Solid waste-based cementing material synergistic fiber solidified soil and preparation method thereof

Abstract

The invention relates to solid-waste-based cementing material synergistic fiber solidified soil and a preparation method thereof. The solid-waste-based cementing material synergistic fiber solidified soil is prepared from wet soil, a solid-waste-based cementing material, sisal fibers, water and anhydrous sodium sulfate, the moisture content of the wet soil is the optimal moisture content of the soil; the mass mixing amounts of the solid waste-based cementing material, the sisal fiber, the water and the anhydrous sodium sulfate are respectively 10%, 0.6%, 4.5% and 0.3% of the dry soil; the preparation method comprises the following steps: drying, crushing and screening the undisturbed soil; wet soil is prepared according to the optimal water content; cleaning the sisal fibers, naturally drying the sisal fibers to constant weight, and then immersing the sisal fibers in a NaOH solution; wrapping the sisal fibers with a solid waste-based cementing material; sequentially adding the sisal fibers, the solid waste-based cementing material and the anhydrous sodium sulfate into the wet soil, and mixing; weighing water and adding the water into the mixture to obtain a mixture; according to the technical scheme, the overall mechanical property of the solidified soil can be remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bulk solid waste utilization, and in particular to a solid waste-based gelling material synergistically fiber-solidified soil and a preparation method thereof. Background Art

[0002] Solidified soil is made by mixing soil and cementitious materials in a certain proportion and then chemically modifying them. With significant advantages such as low cost and convenient construction, solidified soil materials have been widely used in engineering fields such as roadbed filling, foundation reinforcement, and channel anti-seepage lining. At present, traditional materials such as cement and lime are still the main choices for cementitious materials. However, these materials are accompanied by significant carbon emissions during the production process, and their negative environmental impact is contrary to the concept of sustainable development. Against the backdrop of increasingly prominent global ecological and environmental problems, environmental protection and resource recycling have become a social consensus. Therefore, the development of soil solidification technology that meets the requirements of green and low-carbon development has become a research hotspot in the current field of geotechnical engineering.

[0003] Fly ash, a byproduct of coal-fired boilers in thermal power plants, accounts for a large proportion of industrial solid waste emissions and has high pozzolanic activity, with its chemical composition mainly composed of active SiO2 and Al2O3. In addition, carbide slag, a highly alkaline waste residue produced by the hydrolysis of calcium carbide during the acetylene production process, has a main component of Ca(OH)2. This substance can provide an alkaline environment for active pozzolanic materials such as fly ash and slag, promoting pozzolanic reactions. Based on the synergistic solidification mechanism of carbide slag and fly ash, many new soil solidification materials have been developed. However, in actual engineering applications, carbide slag-fly ash-based solidified soil materials are prone to surface cracking and poor deformation resistance. This not only significantly weakens the mechanical properties of the material, but also affects its engineering durability, thus seriously restricting the promotion and application of such solidified materials. Considering that fibers have a significant anti-crack strengthening effect in soil improvement, the introduction of fibers into the solidified soil system can effectively inhibit the initiation and propagation of cracks and improve the system's deformation resistance.

[0004] Patent CN202311855794.5 discloses a method for preparing a silt soil solidifier based on the synergistic effect of carbide slag, desulfurized gypsum, and glass fiber. In this technology, glass fiber relies on its inherent physical properties (tensile strength and interfacial friction effect) to achieve crack suppression.

[0005] Patent CN119241187A proposes a soft soil improvement system using industrial waste residue combined with a water glass-based alkali activator and incorporating palm fiber. This technology relies on palm fiber to form a three-dimensional network within the soil, enhancing the soil's mechanical properties through interfacial friction. This patent utilizes a fiber reinforcement technology similar to that of patent CN202311855794.5, focusing on improving soil mechanical properties through fiber reinforcement.

