A ground surface settlement prevention and control device and structure based on mold bag grouting

Abstract

The application discloses a ground surface settlement prevention and control device based on mold bag grouting and a prevention and control structure. The prevention and control device comprises a main grouting pipe, the outer periphery of the main grouting pipe is provided with a geotechnical mold bag, and the main grouting pipe is communicated with the geotechnical mold bag through a secondary grouting pipe. The prevention and control structure comprises a pile hole, and further comprises the prevention and control device, the main grouting pipe, the secondary grouting pipe and the geotechnical mold bag are located in the pile hole, backfill soil is arranged between the main grouting pipe and the inner wall of the pile hole, grout is poured in the main grouting pipe, the secondary grouting pipe and the geotechnical mold bag, the geotechnical mold bag is expanded and extruded to the soil body outward and forms the extruded soil body, and the main grouting pipe and the geotechnical mold bag jointly form a mold bag pile body. The application has the beneficial effects that the grouting pipe is arranged underground, the inflatable mold bag is arranged at the predetermined position, the mold bag is directionally expanded after the grout is injected and uniformly extrudes the surrounding soil body, so that the soil body is actively compacted, and the rigidity and integrity of the foundation are significantly improved.

Description

Technical Field

[0001] This application belongs to the field of surface construction technology, specifically relating to a surface settlement control method based on geotextile bag grouting, which achieves surface settlement control through grouting reinforcement. Background Technology

[0002] With the continuous development of urban construction, surface settlement is a common problem during the construction of subway tunnels and other projects. This disturbance of the underground soil disrupts the original stress balance, leading to surface settlement. If settlement is not properly controlled, it can endanger the safety of surface buildings, roads, pipelines, and other municipal facilities, causing serious economic losses. Therefore, how to effectively prevent and control surface settlement is a key issue of long-term concern. Currently, the commonly used technologies for preventing and controlling surface settlement mainly fall into two categories: grouting reinforcement and pile foundation reinforcement.

[0003] Traditional grouting technology mainly involves injecting cement grout or chemical grout into the soil through drilling, filling the soil pores to improve soil strength. However, it has the following shortcomings: First, it is difficult to control the diffusion range and flow direction of the grout, often resulting in disorderly grout loss and affecting the reinforcement effect; second, in strata with poor permeability, the grout is difficult to diffuse effectively, limiting the reinforcement effect; third, traditional grouting mainly relies on filling action, with insufficient compression effect on the soil.

[0004] Pile foundation reinforcement technologies, such as precast piles and bored piles, reduce settlement by transferring the load to the deep bearing layer. These technologies are highly reliable, but they also have drawbacks such as high construction costs, long construction periods, and significant environmental disturbance.

[0005] To overcome the shortcomings of traditional grouting methods, geotextile bag grouting technology has been proposed. This method involves delivering a geotextile bag to a predetermined underground location via a grouting pipe, then injecting grout into the bag, causing the grout to expand directionally under the constraint of the bag. Existing geotextile bag grouting is mostly used to form regular pile bodies, prevent grout loss, or perform segmented grouting (such as published patent CN119913890A), which can improve grouting efficiency and reduce costs.

[0006] However, existing methods for using geotextile bags for grouting have limitations. While they can serve to reinforce piles and prevent grout leakage, they fail to fully utilize the squeezing effect on the surrounding soil during the expansion of the geotextile bags, nor do they increase the overall integrity of the soil layer. Furthermore, current technology has not yet proposed a systematic arrangement method to enable the geotextile bags and the squeezed soil between them to work synergistically, thereby constructing a composite foundation with a group-pile effect and overall bearing capacity.

