JPH03169914A - Laying of underground structure and open shield machine therefor - Google Patents

Abstract

PURPOSE:To make laying of an underground structure possible in dry condition by connecting, in an open shield machine provided with a work chamber and an opening, a pipe body to a connecting end that is made to project in said work chamber, by injecting silt into a clearance formed by thrusting forward of the shield machine and by letting said silt consolidate. CONSTITUTION:In an open shield machine A, a work chamber 7 is formed with a floor board 27, a front and a rear partition board 5 and 25 assembled in a tail frame 22. An opening 8 is provided to rear partition wall 5, and a connection end of a pipe body 54b that is already laid is made to project into the inside of the work chamber 7, and a pipe body 54a brought into the work chamber 7 is connected to said connecting end in dry condition. Then the rear partition wall 5 is moved forward with the open shield machine A thrusted forward to a position where the connecting end of the pipe body 54b projects toward the inside of the work chamber 7. Slit 73 with consolidating agent mixed therein is injected into a clearance between the rear partition wall 5 and slit 73' that is already consolidated. Then a movable partition wall 26 is retracted, securing a new space whereat the pipe bodies can be connected, for continuation of a series of pipe laying works.

Description

[Detailed description of the invention] The invention in the field of industrial application uses an open shield machine and a mud or mud solidification method in combination to bury underground structures such as water and sewer pipes and box carparts. It concerns the construction method and the open shield machine used for it.

``Conventional technology'' Two known methods for burying underground structures include the open shield method using an open shield machine and the muddy water solidification method.

In the former method, while excavating with a towed or self-propelled open shield machine, the underground structure is laid in a dry state in a work room confined inside the open shield machine, and the underground structure is buried behind the open shield machine. This method involves backfilling underground structures. The advantage is that it can be buried in a dry state, resulting in high work efficiency and high precision.

In the latter method, the walls of the buried trench are stabilized with muddy water containing bentonite, etc., the buried trench is excavated with an excavator such as a bassokho, and the underground structure is laid in the muddy water, after which a solidifying agent is mixed. This is used to solidify muddy water.

The latter construction method is as follows: (1) long-distance simultaneous burial/circulating solidification agent mixing method (2)
) There are two main types of methods: burying the car pipe, and stirring and mixing the solidifying agent with air blow.

(1) and (2) The common advantages of both are that deformation of the surrounding ground and other construction pollution are extremely small, no special foundation work is required, and a pipeline with excellent water retention can be created. The advantage of (2) is that the daily construction work is carried out in a series of cycles, making it possible to open the road at night.

``Problems to be solved by the invention'' By the way, in the open shield construction method, the ground around the front excavation part of the open shield machine becomes loose due to the collapse of the face, and the ground around the rear part becomes loose due to insufficient compaction of backfill soil or delays in backfilling. This may cause loosening. Furthermore, the surrounding ground is affected by subsidence of the surrounding ground due to the drop in groundwater due to water changes in the excavated area, and damage to surrounding structures is likely to occur, such as cranking, subsidence, tilting, and drying of wells.

In addition, there is a risk that damage to the buried structure may occur due to the movement of the foundation material or the collapse of the tail void as the aircraft moves forward, such as joint dislodgement, subsidence, cracking, bending, etc. .

In addition, regarding the muddy water solidification method, problems common to (1) and (2) above are that the cost is high because it uses muddy water, and the positioning is time-consuming because the burial work is done in muddy water. The excavation and burying work is performed in muddy water, and then the assimilating agent is mixed, resulting in two-step work. Furthermore, in (1) the work area is long because long distances are buried at the same time, and in (2) special equipment is required to join each pipe one by one in muddy water.

Therefore, the purpose of the invention was to improve the open shield machine and make it possible to bury underground structures in a dry state by using both the mud solidification method and the open shield method. be.

Furthermore, the invention aims to reduce costs by using generated soil in conjunction with the mud solidification method, and also eliminates the impact on surrounding structures and buried underground structures in the open shield construction method. The purpose is to

``Means for Solving the Problems'' In the open shield machine according to the invention, a working chamber is formed in the tail frame in which a dry condition is ensured by a floor plate, a front partition wall, and a rear partition wall. The connecting portion of the installed pipe body is made to protrude from the opening provided in the rear partition wall, and the pipe body carried into the working chamber and the connecting portion are connected within the working chamber. After the connection, muddy soil (or muddy water) mixed with a solidifying agent is injected into the clearance created between the rear bulkhead and the solidified muddy soil (or muddy water) by the propulsion of the open shield machine to solidify it.