[0006] In summary, current technologies primarily leverage the reinforcing effect of fibers and the gelling effect of solid waste-based cementitious materials to improve soil performance. Because fibers in solidified soil systems typically fail by being pulled out rather than broken, enhancing the interfacial adhesion between the fibers and the solidified soil matrix is ​​a key challenge limiting the full potential of fiber reinforcement. Furthermore, solid waste-based cementitious materials require activators to fully activate their activity. Therefore, enhancing the interfacial adhesion between the fibers and the solidified soil matrix while simultaneously enhancing the activity of solid waste-based cementitious materials remains a key challenge that needs to be addressed. Summary of the Invention

[0007] In response to the existing technology, the present invention innovatively proposes a solid waste-based cementitious material and fiber-solidified soil and its preparation method. By compounding industrial solid wastes such as calcium carbide slag and fly ash with anhydrous sodium sulfate and adding a certain proportion of sisal fiber, the mechanical properties of the solidified soil can be significantly improved. In particular, by utilizing this method, it is possible to optimize the addition sequence and control the proportion of each component to achieve the purpose of enhancing the interfacial bonding force between the fiber and the solidified soil matrix while enhancing the activity of the solid waste-based cementitious material. The present invention has the characteristics of simple method and easy operation.

[0008] In order to achieve the above object, the technical solution of the present invention is achieved as follows:

[0009] In one aspect, the present invention provides a solid waste-based cementitious material and fiber-solidified soil, comprising wet soil, solid waste-based cementitious material, sisal fiber, water and anhydrous sodium sulfate.

[0010] Furthermore, the wet soil is made by mixing dry soil and water, and the moisture content of the wet soil is the optimal moisture content of soil.

[0011] Furthermore, the mass content of the solid waste-based cementitious material, sisal fiber, water and anhydrous sodium sulfate is 10%, 0.6%, 4.5% and 0.3% of the dry soil respectively.

[0012] Furthermore, the solid waste-based cementitious material includes the following raw materials in percentage by mass: 1%-5% of dry soil mass of carbide slag and 5%-9% of dry soil mass of fly ash.

[0013] Furthermore, the solid waste-based cementitious material includes the following raw materials in percentage by mass: 3% of dry soil mass of carbide slag and 7% of dry soil mass of fly ash.

[0014] Alternatively, the solid waste-based cementitious material includes the following raw materials in percentage by mass: 5% of dry soil mass of carbide slag and 5% of dry soil mass of fly ash.

[0015] Alternatively, the solid waste-based cementitious material includes the following raw materials in percentage by mass: 4% of dry soil mass of carbide slag and 6% of dry soil mass of fly ash.

[0016] Furthermore, the sisal fiber has a length of 11 mm.

[0017] In addition, the present invention also provides a method for preparing the above-mentioned solid waste-based cementitious material and fiber-solidified soil, comprising the following steps:

[0018] Step 1: Dry the original soil, crush it, and screen it to obtain dry soil, and then determine the optimal moisture content of the soil.

[0019] Step 2: Add the water required for dry soil according to the optimal moisture content, stir evenly to make wet soil, seal it and let it stand for more than 24 hours;

[0020] Step 3: Use deionized water to wash the sisal fiber to remove impurities on its surface, then place it in a ventilated environment to dry naturally to constant weight, and completely immerse the treated sisal fiber in a pre-prepared NaOH solution with a concentration of 6% by mass for 12 hours before taking it out for use;

[0021] Step 4: Weigh 4% of the dry soil mass of calcium carbide slag and 6% of the dry soil mass of fly ash, mix them evenly and prepare a solid waste-based cementitious material;

[0022] Step 5: Use the solid waste-based gelling material from step 4 to fully and evenly wrap the sisal fibers from step 3;

[0023] Step 6: Weigh 0.3% of the mass of dry soil with anhydrous sodium sulfate, and add the sisal fiber, solid waste-based cementitious material, and anhydrous sodium sulfate obtained in step 5 to the wet soil in sequence and mix evenly;

