A full-solid-waste aggregate grouting body and a preparation method thereof

Abstract

The application relates to the technical field of full-solid-waste grouting bodies, in particular to a full-solid-waste aggregate grouting body and a preparation method thereof. The full-solid-waste aggregate grouting body comprises a grouting body and pretreated desert sand. The grouting body comprises a base material, a composite additive and water. According to mass fractions, the base material comprises 25-40 parts of pretreated coal gangue, 15-25 parts of modified carbide slag, 25-35 parts of blast furnace slag and 10-25 parts of superfine fly ash; the mass of the composite additive is 5-12% of the mass of the base material, the composite additive comprises hydrogenated coconut oil acid, glucosyl rutin and ethylene-vinyl acetate copolymer emulsion in a mass ratio of (2-3):3:4; the mass ratio of the water to the base material is (0.3-0.35):1; and the mass of the pretreated desert sand is 40% of the mass of the grouting body. The application provides a full-solid-waste aggregate grouting body and a preparation method thereof, so as to solve the problem that the strength and stability of the grouting body in the prior art are difficult to adapt to a desert environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of full-solid-waste grouting body, and particularly relates to a full-solid-waste aggregate grouting body and a preparation method thereof. BACKGROUND

[0002] With the rapid development of industrialization, the output of bulk industrial solid waste shows a rapid growth trend. Industrial waste not only occupies a large amount of land, but also causes waste of manpower and material resources. There are a large amount of substances dissolved in water in industrial waste, which pollutes the land, groundwater and air environment. For example, coal gangue, carbide slag, blast furnace slag and other solid waste. The preparation of the full-solid-waste aggregate grouting body from the above industrial solid waste is beneficial to the resourceization and high-value utilization of industrial solid waste.

[0003] The current grouting material is composed of cement and other components. The cement industry is a major consumer of energy consumption and carbon emissions.

[0004] Desert accounts for more than one-third of the global land area. The geological conditions of desert regions are complex. The geology of desert regions is usually composed of aeolian sand. Such soil has poor stability and insufficient cohesion, and is prone to collapse during drilling. It is difficult to form a hole and cannot be drilled into a cast-in-place pile. Therefore, in desert regions, the method of grouting into a steel pipe pile is usually selected to meet the purpose of resisting compression and uplift of the steel pipe pile.

[0005] The grouting body needs to smoothly pass through the delivery pipe and fill the gap around the steel pipe. Therefore, it needs to have good fluidity and passability. At the same time, in order to ensure the stability of the steel pipe pile, the grouting body needs to have high strength to withstand the load of the steel pipe pile and the pressure of the surrounding soil. In addition, in the high temperature and sandy environment of desert regions, the grouting body also needs to have good volume stability and is not prone to shrinkage, cracking and other phenomena. The climate in desert regions is harsh, with strong sand and large temperature changes. High requirements are put forward for the durability of the grouting body. SUMMARY

[0006] The present application provides a full-solid-waste aggregate grouting body and a preparation method thereof, to solve the problem that the strength and stability of the grouting body in the related art are difficult to adapt to the desert environment.

[0007] In a first aspect, a full-solid-waste aggregate grouting body is provided, which comprises a grouting body and pretreated desert sand:

[0008] The grouting body comprises a base material, a composite additive and water;

[0009] According to mass fraction, the base material comprises 25-40 parts of pretreated coal gangue, 15-25 parts of modified carbide slag, 25-35 parts of blast furnace slag and 10-25 parts of ultra-fine fly ash;

[0010] The mass of the composite additive is 5-12% of the mass of the base material, and the composite additive comprises hydrogenated coconut oil acid, glucosyl rutin and ethylene-vinyl acetate copolymer emulsion in a mass ratio of (2-3):3:4;

[0011] The mass ratio of the water to the base material is (0.3-0.35):1;

[0012] The mass of the pretreated desert sand is 40% of the mass of the slurry.

[0013] Preferably, the method for preparing the pretreated desert sand comprises the following steps:

[0014] After the desert sand is passed through a 30-mesh sieve, the desert sand is soaked in 0.1 mol / L oxalic acid solution for 1.5-2 h, washed with clean water until neutral, and dried at 100-105°C to obtain the pretreated desert sand.

[0015] Preferably, the method for preparing the pretreated coal gangue comprises the following steps:

[0016] After the coal gangue and the modified liquid are mixed in a mass ratio of 1:(0.1-0.25), the mixture is stirred in a water bath at 80°C for 55-60 min, and then cured for 24 h to obtain the pretreated coal gangue.

