Fluidized solidified soil preparation device for foundation pit backfilling and backfilling method

Abstract

The preparation device comprises a transport vehicle, a water supply assembly, a curing agent storage cabin, a curing agent slurry preparation cabin, a crushing assembly and a preparation assembly are arranged above the transport vehicle, and the water supply assembly is connected with the curing agent slurry preparation cabin and the preparation assembly through pipelines. The curing agent storage cabin is connected with the curing agent slurry preparation cabin through a curing agent raw material conveying pipe, the crushing assembly is arranged above the preparation assembly, and the screening assembly is arranged above the transport vehicle and connected with the crushing assembly; the screening assembly comprises a screen, a supporting framework and a material sliding plate which are connected up and down, and an eccentric vibration motor is arranged on the bottom surface of the material sliding plate; a stirring cabin and a product storage cabin are arranged in the preparation assembly, the stirring cabin comprises a stirring cabin shell, a stirring roller is arranged at the center in the stirring cabin shell, a motor is arranged in the stirring roller, and a stirring roller shell is fixed outside the stirring roller.

Description

Technical Field

[0001] The invention relates to the technical field of mud mixing, and in particular to a fluidized solidified soil preparation device and a backfilling method for foundation pit backfilling. Background Art

[0002] In the process of backfilling foundation pits in many projects, we often face many challenges, such as small backfilling space, large backfilling depth, unstable backfilling soil compaction quality and high backfilling soil quality requirements. In recent years, with the increasing number of deep foundation pit support projects, the insufficient compaction of backfill soil has caused settlement damage to the building's scattered water, pipelines, access roads and other parts, thus affecting their use functions. Fluidized solidified soil is a new type of building material specially studied and innovatively developed to address the above problems.

[0003] However, the preparation and application of fluidized soil currently face some technical problems. First, the transportation cost of raw materials is high, especially when the source of raw materials is far away, which increases the overall project cost. Secondly, the raw materials often contain large-sized stones and lumps of soil. These impurities will affect the uniformity and stability of the fluidized soil, thereby reducing its quality. In addition, fluidized soil also has the problem of high cost during transportation, which is mainly due to its special fluidity and requirements for transportation conditions. Therefore, how to reduce the transportation cost of raw materials and fluidized soil, and how to effectively deal with large-sized stones and lumps of soil in the raw materials are key issues that need to be solved in the current fluidized soil technology.

[0004] For example, the invention patent "Movable Fluidized Solidified Soil Production and Transportation Vehicle", application number: 202410211659.5, prepares fluidized solidified soil by carrying storage tanks and mixing tanks on the vehicle body, saving transportation costs, but it cannot handle slag, and the prepared fluidized solidified soil has poor uniformity and stability, and cannot be prepared continuously, affecting the progress of the project; based on the characteristics of fluidized solidified soil, a specific backfilling method is required when backfilling the foundation pit. Summary of the invention

[0005] The purpose of the present invention is to solve the problems raised in the above-mentioned background technology, and then propose a fluidized solidified soil preparation device and backfilling method for foundation pit backfilling. The device disclosed in the present invention filters large-size stones and soil blocks by setting a screening component with an aperture of 50 mm, and obtains soil materials that meet the "Technical Standard for Application of Fluidized Solidified Soil" T / SDSZ 8-2023 standard, avoiding complicated crushing processes, reducing costs, and improving the uniformity and stability of fluidized solidified soil; by setting a product storage compartment, the prepared fluidized solidified soil is stored therein, and the fluidized solidified soil can be prepared and output at the same time, thereby improving work efficiency.