When the open shield machine is provided with a moving means and the rear bulkhead is a movable bulkhead that can be moved back and forth, the pipe bodies are connected by moving the movable bulkhead to secure a space where the connection can be made,
Perform in the work room as described above. After the connection, the movable bulkhead is moved forward, and mud (or muddy water) mixed with a solidifying agent is injected into the clearance between the movable bulkhead and the assimilated mud to solidify it.

``Operation'' The open shield machine has a working chamber formed within its tail frame by a floor plate and front and rear bulkheads.

The working chamber is kept dry by preventing the infiltration of unsolidified mud (or muddy water) mixed with a solidifying agent.

In addition, since the rear bulkhead has an opening, the connection part of the pipe that has already been installed can be made to protrude into the opening, and the connection part of the pipe carried into the work room can be connected in a dry state. Can be connected.

When the connection work is completed in the work chamber, the open shield machine is propelled to move the rear bulkhead forward until the connecting portion of the connected pipe body protrudes into the work chamber. Then, muddy soil (or muddy water) mixed with a solidifying agent is injected into the clearance between the rear partition wall and the solidified muddy soil (or muddy water).

Work will be carried out in sequence to bury the pipe.

In addition, when the rear bulkhead is a movable bulkhead, the movable bulkhead is moved by a moving means to secure a space in the work chamber where the tube can be connected, and the tube is connected as described above in the dry work chamber. Connecting.

Next, the movable bulkhead is advanced to a position where the connecting part of the newly installed pipe protrudes into the work chamber, and mud mixed with a solidifying agent is poured into the clearance between the movable bulkhead and the solidified mud (or muddy water). (or muddy water).

After injecting muddy soil (or muddy water) mixed with a solidifying agent into the clearance, the movable bulkhead is moved back relative to the front bulkhead by a moving means, and the open shield machine is moved forward with the movable bulkhead remaining in its original position. , again secure a space in the work room where the pipe can be connected.

A series of steps will be performed to bury the pipe body.

The connection between the pipe body and an underground structure that cannot pass through the opening, such as a manhole, is achieved by creating a connection space in a dry state between the moved bulkhead and solidified mud (or muddy water). and ensure that.

"effect" The effects of the invention are listed below.

+11 Since underground structures can be buried in a dry state, smooth connections can be made without the need for special equipment.

(2) Mud soil (or muddy water) mixed with solidifying agent for backfilling
is injected, solidifying the mud (muddy water) only takes one step.

It is economically advantageous to use a mud solidification method that uses generated soil instead of mud water. (3) The continuous cycle of excavation, installation of underground structures, solidification, and lining can be performed, allowing for quick release of traffic. (4) There is no need to change the water in the excavation part, and muddy water or mud is injected at the same time as the open shield machine moves forward, so there is no impact on the surrounding ground and damage to surrounding structures can be prevented.

(5) By solidifying muddy water or mud, a homogeneous and stable ground with sufficient strength can be formed around the outer periphery of underground structures. Therefore, there is no need for foundation materials, it is possible to prevent damage to buried underground structures, and it is possible to construct pipelines with excellent watertightness. (6) Also, since heavy machinery can be placed on the burial line, there is no need for a horizontal work zone. (7) The only part that is open is the part of the shield machine that is always open, so safety is high.

(8) If the rear bulkhead of an open shield machine is a movable bulkhead, pipes and manholes can be installed continuously.

(9) By injecting still water or muddy water into the front excavation part to prevent the face from collapsing, construction can be carried out on soft ground or in a water-retaining layer without the use of auxiliary methods such as ground improvement.

``Embodiments'' The invention will be described in detail below based on illustrated embodiments.

First, to explain the open shield machine that implements the invention, open shield machines are divided into towed open shield machines and self-propelled open shield machines. In addition, among the left and right tail frames and front and rear bulkheads that form the work chamber for burying underground structures, there is a bulkhead-fixed open shield machine in which the rear bulkhead is fixed, and a bulkhead-moving type in which the rear bulkhead moves back and forth. It is divided into type open shield machine and type open shield machine.

