A curing agent for a raw shield muck subgrade material, a subgrade material, and a method for preparing the same

Abstract

The present application relates to a kind of solidified agent of original shield muck subgrade material, subgrade material and its preparation method, the solidified agent includes the following mass percentage of raw materials: alkali-activated cementitious material 60%-92%, stone powder 1%-12%, gypsum 5%-18% and additive 1%-10%; The solidified agent dosage accounts for the mass of the subgrade material 1%-15%; The present application also includes the preparation method of the shield muck solidified subgrade material, by mixing solidified agent and shield muck and stirring uniformly after paving, backfilling;The shield muck subgrade material of the present application, after curing, 3d strength exceeds 1.5MPa, 7d strength exceeds 3.0MPa, is more than 3 times of the same dosage cement curing strength.The solidified agent of the present application has low dosage, high curing strength, low curing cost, wide application scene, can be large-scale disposal and resource utilization shield muck.

Description

Technical Field

[0001] This invention belongs to the fields of building materials technology and solid waste treatment, specifically relating to a curing agent for undisturbed shield tunnel slag subgrade material, the subgrade material, and its preparation method. Background Technology

[0002] Currently, my country's urban rail transit construction is large-scale and rapid, generating a massive amount of tunnel boring machine (TBM) excavation waste. TBM excavation waste is generated during the excavation process to maintain the stability of the tunnel face. After the cutterhead cuts through the soil in front, it enters the soil chamber and is transported via screw conveyors, belt conveyors, rail-mounted waste trucks, or pumped to surface waste pits. During TBM tunneling, to prevent cutterhead wear and mud cake formation, and to ensure smooth tunneling and waste removal, bentonite, foaming agents, and polymers are added to improve the waste, giving it good fluidity.

[0003] Due to the high moisture and mud content of tunnel boring machine (TBM) excavation soil, open-air storage will cause a series of problems. Currently, in my country, TBM excavation soil is mainly disposed of as waste, resulting in high disposal costs and low resource utilization rates. Excavated material is transported to designated disposal sites by dump trucks. Therefore, how to dispose of the massive amounts of TBM excavation soil will be an unavoidable issue in subway construction.

[0004] Currently, my country's urbanization is still in a stage of rapid development, with ample room for infrastructure construction. If the undisturbed tunnel boring machine (TBM) excavation soil is used nearby for roadbed, base course, subbase course, foundation treatment, and other backfill materials, it will not only process and utilize TBM excavation soil on a large scale, but also reduce production costs, increase the added value of TBM excavation soil, and achieve "turning waste into treasure," resulting in significant economic, environmental, and social benefits. Summary of the Invention

[0005] This invention addresses the problem that shield tunneling excavation soil is difficult to dehydrate and screen, leading to difficulties in its disposal and resource utilization. It directly solidifies the undisturbed shield tunneling excavation soil to prepare roadbed materials, thereby increasing the added value of shield tunneling excavation soil.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A curing agent for undisturbed shield tunnel slag subgrade material, the curing agent comprising the following raw materials by mass percentage: 60%-92% alkali-activated cementitious material, 1%-12% stone powder, 5%-18% gypsum, and 1%-10% admixtures.

[0008] Preferably, the untreated and unscrewed tunnel boring machine (TBM) excavated soil is the soil that enters the soil chamber after the cutterhead of the TBM cuts the soil in front of it, and is then transported or pumped to the ground excavated soil pool by a screw conveyor, belt conveyor, or rail excavated soil car.

[0009] Preferably, the undisturbed excavated soil is one or more of earth pressure balance shield tunnel excavated soil or slurry balance shield tunnel excavated soil.

[0010] Preferably, the alkali-activated gelling material is composed of the following raw materials by mass percentage: 70%-95% gelling component and 5%-30% alkali activator.

[0011] Preferably, the cementing component is one or more of blast furnace slag, fly ash, silica fume, steel slag, and phosphorus slag.

[0012] Furthermore, the fineness of the gelling component is 200 mesh or higher.

[0013] Preferably, the alkaline activator is one or more of quicklime, sodium carbonate, sodium silicate, and sodium hydroxide.

[0014] Preferably, the quicklime has a calcium content greater than 75% and a fineness greater than 100 mesh.

[0015] Preferably, the sodium carbonate is in powder form with a fineness greater than 100 mesh.

[0016] Preferably, the sodium silicate is in powder form, with a modulus of 2.0-3.2 and a fineness greater than 100 mesh.