[0024] Step 7: Weigh 4.5% of the dry soil mass of water and add it to the mixture prepared in step 6, and stir thoroughly to obtain a solid waste-based cementitious material and fiber-solidified soil mixture.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention proposes a solid waste-based cementitious material synergistically combined with fiber-solidified soil and a preparation method thereof, characterized by pre-treating sisal fibers with a NaOH solution to synergistically enhance the properties of the solidified soil through the following four mechanisms: First, after being soaked in a NaOH solution, the sisal fibers can be etched to form a multi-scale rough interface, which creates a mechanical interlocking effect between the sisal fibers and the solidified soil particles. The enhanced interfacial friction energy dissipation mechanism helps to increase the interfacial friction between the two, significantly enhancing the deformation resistance of the fiber-solidified soil. Second, after the NaOH solution-pretreated sisal fibers are uniformly coated with the solid waste-based cementitious material, as the hydration reaction within the soil continues, a large amount of dense hydration product layer gradually forms on the surface of the sisal fibers. This structural feature significantly enhances the bond strength of the sisal fibers in the transition zone between the sisal fibers and the solidified soil matrix. Third, after being pre-treated with a NaOH solution, the sisal fibers can weaken the bonding force between hemicellulose and cellulose, causing the chemical bonds between hemicellulose and lignin molecules to break, thereby destroying the lignin and degrading the hemicellulose, greatly improving the high water absorption of the sisal fibers and reducing the occurrence of sisal fiber agglomeration. At the same time, it enhances the interfacial compatibility between the sisal fiber and the solidified soil matrix. Fourthly, the NaOH solution pretreatment creates a stable alkaline microenvironment on the sisal fiber surface, providing favorable alkaline conditions for the hydration of the cementitious material during the curing process. This assists the activator in accelerating the hydration reaction, thereby promoting the formation of more hydration products and ultimately significantly improving the overall mechanical properties of the solidified soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a flow chart of a method for preparing solid waste-based cementitious materials and fiber-solidified soil according to the present invention;

[0028] Figure 2 is a flow chart of Example 1, Example 2, and Example 3;

[0029] Figure 3 is a flow chart of Example 4;

[0030] Figure 4 is a flow chart of Example 5;

[0031] Figure 5 is a flow chart of Example 6;

[0032] Figure 6 is a flow chart of Example 7;

[0033] Figure 7 is a flow chart of Example 8;

[0034] Figure 8 It is the unconfined compressive strength diagram of the stabilized soil samples obtained by different preparation methods. DETAILED DESCRIPTION

[0035] To make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the following will further describe the present invention in detail with reference to the accompanying drawings and specific embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] Example 1: A solid waste-based cementitious material solidifies soil. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil, and the optimal moisture content of the soil is measured (18%); the solid waste-based cementitious material is added in an amount of 10% of the dry soil mass, and the carbide slag-fly ash system in the solid waste-based cementitious material is 3% of the dry soil mass of carbide slag and 7% of the dry soil mass of fly ash; the anhydrous sodium sulfate content is 0.3% of the dry soil mass.

[0037] Step 1: Add the water required for dry soil according to the optimal moisture content, stir evenly to make wet soil, and then seal and let it stand for more than 24 hours;

[0038] Step 2: Weigh the required mass of solid waste-based cementitious material and anhydrous sodium sulfate respectively, add the solid waste-based cementitious material and anhydrous sodium sulfate to the wet soil in sequence and mix evenly;

[0039] Step 3: Weigh 4.5% of the dry soil mass of water and add it to the mixture prepared in Step 2. Stir thoroughly to obtain a solid waste-based cementitious material-solidified soil mixture. The mixture is then loaded into a cylindrical mold with an inner diameter of 39.1 mm and a height of 80 mm in three batches. After static compaction and demolding, the solidified soil specimens are obtained. Finally, the demolded specimens are wrapped and placed in a standard curing box for curing for 7 days. After removal, an unconfined compressive strength test is performed to determine the unconfined compressive strength of the solidified soil specimens.

[0040] Example 2: A solid waste-based cementitious material solidifies soil. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil, and the optimal moisture content of the soil is measured (18%); the solid waste-based cementitious material is added in an amount of 10% of the dry soil mass, and the carbide slag-fly ash system in the solid waste-based cementitious material is 5% of the dry soil mass of carbide slag and 5% of the dry soil mass of fly ash; the anhydrous sodium sulfate content is 0.3% of the dry soil mass.

[0041] The preparation method of the solid waste-based cementitious material solidified soil in this embodiment is the same as that in Example 1.

[0042] Example 3: A solid waste-based cementitious material solidifies soil. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil, and the optimal moisture content of the soil is measured (18%); the solid waste-based cementitious material is added in an amount of 10% of the dry soil mass, and the carbide slag-fly ash system in the solid waste-based cementitious material is 4% of the dry soil mass of carbide slag and 6% of the dry soil mass of fly ash; the anhydrous sodium sulfate content is 0.3% of the dry soil mass.

[0043] The preparation method of the solid waste-based cementitious material solidified soil in this embodiment is the same as that in Example 1.

