WO2021243995A1

WO2021243995A1 - Deep foundation pit retaining wall structure and construction method for underground space structure

Info

Publication number: WO2021243995A1
Application number: PCT/CN2020/134187
Authority: WO
Inventors: 刘献刚; 刘斌; 胡余祥; 付辉
Original assignee: 江西基业科技集团有限公司
Priority date: 2020-06-02
Filing date: 2020-12-07
Publication date: 2021-12-09
Also published as: CN111851512A

Abstract

A deep foundation pit retaining wall structure, comprising a barrel-shaped retaining wall body (1), wherein a vertically penetrating water pipe (2) is cast inside the barrel-shaped retaining wall body (1), and the water pipe (2) is provided with a water outlet (3) located at the lower end face of the barrel-shaped retaining wall body (1) and a water inlet (4) located at the upper end face of the barrel-shaped retaining wall body (1). According to the deep foundation pit retaining wall structure, water can be injected, by means of the water pipe (2), into a soil body located at the lower end face of the barrel-shaped retaining wall body (1) so as to soften the soil body, thereby achieving the aim of reducing the end resistance of the barrel-shaped retaining wall body (1) so as to facilitate the sinking of the barrel-shaped retaining wall body (1); furthermore, a soil body located below the lower end face can be scoured by injecting a high-pressure water flow, so as to make the barrel-shaped retaining wall body (1) sink via gravity; and finally, the aims of reducing construction procedures, reducing construction noise, shortening the construction period and thus reducing pollution to the surrounding environment can be achieved.

Description

Construction method of retaining wall structure of deep foundation pit and underground space structure

Technical field

The invention relates to a construction method for a deep foundation pit retaining wall structure and an underground space structure.

Background technique

The construction of underground buildings is too difficult and the cost is too high, especially when it involves soft soil foundation, the proportion of "foundation support" works is too large, and the "support cost" is often higher than the cost of the main building. In addition, the complex construction of underground projects leads to multiple procedures and difficult connections. The required construction period is too long, and the surrounding environment is too large, such as noise, vibration, exhaust gas, mud, etc., especially in densely populated areas. In the prior art, when supporting deep foundation pits, the retaining wall is mainly formed by piling. For example, Chinese patent document CN108708382A discloses a continuous retaining wall for deep foundation pits, in which the continuous occlusal part consists of at least one layer The piles are continuously occluded with each other and are arranged annularly around the foundation pit; it also includes a water blocking component, which is inserted longitudinally at the occlusion of at least two adjacently arranged piles to prevent groundwater from flowing from the foundation of the continuous occluding part. The outside of the pit penetrates into the inside of the foundation pit; the water blocking component is channel steel or steel plate. With the above structure, the water blocking component can effectively prevent groundwater from penetrating into the inside of the foundation pit from the occlusion of two adjacent piles, thereby improving the water-stopping capacity of the continuous retaining wall of the deep foundation pit. Chinese Patent Document CN209308039U discloses a deep foundation pit underground space structure, which is characterized in that it includes: a foundation pit, the foundation pit is in the shape of a barrel; several cement-soil piles are arranged annularly along the inner wall of the foundation pit, and Are interlocked together to form a closed retaining wall; a number of internal support ring beams are fixedly arranged along the inner wall of the retaining wall to form a support for the retaining wall from the inside of the foundation pit to the soil, wherein the The spacing of the inner support ring beams gradually decreases from the top to the bottom of the foundation pit. The above two kinds of retaining walls for foundation pits are the two main retaining wall forms in the current existing technology, and they are all constructed by means of piling.

Although the above two retaining walls can be driven to the design depth according to the construction requirements, the piling construction itself will cause more construction procedures, greater construction noise, longer construction period, and greater pollution to the surrounding environment. shortcoming.

Summary of the invention

Therefore, the technical problem to be solved by the present invention is how to provide a deep foundation pit retaining wall structure and underground space with fewer construction procedures, less construction noise, shorter construction period, and less pollution to the surrounding environment. Construction method.

The present invention provides a deep foundation pit retaining wall structure, comprising: a cylindrical retaining wall body, wherein a ground breaking structure is formed at the bottom of the cylindrical retaining wall body, and the cylindrical retaining wall body is suitable for passing through the breaking soil The structure cooperates with its own gravity to achieve downward breaking and sinking; the cylindrical retaining wall body has a water pipe that penetrates from top to bottom, and the water pipe has a water outlet located on the lower end surface of the cylindrical retaining wall body, and The water inlet on the upper end surface of the cylindrical retaining wall body.