[0006] The technical solution adopted by the present invention to solve the technical problem is: A fluidized solidified soil preparation device and backfilling method for foundation pit backfilling, comprising a transport vehicle, a water supply component, a curing agent storage compartment, a curing agent slurry preparation compartment, a crushing component and a preparation component are arranged above the transport vehicle, the water supply component is connected to the curing agent slurry preparation compartment and the preparation component through a pipeline, the curing agent storage compartment is connected to the curing agent slurry preparation compartment through a curing agent raw material conveying pipe, the crushing component is arranged above the preparation component, and the device disclosed in the present invention can prepare liquid solidified soil at the construction site, saving the transportation cost of raw materials and fluidized solidified soil, adding raw materials according to the on-site backfilling situation to avoid waste, and also comprising a screening component, the screening component is arranged above the transport vehicle and connected to the crushing component, although the screened soil material has met the standards of the "Technical Standards for the Application of Fluidized Solidified Soil", it still needs to be further crushed, one is to avoid the soil material having a high moisture content and sticking together, and the other is to further crush the soil material and improve the soil material standard, thereby improving the uniformity and stability of the fluidized solidified soil; the screening component comprises a screen, a support frame and a sliding plate connected in sequence up and down, and the bottom surface of the sliding plate is fixedly provided with an eccentric The vibration motor drives the screening component to vibrate through the eccentric vibrator to improve the screening rate and effect. It also includes a feeder, the horizontal section of which is connected to the discharge end of the screen. Large-sized soil and stones slide on the surface of the screen to the horizontal section of the feeder, and are sent to the rear of the transport vehicle through the feeder and transported away by workers. A mixing cabin and a product storage cabin are arranged inside the preparation component. The mixing cabin and the product storage cabin are connected by a pipeline. The mixing cabin includes a mixing cabin shell. A mixing roller is arranged at the center of the mixing cabin shell. The mixing roller The stirring blades below the drum gradually become shorter from bottom to top and then remain unchanged. The diameter of the lower end of the stirring drum is equal to the inner diameter of the outer shell of the stirring chamber. A motor is arranged inside the stirring drum, and a stirring drum shell is fixed outside the stirring drum. The bottom of the stirring drum shell is hollowed out. When the stirring drum rotates, it can transport the mixture at the bottom of the stirring chamber to the top, and the mixture then falls freely from the top. The hollow design below the stirring drum shell can make the mixture re-enter the stirring blades below the stirring drum, and this cycle is repeated to mix the mixture evenly and produce high-quality liquid solidified soil.

[0007] The soil excavated from the roadbed is mixed with various impurities. To prepare liquid solidified soil, only soil with a particle size of less than 50 mm is needed. The amount of excavated soil is large and the cost is low. There is no need to spend a lot of resources to grind large-grained soil and stones. Only strict screening is required.

[0008] Preferably, the water supply assembly is provided with a water supply pipe, on which a curing agent slurry preparation compartment water supply pipe and a mixing compartment water supply pipe are fixedly provided respectively, the curing agent slurry preparation compartment water supply pipe is connected to the curing agent slurry preparation compartment, and the mixing compartment water supply pipe is connected to a first feed port provided on the mixing compartment outer shell.

[0009] Preferably, the curing agent slurry preparation chamber further comprises a curing agent delivery pipeline, one end of which is connected to the curing agent slurry preparation chamber shell, and the other end of which is connected to a second feed port provided on the mixing chamber shell.

[0010] Preferably, the preparation component also includes a solidified soil conveying pipeline, on which a storage cabin conveying pipeline and a mixing cabin conveying pipeline are respectively arranged, the storage cabin conveying pipeline is connected to the product storage cabin, the mixing cabin conveying pipeline is connected to a second discharge port arranged on the mixing cabin outer shell, and a first discharge port is also arranged on the mixing cabin outer shell, and the first discharge port is connected to the product storage cabin through a pipeline. The liquid solidified soil prepared in the mixing cabin will be first stored in the product storage cabin, and then transported from the product storage cabin to the backfilling position. During this period, the mixing cabin can continue to prepare liquid solidified soil, repeating the cycle to improve work efficiency.

[0011] Preferably, the screening assembly also includes an auxiliary plate, which is fixed at the discharge end of the slide plate. The other end of the auxiliary plate is tilted downward, and qualified soil filtered from the screen will fall onto the slide plate and slide from the slide plate into the crushing assembly. The auxiliary plate can make the soil fall in the middle of the crushing assembly, preventing the soil from sliding onto the vehicle body, avoiding the trouble of cleaning later, and reducing labor intensity.