[0017] Preferably, the sodium hydroxide is in solid flake form, analytical grade, with a purity greater than 99%.

[0018] Preferably, the stone powder is one or more of natural stone powder and recycled construction waste powder, with a fineness of 200 mesh or higher.

[0019] Preferably, the gypsum is one or more of natural gypsum, desulfurized gypsum, and phosphogypsum.

[0020] Preferably, the additive is one or more of sodium aluminate, sodium sulfate, aluminum sulfate, and polyaluminum chloride.

[0021] Preferably, the sodium aluminate is in powder form with a fineness greater than 100 mesh.

[0022] Preferably, the sodium sulfate is in powder form with a fineness greater than 100 mesh.

[0023] Preferably, the aluminum sulfate is in the form of solid granules.

[0024] Preferably, the polyaluminum chloride (PAC) is in the form of a solid powder.

[0025] The present invention also provides a undisturbed shield tunneling excavation soil roadbed material, which includes undisturbed shield tunneling excavation soil and the curing agent described in any of the above embodiments; the mass of the curing agent is 1-15% of the mass of the undisturbed shield tunneling excavation soil.

[0026] The present invention also provides a method for preparing the above-mentioned undisturbed shield tunneling spoil roadbed material, comprising the following steps:

[0027] (1) Based on the design mix ratio of the earthwork paving thickness, spread the curing agent evenly on the surface of the original shield tunnel slag to be treated;

[0028] (2) Use an excavator to mix to ensure that the curing agent and the original shield tunneling slag are initially mixed evenly to obtain mixture S1;

[0029] (3) Use a crushing and screening bucket to crush and screen the material S1 evenly to obtain the mixture S2;

[0030] (4) Use a paver to loosely spread the mixture S2, and then use a bucket to compact and level it; for materials with relatively low moisture content, a road roller can be used to compact them.

[0031] The original shield tunneling spoil roadbed material of the present invention can be used as a base course, subbase course, foundation, slope, retaining wall and backfill material in different scenarios.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] This invention, based on alkali-activated cementitious materials, stone powder, and gypsum, further enhances the solidification strength by introducing admixtures. Typically, after shield tunneling slag and solidification materials are mixed, the alkaline activators in the alkali-activated cementitious materials, such as quicklime, sodium carbonate, sodium silicate, and sodium hydroxide, dissolve in the undisturbed shield tunneling slag, creating a strongly alkaline environment. Under the influence of this strong alkali, the Si-O and Al-O bonds in the glassy structure of the cementing components (blast furnace slag, fly ash, silica fume, steel slag, phosphorus slag, etc.) break, releasing [SiO4] and [AlO4] tetrahedra that diffuse outwards and adsorb onto the surface of the slag particles, undergoing a condensation reaction to generate hydrated calcium silicate, hydrated calcium aluminate, and hydrated calcium aluminosilicate gels, forming a solidified slag body. Stone powder acts as a skeleton or filler, and gypsum can absorb some free water. However, when the dosage of the alkali-activated cementitious material is low, the alkali concentration in the mixture system also decreases, and the alkali activation reaction is correspondingly weakened, macroscopically manifesting as a reduction in cementing material, thus leading to a decrease in strength. This invention releases AlO2 after dissolving in water by adding additives such as sodium aluminate, sodium sulfate, aluminum sulfate, and polyaluminum chloride. - SO4 2- Al 3+ Plasma further hydrates and releases hydroxide ions, which enhance the alkali-activated reaction in the slag system and react with the active clay minerals in the original shield tunnel slag. The plasma aggregates between the slag particles and gradually envelops the surrounding slag body, achieving the effects of adsorption, coagulation and solidification, thereby improving the solidification strength.

[0034] This invention addresses the need for low-strength shield tunnel slag solidification materials, specifically when the dosage and concentration of alkali-activated cementitious materials are low. It enhances the alkali-activated reaction by adding a certain amount of additives to improve the solidification strength.

