Recyclable integral pit bottom grouting open caisson
By designing a recyclable integral pit bottom grouting caisson, the problem of difficulty in blocking the pit bottom surge accident is solved, and fast and reliable surge handling and safety guarantee is achieved, while reducing costs.
Patent Information
- Application Number
- CN202421093366.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-20
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2034-05-20
AI Technical Summary
When excavating foundation pits in formations containing pressure-bearing water, it is often difficult to effectively seal the bottom surge accidents, and the existing technology is difficult to deal with oblique or curved surge paths, and the grouting pressure is difficult to resist, which is easy to cause sealing failure.
A recyclable integral pit bottom grouting caisson is designed. The caisson sleeve is located on the periphery of the decompression well. Through the integral structure formed by four sides, a cavity is left inside for passing through the decompression well. A grouting hole and an inclined grouting tube are provided on the side to inject cement slurry into the protrusion and form a reinforcement seal.
This technology can quickly and reliably handle surge accidents, reduce the impact on project quality and construction progress, provide higher safety guarantees for projects, and reduce material and construction costs due to the recyclable caisson.
Smart Images
Figure CN222594927U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field of building construction, and in particular relates to a recyclable integral pit bottom grouting caisson. Background Art
[0002] my country's urbanization process is advancing rapidly, and the development of underground space has entered a new stage. The number of deep foundation pit projects is increasing. When excavating foundation pits in strata containing pressurized water, if the gravity of the soil covering the bottom of the pit is not enough to resist the pressure of the pressurized water, or there are unfilled exploration holes and drainage holes on the site, sudden surge accidents may be induced. Such accidents occur suddenly and are difficult to handle. Not only may they cause economic losses to the project, but if there is serious soil and water loss at the bottom of the pit, they may also affect the surrounding environment and even damage surrounding building structures.
[0003] At present, the common treatment methods for sudden surge accidents are mainly to use pressure relief wells for water diversion and grouting for plugging. (1) The principle of pressure relief well diversion is to vertically drill a pressure relief well at the sudden surge point, drill the bottom of the well into the confined water layer, guide the confined water to rise from the well, and then construct the outer bottom plate. After the underground structure is completed and the anti-floating requirements are met, the well is sealed. This method is more effective for vertical sudden surge paths. Once an oblique or curved sudden surge path is encountered, the well wall will cut off the sudden surge path, and the confined water will surge along the well wall, forming a new sudden surge point outside the confined well, resulting in water diversion failure. (2) Grouting plugging is to inject grouting pressure into the sudden surge point to plug the sudden surge path. However, the confined water head is often high and the pressure is often large. The grouting pressure is difficult to compete with it, which can easily cause plugging failure. Even if the upper end of the sudden surge path is successfully plugged, the sudden surge path is prone to deflection under the pressure of the confined water, forming a new sudden surge point next to the original sudden surge point.
[0004] Therefore, it is urgent to develop a pit bottom grouting caisson for solving the problem of sudden surge blocking at the pit bottom. Utility Model Content
[0005] The utility model aims to solve the problem of blocking sudden surges at the pit bottom and provide a recyclable integral pit bottom grouting caisson.
[0006] The specific technical solutions adopted by this utility model are as follows:
[0007] The utility model provides a recyclable integral pit bottom grouting caisson, which is sleeved outside a pressure relief well at the periphery of a sudden surge that needs to be blocked; the pit bottom grouting caisson is composed of four sides forming a whole, and a cavity is left inside the caisson for passing through the pressure relief well;
[0008] Each side of the pit bottom grouting caisson includes a first side plate, a second side plate and a third side plate from the outside to the inside; the first side plate and the third side plate are equal in length and are arranged along the longitudinal direction of the pit bottom grouting caisson; a plurality of grouting holes for grouting are reserved between the first side plate and the third side plate, and the second side plate connecting the first side plate and the third side plate is arranged at the remaining position; the second side plate limits the spatial size of each column of grouting holes to prevent slurry from leaking out; the outlet of each column of grouting holes is provided with a grouting pipe inclined downward; the outlet direction of the grouting pipe is toward the surge inside the pressure relief well.
[0009] Preferably, the first side plate, the second side plate and the third side plate are all made of steel plates and are welded into a whole.
[0010] Furthermore, the thickness of the steel plate is 14 to 25 mm.
[0011] Preferably, two rows of grouting holes are provided on each side of the pit bottom grouting caisson; and three grouting pipes are arranged in sequence in the longitudinal direction in each row of grouting holes.
[0012] Preferably, the outer diameter of the grouting pipe is 48 mm, and the cross-sectional size of the grouting hole is 30 mm×14 mm.
[0013] Preferably, the grouting pipe is a steel pipe.