[0007] In summary, there is an urgent need in this field for a new technical solution that can inherit the controllability advantages of geotextile grouting and innovatively make full use of the pile group effect, thereby significantly improving the overall foundation stability and reducing the risk of surface settlement. Utility Model Content

[0008] The purpose of this application is to address the problems of uncontrollable grout diffusion, limited reinforcement effect, and inadequate utilization of the group pile effect in existing technologies. This application provides a surface settlement control device and structure based on geotextile bag grouting. By laying grouting pipes underground and setting up expansion geotextile bags, the geotextile bags expand during the grouting process and compress the soil, thereby forming a "group pile effect", avoiding uneven settlement and effectively controlling surface settlement.

[0009] The objective of this application is achieved through the following technical solution: A surface subsidence control device based on geotextile bag grouting includes a main grouting pipe, with a geotextile bag provided around the outer periphery of the main grouting pipe, and the main grouting pipe is connected to the geotextile bag through a secondary grouting pipe.

[0010] Furthermore, at least two sections of geotextile formwork bags are arranged along the upper and lower edges of the main grouting pipe.

[0011] Furthermore, the geotextile bag includes an inner pressure-bearing permeable layer and an outer impermeable isolation layer.

[0012] Furthermore, the pressure-bearing permeable layer is a permeable non-woven fabric, and the seepage-proof isolation layer is a tear-resistant nylon fabric.

[0013] Furthermore, the geotextile bag has a ring-shaped structure.

[0014] Furthermore, both the upper and lower ends of the geotextile bag are fixed to the main grouting pipe by mechanical clamps.

[0015] Furthermore, the top of the geotextile bag is connected to an exhaust pipe.

[0016] A surface settlement control structure based on geotextile grouting includes a pile hole and the aforementioned surface settlement control device based on geotextile grouting. The main grouting pipe, the secondary grouting pipe, and the geotextile bag are located inside the pile hole. Backfill soil is provided between the main grouting pipe and the inner wall of the pile hole. Grout is poured into the main grouting pipe, the secondary grouting pipe, and the geotextile bag. The geotextile bag expands outward to squeeze the soil and form the squeezed soil. The main grouting pipe and the geotextile bag together form a geotextile pile.

[0017] Furthermore, the pile holes are arranged in a group pile configuration, with the molded bag piles and the compressed soil forming an integral composite foundation.

[0018] Furthermore, the pile group arrangement adopts a grid-like layout with intersecting horizontal and vertical lines.

[0019] The beneficial effects of this application are: (1) By laying grouting pipes underground and installing expandable mold bags at their predetermined positions, the mold bags expand in a directional manner after the grout is injected, and the surrounding soil is uniformly squeezed, thereby achieving active compaction of the soil and significantly improving the rigidity and integrity of the foundation.

[0020] (2) The geotextile bag structure can effectively constrain the grout, prevent its disorderly diffusion and loss, and improve the utilization rate of grouting. After multiple geotextile bags are arranged in a regular manner, they interact with each other to form a composite foundation structure similar to a pile group, which further enhances the overall deformation resistance and realizes the active prevention and control of surface settlement.

[0021] (3) The construction process of the geotextile bag is simple and highly adaptable, and has good prospects for engineering application.

[0022] The aforementioned main solution and its various further alternatives can be freely combined to form multiple solutions, all of which are solutions that can be adopted and claimed in this application; furthermore, the (non-conflicting alternatives) can also be freely combined with each other and with other alternatives. Those skilled in the art, after understanding this solution, will realize from the prior art and common general knowledge that there are many combinations, all of which are technical solutions to be protected in this application, and will not be exhaustively listed here. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of this application.

[0024] Figure 2 This is a schematic diagram illustrating the effect of the mold bag in this application.

[0025] Figure 3 This is a schematic diagram of the planar layout of the molded bag in this application.

[0026] In the diagram: 1-Ground surface, 2-Main grouting pipe, 3-Mechanical clamp, 4-Secondary grouting pipe, 5-Confined permeable layer, 6-Squeezed soil, 7-Imperible isolation layer, 8-Exhaust pipe, 9-Geotextile bag, 10-Grouting, 11-Pile hole, 12-Geotextile bag influence area. Detailed Implementation

[0027] The present application will be further described below with reference to specific embodiments and accompanying drawings.