[0035] When the curing agent of this invention is applied to undisturbed shield tunnel excavation soil subgrade material, the 3-day compressive strength exceeds 1.5 MPa, and the 7-day compressive strength exceeds 3.0 MPa. Compared with no admixture, the strength of the undisturbed shield tunnel excavation soil subgrade material is increased by more than 100%. At the same dosage, the cured strength is more than 3 times that of cement, and the advantage is more obvious with a lower dosage. This invention has outstanding advantages such as low dosage, short curing time, high curing strength, and low curing cost, and has broad application prospects. Attached Figure Description

[0036] Figure 1 This is a schematic diagram illustrating the preparation process of the original shield tunneling slag subgrade material of the present invention;

[0037] Figure 2 This is a comparison diagram of the curing strength of specific embodiment 1 of the present invention, comparative example 1, and cement. Detailed Implementation

[0038] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0039] This invention provides a curing agent for undisturbed shield tunnel slag subgrade material, the curing agent comprising the following raw materials by mass percentage: 60%-92% alkali-activated cementitious material, 1%-12% stone powder, 5%-18% gypsum, and 1%-10% admixtures.

[0040] The alkali-activated gelling material is composed of the following raw materials by mass percentage: 70%-95% gelling component and 5%-30% alkali activator.

[0041] The cementing components in the alkali-activated cementitious material are one or more of blast furnace slag, fly ash, silica fume, steel slag, and phosphorus slag.

[0042] The fineness of the gelling component is 200 mesh or higher.

[0043] The alkali activator in the alkali-activated cementitious material is one or more of quicklime, sodium carbonate, sodium silicate, and sodium hydroxide.

[0044] The quicklime has a calcium content greater than 75% and a fineness greater than 100 mesh.

[0045] The sodium carbonate is in powder form with a fineness greater than 100 mesh.

[0046] The sodium silicate is in powder form, with a modulus of 2.0-3.2 and a fineness greater than 100 mesh.

[0047] The sodium hydroxide is in solid flake form, analytical grade, with a purity greater than 99%.

[0048] The stone powder is one or more of natural stone powder and recycled construction waste powder, with a fineness of 200 mesh or higher.

[0049] The gypsum is one or more of natural gypsum, desulfurized gypsum, and phosphogypsum.

[0050] The additive is one or more of sodium aluminate, sodium sulfate, aluminum sulfate, and polyaluminum chloride.

[0051] The sodium aluminate is in powder form with a fineness greater than 100 mesh.

[0052] The sodium sulfate is in powder form with a fineness greater than 100 mesh.

[0053] The aluminum sulfate is in solid granular form.

[0054] The polyaluminum chloride (PAC) is in the form of a solid powder.

[0055] The present invention also provides a undisturbed shield tunneling spoil roadbed material, comprising undisturbed shield tunneling spoil and the aforementioned curing agent, wherein the mass of the curing agent is 1%-15% of the mass of the undisturbed shield tunneling spoil.

[0056] The untreated and unscrewed tunnel boring machine (TBM) excavated soil refers to the soil that enters the soil chamber after the cutterhead of the TBM cuts the soil in front of it, and is then transported or pumped to the ground excavated soil pool by screw conveyor, belt conveyor, rail excavated soil car.

[0057] The original slag is one or more of earth pressure balance shield tunnel slag or slurry balance shield tunnel slag.

[0058] Preferably, the moisture content of the undisturbed shield tunneling excavated soil is 30%-50%, and the mud content is above 70%. The preparation method of the undisturbed shield tunneling excavated soil subgrade material includes the following steps:

[0059] (1) Based on the design mix ratio of the earthwork paving thickness, spread the curing agent evenly on the surface of the shield tunnel slag to be treated;

[0060] (2) Use an excavator to mix to ensure that the curing agent and the shield tunneling excavation are initially and evenly mixed to obtain mixture S1;

[0061] (3) Use a crushing and screening bucket to crush and screen the material S1 evenly to obtain the mixture S2;

[0062] (4) Use a paver to loosely spread the mixture S2, and then use a bucket to compact and level it; for materials with relatively low moisture content, a road roller can be used to compact them.

[0063] In the specific implementation process, a test section was constructed on the original shield tunnel slag subgrade material to determine the mixing ratio of the curing agent and obtain the optimal construction process parameters.

[0064] Loose paving should be carried out using a combination of bulldozers and manual labor. After loose paving is completed, a vibratory roller should be used for static compaction, followed by initial leveling with a grader.

[0065] After initial leveling, a vibratory roller is used to compact the solidified slag mixture at the optimum moisture content (±2%). Before the compaction is completed, a grader should be used for a final shaping.

[0066] After the concrete mixture of tunnel boring machine excavation material is compacted, water should be sprayed on its surface immediately and then covered with a film for curing.

[0067] The quality of the formed roadbed is inspected and accepted.

[0068] The compaction degree, deflection value, and differential settlement of the original shield tunnel excavation soil subgrade material should meet the design requirements of the specifications; otherwise, reconstruction should be carried out.