Therefore, there are four types: A, bulkhead fixed type towed open shield machine B, bulkhead fixed type self-propelled open shield machine C, bulkhead moving type towed open shield machine D, bulkhead moving type self-propelled open shield machine.

Bulkhead-fixed type towed open shield @A Figures 1 and 2
The figure shows a bulkhead-fixed towed open shield machine A. 1 is the front frame, 2 is the tail frame,
Both frames 1, 2 are integrally formed. A towing receiving frame 3 is provided on the front frame 1, and the open shield machine A is propelled by hooking a packet of a backhoe carrying out excavation work on the receiving frame 3 within the front frame 1.

4 is a front partition, 5 is a rear partition, and 6 is a floor plate, and a work chamber 7 is formed by the partition walls 4 and 5, the floor plate 6, and the left and right tail frames 2. The length of the working chamber 7 in the front-back direction is at least longer than the underground structure to be buried, for example, a pipe body such as a sewer pipe, and is a length that does not hinder the burying work. In addition, the work room 7 is divided into the front and rear partition walls 4, 5, the floorboard 6,
It is also possible to form it with left and right side plates (not shown).

8 is a circular opening penetrating the lower part of the rear partition wall 5. The inner diameter of the opening 8 is set to be large enough to follow the misalignment between the opening 8 and the tube body caused by the propulsion of the open shield machine, that is, the forward movement of the rear bulkhead 5.

Reference numeral 9 denotes a water stop frame, which has a cylindrical body having a smaller diameter than the opening 8 and a larger inner diameter than the outer diameter of the pipe that is the underground structure to be buried;
It is formed from a flange part.

10 is a wire seal (or air bag).

The water stop frame 9 prevents muddy soil or muddy water from entering the work chamber 7 from between the opening 8 and the pipe body. The water stop frame 9 is removably attached to the rear partition wall 5 by a magnet 1lb provided on the flange portion. These pair of magnets lla and 1lb are detachable. In addition, the water stop frame 9 is
The position can be adjusted by adjusting jacks 12 which are removably attached to the upper, lower, left and right sides of the inner surface of the rear partition wall 5 around the opening 8. Therefore, even if the tube is inserted into the working chamber 7 through the opening 8, the working chamber 7 can be kept in a dry state.

Bulkhead-fixed self-propelled open shield machine B Bulkhead-fixed self-propelled open shield machine B is a known self-propelled open shield machine with a tail frame equipped with a structure similar to the above-mentioned open shield machine 8. It is.

The bulkhead moving type towed open shield machine C and the bulkhead moving type towed open shield machine C have the same structure as that provided in the tail frame of the bulkhead moving type self-propelled open shield machine described later. Further, the front frame is also of a known structure, similar to the bulkhead-fixed type towed open shield machine A described above.

Bulkhead moving type self-propelled open shield machine D Figures 4 to 6 show a bulkhead moving type self-propelled open shield machine D.

21 is a front frame, a tail frame 22, a plurality of propulsion jacks 23, and left and right skin plates 24, which are similar to known self-propelled open shield machines.

25 is a front bulkhead fixed to the front end of the tail frame 22; 26 is a movable bulkhead in which the rear bulkhead is movable back and forth; 27
is the floorboard. A working chamber 28 is formed by the front partition wall 25, the movable partition wall 26, the floor plate 27, and the left and right tail frames 22.

The movable bulkhead 26 has an opening 2 similar to the rear bulkhead 5 described above.
9 is provided. Similarly, the wire seal 31 (
A water stop frame 30 that prevents muddy soil or muddy water from entering the work chamber 28, and a pair of magnets 3 that removably attach the water stop frame 30 to the movable bulkhead 26.
Adjustment jacks 33 for adjusting the positions of the water stop frames 30 are provided respectively. The magnets 32a and 32b are made removable.

Next, a means for moving the movable partition wall 26 will be explained.

Reference numeral 34 designates four feed screws for moving the movable partition wall 26 in the front-rear direction, and has approximately the same length as the length of the working chamber 28 in the front-rear direction. The feed screws 34 and 34 are screwed into female screws 35 attached to the top and bottom, left and right sides of the movable bulkhead 26 near the tail frame 22, respectively. 36
are large gears fixed to the tip of each feed screw 34, and mesh with small gears 37 fixed to the drive shaft of the motor M, respectively. The motor M is fixed to the tail frame 22. Rubber plate seals 38 are attached to both left and right ends and the lower end of the movable partition wall 26 to prevent muddy soil or muddy water from entering into the working chamber 28.