[0014] Preferably, the first side plate, the second side plate, the third side plate and the grouting pipe are fixedly connected by welding.
[0015] Preferably, the angle between the grouting pipe and the side of the pit bottom grouting caisson is 25° to 35°.
[0016] Preferably, the outlet of the grouting pipe is provided with a tape for temporary sealing, and the tape will be broken due to the grouting pressure during grouting.
[0017] Preferably, an inclined blade is provided at the bottom of the side of the pit bottom grouting caisson to facilitate pressing into the formation.
[0018] Compared with the prior art, the utility model has the following beneficial effects:
[0019] (1) The pit bottom grouting caisson provided by the utility model can be adapted to the pressure relief well. While releasing the pressure of the pressurized water, grouting is injected into the pit bottom to form an effective reinforcement body to block the sudden surge. This caisson can handle sudden surge accidents more quickly and reliably, reduce the adverse effects of sudden surge accidents on project quality and construction progress, provide higher safety guarantees for projects under construction, and ensure the smooth progress of the projects.
[0020] (2) The pit bottom grouting caisson provided by the utility model can also be recycled and reused, reducing material costs and construction costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 A plan view of a pit bottom grouting caisson provided for an embodiment;
[0022] Figure 2 for Figure 1 Middle AA section;
[0023] Figure 3 A top view of the connection between the grouting hole and the grouting pipe in the embodiment;
[0024] Figure 4 It is a side view of the connection between the grouting hole and the grouting pipe in the embodiment;
[0025] Figure 5 It is a schematic diagram of the arrangement of the pressure relief well in the embodiment;
[0026] Figure 6 It is a diagram of the grouting process of the sinking pit bottom in the embodiment;
[0027] Figure 7 This is a schematic diagram of the pit bottom grouting caisson in place in the embodiment;
[0028] Figure 8 Schematic diagram of a reinforcement body formed by grouting in the embodiment;
[0029] Fig. 9 It is a schematic diagram of the peripheral bottom plate arrangement of the pressure relief well in the embodiment;
[0030] Fig.10 This is a diagram of the process of pulling up the pit bottom and grouting the caisson in the embodiment;
[0031] Fig.11 This is a schematic diagram of the arrangement of the water stop plate in the embodiment;
[0032] Fig.12 This is a schematic diagram of the construction of the middle bottom plate in the embodiment;
[0033] Fig.13 A schematic diagram of sealing a well in an embodiment;
[0034] In the figure: pressure relief well 1, pit bottom grouting caisson 2, grouting hole 201, grouting pipe 202, first side plate 203, second side plate 204, third side plate 205, pit bottom 3, surge point 4, surge path 5, pressurized water layer 6, reinforcement body 7, water stop plate 8, bottom plate 9. DETAILED DESCRIPTION
[0035] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model. Therefore, the utility model is not limited by the specific embodiments disclosed below. The technical features in each embodiment of the utility model can be combined accordingly without conflicting with each other.
[0036] In the description of the present utility model, it should be understood that the terms "first" and "second" are only used for the purpose of distinguishing descriptions, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features.
[0037] like Figure 1 and Figure 2 As shown, as a preferred mode of the utility model, this embodiment provides a recyclable integral pit bottom grouting caisson. At present, when excavating a foundation pit in a stratum containing pressurized water, in case of a sudden surge accident, a method of vertically drilling a pressure relief well is usually adopted to guide the pressurized water to rise from the well, and then construct the outer bottom plate 9. The pit bottom grouting caisson 2 provided by the utility model is set on the pressure relief well 1 outside the sudden surge that needs to be blocked.
[0038] like Figure 1 As shown, the pit bottom grouting caisson 2 provided by the utility model is composed of four sides forming a whole, and a cavity is left inside for passing the pressure relief well 1. Figure 3 As shown, each side of the pit bottom grouting caisson 2 includes a first side plate 203, a second side plate 204 and a third side plate 205 from the outside to the inside.
[0039] In the pit bottom grouting caisson provided by the utility model, the first side plate 203 and the third side plate 205 are of equal length and are arranged in the longitudinal direction of the pit bottom grouting caisson 2; a grouting hole 201 for grouting is reserved between the first side plate 203 and the third side plate 205, and the second side plate 204 connecting the first side plate 203 and the third side plate 205 is arranged at the rest. The second side plate 204 defines the spatial size of each row of grouting holes 201 to prevent slurry from leaking out, as shown in the figure. Figure 4 In order to inject cement slurry to block the sudden surge, the outlet of each grouting hole 201 is provided with a grouting pipe 202 inclined downward; the outlet direction of the grouting pipe 202 is toward the sudden surge inside the pressure relief well 1.