[0012] Preferably, a flip arc plate is arranged above the stirring drum shell, the flip arc plate is narrow at the top and wide at the bottom, and the diameter of the lower end of the flip arc plate is smaller than the diameter of the lower end of the stirring drum. The flip arc plate can prevent the mixture from falling back and affecting the stirring effect of the mixture, and can also make the mixture evenly dispersed between the stirring drum shell and the stirring chamber shell.

[0013] Preferably, a plurality of mutually perpendicularly staggered horizontal bars and vertical bars are fixedly arranged inside the support frame, and vertical bars are perpendicularly arranged at the intersection of the horizontal bars and the vertical bars. The upper ends of the vertical bars are in contact with the bottom surface of the screen, and the lower ends of the vertical bars are in contact with the top surface of the sliding plate to support the screen and prevent the screen from being sunken and deformed too much, thereby damaging the screen.

[0014] Preferably, a funnel is arranged below the crushing assembly, and the bottom of the funnel extends into the upper end of the mixing chamber shell, so that all the soil materials processed by the crushing assembly fall into the inside of the mixing chamber shell.

[0015] Preferably, the mesh size is 50 mm. The soil particle size specified in the Technical Standard for Application of Fluidized Solidified Soil T / SDSZ 8-2023 is less than or equal to 50 mm, which imposes strict requirements on screening to improve the uniformity and stability of the fluidized solidified soil and reduce the pressure of the crushing assembly.

[0016] A fluidized solidified soil foundation pit backfilling method comprises the following steps: S1. Treat the bottom of the foundation pit, clean up the debris, and replace the soft foundation according to the specifications; S2. The fluidized solidified soil needs to be poured in layers. The pouring thickness in conventional areas is ≤1.2m, and the pouring thickness in areas with complex structures is ≤0.8m. In addition, multi-point pouring and over-pouring are used in areas with complex structures. Multi-point pouring can effectively avoid the generation of holes. Holes are inevitable in areas with complex structures. Under the self-compacting effect of the fluidized solidified soil, the gas is discharged. Over-pouring can avoid the height difference on the upper surface. The pouring should follow the principle of pouring from deep to shallow and from far to near. S3. The outlet of the fluidized solidified soil conveying pipeline extends into the solidified soil or is close to the upper surface of the solidified soil, effectively preventing air from entering the solidified soil; S4. After pouring, scrape the surface before final setting, reserve a 2% to 3% drainage slope, and set drainage ditches according to the needs of the foundation pit location; S5. Cover with geotextile + plastic film after final setting, and maintain moisture retention for ≥ 7 days. When the ambient temperature is <5℃, add a thermal insulation quilt.

[0017] It should be noted that the device disclosed in the present invention can continuously prepare fluidized solidified soil at the backfilling site, and there is no need to worry about the problem of too long interval time for layered backfilling.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The device disclosed in the present invention filters large-size stones and soil blocks by setting a screening component with an aperture of 50 mm to obtain soil materials that meet the "Technical Standard for Application of Fluidized Solidified Soil" T / SDSZ 8-2023, avoiding complicated crushing processes, reducing costs and improving the uniformity and stability of the fluidized solidified soil; by setting a product storage compartment, the prepared fluidized solidified soil is stored therein, and the fluidized solidified soil can be prepared and output at the same time, thereby improving work efficiency and avoiding problems in the layered backfilling interval process.

[0019] 2. The device disclosed by the present invention is provided with a stirring drum, so that the mixture moves repeatedly from bottom to top, the mixture can be fully and evenly mixed, and the prepared liquid solidified soil has good uniformity and stability.

[0020] 3. The device disclosed in the present invention arranges an auxiliary plate at the lower end of the sliding plate, and the qualified soil filtered from the screen will fall onto the sliding plate and slide from the sliding plate into the crushing assembly. The auxiliary plate can make the soil fall in the middle of the crushing assembly, preventing the soil from sliding onto the vehicle body, avoiding the trouble of cleaning later, and reducing labor intensity.

[0021] 4. The device disclosed in the present invention arranges a flip arc plate above the mixing drum shell. The flip arc plate can prevent the mixture from falling back and affecting the mixing effect of the mixture, and can also make the mixture evenly dispersed between the mixing drum shell and the mixing chamber shell.

