pneumatic stirring cavity 101, which belongs to dry stirring and mixing, and in the process of mixing and forming the mixture, the mixture also falls into the rotating stirring cavity 103 through the through holes of the partition plate 102, and is first mixed with the plurality of water mist layers and then stirred and mixed with the water, which belongs to wet stirring and mixing.
[0055] In the process of forming the grouting material, the dry stirring and mixing is first performed, and then the wet stirring and mixing is performed, so that the stirring and mixing is more uniform and the phenomenon of clumping is avoided.
[0056] In the embodiment, the partition plate 102 is upwardly convex and tapered, the inner side wall of the pneumatic stirring cavity 101 is provided with air injection pipes, the air injection pipes are arranged along the axial direction of the pneumatic stirring cavity 101 and are arranged towards the partition plate 102;
[0057] In the step 2), after the cementing material, aggregate and additive are placed in the pneumatic mixing chamber 101 between the partition plate 102 and the inner side wall of the pneumatic mixing chamber 101, the jet pipe sprays the high-pressure gas in the form of inclined flow into the pneumatic mixing chamber 101, which drives the cementing material, aggregate and additive to rotate along the circumference of the pneumatic mixing chamber 101 and to be mixed in the process of rotation, forming the mixed material, which falls into the rotating mixing chamber 103 through the through hole in the process of rotation.
[0058] The partition plate 102 is in the form of convex cone, so that the mixed material can enter the rotating mixing chamber 103 through the through hole laterally in the process of mixing in the pneumatic mixing chamber 101, avoiding the mixed material falling vertically into the rotating mixing chamber 103, so that the mixed material can enter the rotating mixing chamber 103 through the through hole laterally in the process of mixing more uniformly.
[0059] In the embodiment, the grouting pressure of the grouting material is preferably 0.4-0.6 MPa when the grouting material is used for grouting.
[0060] After the grouting material is formed, the grouting material needs to be tested, and the following steps are adopted to obtain the test block of the grouting material:
[0061] 1), the cementing material is prepared by stirring;
[0062] 2), the sand and the washed sand mud are mixed by stirring;
[0063] 3), the cementing material, aggregate, additive and water are mixed by stirring to form the grouting material;
[0064] 4), the grouting material is continuously stirred and mixed, and the flow degree of the grouting material is tested over time, and the stirring time is 3 h, and the flow degree is tested every 1 h;
[0065] 5), the grouting material is placed in the test mold to test the setting time;
[0066] 6), the grouting material is poured into the test mold to test the compressive strength
[0067] The test block prepared according to the above steps is used to test the dispersion resistance of the test block. The test data obtained are as follows:
[0068] Table 1 Comparison of dispersion resistance of grouting material
[0069]
[0070] Table 2 Setting time and flow degree of grouting material
[0071]
[0072]
[0073] In the embodiment, the cementing material is prepared by premixing, and the stirred cementing material is pumped to a powder tank by a pump truck. A short screw is installed below the powder tank, one end of the short screw is connected to the powder tank, and the other end is connected to a first weighing hopper for weighing the cementing material. A mortar mixer is installed below the first weighing hopper, and a dust collector is installed on the upper layer of the mortar mixer to reduce dust.
[0074] A second weighing hopper is installed on the other side of the mortar mixer for weighing the addition amount of sand, and a flow meter is used to calculate the addition amount of washed sand and water. A material bin is installed below the mortar mixer, the material bin is connected to a grouting pump, and a filter screen is connected to the discharge port to filter large particles in the grouting material and ensure smooth pumping.
[0075] During the grouting process, the mixer needs to be started and stirred at all times. The stirred grouting material is injected into the pipe wall through the fixed pumping pipe of the grouting pump, and is used for post-grouting of the pipe wall of the subway shield.
[0076] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.