[0040] Since the pit bottom grouting caisson 2 needs to sink from top to bottom into the stratum, this process will encounter certain resistance. Therefore, the bottom of the side of the pit bottom grouting caisson 2 is provided with an oblique blade that is convenient for pressing into the stratum. Furthermore, the grouting pipes 202 in the utility model are all made of steel pipes. The mechanical strength of the steel pipe is greater, which avoids damage to the grouting pipe during the sinking process. In addition, in order to further reduce the resistance of the sinking pit bottom grouting caisson 2, the angle between the grouting pipe 202 and the side of the pit bottom grouting caisson 2 is controlled within the range of 25° to 35°.
[0041] In the pit bottom grouting caisson provided by the utility model, the first side plate 203, the second side plate 204 and the third side plate 205 are all made of steel plates and are welded to form a whole. In order to control the thickness of the side of the pit bottom grouting caisson and reduce the sinking resistance, the first side plate 203, the second side plate 204 and the third side plate 205 in the utility model are all made of steel plates with a thickness ranging from 14 to 25 mm.
[0042] It should be noted that the spacing between the grouting holes 201 for grouting between the first side plate 203 and the third side plate 205 can be set according to specific working conditions. In the present utility model, the spacing between the first side plate 203 and the third side plate 205 is the thickness of a steel plate, and those skilled in the art can also add steel plates and adjust the spacing as needed.
[0043] In the pit bottom grouting caisson provided by the utility model, two rows of grouting holes 201 are arranged on each side of the pit bottom grouting caisson 2, and three grouting pipes 202 are arranged in sequence along the longitudinal direction in each row of grouting holes 201. However, the utility model does not specifically limit the number and arrangement of the grouting holes 201 and the grouting pipes 202, and those skilled in the art can make a choice according to the specific working conditions.
[0044] In the pit bottom grouting caisson provided by the utility model, the first side plate 203, the second side plate 204, the third side plate 205 and the grouting pipe 202 are fixedly connected by welding. The outlet of the grouting pipe 202 is provided with a tape for temporary closure, which will be broken by the grouting pressure during grouting.
[0045] Below, we take a pit bottom grouting caisson with a height of 5m, a length of 3.9m and a width of 3.9m as an example to introduce the various components and supporting construction methods.
[0046] like Figure 1 and Figure 2 As shown, positions of four pressure relief wells 1 are reserved at the four inner corners of the pit bottom grouting caisson 2. The diameter of the pressure relief well 1 is 800 mm and the height is 15 m.
[0047] The pit bottom grouting caisson 2 used in this embodiment is made of steel. Each side of the pit bottom grouting caisson 2 includes a first side plate 203, a second side plate 204 and a third side plate 205 from the outside to the inside. The three side plates are all made of 14mm thick steel plates overlapped and processed into a whole, so that each side of the pit bottom grouting caisson 2 is 42mm thick. An oblique blade is set at the bottom of the side of the pit bottom grouting caisson 2 to facilitate pressing the caisson into the formation.
[0048] Grouting holes 201 for grouting are reserved between the first side plate 203 and the third side plate 205. Two rows of grouting holes 201 are arranged in each side cavity section of the pit bottom grouting caisson 2 in the horizontal direction, and three grouting pipes 202 are arranged in sequence in each row of grouting holes 201 in the longitudinal direction.
[0049] Each grouting hole 201 outlet is connected to a grouting pipe 202. The angle between the grouting pipe and the inner wall is 30°. The grouting pipe 202 is divided into three layers, with 8 pipes in each layer, and 2 pipes are arranged in each direction of a single layer. The outlets of the grouting pipes 202 are all oriented toward the surge inside the pressure relief well 1. Below the grouting hole 201, the second side plate 204 is continuously arranged to prevent the slurry from leaking down.
[0050] Figure 3 and Figure 4 The schematic diagram of the connection node between the grouting hole and the grouting pipe is as follows: the cross section of the grouting hole 201 is rectangular, with a size of 30 mm × 14 mm. The outer diameter of the grouting pipe 202 is 48 mm. When the grouting caisson 2 is pressed into the bottom of the pit, the end of the grouting hole is temporarily sealed with tape. When grouting, the grouting pressure is increased to rely on the slurry to break through the tape for grouting.
[0051] The construction method of the above-mentioned recyclable integral pit bottom grouting caisson is as follows:
[0052] (1) Figure 5 As shown, a pressure relief well 1 is drilled around the surge point 4 so that the bottom of the pressure relief well 1 enters the confined water layer 6 to reduce the confined water pressure in the surge path 5 .