[0022] 5. The device disclosed in the present invention supports the screen by arranging horizontal bars, longitudinal bars and vertical bars inside the supporting frame, thereby preventing the screen from being sunken and deformed too much and damaging the screen, thereby improving the durability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the device disclosed in the present invention; Figure 2 This is a schematic diagram of the structure of the equipment carried on the transport vehicle of the device disclosed in the present invention; Figure 3 It is a schematic diagram of the structure of the screening component of the device disclosed in the present invention; Figure 4 It is a schematic diagram of a half-section structure of a screening component of the device disclosed in the present invention; Figure 5 This is an exploded view of the preparation components of the device disclosed in the present invention.

[0024] Among them: 1. Transport vehicle; 2. Water supply assembly; 21. Water supply pipe; 211. Water supply pipe for curing agent slurry preparation chamber; 212. Water supply pipe for mixing chamber; 3. Curing agent storage chamber; 31. Curing agent raw material delivery pipe; 4. Curing agent slurry preparation chamber; 41. Curing agent delivery pipeline; 5. Screening assembly; 51. Screen; 52. Support frame; 521. Crossbar; 522. Longitudinal bar; 523. Vertical bar; 53. Sliding plate; 54. Eccentric vibration motor ; 55. Feeder; 56. Auxiliary plate; 6. Crushing assembly; 7. Preparation assembly; 71. Mixing chamber; 711. Mixing chamber shell; 712. First discharge port; 713. First feed port; 714. Second feed port; 715. Second discharge port; 716. Mixing drum; 717. Mixing drum shell; 72. Product storage chamber; 73. Solidified soil conveying pipeline; 731. Storage chamber conveying pipeline; 732. Mixing chamber conveying pipeline. DETAILED DESCRIPTION

[0025] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0026] like Figure 1-Figure 5As shown, a fluidized solidified soil preparation device and backfilling method for foundation pit backfilling include a transport vehicle 1, a water supply component 2, a curing agent storage compartment 3, a curing agent slurry preparation compartment 4, a crushing component 6 and a preparation component 7 are arranged above the transport vehicle 1, the water supply component 2 is connected to the curing agent slurry preparation compartment 4 and the preparation component 7 through a pipeline, the curing agent storage compartment 3 is connected to the curing agent slurry preparation compartment 4 through a curing agent raw material conveying pipe 31, the crushing component 6 is arranged above the preparation component 7, and the device disclosed in the present invention can prepare liquid solidified soil at the construction site, saving the transportation cost of raw materials and fluidized solidified soil, adding raw materials according to the on-site backfilling situation to avoid waste, and also includes a screening component 5, the screening component 5 is arranged above the transport vehicle 1 and connected to the crushing component 6, although the sieved soil material has met the standards of the "Technical Standards for the Application of Fluidized Solidified Soil", it still needs to be further crushed, one is to avoid the soil material having a high moisture content and sticking together, and the other is to further crush the soil material and improve the soil material standard, thereby improving the uniformity and stability of the fluidized solidified soil; The screening assembly 5 comprises a screen 51, a support frame 52 and a sliding plate 53 connected in sequence from top to bottom. An eccentric vibration motor 54 is fixedly arranged on the bottom surface of the sliding plate 53. The eccentric vibration motor 54 drives the screening assembly 5 to vibrate, thereby improving the screening rate and effect. The screening assembly 5 also comprises a feeder 55. The horizontal section of the feeder 55 is connected to the discharge end of the screen 51. Large-sized soil blocks and stones slide on the upper surface of the screen 51 to the horizontal section of the feeder 55, and are sent to the rear of the transport vehicle 1 through the feeder 55, and are transported away by workers. A mixing chamber 71 and a product storage chamber 72 are arranged inside the preparation component 7, and the mixing chamber 71 and the product storage chamber 72 are connected by a pipeline. The mixing chamber 71 includes a mixing chamber shell 711, and a mixing drum 716 is arranged at the center position inside the mixing chamber shell 711. The mixing blades below the mixing drum 716 gradually become shorter from bottom to top and then remain unchanged. The diameter of the lower end of the mixing drum 716 is equal to the inner diameter of the mixing chamber shell 711. A motor is arranged inside the mixing drum 716, and a mixing drum shell 717 is fixed outside the mixing drum 716. The bottom of the mixing drum shell 717 is hollowed out. When the mixing drum 716 rotates, it can transport the mixture at the bottom of the mixing chamber 71 to the top, and the mixture then falls freely from the top. The hollow design below the mixing drum shell 717 can make the mixture re-enter the mixing blades below the mixing drum 716, and repeat the cycle to make the mixture evenly mixed to obtain high-quality liquid solidified soil.