[0028] Example 1 refer to Figures 1-3 As shown, a surface settlement control device based on geotextile bag grouting includes a main grouting pipe 2, a mechanical clamp 3, a secondary grouting pipe 4, an exhaust pipe 8, and a geotextile bag 9 (including a pressure-bearing permeable layer 5 and an anti-seepage isolation layer 7).

[0029] The main grouting pipe 2 is a steel pipe or composite material pipe, with several grout outlets along its depth direction on its pipe wall. Grout is injected through the main grouting pipe 2 to form a vertical pile structure. The main grouting pipe 2 is connected to the geotextile bag 9 through the secondary grouting pipe 4, meaning that the grout injected into the main grouting pipe 2 can enter the geotextile bag 9 through the secondary grouting pipe 4.

[0030] A geotextile bag 9 is installed around the outer periphery of the main grouting pipe 2. Grout is injected into the geotextile bag 9 to pressurize and expand it, thereby squeezing the soil outward. Under the pressure of the grout, the geotextile bag overcomes the resistance of the surrounding soil and produces radially uniform expansion. During the expansion process, the geotextile bag exerts a radial squeezing effect on the surrounding soil, reducing the void ratio of the soil, increasing the density of the soil, and thus increasing the integrity of the foundation.

[0031] At least two sections of geotextile formwork bags 9 are arranged along the upper and lower edges of the main grouting pipe 2 to ensure the uniformity and stability of the squeezing effect. The upper formwork bags are arranged 0.5m away from the bottom layer of the key structure.

[0032] The geotextile formwork 9 comprises an inner pressure-bearing permeable layer 5 and an outer impermeable isolation layer 7, which maintains stability during high-pressure grouting. Grout 10 (water and cement) enters the geotextile formwork 9 and seeps out from the pressure-bearing permeable layer 5, forming a cementing layer between the pressure-bearing permeable layer 5 and the impermeable isolation layer 7. This cementing layer is used to form a bond between the geotextile formwork and the soil during minor grout seepage during grouting, enhancing the bonding effect between the geotextile formwork and the soil. Preferably, the pressure-bearing permeable layer 5 is made of permeable non-woven fabric, and the impermeable isolation layer 7 is made of tear-resistant nylon fabric.

[0033] The geotextile formwork bag 9 is ring-shaped, allowing it to be fitted and installed on the main grouting pipe 2. The ring shape is similar to a tire-shaped ring (or a donut shape). Both the upper and lower ends of the geotextile formwork bag 9 are fixed to the main grouting pipe 2 by mechanical clamps 3, and are used in conjunction with rubber sealing rings to improve sealing performance.

[0034] The top of the geotextile formwork bag 9 is connected to the exhaust pipe 8. An exhaust pipe is installed outside the formwork bag, which is close to the outer wall of the formwork bag, made of polyethylene material, and fixed with plastic strips to release the air present in the formwork bag during the initial stage of grouting.

[0035] Example 2 A surface settlement control structure based on geotextile bag grouting includes pile holes 11, backfill soil and grout 10, and also includes the surface settlement control device based on geotextile bag grouting of Example 1, wherein the pile holes 11 are opened on the ground surface 1.

[0036] The main grouting pipe 2, the secondary grouting pipe 4, and the geotextile bag 9 are located inside the pile hole 11. Backfill soil is provided between the main grouting pipe 2 and the inner wall of the pile hole 11. The gap between the pile hole and the main grouting pipe is filled with undisturbed soil and compacted in layers to restore the original stress state of the soil around the hole.

[0037] Grout 10 is poured into the main grouting pipe 2, the secondary grouting pipe 4 and the geotextile formwork bag 9. The grout 10 is used to form the pile structure in the main grouting pipe 2 and to expand the geotextile formwork bag 9 to squeeze the soil outward. The geotextile formwork bag 9 expands outward to squeeze the soil and form the squeezed soil 6. The main grouting pipe 2 and the geotextile formwork bag 9 together form the geotextile bag pile.