In the above-mentioned deep foundation pit retaining wall structure, the cylindrical retaining wall body includes: a first cylindrical body and a second cylindrical body poured together up and down; and the water pipe includes a first water pipe and a second water pipe; The water outlet is a first water outlet of the first water pipe located on the lower end surface of the first cylinder, and the first water pipe has a first water inlet located on the upper end surface of the first cylinder; the inlet The water outlet is a second water inlet of the second water pipe located on the upper end surface of the second cylinder, and the second water pipe has a second water outlet located on the lower end surface of the second cylinder; wherein, the first The first water inlet of the water pipe is communicated with the second water outlet of the second water pipe.

The above-mentioned self-sunken deep foundation pit retaining wall structure further includes a third water pipe poured into the cylindrical retaining wall body and communicating with the outside at the outer side wall of the cylindrical retaining wall body. The third water pipe communicates with the second water inlet.

In the above self-sunken deep foundation pit retaining wall structure, the cylindrical retaining wall body is an iron ore gravel concrete wall.

The above-mentioned self-sunken deep foundation pit retaining wall structure further includes a through grouting cast in the cylindrical retaining wall body and located between the upper end surface and the outer end surface of the cylindrical retaining wall body Tube.

In the above self-sunken deep foundation pit retaining wall structure, the grouting pipe is a cross grouting pipe, and each cross grouting pipe is provided with a cross grouting pipe, wherein the cross grouting pipe There is a horizontal pipe part penetrating the inner and outer side walls of the cylindrical retaining wall body transversely, and a vertical pipe part extending vertically inside the cylindrical retaining wall body.

In the above self-sunken deep foundation pit retaining wall structure, the water pipe and the grouting pipe are the same pipe.

The invention also provides a construction method of an underground space, which includes the following steps:

a. Shallow foundation treatment;

b. Install the first phantom;

Among them, it also includes:

c. Install steel bars and a first water pipe in the first mold, and pour concrete in the first mold to make a first cylinder; the bottom of the first cylinder is formed with a ground breaking structure; the first A water pipe having a first water outlet located on the lower end surface of the first cylinder body and a first water inlet located on the upper end surface of the first cylinder body;

d. Excavate and transport the soil from the inside of the first cylinder, so that the ground breaking structure and the first cylinder cooperate with gravity to achieve downward breaking of the soil, and pass through the first water pipe of the first The water inlet performs high-pressure water injection into the first cylinder, so that the high-pressure water jet ejected from the first water outlet will flush the soil at the lower end of the first cylinder into the first cylinder, thereby causing the The first cylinder body sinks under the action of its own gravity.

The construction method of the underground space mentioned above, after the step d, further includes the following steps: e. After the first cylinder sinks to a predetermined depth, a second mold is installed above the first cylinder, Install steel bars and a second water pipe in the second mold, connect the second water pipe with the first water pipe, and pour concrete in the second mold to make a second cylinder, wherein the The second water pipe has a second water inlet located on the upper end surface of the second cylinder; f. excavate soil from the inside of the first cylinder and the second cylinder, and pass through the first cylinder The second water inlet of the second water pipe performs high-pressure water injection inward, so that the high-pressure water jet ejected from the first water outlet will wash the soil at the lower end of the first cylinder into the first cylinder, In turn, the first cylinder and the second cylinder are caused to sink under the action of their own gravity to a predetermined depth.

The construction method of the above underground space, wherein, in the above step c and/or step e, it further includes installing a third water pipe, wherein the third water pipe communicates with the outside at the outer side wall of the first cylinder, And communicate with the second water inlet.

In the above construction method of the underground space, a plurality of the first water pipes are evenly arranged in the circumferential direction inside the first cylinder.

The construction method of the above underground space further includes the steps of adjusting the speed, depth and verticality of the sinking of the cylinder by controlling the excavation rate and adjusting the flow rate and pressure of the high-pressure water flow.

The construction method of the above underground space, which further includes, after sinking to a predetermined depth, according to the requirements of the strength or buoyancy of the base, press the concrete grout into the base through the first water pipe and the second water pipe, or to A pile or an anchor rod is added to the base to reinforce the anti-buoyancy force of the base.

The construction method of the above underground space is characterized in that the concrete includes iron ore sand.