Therefore, when each motor M is rotated synchronously, the feed screw 34 is rotated via the small gear 37 and the large gear 36.
can be moved forward or backward.

Note that the means for moving the movable partition wall 26 is not limited to that in the embodiment, and may be arbitrary, such as using a jack or a wire.

Reference numeral 40 denotes an air bag, which is attached to the left and right outer surfaces of the rear portion of the tail frame 22, and is inflated when the front frame 21 is propelled. The Airbuffuku 40 is used as a method to secure the propulsion reaction force of the open shield machine D, and when inflated, it takes the shape of a mountain! This makes it possible to reduce ground disturbance. 4l is an air pipe arranged in the tail frame 22, and the air bag 40
It is connected via an air hose to an air combiner (not shown) (see Figures 5 and 6). Instead of the air bag 40, a known side reaction plate may be provided on the side of the tail frame 22.

Reference numeral 42 denotes a mud water pipe connected to a plant not shown, which is disposed on the tail frame 22 and is connected to the air buffet 4.
A muddy water injection nozzle 43 that penetrates through the airbag 40 and opens on the outer surface of the airbag 40 is connected (see FIGS. 5 and 6).
. Further, reference numeral 42' denotes a muddy water pipe to which a nozzle 43' opening at the rear end of the tail frame 22 is connected. A wire seal 44 is attached to the rear end of the tail 22.

Note that instead of the above embodiment, the positions of the water stop frames 30 provided on the rear partition wall 5 and the movable partition wall 26 may be adjusted using screws or wires instead of using the adjusting jacks 12 and 33.

In addition, when steel plates are used for the water stop frames 9 and 30, the water stop frames 9 and 30
, 30 side magnets llb and 32b may be omitted.

Next, a method for burying underground structures using the open shield machine described above will be described.

Burying method using bulkhead-fixed towed open shield machine A A burial trench 52 is excavated with a backhoe 51. As shown in FIG. 1, muddy water (or still water) 53 is filled in the front frame l of the open shield machine A in the burial trench 52, and excavation is performed in the muddy water 53. Therefore, there is no need for auxiliary construction methods such as ground improvement to prevent collapse of the face, and construction can be performed on soft ground or water retention layers. In addition, since there is no need to change the water, there is no risk of surrounding ground sinking or the well drying up.

The connecting portion of the tube body 54b that has already been buried is projected into the working chamber 7 through the opening 8 of the rear partition wall 5. Adjustment jack 12
The position of the opening 8 is adjusted to adjust the misalignment. A pedestal 55 installed on the floorboard 6 (can be moved vertically and horizontally)
Next, the pipe body 54a to be newly installed is carried in by a crane (not shown), and the position is adjusted and connected to the pipe body 54b. A balance weight 56a is housed in the tube 54a to prevent the tube from floating, and a connecting wire 57 connects the balance weight 56a with the balance weight 56b of the installed tube 54b. Further, in order to prevent the tube body from being pulled out when the open shield machine A is propelled, a retraction anchor 58 is attached to the buried tube 54a. The connection work of the pipe body 54a can be performed in the work chamber 7 which has ensured a dry condition.

Next, the packet 51 of the Ba Nokho 51 is moved until the tip of the tube 54a reaches a position in the work chamber 7 where the next tube can be connected, that is, to a position where the next tube can be carried in. ' by hooking it on the receiving frame 3, the open shield machine A is propelled.

With the promotion of Open Shield @A, as shown in Fig. 3, the clearance between the rear bulkhead 5 and the solidified mud 59' is filled with mud mixed with a solidifying agent from a plant not shown. Inject 59. Continue the following steps in sequence. The mud 59 is generated from excavation work to reduce costs.

In addition, the pipe body 54b and the pipe body that has been installed (not shown) following the pipe body 54b are backfilled with mud 59 mixed with a solidifying agent. Since the mud gradually solidifies, a road surface lining is applied on top of the solidified mud 59. Heavy equipment can be placed on the road surface. the balance weight 56a,
56b, the pipe suspension wire (not shown) is removed after the mud 59 has solidified.