[0017] The modified liquid comprises pyroligneous liquid, concha malleabilis powder and water in a mass ratio of 3:(2-3):100.

[0018] Preferably, the particle size of the coal gangue is 3-4.5 cm.

[0019] Preferably, the method for preparing the modified carbide slag comprises the following steps: passing the carbide slag through a 200-mesh sieve, then placing the sieved carbide slag in a muffle furnace, heating the carbide slag to 750-760°C at a rate of 20°C / min, and calcining the carbide slag at 750-760°C for 1-2.5 h; after the calcination is completed, the carbide slag is taken out of the muffle furnace and allowed to cool to room temperature to obtain the calcined carbide slag.

[0020] The calcined carbide slag is mixed with a sodium hydroxide solution and stirred, and the drained material is used as the modified carbide slag.

[0021] Preferably, the method for preparing the superfine fly ash comprises the following steps: mixing the fly ash and lauryl amide, feeding the mixture into a ball mill for 1.5-2 h of grinding, and sieving the ground mixture through a 400-mesh sieve to obtain the superfine fly ash, wherein the mass of the lauryl amide is 2% of the mass of the fly ash.

[0022] Preferably, the composite additive further comprises polyether sulfonated oil and magnesium silicate in a mass ratio of 1:0.5, and the mass of the polyether sulfonated oil is 20% of the mass of the ethylene-vinyl acetate copolymer emulsion.

[0023] Preferably, the preparation method of the blast furnace slag is that the blast furnace slag is taken, crushed and sieved to obtain particles of 0.15-5 mm, dried at 100-105 DEG C for 1.5-2 h to obtain the blast furnace slag.

[0024] In a second aspect, a preparation method for preparing the full-solid-waste aggregate grouting body is provided, and the method comprises the following steps:

[0025] S1, mixing the base material to prepare the cementitious material: the modified carbide slag, the blast furnace slag and the ultra-fine fly ash are added into a stirrer and stirred at a speed of 140 r / min for 3-5 min, water is added according to a water-binder ratio of 0.3-0.35, and the stirring is continued at a speed of 140 r / min for 3-5 min, and then the pretreated coal gangue is added and stirred at a speed of 280 r / min for 3-5 min to obtain the cementitious material;

[0026] S2, adding the composite modifier to obtain the slurry: the composite modifier is added into the cementitious material, and stirred at a speed of 800 r / min for 10-15 min to obtain the slurry;

[0027] S3, adding the pretreated desert sand into the slurry, and using a vacuum stirrer to stir at a pressure of-0.08 MPa and a speed of 200 r / min for 5-10 min to obtain the full-solid-waste aggregate grouting body.

[0028] The technical scheme provided by the application has the following beneficial effects:

[0029] The application provides a full-solid-waste aggregate grouting body and a preparation method thereof, which uses solid wastes such as coal gangue, carbide slag, blast furnace slag and ultra-fine fly ash as base material to construct a high-strength skeleton, wherein the pretreated coal gangue has more active points, which can promote the generation of C-S-H gel, AFt and other strength phases together with the carbide slag and the blast furnace slag; the hydrogenated coconut oil in the composite additive plays a lubricating and drag-reducing role, reduces the friction between the solid waste particles and the desert sand, and cooperates with the dispersion effect of the polyether sulfonated oil to make the base material and the aggregate uniformly distributed in the slurry; the ethylene-vinyl acetate copolymer emulsion fills the pores in a fluid state in the early stage, improves the cohesiveness of the slurry, makes the grouting body have good construction fluidity, and meets the pouring demand. Meanwhile, after the pretreated desert sand is fully combined with the slurry, the slurry can effectively wrap and bond the desert sand particles, and use its own strength and bonding force to achieve better fixing and combining effect in the desert environment. Through reasonable proportioning and process control, the grouting body can form a synergistic effect with the desert sand, so that the loose desert sand has higher overall integrity and stability after grouting, and thus is suitable for reinforcement, repair and other engineering needs in the desert sand environment. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0031] Figure 1 The preparation method flowchart of the full-solid-waste aggregate grouting body provided by the present application is shown in the following figure:

[0032] Figure 2 The XDR graph of the full-solid-waste aggregate grouting body test piece prepared in Example 1 provided by the present application is shown in the following figure:

[0033] Figure 3 The XRD spectrum of the full-solid-waste aggregate grouting body test piece prepared in Example 1 provided by the present application is shown in the following figure:

[0034] Figure 4 The TG-DSC change curve of the full-solid-waste aggregate grouting body test piece prepared in Example 1 provided by the present application is shown in the following figure:

[0035] Figure 5 The FTIR change curve of the full-solid-waste aggregate grouting body test piece prepared in Example 1 provided by the present application is shown in the following figure:

[0036] Figure 6 The scanning electron microscope graphs of the full-solid-waste aggregate grouting body test piece prepared in Example 1 provided by the present application at 3d and 28d are shown in the following figures. DETAILED DESCRIPTION

[0037] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort belong to the scope of protection of the present application.

[0038] Referring to Figures 1-6 The present application provides a full-solid-waste aggregate grouting body and a preparation method thereof.

[0039] Example 1

[0040] The preparation method of the full-solid-waste aggregate grouting body provided by the present application is as follows:

[0041] S101, mixing binders to prepare cementitious material: 200g modified carbide slag, 300g blast furnace slag and 200g ultra-fine fly ash are added into a stirrer, stirred at a speed of 140r / min for 3min, 320g water is added, and stirring is continued at a speed of 140r / min for 3min, then 300g pretreated coal gangue is added, and stirring is carried out at a speed of 280r / min for 5min to obtain a cementitious material;

[0042] S102, adding a composite modifier to obtain a slurry: 100g of the composite modifier is added to the cementitious material prepared in S101, stirred at 800r / min for 10min to obtain a slurry;

[0043] S103, 400g of pretreated desert sand is added to the slurry, a vacuum stirrer is used, stirring is carried out at -0.08MPa and 200r / min for 10min to obtain a full-solid-waste aggregate grouting body.

[0044] In S101, the preparation method of the modified carbide slag is as follows: the carbide slag is passed through a 200-mesh sieve, then the sieved carbide slag is placed in a muffle furnace, heated to 760℃ at a rate of 20℃ / min, and calcined at 760℃ for 2.5h, after calcination, the carbide slag is taken out of the muffle furnace and air-dried to room temperature to obtain calcined carbide slag.

[0045] 300g of the calcined carbide slag is mixed with 100g of a 1mol / L sodium hydroxide solution, and the drained material is used as the modified carbide slag.

[0046] The preparation method of the blast furnace slag is as follows: the blast furnace slag is taken, crushed and sieved to obtain particles of 0.15-5mm, dried at 105℃ for 1.5h to obtain the blast furnace slag.

[0047] The preparation method of the ultra-fine fly ash is as follows: 300g of fly ash and 6g of lauryl amide are mixed and then fed into a ball mill for grinding for 1.5h, after grinding, the product is sieved through a 400-mesh sieve to obtain the ultra-fine fly ash.

[0048] The preparation method of the pretreated coal gangue is as follows: 400g of coal gangue with a particle size of 3-4.5cm is mixed with 80g of a modified liquid, stirred in a water bath at 80℃ for 60min, and then cured at room temperature for 24h to obtain the pretreated coal gangue.

[0049] The modified liquid is composed of 3g of wood vinegar, 2g of conchiolin powder and 100g of water.

[0050] In S102, the composite modifier is a combination of 30g of hydrogenated coconut oil, 30g of glucosyl rutin, 40g of ethylene-vinyl acetate copolymer emulsion, 8g of polyether sulfonated oil and 4g of magnesium silicate, wherein the solid content of the ethylene-vinyl acetate copolymer emulsion is 50%.

[0051] In S103, the preparation method of the pretreated desert sand is as follows: the desert sand is sieved through a 30-mesh sieve, then soaked in 0.1 mol / L oxalic acid solution for 1.5 h, washed with water until neutral, and dried at 105℃ to obtain the pretreated desert sand.

[0052] Example 2

[0053] The difference between the present example and Example 1 is that the preparation method of the full-solid-waste aggregate grouting body provided by the present example is as follows:

[0054] S201, mixing the binder to prepare the cementitious material: 150 g of modified carbide slag, 350 g of blast furnace slag, and 250 g of ultra-fine fly ash are added into a blender, stirred at a speed of 140 r / min for 3 min, 320 g of water is added, and the stirring is continued at a speed of 140 r / min for 3 min, then 250 g of pretreated coal gangue is added, and stirred at a speed of 280 r / min for 5 min to obtain the cementitious material;

[0055] S202, adding the composite modifier to obtain the slurry: 100 g of the composite modifier is added into the cementitious material prepared in S201, and stirred at a speed of 800 r / min for 10 min to obtain the slurry;

[0056] S203, adding 400 g of pretreated desert sand into the slurry, and using a vacuum blender to stir at a pressure of-0.08 MPa and a speed of 200 r / min for 10 min to obtain the full-solid-waste aggregate grouting body.