The construction method of the above underground space, wherein, in the above step c, it further includes the step of pouring a through grouting pipe in the first cylinder and located between the upper end surface and the outer end surface of the first cylinder .

In the construction method of the above underground space, the grouting pipe is a cross grouting pipe, and each cross grouting pipe is provided with a cross grouting pipe, and the first mold body includes an inner formwork and an outer formwork. The cross grouting pipe has a horizontal pipe part penetrating the inner formwork and the outer formwork transversely, and a vertical pipe part extending vertically inside the first cylinder; the transverse pipe part of the cross grouting pipe Limiting parts are arranged at both ends of the pipe to limit the width of the lateral interval between the inner template and the outer template.

The above-mentioned technical solution of the present invention has the following technical effects:

1. A deep foundation pit retaining wall structure disclosed in an embodiment of the present invention includes: a cylindrical retaining wall body, wherein the bottom of the cylindrical retaining wall body is formed with a ground breaking structure, and the cylindrical retaining wall body is suitable for The ground breaking and sinking are realized through the combination of the ground breaking structure and its own gravity; the cylindrical retaining wall body is poured with a water pipe running through from top to bottom, and the water pipe has an outlet located on the lower end surface of the cylindrical retaining wall body. A water inlet and a water inlet located on the upper end surface of the cylindrical retaining wall body. Through the above design, on the one hand, water can be injected into the soil at the lower end of the cylindrical retaining wall body through a water pipe to soften the soil, thereby achieving the purpose of reducing the end resistance of the cylindrical retaining wall body, which is beneficial to the cylindrical retaining wall. The sinking of the main body, in addition, the softening of the soil can also facilitate the excavation and improve the construction progress; in addition, the soil below the lower end surface can be washed by injecting high-pressure water, so that the barrel-shaped retaining wall can rely on it. Gravity sinks; in this way, the goal of reducing construction procedures, reducing construction noise, shortening construction period, and reducing pollution to the surrounding environment can ultimately be achieved.

2. In the embodiment of the present invention, the deep foundation pit retaining wall structure further includes a first cylinder and a second cylinder that are poured together up and down; and the water pipe includes a first water pipe and a second water pipe; The water outlet is a first water outlet of the first water pipe located on the lower end surface of the first cylinder, and the first water pipe has a first water inlet located on the upper end surface of the first cylinder; the inlet The water outlet is a second water inlet of the second water pipe located on the upper end surface of the second cylinder, and the second water pipe has a second water outlet located on the lower end surface of the second cylinder; wherein, the first The first water inlet of the water pipe is communicated with the second water outlet of the second water pipe. In the above design, the entire deep foundation pit retaining wall structure is formed by butting at least two cylinders, which can avoid the use of a single structure to achieve insufficient depth, and cannot be adjusted according to the situation, or too high deep foundation pit retaining wall It may cause inconvenience to excavate the soil in the cylinder.

3. In the embodiment of the present invention, the deep foundation pit retaining wall structure further includes a third part that is cast in the cylindrical retaining wall body and communicates with the outside at the outer side wall of the cylindrical retaining wall body. A water pipe, the third water pipe is in communication with the second water inlet. By injecting water into the third water pipe, the water flows to the soil on the outer side wall of the cylindrical retaining wall to moisturize the soil, thereby reducing the friction resistance of the soil to the cylindrical retaining wall, which is beneficial to the cylindrical retaining wall. The sinking of the retaining wall body.

4. The barrel-shaped retaining wall body is an iron ore sandstone concrete wall. Since the material of the wall body is added with iron ore sandstone in addition to concrete, on the one hand, the weight of the barrel-shaped retaining wall body can be increased, which is beneficial to Sinking; on the other hand, because iron ore sandstone has good thermal conductivity, it can play a good passive energy-saving effect for collecting and using underground heat and cold energy, as well as for storage, recycling, and utilization.

5. The cylindrical retaining wall body further includes a through grouting pipe cast in the cylindrical retaining wall body and located between the upper end surface and the outer end surface of the cylindrical retaining wall body; The grout pipe can pass concrete grout into the soil of the base and the outer side wall after the cylindrical retaining wall body sinks to the final predetermined depth, so as to achieve the effects of water stop and reinforcement.