[0069] The application of the original shield tunneling slag subgrade material of the present invention includes, but is not limited to, its use as a solidified subgrade material, base course, subbase course, foundation, slope, retaining wall, and backfill material in different scenarios.

[0070] The following detailed description includes further examples. The undisturbed shield tunneling excavated soil in the following examples and comparative examples was taken from the completely weathered slate shield tunneling excavated soil of the northern extension of Changsha Metro Line 1. The tested moisture content was 41%, and the mud content was 90%. The quicklime, sodium carbonate, and sodium silicate used were 100 mesh, and the sodium silicate powder modulus was 2.85; the sodium hydroxide was a solid, flaky, analytically pure powder with a purity greater than 99%; the sodium aluminate, sodium sulfate, and polyaluminum chloride used were 100 mesh, and the aluminum sulfate was a solid granular powder.

[0071] Example 1

[0072] A curing agent for undisturbed shield tunnel slag subgrade material is composed of the following raw materials in the indicated mass percentages: blast furnace slag 45.97%, fly ash 15.28%, desulfurized gypsum 8.32%, stone powder 8.15%, quicklime 6.61%, sodium carbonate 6.23%, sodium silicate 4.79%, and sodium aluminate 4.65%.

[0073] The curing agent was used to prepare undisturbed shield tunnel spoil roadbed material, with an admixture dosage of 12% in the undisturbed shield tunnel spoil. Figure 1 As shown, the preparation method of roadbed material includes the following steps:

[0074] (1) Based on the design mix ratio of the earthwork paving thickness, spread the curing agent evenly on the surface of the original shield tunnel slag to be treated;

[0075] (2) Use an excavator to mix to ensure that the curing agent and the original shield tunneling slag are initially mixed evenly to obtain mixture S1;

[0076] (3) Use a crushing and screening bucket to crush and screen the material S1 evenly to obtain the mixture S2;

[0077] (4) Use a paver to loosely spread the mixture S2, then use a bucket to compact and level it, and cover it with a film for curing.

[0078] After testing, such as Figure 2 As shown, the undisturbed shield tunnel slag solidified subgrade material prepared in Example 1 has an average compressive strength of 2.62 MPa at 3 days and an average compressive strength of 3.91 MPa at 7 days.

[0079] Comparative Example 1

[0080] A curing agent for undisturbed shield tunnel slag roadbed material is composed of the following raw materials by mass percentage: blast furnace slag, fly ash, desulfurized gypsum, stone powder, quicklime, sodium carbonate, and sodium silicate, and the proportions between the components are the same as in Example 1.

[0081] The curing agent was used to prepare undisturbed shield tunnel slag roadbed material. The amount of the curing agent in the undisturbed shield tunnel slag was 12%, and the preparation method of the cured roadbed material was the same as in Example 1.

[0082] After testing, such as Figure 2 As shown, the undisturbed shield tunnel slag subgrade material prepared in Comparative Example 1 has an average compressive strength of 0.85 MPa at 3 days and an average compressive strength of 1.61 MPa at 7 days.

[0083] Example 2

[0084] A curing agent for undisturbed shield tunnel slag subgrade material is composed of the following raw materials by mass percentage: blast furnace slag 52.36%, silica fume 5.35%, natural gypsum 9.16%, stone powder 7.63%, quicklime 6.95%, sodium carbonate 7.12%, sodium silicate 5.18%, sodium aluminate 1.48%, and sodium sulfate 4.77%.

[0085] The curing agent was used to prepare undisturbed shield tunnel spoil roadbed material, with an admixture dosage of 10% in the undisturbed shield tunnel spoil. Figure 1 As shown, the preparation method of roadbed material includes the following steps:

[0086] (1) Based on the design mix ratio of the earthwork paving thickness, spread the curing agent evenly on the surface of the original shield tunnel slag to be treated;

[0087] (2) Use an excavator to mix to ensure that the curing agent and the original shield tunneling slag are initially mixed evenly to obtain mixture S1;

[0088] (3) Use a crushing and screening bucket to crush and screen the material S1 evenly to obtain the mixture S2;

[0089] (4) Use a paver to loosely spread the mixture S2, then use a bucket to compact and level it, and cover it with a film for curing.

[0090] According to the test, the undisturbed shield tunnel slag solidified subgrade material prepared in Example 2 has an average compressive strength of 2.12 MPa at 3 days and an average compressive strength of 3.30 MPa at 7 days.