[0057] The preparation methods of the pretreated coal gangue, the modified carbide slag, the blast furnace slag, the ultra-fine fly ash, the composite modifier, and the pretreated desert sand, as well as the components, are the same as those in Example 1.

[0058] Example 3

[0059] The difference between the present example and Example 1 is that the composite modifier includes 30 g of hydrogenated coconut oil acid, 30 g of glucosyl rutin, and 40 g of ethylene-vinyl acetate copolymer emulsion, the composite modifier accounts for 10% of the mass of the binder, and the total actual addition amount is 100 g.

[0060] Example 4

[0061] The difference between the present example and Example 1 is that the composite modifier accounts for 5% of the mass of the binder, and the total addition amount is 50 g.

[0062] Example 5

[0063] The preparation method of the full-solid-waste aggregate grouting body provided by the present application is as follows:

[0064] S501, mixing binders to prepare cementitious material: 250 g of modified carbide slag, 250 g of blast furnace slag and 100 g of superfine fly ash are added into a stirrer, stirred at a speed of 140 r / min for 5 min, 300 g of water is added, and stirring is continued at a speed of 140 r / min for 5 min, then 400 g of pretreated coal gangue is added, and stirring is carried out at a speed of 280 r / min for 3 min, to obtain a cementitious material;

[0065] S502, adding a composite modifier to obtain a slurry: 120 g of a composite modifier is added to the cementitious material prepared in S501, stirred at 800 r / min for 15 min to obtain a slurry;

[0066] S503, 400 g of pretreated desert sand is added to the slurry, and a vacuum stirrer is used to stir at -0.08 MPa and 200 r / min for 5 min to obtain a full-solid-waste aggregate grouting body.

[0067] In S501, the preparation method of the modified carbide slag is as follows: the carbide slag is passed through a 200-mesh sieve, then the sieved carbide slag is placed in a muffle furnace, heated to 750℃ at a rate of 20℃ / min, and calcined at 760℃ for 1 h. After calcination, the carbide slag is taken out of the muffle furnace and allowed to cool to room temperature to obtain calcined carbide slag.

[0068] 300 g of calcined carbide slag is mixed with 100 g of a 1 mol / L sodium hydroxide solution, and the drained material is used as the modified carbide slag.

[0069] The preparation method of the blast furnace slag is as follows: the blast furnace slag is taken, crushed and sieved to obtain particles of 0.15-5 mm, and dried at 100℃ for 2 h to obtain the blast furnace slag.

[0070] The preparation method of the superfine fly ash is as follows: 300 g of fly ash and 6 g of lauryl amide are mixed and then fed into a ball mill for grinding for 2 h. After grinding, the material is sieved through a 400-mesh sieve to obtain the superfine fly ash.

[0071] The preparation method of the pretreated coal gangue is as follows: 450 g of coal gangue with a particle size of 3-4.5 cm is mixed with 45 g of a modified liquid, stirred in a water bath at 80℃ for 55 min, and then allowed to stand and cure for 24 h to obtain the pretreated coal gangue.

[0072] The modified liquid is composed of 3 g of wood vinegar, 3 g of conchiolin powder and 100 g of water.

[0073] In S502, the composite modifier is a combination of 28 g of hydrogenated coconut oil, 42 g of glucosyl rutin, 56 g of ethylene-vinyl acetate copolymer emulsion, 11.2 g of polyether sulfonated oil and 5.6 g of magnesium silicate, wherein the ethylene-vinyl acetate copolymer emulsion has a solid content of 50%.

[0074] In S503, the method for preparing pretreated desert sand is as follows: after passing the desert sand through a 30-mesh sieve, it is soaked in a 0.1 mol / L oxalic acid solution for 2 hours, rinsed with water until neutral, and dried at 100℃ to obtain pretreated desert sand.

[0075] Comparative Example 1

[0076] The difference between this comparative example and Example 1 is that the composite additive is replaced with an equal amount of water.