6. An underground space construction method disclosed in an embodiment of the present invention, wherein, a. shallow foundation treatment; b. installing a first mold body; wherein, it further includes: c. installing steel bars and a first mold in the first mold body A water pipe, and pour concrete in the first mold to make a first cylinder; the bottom of the first cylinder is formed with a ground breaking structure; the first water pipe has a lower end surface of the first cylinder The first water outlet, and the first water inlet located on the upper end surface of the first cylinder;

d. Excavate and transport the soil from the inside of the first cylinder, so that the ground breaking structure and the first cylinder cooperate with gravity to achieve downward breaking of the soil, and pass through the first water pipe of the first The water inlet performs high-pressure water injection into the first cylinder, so that the high-pressure water jet ejected from the first water outlet will flush the soil at the lower end of the first cylinder into the first cylinder, thereby causing the The first cylinder body sinks under the action of its own gravity. The above construction method can make full use of the high-pressure water flow to deal with the soil to achieve automatic sinking, and can be adjusted according to the sinking situation, such as the depth, verticality, and velocity of the first cylinder. The pressure and flow of the water flow are controlled and adjusted.

7. In step c and/or step e, further comprising installing a third water pipe, wherein the third water pipe communicates with the outside at the outer side wall of the first cylinder and communicates with the second water inlet . By injecting water into the third water pipe, the water flows to the soil on the outer side wall of the first cylinder to moisturize the soil, thereby reducing the friction resistance of the soil to the first cylinder, which can be beneficial to the first cylinder. Sinking.

Description of the drawings

In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the specific embodiments or the description of the prior art. Obviously, the appendix in the following description The drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative work, other drawings can be obtained based on these drawings.

Figure 1 is a schematic diagram of an embodiment of the deep foundation pit retaining wall structure of the present invention;

Figure 2 is a schematic diagram of another embodiment of the deep foundation pit retaining wall structure of the present invention;

Figure 3 is a schematic diagram of another embodiment of the deep foundation pit retaining wall structure of the present invention;

4 is a schematic diagram of a top view of one embodiment of the deep foundation pit retaining wall structure of the present invention;

Reference signs:

1-Cylinder retaining wall body; 100-breaking soil structure; 2-water pipe; 3-water outlet; 4-water inlet; 5-anchor rod; 6-bottom plate; 8-first cylinder; 9-second cylinder; 10-first water pipe; 11-second water pipe; 3'-first water outlet; 12-first water inlet; 4'-second water inlet; 13-second water outlet; 15-third water pipe.

detailed description

The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

Example 1

This embodiment provides a deep foundation pit retaining wall structure as one of the implementations

The method, as shown in FIG. 1, specifically includes: a cylindrical retaining wall body 1, wherein a ground breaking structure 100 is formed at the bottom of the cylindrical retaining wall body, and the cylindrical retaining wall body 1 is suitable for passing through the ground breaking structure 100 cooperates with its own gravity to achieve downward breaking and sinking; the cylindrical retaining wall body 1 is poured with a water pipe 2 that penetrates up and down, and the water pipe has a water outlet 3 located on the lower end surface of the cylindrical retaining wall body. , And the water inlet 4 located on the upper end surface of the cylindrical retaining wall body 1. In addition, it also includes a bottom plate 6 which is poured on the bottom of the deep foundation pit retaining wall structure and connected to the cylindrical retaining wall body. Body or anchor 5.

The ground breaking structure 2 is preferably a wedge-shaped edge structure formed at the bottom of the cylindrical retaining wall body 1 with a low outer and an inner height, or a blade foot structure, wherein the ground breaking structure 100 has a structure relative to the cylindrical retaining wall. The outer side wall of the main body of the main body 1 has an outwardly protruding structure, and the outer side of the protruding structure is vertically arranged or shaped, so that when the soil breaking structure 100 sinks with the aid of the gravity of the cylindrical retaining wall body 1, the soil The contact area between the body and the cylindrical retaining wall body 1 is reduced, especially in the soil with less water content (the case of foundation pit collapse is less), and the outer side of the protruding structure faces the cylindrical retaining wall body. 1 The frictional resistance is generated instead of mainly through the outer side wall of the main body of the cylindrical retaining wall 1, which is more conducive to the sinking of the cylindrical retaining wall body 1; if there is no such protruding structure, it will follow the downward The contact area between the outer side wall of the main body and the soil will continue to increase, resulting in an increasing frictional resistance, which is not conducive to sinking.