[0091] Comparative Example 2

[0092] A curing agent for undisturbed shield tunnel slag subgrade material, serving as a comparative example of Example 2, is provided. It comprises the following raw materials by mass percentage: blast furnace slag, silica fume, natural gypsum, stone powder, quicklime, sodium carbonate, and sodium silicate, with the proportions of each component being the same as in Example 2.

[0093] The curing agent is added at a rate of 10% to the original shield tunnel slag, and the preparation method of the cured roadbed material is the same as in Example 2.

[0094] Tests showed that the undisturbed shield tunnel slag subgrade material prepared in Comparative Example 2 had an average compressive strength of 0.67 MPa at 3 days and an average compressive strength of 1.25 MPa at 7 days.

[0095] Example 3

[0096] A curing agent for undisturbed shield tunnel slag subgrade material is composed of the following raw materials by mass percentage: blast furnace slag 60.79%, natural gypsum 11.12%, stone powder 6.63%, quicklime 6.59%, sodium carbonate 6.44%, sodium silicate 4.35%, and aluminum sulfate 4.08%.

[0097] The curing agent was used to prepare undisturbed shield tunnel spoil roadbed material, with an admixture dosage of 10% in the undisturbed shield tunnel spoil. Figure 1 As shown, the preparation method of roadbed material includes the following steps:

[0098] (1) Based on the design mix ratio of the earthwork paving thickness, spread the curing agent evenly on the surface of the original shield tunnel slag to be treated;

[0099] (2) Use an excavator to mix to ensure that the curing agent and the original shield tunneling slag are initially mixed evenly to obtain mixture S1;

[0100] (3) Use a crushing and screening bucket to crush and screen the material S1 evenly to obtain the mixture S2;

[0101] (4) Use a paver to loosely spread the mixture S2, then use a bucket to compact and level it, and cover it with a film for curing.

[0102] Tests showed that the undisturbed shield tunnel slag solidified subgrade material prepared in Example 3 had an average compressive strength of 1.90 MPa at 3 days and an average compressive strength of 3.08 MPa at 7 days.

[0103] Example 4

[0104] A curing agent for undisturbed shield tunnel slag subgrade material is composed of the following raw materials by mass percentage: blast furnace slag 67.41%, natural gypsum 8.59%, construction waste powder 5.33%, quicklime 5.45%, sodium carbonate 5.15%, sodium silicate 3.64%, sodium hydroxide 1.18%, and polyaluminum chloride 3.25%.

[0105] The curing agent was used to prepare undisturbed shield tunnel spoil roadbed material, with an admixture dosage of 8% in the undisturbed shield tunnel spoil. Figure 1 As shown, the preparation method of roadbed material includes the following steps:

[0106] (1) Based on the design mix ratio of the earthwork paving thickness, spread the curing agent evenly on the surface of the shield tunnel slag to be treated;

[0107] (2) Use an excavator to mix to ensure that the curing agent and the original shield tunneling slag are initially mixed evenly to obtain mixture S1;

[0108] (3) Use a crushing and screening bucket to crush and screen the material S1 evenly to obtain the mixture S2;

[0109] (4) Use a paver to loosely spread the mixture S2, then use a bucket to compact and level it, and cover it with a film for curing.

[0110] Tests showed that the undisturbed shield tunnel slag subgrade material prepared in Example 4 had an average compressive strength of 1.67 MPa after 3 days and an average compressive strength of 3.19 MPa after 7 days.

[0111] Comparative Example 3

[0112] A curing agent for undisturbed shield tunneling spoil roadbed material is provided as a comparative example of Examples 1-4. Silicate cement is used as the curing agent, with cement content in the undisturbed shield tunneling spoil at 8%, 10%, and 12%, respectively. The preparation method of the roadbed material is the same as in Examples 1-4.

[0113] Tests showed that the undisturbed shield tunnel slag-solidified subgrade material prepared in Comparative Example 3 had an average compressive strength of 0.35 MPa at 3 days and 0.58 MPa at 7 days when the cement content was 8%; an average compressive strength of 0.43 MPa at 3 days and 0.84 MPa at 7 days when the cement content was 10%; and a cement content of 12%... Figure 2 As shown, the average compressive strength at 3 days is 0.57 MPa, and the average compressive strength at 7 days is 1.08 MPa.