[0077] Comparative Example 2

[0078] The difference between this comparative example and Example 1 is that the pretreated coal gangue was replaced with an equal amount of untreated coal gangue, and the composite additive was replaced with an equal amount of water.

[0079] Comparative Example 3

[0080] The difference between this comparative example and Example 1 is that the desert sand is not pretreated, and the pretreated desert sand in S103 is replaced with an equal amount of desert sand.

[0081] The solid waste aggregate grouting bodies (hereinafter referred to as grouting bodies) prepared by the preparation methods of Examples 1-5 and Comparative Examples 1-3 were tested.

[0082] Flowability test: Refer to GB / T 2419-2005 "Method for Determination of Flowability of Cement Mortar", pour the grout into a truncated cone mold (upper diameter 70mm, lower diameter 100mm, height 60mm), vibrate 25 times, lift the mold, and after 30 seconds, use calipers to measure the diameter of the bottom surface of the grout in two mutually perpendicular directions, and take the average value as the spread.

[0083] Compressive strength test: Referring to GB / T17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)", the grouting body was made into cubic test blocks of 40mm×40mm×160mm. After standard curing (temperature 20±2℃, relative humidity ≥95%) for 28 days, the compressive strength was tested using a pressure testing machine at a loading rate of 2.4kN / s. The average value of 6 test blocks was taken as the 28-day compressive strength.

[0084] Shrinkage test: Refer to the drying shrinkage test method in GB / T11969-2008 "Test Methods for Performance of Autoclaved Aerated Concrete". Prepare cubic specimens of 40mm×40mm×160mm from the grout. Drill a hole with a diameter of 80mm and a depth of 13mm at the center of each of the two end faces of the specimen to embed the shrinkage head. After 1 day, immerse the specimen in a constant temperature water bath at (20±2)℃ for 72 hours. Measure the length after 28 days. Shrinkage rate = (initial length - 28-day length) / initial length × 100%.

[0085] The experimental results are shown in Table 1.

[0086] Table 1

[0087]

[0088] Compared to Example 1, Example 2 has a lower proportion of pretreated coal gangue and modified calcium carbide slag, resulting in lower strength. Compared to Example 1, Example 3's composite additive lacks polyether sulfonated oil and magnesium silicate, leading to a decrease in fluidity.

[0089] Comparative Examples 1 and 2, which did not contain any composite additives, showed significant hydration shrinkage and decreased fluidity. The desert sand in Comparative Example 3, which was not pretreated, had poor interparticle bonding and thus a larger shrinkage rate.

[0090] Furthermore, the compressive strength of the specimens prepared in Example 1 at various ages is shown in Table 2.

[0091] Table 2

[0092]

[0093] As can be seen from Tables 1 and 2, Example 1 has better overall performance. The pretreated coal gangue and modified carbide slag can participate in the hydration reaction better. The ethylene-vinyl acetate copolymer emulsion in the composite additive forms an elastic network, which can relieve stress and effectively reduce shrinkage. Magnesium silicate activates the activity of blast furnace slag and improves the overall strength through the synergistic effect of multiple mechanisms such as lubrication, shrinkage inhibition and toughening.

[0094] See Figure 2 As shown, it is an XDR image of the grout body prepared in Example 1.

[0095] The main mineral component of carbide slag, Ca(OH)2, decomposes at 510℃ and then reacts with CO2 in the air, decomposing into CaCO3 at 720℃. After calcination, it is converted into calcium oxide. Coal gangue contains a large amount of silicon dioxide and aluminum oxide, which can react with calcium oxide, making it bond more firmly with other base materials. This increases the friction between the solid waste aggregate grout and the sandy soil outside the pile body, further improving the compressive and tensile bearing capacity of the steel pipe pile.