As another specific embodiment, as shown in FIG. 2, the cylindrical retaining wall body of the above-mentioned deep foundation pit retaining wall structure may further include: a first cylindrical body 8 and a second cylindrical body that are poured together up and down. 9; and the water pipe 2 includes a first water pipe 10 and a second water pipe 11; the water outlet 3 is the first water outlet 3'of the first water pipe 10 located on the lower end surface of the first cylinder 8, The first water pipe 10 has a first water inlet 12 located on the upper end of the first cylinder 8; the water inlet 4 is a second inlet of the second water pipe 11 located on the upper end of the second cylinder. Water port 4', the second water pipe 11 has a second water outlet 13 located on the lower end surface of the second cylinder 9; wherein, the first water inlet 12 and the second water pipe of the first water pipe 8 The second water outlet 13 of 11 communicates with each other. As a further improved embodiment, the upper part of the second cylinder 9 may also include a third cylinder, the structure of which may be the same as that of the second cylinder, and the internal water pipe is connected to the water pipe of the second cylinder (here Not marked).

Further, it may also include a third water pipe 15 cast in the cylindrical retaining wall body and communicating with the outside at the outer side wall of the cylindrical retaining wall body, and the third water pipe is connected to the second inlet The nozzle 4'is connected. As a preferred embodiment, the cylindrical retaining wall body is an iron ore sandstone concrete wall.

As shown in FIG. 3, a plurality of the first water pipes 10 are evenly arranged in the inner circumferential direction of the first cylinder 8. In addition, as shown in Figure 4, the deep foundation pit retaining wall structure also includes a through grouting cast in the cylindrical retaining wall body and located between the upper end surface and the outer end surface of the cylindrical retaining wall body Tube. The grouting pipe may be a cross grouting pipe, and each cross grouting pipe is provided with a cross grouting pipe, wherein the cross grouting pipe has an inner wall penetrating the cylindrical retaining wall body transversely. The lateral pipes of the side and outer side walls, and the vertical pipes extending vertically inside the cylindrical retaining wall body.

In order to save materials used, the water pipe and the grouting pipe may also be the same pipe.

Example 2

a. Shallow foundation treatment;

b. Install the first phantom;

Among them, it also includes:

After the step d, it may further include the following steps: e. After the first cylinder body sinks to a predetermined depth, a second mold body is installed above the first cylinder body, and the second mold body is installed in the second mold body. Install steel bars and a second water pipe, connect the second water pipe with the first water pipe, and pour concrete in the second mold to make a second cylinder, wherein the second water pipe has a The second water inlet on the upper end of the second cylinder; f. excavate soil from the inside of the first cylinder and the second cylinder, and pass through the second water inlet of the second water pipe High-pressure water injection is carried out inward, so that the high-pressure water jet ejected from the first water outlet will flush the soil at the lower end of the first cylinder into the first cylinder, so that the first cylinder and the The second cylinder body sinks under the action of its own gravity to a predetermined depth.

As another embodiment, in the above step c and/or step e, it further includes installing a third water pipe, wherein the third water pipe communicates with the outside at the outer side wall of the first cylinder and is connected to the The second water inlet is connected.

In the process of digging and transporting the soil, the speed, depth and verticality of the sinking of the cylinder can be further adjusted by controlling the excavation rate and adjusting the flow rate and pressure of the high-pressure water flow.

After sinking to a predetermined depth, pour the bottom plate at the base, and according to the requirements of the strength or buoyancy of the bottom plate, press the concrete slurry into the base through the first water pipe and the second water pipe, or add piles on the bottom plate The body or anchor rod strengthens the buoyancy resistance of the substrate.

As yet another specific embodiment, the concrete may also include iron ore sand.

As another specific embodiment, the step c further includes the step of pouring a through grouting pipe in the first cylinder and located between the upper end surface and the outer end surface of the first cylinder.

As yet another specific embodiment, the grouting pipe may be a cross grouting pipe, and each cross grouting pipe is provided with a cross grouting pipe, and the first mold body includes an inner template and an outer template, wherein the The cross grouting pipe has a horizontal pipe part penetrating the inner formwork and the outer formwork transversely, and a vertical pipe part extending vertically inside the first cylinder; the horizontal pipe of the cross grouting pipe Limiting parts are arranged at both ends of the part to limit the width of the horizontal interval between the inner template and the outer template.

Obviously, the foregoing embodiments are merely examples for clear description, and are not intended to limit the implementation manners. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is unnecessary and impossible to list all the implementation methods here. The obvious changes or changes derived from this are still within the protection scope created by the present invention.