[0114] Figure 2 This is a comparison chart of the curing strength of cement in Example 1 and Comparative Example 1 of the present invention. Figure 2 It can be seen that, with an admixture dosage of 12%, the 3-day compressive strength of Example 1 is 3.08 times that of Comparative Example 1 and 4.60 times that of cement; the 7-day compressive strength of Example 1 is 2.43 times that of Comparative Example 1 and 3.62 times that of cement. Therefore, compared with no admixture, the strength of the undisturbed shield tunnel slag solidified subgrade material is increased by more than 100%; at the same admixture dosage, the solidification strength is more than 3 times that of cement, and the advantage is more pronounced at shorter curing times.

[0115] Furthermore, the results of Examples 1 and 2 and Comparative Examples 1 and 2 show that by adding admixtures, the strength of the original shield tunnel slag subgrade material of the present invention is increased by more than 100%, which is a significant effect.

[0116] As can be seen from the results of Examples 1-4 and Comparative Example 3, the curing strength of the original shield tunnel slag solidified roadbed material provided by the present invention is more than 3 times that of the curing strength of cement with the same dosage, and the effect is better with less dosage.

[0117] In addition, the present invention has the following other beneficial effects:

[0118] (1) No need to dewater or screen the original shield tunneling slag. The disposal process is simple and low-cost, which greatly improves the added value of shield tunneling slag.

[0119] (2) For different types of original shield tunneling slag, the mix ratio can be adjusted to meet the corresponding solidification strength requirements, and the application range is wide.

[0120] (3) It can dispose of and utilize shield tunneling excavated soil on a large scale, save shield tunneling excavated soil transportation and disposal costs, reduce construction costs, avoid safety risks and hidden dangers caused by excavated soil storage, and obtain good economic, environmental and social benefits.

[0121] It should be noted that the original shield tunneling slag used in the above embodiments has a high degree of weathering, high clay content, low coarse particle content, and is difficult to dispose of. The performance of the shield tunneling slag solidified roadbed material made from it is not optimal. If the solidified roadbed material prepared from shield tunneling slag with higher sand and gravel content or lower moisture content has better compressive strength than the present invention, it should be within the scope of the present invention.

[0122] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; however, any combination of these technical features that does not contradict each other should be considered within the scope of this specification.

Claims

1. A type of undisturbed shield tunneling spoil roadbed material, characterized in that, Its raw materials include undisturbed shield tunneling excavation soil and a solidifying agent, wherein the mass of the solidifying agent is 1%-15% of the mass of the undisturbed shield tunneling excavation soil; the solidifying agent comprises the following raw materials by mass percentage: 60%-92% alkali-activated cementitious material, 1%-12% stone powder, 5%-18% gypsum, and 1%-10% admixtures; The alkali-activated gelling material is composed of the following raw materials by mass percentage: 70%-95% gelling component and 5%-30% alkali activator; The cementing component is one or more of blast furnace slag, fly ash, silica fume, steel slag, and phosphorus slag. The stone powder is one or more of natural stone powder and recycled construction waste powder. The gypsum is one or more of natural gypsum, desulfurized gypsum, and phosphogypsum; The additive is one or more of sodium aluminate, sodium sulfate, aluminum sulfate, and polyaluminum chloride; The undisturbed shield tunneling excavated soil refers to the untreated excavated soil that enters the soil chamber after the cutterhead of the shield machine cuts the soil in front of it, and is transported or pumped to the ground excavated soil pool by screw conveyor, belt conveyor, rail excavated soil car. The moisture content of the undisturbed shield tunneling excavated soil is 30%-50%, and the mud content is above 70%.

2. The original shield tunneling spoil roadbed material according to claim 1, characterized in that, The alkaline activator is one or more of quicklime, sodium carbonate, sodium silicate, and sodium hydroxide.

3. The method for preparing undisturbed shield tunneling spoil roadbed material according to any one of claims 1-2, characterized in that, Includes the following steps: (1) Based on the design mix ratio of the earthwork paving thickness, spread the curing agent evenly on the surface of the original shield tunnel slag to be treated; (2) Use an excavator to mix to ensure that the curing agent and the original shield tunneling slag are initially mixed evenly to obtain mixture S1; (3) The material S1 is crushed and screened evenly using a crushing and screening bucket to obtain a mixture S2; (4) Use a paver to loosely spread the mixture S2, and then use a bucket to compact and level it; for materials with relatively low moisture content, a road roller can be used to compact them.

4. The application of the original shield tunnel slag subgrade material as described in claim 3 as a base course, subbase course, foundation, slope, retaining wall, and backfill material.

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