[0044] Example 4:

[0045] A solid waste-based cementitious material is used to solidify soil using fibers. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil. The optimal moisture content of the soil (18%) is measured. The solid waste-based cementitious material is added in an amount of 10% of the dry soil mass. The carbide slag-fly ash system in the solid waste-based cementitious material is 4% of the dry soil mass of carbide slag and 6% of the dry soil mass of fly ash. The anhydrous sodium sulfate content is 0.3% of the dry soil mass. The sisal fiber length is 11mm, and the sisal fiber content is 0.6% of the dry soil mass.

[0046] Step 1: Add the water required for dry soil according to the optimal moisture content, stir evenly to make wet soil, and then seal and let it stand for more than 24 hours;

[0047] Step 2: Weigh the required mass of sisal fiber, solid waste-based gelling material and anhydrous sodium sulfate respectively, first fully and evenly wrap the sisal fiber with the solid waste-based gelling material, then add the sisal fiber, solid waste-based gelling material and anhydrous sodium sulfate to the wet soil in sequence and mix evenly;

[0048] Step 3: Weigh 4.5% of the dry soil mass in water and add it to the mixture prepared in Step 2. Stir thoroughly to obtain a solid waste-based cementitious material-fiber-solidified soil mixture. The mixture is then loaded into a cylindrical mold with an inner diameter of 39.1 mm and a height of 80 mm in three batches. After static compaction and demolding, the molds are removed to produce the solidified soil samples. Finally, the demolded samples are wrapped and placed in a standard curing chamber for curing for 7 days. The samples are then removed and subjected to unconfined compressive strength tests to determine the unconfined compressive strength of the solid waste-based cementitious material-fiber-solidified soil samples.

[0049] Example 5:

[0050] A solid waste-based cementitious material is used to solidify soil using fibers. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil. The optimal moisture content of the soil (18%) is measured. The solid waste-based cementitious material is added in an amount of 10% of the dry soil mass. The carbide slag-fly ash system in the solid waste-based cementitious material is 4% of the dry soil mass of carbide slag and 6% of the dry soil mass of fly ash. The anhydrous sodium sulfate content is 0.3% of the dry soil mass. The sisal fiber length is 11mm, and the sisal fiber content is 0.6% of the dry soil mass. The mass percentage concentration of the NaOH solution is 10%.

[0051] Step 1: Use deionized water to wash the sisal fiber to remove impurities on its surface, then place it in a ventilated environment to dry naturally until constant weight, and then completely immerse the sisal fiber in a pre-prepared NaOH solution for 12 hours before taking it out for use;

[0052] Step 2: fully mix the sisal fiber obtained by the first step with the dry soil, then add water according to the optimal moisture content and mix evenly to make a sisal fiber wet soil mixture, and seal and let it stand for more than 24 hours;

[0053] Step 3: adding the solid waste-based cementitious material and anhydrous sodium sulfate to the sisal fiber wet soil mixture obtained in the second step in sequence, and stirring evenly;

[0054] Step 4: Weigh 4.5% of the dry soil mass in water and add it to the mixture prepared in Step 3. Stir thoroughly to obtain a solid waste-based cementitious material-fiber-solidified soil mixture. The mixture is then loaded into a cylindrical mold with an inner diameter of 39.1 mm and a height of 80 mm in three batches. After static compaction, the mold is removed to produce the solidified soil sample. Finally, the demolded sample is wrapped and placed in a standard curing chamber for curing for 7 days. The sample is then removed and subjected to an unconfined compressive strength test to determine the unconfined compressive strength of the solid waste-based cementitious material-fiber-solidified soil sample.

[0055] Example 6:

[0056] A solid waste-based cementitious material is used in conjunction with fiber to solidify soil. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil. The optimal moisture content of the soil (18%) is measured; the solid waste-based cementitious material is added in an amount of 10% of the dry soil mass; the carbide slag-fly ash system in the solid waste-based cementitious material is 4% of the dry soil mass of carbide slag and 6% of the dry soil mass of fly ash; the anhydrous sodium sulfate content is 0.3% of the dry soil mass; the sisal fiber length is 11mm, and the sisal fiber content is 0.6% of the dry soil mass; and the mass percentage concentration of the NaOH solution is 6%.

[0057] The preparation method of the solid waste-based cementitious material and fiber-solidified soil in this embodiment is the same as that in Example 5.