[0053] (2) Figure 6 As shown, the pit bottom grouting caisson 2 is set outside the pressure relief well 1 and is slowly and evenly pressed into the formation;
[0054] (3) Figure 7 and Figure 8 As shown, when the grouting caisson 2 at the bottom of the pit is in place, cement slurry is injected from the grouting hole 201 between the first side plate 203 and the third side plate 205, and the cement slurry flows out from the grouting pipe 202; after the cement slurry is bonded with the surrounding soil, a reinforcement body 7 is formed to block the sudden surge;
[0055] (4) Fig. 9As shown, clean the area around the pit bottom grouting caisson 2; after the earthwork is excavated to the pit bottom, the bottom plate 9 is first constructed around the pressure relief well 1 and the water stop plate 8 is pre-buried, leaving space for pulling up the pit bottom grouting caisson 2;
[0056] (5) Fig.10 As shown, the pit bottom grouting caisson 2 is slowly and evenly pulled up to leave the pressure relief well 1;
[0057] (6) Fig.11 As shown, a water stop plate 8 is welded on the outside of the pressure relief well 1, and the bottom plate 9 in the middle is constructed;
[0058] (7) Fig.12 and Fig.13 As shown, after the underground structure is constructed and meets the anti-floating requirements, the water level in the pressure relief well 1 is lowered to below the bottom plate 9, the pressure relief well 1 above the bottom plate 9 is cut off and sealed.
[0059] The utility model provides a pit bottom grouting caisson with a supporting pressure relief well, which is flexible to use. In actual use, the number of pressure relief wells in the pit bottom grouting caisson can be determined according to the surge volume and site construction conditions (1 to 4 are acceptable). If the surge volume at the pit bottom is small or the pressure relief well construction is inconvenient, the pressure relief well can be abandoned and the caisson can be directly pressed into the surge position for grouting reinforcement.
[0060] The above-described embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.
Claims
1. A recyclable integral pit bottom grouting caisson, characterized in that: The pit bottom grouting caisson (2) is sleeved outside the pressure relief well (1) at the periphery of the sudden surge that needs to be blocked; the pit bottom grouting caisson (2) is formed into a whole by four side surfaces, and a cavity is left inside the caisson for passing the pressure relief well (1); Each side of the pit bottom grouting caisson (2) comprises a first side plate (203), a second side plate (204) and a third side plate (205) from outside to inside; the first side plate (203) and the third side plate (205) are of equal length and are arranged along the longitudinal direction of the pit bottom grouting caisson (2); a plurality of grouting holes (201) for grouting are reserved between the first side plate (203) and the third side plate (205), and a second side plate (204) connecting the first side plate (203) and the third side plate (205) is arranged at the remaining positions; the second side plate (204) limits the spatial dimensions of each row of grouting holes (201) to prevent slurry from leaking out; the outlet of each row of grouting holes (201) is provided with a grouting pipe (202) inclined downward; the outlet direction of the grouting pipe (202) is toward the surge inside the pressure relief well (1).
2. The recyclable integral pit bottom grouting caisson according to claim 1 is characterized in that: The first side plate (203), the second side plate (204) and the third side plate (205) are all made of steel plates and are welded into a whole.
3. The recyclable integral pit bottom grouting caisson according to claim 2 is characterized in that: The thickness of the steel plate is 14 to 25 mm.
4. The recyclable integral pit bottom grouting caisson according to claim 1 is characterized in that: Each side of the pit bottom grouting caisson (2) is provided with two rows of grouting holes (201); each row of grouting holes (201) is provided with three grouting pipes (202) in sequence along the longitudinal direction.
5. The recyclable integral pit bottom grouting caisson according to claim 1 is characterized in that: The outer diameter of the grouting pipe (202) is 48 mm, and the cross-sectional dimensions of the grouting hole (201) are 30 mm×14 mm.
6. The recyclable integral pit bottom grouting caisson according to claim 1 is characterized in that: The grouting pipe (202) is made of a steel pipe.
7. The recyclable integral pit bottom grouting caisson according to claim 1 is characterized in that: The first side plate (203), the second side plate (204), the third side plate (205) and the grouting pipe (202) are all fixedly connected by welding.
8. The recyclable integral pit bottom grouting caisson according to claim 1 is characterized in that: The angle between the grouting pipe (202) and the side surface of the pit bottom grouting caisson (2) is 25° to 35°.
9. The recyclable integral pit bottom grouting caisson according to claim 1, characterized in that: The outlet of the grouting pipe (202) is provided with a tape for temporary sealing, and the tape will be broken due to the grouting pressure during grouting.
10. The recoverable integral pit bottom grouting caisson according to claim 1, characterized in that: The bottom of the side of the pit bottom grouting caisson (2) is provided with an oblique blade for easy pressing into the stratum.