Claims
1. A method for preparing grouting material for anti-dispersion shield synchronous grouting, characterized in that: The method comprises the following preparation steps: 1) Provide cementitious material, aggregate, additive and water respectively, and the ratio of cementitious material, aggregate, additive and water is (20-40): (60-80): (0.1-0.5): (0.1-50) according to the mass ratio; The cementitious material is formed by mixing silicate cement, fly ash, mineral powder, gypsum and stone powder; the aggregate is formed by mixing sand and washed sand mud produced by shield construction; the additives include anti-dispersant and retarder; the anti-dispersant includes methyl cellulose, polyacrylamide, silica fume and polycarboxylic acid water reducer; 2) The cementitious material, aggregate and additive are sequentially added into a mixing drum for multi-directional stirring and mixing. During the stirring and mixing process, water is continuously injected into the mixing drum in multiple directions. The cementitious material, aggregate, additive and water are stirred and mixed to form grouting material used for anti-dispersion shield synchronous grouting.
2. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 1, characterized in that: In the preparation step 1), the sand material is natural sand or machine-made sand, and the particle size of the sand material is not greater than 2 mm; the sand washing mud is the mud produced by the shield sand washing line, the sand washing mud contains fine sand, and the mud specific gravity is not less than 1.
2.
3. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 1, characterized in that: In the preparation step 1), the ratio of the sand washing slurry to the sand material is (1-5): (9-6) by mass.
4. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 1, characterized in that: In the preparation step 1), the silicate cement is of P·O42.5 grade, the fly ash is secondary F class fly ash, the activity grade of the mineral powder is not less than S95 grade, the gypsum is dihydrate gypsum, and the stone powder is building stone powder or natural stone powder.
5. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 1, characterized in that: In the preparation step 1), the cementitious material includes, by weight, 10 to 30 parts of Portland cement, 30 to 50 parts of mineral powder, 10 to 20 parts of gypsum, 1 to 50 parts of fly ash, and 1 to 10 parts of stone powder.
6. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 1, characterized in that: In the preparation step 1), the ratio of the anti-dispersant to the retarder is (100-300): (1-4) by mass.
7. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 1, characterized in that: In the preparation step 1), the anti-dispersion agent includes 8 to 10 parts of methyl cellulose, 1 to 4 parts of polyacrylamide, 50 to 70 parts of silica fume, and 10 to 20 parts of polycarboxylic acid water reducer, based on weight proportion.
8. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 1, characterized in that: In the preparation step 1), the retarder is sucrose or sodium gluconate.
9. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to any one of claims 1 to 8, characterized in that: In the preparation step 2), the upper portion of the mixing drum has a pneumatic stirring chamber, the lower portion of the mixing drum has a rotating stirring chamber, and the rotating stirring chamber is provided with a stirring shaft; a partition plate is provided between the pneumatic stirring chamber and the rotating stirring chamber, and the partition plate is provided with a through hole extending vertically therethrough; a water spray pipe is provided on the inner side wall of the rotating stirring chamber, and the water spray pipe is arranged around the circumference of the rotating stirring chamber and spirally arranged along the axial direction of the rotating stirring chamber; In the preparation step 2), the water spray pipe sprays water into the rotating stirring chamber to form a multi-layer water mist layer, and then the cementitious material, aggregate, and additive are placed in a pneumatic stirring chamber. The pneumatic stirring chamber is injected with flowing high-pressure gas, and the high-pressure gas drives the cementitious material, aggregate, and additive to be pneumatically stirred and mixed to form a mixture; During the process of pneumatic stirring and mixing in the pneumatic stirring chamber, the mixture falls into the rotating stirring chamber through the multiple through holes of the partition plate. The mixture passes through multiple layers of water mist, and water is injected into the mixture from multiple directions. The stirring shaft stirs and mixes the mixture and the water to form the grouting material.
10. The method for preparing the grouting material for the anti-dispersion shield synchronous grouting according to claim 9, characterized in that: The partition plate is upwardly protruding in a conical shape, and an air jet is provided on the inner side wall of the pneumatic stirring chamber. The air jet is arranged along the axial direction of the pneumatic stirring chamber and toward the partition plate. In the preparation step 2), after the cementitious material, aggregate and additive are placed in the pneumatic stirring chamber, they are located between the partition plate and the inner wall of the pneumatic stirring chamber. The air jet sprays an oblique flow of high-pressure gas into the pneumatic stirring chamber. The high-pressure gas drives the cementitious material, aggregate and additive to rotate along the circumference of the pneumatic stirring chamber, and stirs and mixes them during the rotation to form the mixture. During the rotation, the mixture falls into the rotating stirring chamber through the through hole.