Claims

A self-sinking deep foundation pit retaining wall structure includes:

The barrel-shaped retaining wall body,

It is characterized by

A soil breaking structure is formed at the bottom of the cylindrical retaining wall body, and the cylindrical retaining wall body is adapted to realize downward soil breaking and sinking through the gravity cooperation of the soil breaking structure and the cylindrical retaining wall body;

The cylindrical retaining wall body is poured with a water pipe that penetrates from top to bottom, and the water pipe has a water outlet located on the lower end surface of the cylindrical retaining wall body and a water inlet located on the upper end surface of the cylindrical retaining wall body.
The self-sinking deep foundation pit retaining wall structure according to claim 1, wherein the cylindrical retaining wall body comprises:

The first cylinder and the second cylinder are poured together up and down; and the water pipe includes a first water pipe and a second water pipe;

The water outlet is a first water outlet of the first water pipe located on the lower end surface of the first cylinder, and the first water pipe has a first water inlet located on the upper end surface of the first cylinder;

The water inlet is a second water inlet of the second water pipe located on the upper end surface of the second cylinder, and the second water pipe has a second water outlet located on the lower end surface of the second cylinder;

Wherein, the first water inlet of the first water pipe is in communication with the second water outlet of the second water pipe.
The self-sinking deep foundation pit retaining wall structure according to claim 2, characterized in that:

It also includes a third water pipe cast in the cylindrical retaining wall body and communicating with the outside at the outer side wall of the cylindrical retaining wall body, and the third water pipe is in communication with the second water inlet.
The self-sinking deep foundation pit retaining wall structure according to claim 3, characterized in that:

The cylindrical retaining wall body is an iron ore sandstone concrete wall body.
The self-sinking deep foundation pit retaining wall structure according to any one of claims 1-4, characterized in that it further comprises pouring in the cylindrical retaining wall body and located on the upper part of the cylindrical retaining wall body. The through grouting pipe between the end face and the outer end face.
The self-sinking deep foundation pit retaining wall structure according to claim 5, wherein the grouting pipe is a cross grouting pipe, and each cross grouting pipe is provided with a cross grouting pipe, wherein: The cross grouting pipe has a horizontal pipe portion penetrating the inner and outer side walls of the cylindrical retaining wall body transversely, and a vertical pipe portion extending vertically inside the cylindrical retaining wall body.
The self-sinking deep foundation pit retaining wall structure according to claim 6, wherein the water pipe and the grouting pipe are the same pipe.
A construction method of underground space, including the following steps:

a. Shallow foundation treatment;

b. Install the first phantom;

It is characterized in that it also includes:

c. Install steel bars and a first water pipe in the first mold, and pour concrete in the first mold to make a first cylinder; the bottom of the first cylinder is formed with a ground breaking structure; the first A water pipe having a first water outlet located on the lower end surface of the first cylinder body, and a first water inlet located on the upper end surface of the first cylinder body;

d. Excavate and transport the soil from the inside of the first cylinder, so that the ground breaking structure and the first cylinder cooperate with gravity to achieve downward breaking of the soil, and pass through the first water pipe of the first The water inlet performs high-pressure water injection into the first cylinder, so that the high-pressure water jet ejected from the first water outlet will flush the soil at the lower end of the first cylinder into the first cylinder, thereby causing the The first cylinder body sinks under the action of its own gravity.
The construction method of the underground space according to claim 8, further comprising the following steps after the step d:

e. After the first cylinder sinks to a predetermined depth, install a second mold above the first cylinder, install steel bars and a second water pipe in the second mold, and connect the second water pipe Communicating with the first water pipe and pouring concrete in the second mold to make a second cylinder, wherein the second water pipe has a second water inlet located on the upper end surface of the second cylinder;

f. excavate soil from the inside of the first cylinder and the second cylinder, and inject high-pressure water inward through the second water inlet of the second water pipe, so that from the first The high-pressure water jet from a water outlet flushes the soil at the lower end of the first cylinder into the first cylinder, thereby causing the first cylinder and the second cylinder to be subjected to their own gravity Sink to a predetermined depth.
The construction method of the underground space according to claim 9, characterized in that, in the above step c and/or step e, it further comprises installing a third water pipe, wherein the third water pipe is in the first cylinder The outer side wall communicates with the outside and communicates with the second water inlet.