[0058] Example 7:

[0059] A solid waste-based cementitious material is used to solidify soil using fibers. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil. The optimal moisture content of the soil (18%) is measured. The solid waste-based cementitious material is added in an amount of 10% of the dry soil mass. The carbide slag-fly ash system in the solid waste-based cementitious material is 4% of the dry soil mass of carbide slag and 6% of the dry soil mass of fly ash. The anhydrous sodium sulfate content is 0.3% of the dry soil mass. The sisal fiber length is 11mm, and the sisal fiber content is 0.6% of the dry soil mass. The mass percentage concentration of the NaOH solution is 10%.

[0060] Step 1: Add the water required for dry soil according to the optimal moisture content, stir evenly to make wet soil, and then seal and let it stand for more than 24 hours;

[0061] Step 2: Use deionized water to wash the sisal fiber to remove impurities on its surface, then place it in a ventilated environment to dry naturally until constant weight, and then completely immerse the sisal fiber in the pre-prepared NaOH solution for 12 hours before taking it out for use;

[0062] Step 3: Weigh the required mass of the sisal fiber, solid waste-based gelling material and anhydrous sodium sulfate obtained in the second step respectively, first fully and evenly wrap the solid waste-based gelling material with the sisal fiber obtained in the second step, and then add the sisal fiber, solid waste-based gelling material and anhydrous sodium sulfate to the wet soil in sequence and mix them evenly;

[0063] Step 4: Weigh 4.5% of the dry soil mass in water and add it to the mixture prepared in Step 3. Stir thoroughly to obtain a solid waste-based cementitious material-fiber-solidified soil mixture. The mixture is then loaded into a cylindrical mold with an inner diameter of 39.1 mm and a height of 80 mm in three batches. After static compaction, the mold is removed to produce the solidified soil sample. Finally, the demolded sample is wrapped and placed in a standard curing chamber for curing for 7 days. The sample is then removed and subjected to an unconfined compressive strength test to determine the unconfined compressive strength of the solid waste-based cementitious material-fiber-solidified soil sample.

[0064] Example 8:

[0065] A solid waste-based cementitious material is used in conjunction with fiber to solidify soil. The original soil is dried and crushed, and then passed through a 2mm sieve to obtain dry soil. The optimal moisture content of the soil (18%) is measured; the solid waste-based cementitious material is added in an amount of 10% of the dry soil mass; the carbide slag-fly ash system in the solid waste-based cementitious material is 4% of the dry soil mass of carbide slag and 6% of the dry soil mass of fly ash; the anhydrous sodium sulfate content is 0.3% of the dry soil mass; the sisal fiber length is 11mm, and the sisal fiber content is 0.6% of the dry soil mass; and the mass percentage concentration of the NaOH solution is 6%.

[0066] The preparation method of the solid waste-based cementitious material and fiber-solidified soil in this embodiment is the same as that in Example 7.

[0067] Unconfined compressive strength test:

[0068] The unconfined compressive strength test was performed on the solid waste-based cementitious material-solidified soil samples and the solid waste-based cementitious material-co-fiber-solidified soil samples of Examples 1, 2, 3, 4, 5, 6, 7, and 8. The test method is as follows:

[0069] Unconfined compressive strength tests were conducted using an electronic universal testing machine, with a loading rate set at 1 mm / min. During the test, the specimen, after reaching the designed curing age, was placed in the center of the compression platen of the compression testing machine to ensure even horizontal contact between both ends of the specimen. The loading test was then carried out.

[0070] The unconfined compressive strength test results are shown in Figure 8 .

[0071] from Figure 8 The variation pattern of the unconfined compressive strength of the solidified soil specimens at 7 days can be seen in the figure.

[0072] (1) By comparing Examples 1, 2, and 3, it can be seen that when the content of carbide slag and fly ash is 4% and 6% of the dry soil mass, respectively, the compressive strength of the soil solidified with solid waste-based cementitious materials is the highest.

[0073] (2) The compressive strength of the solid waste-based cementitious materials and fiber-solidified soil samples of Examples 4, 5, 6, 7 and 8 was significantly higher than that of Examples 1, 2 and 3, confirming that the addition of 0.6% sisal fiber can significantly enhance the compressive strength of the solidified soil.

[0074] (3) The compressive strength of the solid waste-based cementitious materials and fiber-stabilized soil samples of Examples 5, 6, 7 and 8 was significantly higher than that of Example 4, indicating that the sisal fibers pretreated with NaOH solution can improve the strength of the stabilized soil compared with the sisal fibers not pretreated with NaOH solution.