[0027] like Figure 2As shown, the water supply assembly 2 is provided with a water supply pipe 21, on which a curing agent slurry preparation compartment water supply pipe 211 and a mixing compartment water supply pipe 212 are respectively fixedly provided, the curing agent slurry preparation compartment water supply pipe 211 is connected to the curing agent slurry preparation compartment 4, and the mixing compartment water supply pipe 212 is connected to a first feed port 713 provided on a mixing compartment shell 711; The curing agent slurry preparation chamber 4 further comprises a curing agent delivery pipeline 41 , one end of which is connected to the shell of the curing agent slurry preparation chamber 4 , and the other end of which is connected to a second feed port 714 provided on the mixing chamber shell 711 .

[0028] The preparation component 7 also includes a solidified soil conveying pipeline 73, on which a storage cabin conveying pipeline 731 and a mixing cabin conveying pipeline 732 are respectively arranged, the storage cabin conveying pipeline 731 is connected to the product storage cabin 72, the mixing cabin conveying pipeline 732 is connected to a second discharge port 715 arranged on the outer shell of the mixing cabin shell 711, and a first discharge port 712 is also arranged on the mixing cabin shell 711, and the first discharge port 712 is connected to the product storage cabin 72 through a pipeline, and the liquid solidified soil prepared in the mixing cabin 71 will be first stored in the product storage cabin 72, and then transported to the backfilling position by the product storage cabin 72, during which the mixing cabin 71 can continue to prepare liquid solidified soil, cyclically, thereby improving work efficiency.

[0029] like Figure 3 and Figure 4 As shown, the screening component 5 also includes an auxiliary plate 56, which is fixed at the discharge end of the slide plate 53. The other end of the auxiliary plate 56 is tilted downward, and the qualified soil filtered from the screen 51 will fall onto the slide plate, and slide from the slide plate 53 into the crushing component 6. The auxiliary plate 56 can make the soil fall in the middle of the crushing component 6, avoiding the soil from sliding onto the vehicle body, avoiding the trouble of cleaning later, and reducing labor intensity.

[0030] like Figure 5 As shown, a flip arc plate is arranged above the stirring drum shell 717. The flip arc plate is narrow at the top and wide at the bottom. The diameter of the lower end of the flip arc plate is smaller than the diameter of the lower end of the stirring drum 716. The flip arc plate can prevent the mixture from falling back and affecting the stirring effect of the mixture, and can also make the mixture evenly dispersed between the stirring drum shell 717 and the stirring chamber shell 711.

[0031] like Figure 4As shown, a plurality of mutually perpendicularly staggered horizontal bars 521 and vertical bars 522 are fixedly arranged inside the support frame 52, and a vertical bar 523 is vertically arranged at the intersection of the horizontal bars 521 and the vertical bars 522. The upper end of the vertical bar 523 contacts the bottom surface of the screen 51, and the lower end of the vertical bar 523 contacts the top surface of the sliding plate 53 to support the screen 51 and prevent the screen 51 from sinking and deforming too much, thereby damaging the screen 51.

[0032] A funnel is arranged below the crushing assembly 6 , and the bottom of the funnel extends into the upper end of the mixing chamber shell 711 , so that all the soil materials processed by the crushing assembly 6 fall into the inside of the mixing chamber shell 711 .

[0033] The aperture of the sieve 51 is 50 mm. The soil particle size specified in the Technical Standard for Application of Fluidized Solidified Soil T / SDSZ 8-2023 is less than or equal to 50 mm, which imposes strict requirements on screening, improves the uniformity and stability of the fluidized solidified soil, and reduces the pressure of the crushing component 6.