[0038] The pile holes 11 employ a group pile arrangement, with the piles arranged in a crisscrossing grid pattern. The manhole bags and the compressed soil 6 together form an integral composite foundation. Throughout the area to be reinforced, the main grouting pipes 2 are laid out in a rectangular grid pattern, with multiple manhole bags arranged regularly on the plane. After grouting expansion, the effective ranges between the manhole bags overlap, forming the manhole bag influence zone 12, which, together with the soil between the piles, forms a composite foundation. The numerous manhole bag piles and the compacted soil between the piles together constitute an integral composite foundation. This composite foundation works synergistically, increasing the soil stiffness and integrity, effectively dispersing the superstructure load, and reducing uneven settlement.

[0039] Through the above-described embodiments, this application can fully utilize the constraint and expansion compression effects of the geotextile bags, enabling the soil to achieve active compaction during the grouting process. Multiple geotextile bags work together to form a group pile effect, significantly improving the overall stability and anti-settlement capacity of the foundation, thereby achieving an economical, efficient, and reliable surface settlement prevention effect.

[0040] The foregoing basic examples and their further alternative examples can be freely combined to form multiple embodiments, all of which are embodiments that can be adopted and claimed in this application. In the scheme of this application, each alternative example can be arbitrarily combined with any other basic example and alternative example.

[0041] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A surface settlement control device based on geotextile bag grouting, comprising a main grouting pipe (2), characterized in that: The main grouting pipe (2) is provided with a geotextile bag (9) on its outer periphery, and the main grouting pipe (2) is connected to the geotextile bag (9) through a secondary grouting pipe (4).

2. The surface subsidence control device based on geotextile bag grouting according to claim 1, characterized in that: At least two sections of geotextile bags (9) are arranged along the upper and lower edges of the main grouting pipe (2).

3. The surface subsidence control device based on geotextile bag grouting according to claim 1 or 2, characterized in that: The geotextile bag (9) includes an inner pressure-bearing permeable layer (5) and an outer impermeable isolation layer (7).

4. The surface subsidence control device based on geotextile bag grouting according to claim 3, characterized in that: The pressure-bearing permeable layer (5) is a permeable non-woven fabric, and the seepage-proof isolation layer (7) is a tear-resistant nylon fabric.

5. The surface subsidence control device based on geotextile bag grouting according to claim 1, characterized in that: The geotextile bag (9) has a ring-shaped structure.

6. The surface subsidence control device based on geotextile bag grouting according to claim 1 or 5, characterized in that: The upper and lower ends of the geotextile bag (9) are fixed to the main grouting pipe (2) by mechanical clamps (3).

7. The surface subsidence control device based on geotextile bag grouting according to claim 1, characterized in that: The top of the geotextile bag (9) is connected to the exhaust pipe (8).

8. A surface settlement control structure based on geotextile bag grouting, comprising pile holes (11), characterized in that: It also includes the surface settlement control device based on geotextile grouting as described in any one of claims 1 to 7, wherein the main grouting pipe (2), the secondary grouting pipe (4) and the geotextile geotextile (9) are located inside the pile hole (11), backfill soil is provided between the main grouting pipe (2) and the inner wall of the pile hole (11), and grout (10) is poured into the main grouting pipe (2), the secondary grouting pipe (4) and the geotextile geotextile (9), the geotextile geotextile (9) expands outward to squeeze the soil and form the squeezed soil (6), and the main grouting pipe (2) and the geotextile geotextile (9) together form the geotextile pile body.

9. The surface settlement control structure based on geotextile bag grouting according to claim 8, characterized in that: The pile holes (11) are arranged in a group of piles, and the pile body and the compressed soil (6) together form an integral composite foundation.

10. The surface settlement control structure based on geotextile bag grouting according to claim 9, characterized in that: The pile group arrangement adopts a grid-like layout with intersecting horizontal and vertical lines.

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