[0075] (4) The compressive strength of the solid waste-based cementitious materials and fiber-solidified soil samples in Examples 7 and 8 is significantly higher than that in Examples 5 and 6, indicating that the mixing methods of Examples 7 and 8 can obtain solid waste-based cementitious materials and fiber-solidified soil samples with higher compressive strength. The internal mechanism is as follows: Examples 5 and 6 directly add pretreated sisal fibers when mixing the soil, and at this time mainly rely on the physical reinforcement effect of sisal fibers on the solidified soil; while Examples 7 and 8 use solid waste-based cementitious materials to uniformly wrap the pretreated sisal fibers, which can form a dense hydration product layer on the surface of the sisal fibers. This method helps to optimize the mechanical bite and chemical bonding between the sisal fibers and the solidified soil matrix, significantly strengthen the strength of the interface transition zone, and reduce internal defects, ultimately improving the overall strength of the solidified soil.

[0076] (5) The compressive strength of the solid waste-based cementitious material and fiber-solidified soil sample in Example 8 is higher than that in Example 7, indicating that the improvement effect after pretreatment with a 6% concentration of NaOH solution is higher than that with a 10% concentration. This is because after pretreatment with a 10% concentration of NaOH solution, the sisal fibers in Example 7 underwent the following structural changes: a large amount of lignin was removed, hemicellulose was significantly degraded, and the fiber chemical bond structure underwent irreversible depolymerization and was difficult to reconnect. This excessive erosion caused the sisal fiber's bearing capacity to decline significantly. In Example 8, the 6% NaOH solution pretreatment effectively removed the oily impurities on the surface of the sisal fiber and significantly improved the surface roughness of the sisal fiber, which not only facilitated the adhesion of the gel material generated by the hydration reaction of the solid waste-based cementitious material, but also improved the water absorption of the sisal fiber and the interfacial bonding performance between the sisal fiber and the solidified soil matrix by hydrolyzing the internal hydroxyl groups. In addition, combined with the inherent mechanical anchoring effect of the sisal fiber, the mechanical properties of the solidified soil were finally synergistically enhanced.

[0077] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, through the above description, ordinary technicians in this field can modify the technical solutions described in the aforementioned embodiments, or replace some of the technical features therein with equivalents, and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A solid waste-based cementitious material and fiber-solidified soil, characterized in that: It includes wet soil, solid waste-based cementitious materials, sisal fiber, water and anhydrous sodium sulfate; the wet soil is made by mixing dry soil and water, and the moisture content of the wet soil is the optimal moisture content of the soil; the mass content of the solid waste-based cementitious materials, sisal fiber, water and anhydrous sodium sulfate are 10%, 0.6%, 4.5% and 0.3% of the dry soil respectively.

2. The solid waste-based cementitious material and fiber-solidified soil according to claim 1, characterized in that: The solid waste-based cementitious material includes the following raw materials in percentage by mass: 4% of dry soil mass of carbide slag and 6% of dry soil mass of fly ash.

3. The solid waste-based cementitious material and fiber-solidified soil according to claim 1, characterized in that: The sisal fiber length is 11 mm.

4. The method for preparing solid waste-based cementitious materials and fiber-solidified soil according to claims 1-3, characterized in that: The following steps are involved: Step 1: Dry the original soil, crush it, and screen it to obtain dry soil, and then determine the optimal moisture content of the soil. Step 2: Add the water required for dry soil according to the optimal moisture content, stir evenly to make wet soil, seal it and let it stand for more than 24 hours; Step 3: Use deionized water to wash the sisal fiber to remove impurities on its surface, then place it in a ventilated environment to dry naturally to constant weight, and completely immerse the treated sisal fiber in a pre-prepared NaOH solution with a concentration of 6% by mass for 12 hours before taking it out for use; Step 4: Weigh 4% of the dry soil mass of calcium carbide slag and 6% of the dry soil mass of fly ash, mix them evenly and prepare a solid waste-based cementitious material; Step 5: Use the solid waste-based gelling material from step 4 to fully and evenly wrap the sisal fibers from step 3; Step 6: Weigh 0.3% of the mass of dry soil with anhydrous sodium sulfate, and add the sisal fiber, solid waste-based cementitious material, and anhydrous sodium sulfate obtained in step 5 to the wet soil in sequence and mix evenly; Step 7: Weigh 4.5% of the dry soil mass of water and add it to the mixture prepared in step 6, and stir thoroughly to obtain a solid waste-based cementitious material and fiber-solidified soil mixture.

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