[0096] See Figures 3-5 As shown, the XRD pattern, TG-DSC curve, and FTIR curve of the grout specimen prepared in Example 1 are displayed in sequence. Figure 3 As can be seen, ettringite (AFt) exhibits distinct characteristic peaks at different ages (6h, 1d, 3d, 7d, 28d), which increase with age, indicating its continuous formation over a longer period. This is beneficial for consolidating the strength of the grout specimens. The filling and cementing effects of hydration products make the grout specimens structurally dense, thus improving their load-bearing capacity.Figure 4 It can be seen that the mass loss rate gradually decreases with the extension of the curing period; the slower the mass loss rate and the smaller the loss amount in the 200~600℃ stage, the more stable the hydration products become and the denser the structure. After 600℃, the mass loss rate of the TG curve slows down. In the early stage (6h~3d), it is mainly free water evaporation, indicating the formation of early hydration products (such as AFt) and ensuring fluidity. In the middle stage (3d~7d), the hydration products tend to be stable, and in the later stage (7d~28d), the grout specimen has formed a stable and dense structure. From Figure 5 It can be known that 800~1200cm -1 The characteristic absorption of silicate hydration products such as CSH gel shows that the peaks become sharper and stronger with age, indicating that CSH gel is continuously generated and its crystallinity increases. The silicate hydration reaction of the grout continues and the structure gradually becomes denser.

[0097] as well as, Figure 6 The images are scanning electron microscope (SEM) images of the grout specimen prepared in Example 1 at 3 days and 28 days.

[0098] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A solid waste aggregate injection body, characterized in that, It includes slurry and pretreated desert sand: The slurry includes a base material, composite additives, and water; According to the mass fractions, the base material includes 25-40 parts of pretreated coal gangue, 15-25 parts of modified carbide slag, 25-35 parts of blast furnace slag, and 10-25 parts of ultrafine fly ash. The preparation of the pretreated coal gangue includes the following steps: Coal gangue and modification liquid were mixed at a mass ratio of 1:(0.1~0.25), stirred in an 80℃ water bath for 55~60 min, and then allowed to stand for 24 h to obtain pretreated coal gangue. The modified liquid comprises wood vinegar, shell protein powder, and water in a mass ratio of 3:(2~3):100; The modified calcium carbide slag is prepared by passing the calcium carbide slag through a 200-mesh sieve, then placing the sieved calcium carbide slag into a muffle furnace for calcination, heating it to 750~760℃ at a rate of 20℃ / min, and calcining it at 750~760℃ for 1~2.5h. After calcination, the calcium carbide slag is removed from the muffle furnace and cooled to room temperature to obtain calcined calcium carbide slag. The calcined carbide slag was mixed with sodium hydroxide solution and stirred. The drained product was used as modified carbide slag. The mass of the composite additive is 5-12% of the mass of the base material, and the composite additive includes hydrogenated coconut oil acid, glucosyl rutin and ethylene-vinyl acetate copolymer emulsion in a mass ratio of (2-3):3:

4. The ratio of the mass of water to the mass of the base material is (0.3~0.35):1; The pretreated desert sand accounts for 40% of the mass of the slurry, and the method for preparing the pretreated desert sand includes the following steps: After passing desert sand through a 30-mesh sieve, it is soaked in a 0.1 mol / L oxalic acid solution for 1.5 to 2 hours, rinsed with water until neutral, and dried at 100 to 105°C to obtain pretreated desert sand.

2. The solid waste aggregate injection body as described in claim 1, characterized in that: The particle size of the coal gangue is 3~4.5cm.

3. The solid waste aggregate injection body as described in claim 1, characterized in that: The method for preparing ultrafine fly ash is as follows: fly ash and lauramide are mixed and then put into a ball mill for grinding for 1.5 to 2 hours. After grinding, the mixture is passed through a 400-mesh sieve to obtain ultrafine fly ash. The mass of lauramide is 2% of the mass of fly ash.

4. The solid waste aggregate injection body as described in claim 1, characterized in that: The method for preparing blast furnace slag is as follows: take blast furnace slag, crush and screen it to obtain particles of 0.15~5mm, and dry it at 100~105℃ for 1.5~2h to obtain blast furnace slag.

5. A method for preparing a solid waste aggregate grout body as described in any one of claims 1 to 4, characterized in that, It includes the following steps: S1. Mixing base materials to prepare cementitious materials: Add modified carbide slag, blast furnace slag and ultrafine fly ash into a mixer and stir at 140 r / min for 3-5 min. Add water at a water-cement ratio of 0.3-0.35 and continue stirring at 140 r / min for 3-5 min. Then add pretreated coal gangue and stir at 280 r / min for 3-5 min to obtain cementitious materials. S2. Add composite modifier to obtain slurry: Add composite modifier to the cementitious material and stir at 800 r / min for 10-15 min to obtain slurry; S3. Add pretreated desert sand to the slurry and stir it for 5-10 minutes at -0.08MPa and 200r / min using a vacuum mixer to obtain a solid waste aggregate grout.

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