[0034] A fluidized solidified soil foundation pit backfilling method comprises the following steps: S1. Treat the bottom of the foundation pit, clean up the debris, and replace the soft foundation according to the specifications; S2. The fluidized solidified soil needs to be poured in layers. The pouring thickness in conventional areas is ≤1.2m, and the pouring thickness in areas with complex structures is ≤0.8m. In addition, multi-point pouring and over-pouring are used in areas with complex structures. Multi-point pouring can effectively avoid the generation of holes. Holes are inevitable in areas with complex structures. Under the self-compacting effect of the fluidized solidified soil, the gas is discharged. Over-pouring can avoid the height difference on the upper surface. The pouring should follow the principle of pouring from deep to shallow and from far to near. S3. The outlet of the fluidized solidified soil delivery pipe 73 extends into the solidified soil or is close to the upper surface of the solidified soil, effectively preventing air from entering the interior of the solidified soil; S4. After pouring, scrape the surface before final setting, reserve a 2% to 3% drainage slope, and set drainage ditches according to the needs of the foundation pit location; S5. Cover with geotextile + plastic film after final setting, and maintain moisture retention for ≥ 7 days. When the ambient temperature is <5℃, add a thermal insulation quilt.

[0035] The invention discloses a method for using the device: 1. Drive the transport vehicle 1 to the vicinity of the foundation pit to be backfilled. At this time, the miscellaneous soil excavated from the road is piled near the construction site; 2. Pre-operate the device, check the device status, and then fill the water supply component 2 and the curing agent storage compartment 3 with raw materials; 3. Operate the device and transport the soil to the screening assembly 5 by forklift or manual labor, and observe the large-size soil and stones discharged from the bottom of the feeder 55. When a certain amount is reached, transport it out of the construction site; 4. Always check the liquid solidified soil discharged from the solidified soil delivery pipeline 73, and adjust the mix ratio according to the test results. Because the moisture content of the miscellaneous soil at the construction site is uncertain, it is necessary to adjust the production mix ratio of the device at any time.

[0036] 5. Estimate the amount of liquid solidified soil required for the project, stop production before backfilling is completed, and discharge the liquid solidified soil in the product storage chamber 72 and the mixing chamber 71; 6. Clean the preparation component 7 and drive the transport vehicle 1 away from the site.

[0037] In the description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "vertical", "horizontal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the purpose of describing the present invention rather than requiring the present invention to be constructed or operated in a specific position, and therefore should not be construed as limiting the present invention. The terms "connected" and "connected" in the present invention should be understood in a broad sense, for example, it can be a connection or a detachable connection; it can be a direct connection or an indirect connection through an intermediate component. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0038] The above is the preferred operation mode of the present invention, and the description of the specific operation mode is only used to better understand the concept of the present invention. For ordinary technicians in this technical field, several improvements or equivalent substitutions can be made according to the principles of the present invention, and these improvements or equivalent substitutions are also considered to fall within the protection scope of the present invention.

Claims

1. A fluidized solidified soil preparation device for foundation pit backfilling, comprising a transport vehicle (1), a water supply component (2), a curing agent storage chamber (3), a curing agent slurry preparation chamber (4), a crushing component (6) and a preparation component (7) are arranged above the transport vehicle (1), the water supply component (2) is connected to the curing agent slurry preparation chamber (4) and the preparation component (7) through a pipeline, the curing agent storage chamber (3) is connected to the curing agent slurry preparation chamber (4) through a curing agent raw material delivery pipe (31), the crushing component (6) is arranged above the preparation component (7), and is characterized in that: It also includes a screening assembly (5), wherein the screening assembly (5) is arranged above the transport vehicle (1) and connected to the crushing assembly (6); The screening assembly (5) comprises a screen (51), a support frame (52) and a sliding plate (53) connected in sequence from top to bottom, an eccentric vibration motor (54) being fixedly arranged on the bottom surface of the sliding plate (53), and a feeder (55), wherein a horizontal section of the feeder (55) is connected to a discharge end of the screen (51); A stirring chamber (71) and a product storage chamber (72) are arranged inside the preparation component (7), and the stirring chamber (71) and the product storage chamber (72) are connected by a pipeline. The stirring chamber (71) comprises a stirring chamber shell (711), and a stirring roller (716) is arranged at the center position inside the stirring chamber shell (711). The stirring blades below the stirring roller (716) gradually become shorter from bottom to top and then remain unchanged. The diameter of the lower end of the stirring roller (716) is equal to the inner diameter of the stirring chamber shell (711). A motor is arranged inside the stirring roller (716), and a stirring roller shell (717) is fixed outside the stirring roller (716). The bottom of the stirring roller shell (717) is hollowed out.

2. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 1, characterized in that: The water supply assembly (2) is provided with a water supply pipe (21), on which a curing agent slurry preparation chamber water supply pipe (211) and a mixing chamber water supply pipe (212) are respectively fixedly provided, the curing agent slurry preparation chamber water supply pipe (211) is connected to the curing agent slurry preparation chamber (4), and the mixing chamber water supply pipe (212) is connected to a first feed port (713) provided on a mixing chamber shell (711).

3. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 2, characterized in that: The curing agent slurry preparation chamber (4) further comprises a curing agent delivery pipeline (41), one end of the curing agent delivery pipeline (41) being connected to the shell of the curing agent slurry preparation chamber (4), and the other end of the curing agent delivery pipeline (41) being connected to a second feed port (714) provided on the outer shell (711) of the stirring chamber.

4. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 3, characterized in that: The preparation assembly (7) further comprises a solidified soil conveying pipeline (73), on which a storage chamber conveying pipeline (731) and a mixing chamber conveying pipeline (732) are respectively arranged, the storage chamber conveying pipeline (731) is connected to the product storage chamber (72), the mixing chamber conveying pipeline (732) is connected to a second discharge port (715) arranged on the mixing chamber shell (711), and the mixing chamber shell (711) is also provided with a first discharge port (712), and the first discharge port (712) is connected to the product storage chamber (72) via a pipeline.

5. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 1, characterized in that: The screening assembly (5) further comprises an auxiliary plate (56), wherein the auxiliary plate (56) is fixed to the discharge end of the sliding plate (53), and the other end of the auxiliary plate (56) is arranged to be inclined downward.

6. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 1, characterized in that: A flip arc plate is arranged above the stirring drum shell (717), the flip arc plate is narrow at the top and wide at the bottom, and the diameter of the lower end of the flip arc plate is smaller than the diameter of the lower end of the stirring drum (716).

7. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 1, characterized in that: A plurality of mutually perpendicularly staggered horizontal bars (521) and vertical bars (522) are fixedly arranged inside the support frame (52); vertical bars (523) are arranged perpendicularly at the intersection of the horizontal bars (521) and the vertical bars (522); the upper ends of the vertical bars (523) are in contact with the bottom surface of the screen (51), and the lower ends of the vertical bars (523) are in contact with the top surface of the sliding plate (53).

8. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 1, characterized in that: A funnel is provided below the pulverizing assembly (6), and the bottom of the funnel extends into the upper end of the mixing chamber shell (711).

9. The fluidized solidified soil preparation device for foundation pit backfilling according to claim 1, characterized in that: The sieve (51) has a hole diameter of 50 mm.

10. A method for backfilling a foundation pit with fluidized solidified soil, characterized in that: The following steps are involved: S1. Treat the bottom of the foundation pit, clean up the debris, and replace the soft foundation according to the specifications; S2. Fluidized solidified soil needs to be poured in layers. The pouring thickness in conventional areas is ≤1.2m, and the pouring thickness in complex structural areas is ≤0.8m. In addition, point pouring and over-pouring are adopted in complex structural areas. The pouring should follow the principle of pouring from deep to shallow and from far to near. S3. The outlet of the fluidized solidified soil conveying pipeline (73) extends into the solidified soil or is close to the upper surface of the solidified soil; S4. After pouring, scrape the surface before final setting, reserve a 2% to 3% drainage slope, and set drainage ditches according to the needs of the foundation pit location; S5. Cover with geotextile + plastic film after final setting, and maintain moisture retention for ≥ 7 days. When the ambient temperature is <5℃, add a thermal insulation quilt.

Images