The burial method using the bulkhead-fixed self-propelled open shield machine B is the same as the above-mentioned method using the bulkhead-fixed self-propelled open shield machine A, except that the open shield machine B is propelled by a propulsion jack. This method is similar to the construction method.

Burial method using bulkhead moving type towed open shield machine C This is the same as the method using bulkhead moving type self-propelled open shield machine D described below, except that open shield machine C is towed by a backhoe. .

The construction method using the bulkhead moving self-propelled open shield machine D is performed in the following order.

(1) Propulsion of the front frame 21 from the position shown in Fig. 6 after connecting the pipes and pouring the mud is done using the air pipe 4.
1, the propulsion jack 23
(see Figure 5).

(2) At the same time as removing the air from the air bag 40, muddy water 72 is injected from the nozzle 43 from a plant (not shown) through the muddy water piping 42 into the clearance created between the air bag 40 and the buried groove 71 (see FIG. 6). The muddy water 72 also has the effect of reducing friction when the tail frame 22 is propelled.

Next, the propulsion jack 23 is retracted to advance the tail frame 22. At the same time, as shown in FIG. 6, muddy water 72' mixed with a solidifying agent sent from a plant not shown in the figure is poured into the clearance created between the rear end of the tail frame 22 and the already solidified mud 73'. It is injected from a nozzle 43' via a pipe 42'. At this time, the muddy water 72 and the muddy water 72' mixed with the solidifying agent are separated by a wire seal 44 so that they do not mix.

In addition, by rotating the motor M in synchronization with the propulsion of the tail frame 22 and rotating the feed screw 34, the movable bulkhead 26 is moved backward relative to the tail frame 22.
Keep it in its original position.

(3) Repeat operations (1) and (2) until a space in which the pipe can be installed is secured in the work chamber 28.

(4) Once the space is secured, a new pipe 74a is carried into the work room 28 using a crane (not shown) and connected to the installed pipe 74b on the floorboard 27 (FIG. 4). After the connection, the feed screw 34 is rotated to advance the movable bulkhead 26 to the position shown in FIG. 6.

When the underground structure is manhole 75, etc. is installed in the space created by moving the movable bulkhead 26 forward (8th
figure).

(5) Mud 73 mixed with a solidifying agent is injected from a plant not shown in the figure into the clearance created between the movable bulkhead 26 and the solidified mud 73' as the movable bulkhead 26 moves forward (
(See Figure 7). In the embodiment, generated soil is used as the mud 73 to reduce costs.

The pipe body is buried by repeating the operations (1) to (5) in sequence.

In addition, even in the example using the open shield machine D, similar to the construction method using the open shield machine A, the construction method with balance weights and retractable anchors is also carried out. The same applies to filling the inside of the front frame 2l with muddy water (or still water). In each of the above embodiments, a case was shown in which backfilling was performed using generated mud, but it is also possible to use muddy water instead of generated mud.

[Brief explanation of the drawing]

Figures 1 to 3 show a bulkhead-fixed towed open shield machine and a construction method using it. FIG. 1 is a sectional view, FIG. 2 is a view taken along the line I-1, and FIG. 3 is a schematic sectional view of the open shield machine being propelled after connecting the tubes. Figures 4 through 8 show a self-propelled bulkhead moving open shield machine and a construction method using it. Figure 4 is a cross-sectional view of the state in which the tube bodies are connected, Figure 5 is a rear view with the air bag inflated to propel the front frame, and Figure 6 is the state in which the tube bodies are connected and the tail frame is propelled. Fig. 7 is a schematic cross-sectional view of the state in which mud is injected. FIG. 8 is a schematic cross-sectional view showing a state in which a pipe body and a manhole are connected. A... Bulkhead fixed type towed open shield machine 2... Tail frame 4... Front bulkhead 5... Rear bulkhead 6... Floor plate 7 ・ ・ 8 ・ ・ D ・ ・ 22 25 26 27 28 29 34...Working room...Opening...Self-propelled open shield machine with moving bulkhead...Tail frame...Front bulkhead...Moving bulkhead...Floor plate...Working room...Opening... feed screw

Claims (1)

[Claims] 1. In the tail frame of the open shield machine, a floor plate,
The front and rear bulkheads form a working chamber that ensures a dry condition, and the connecting parts of the installed pipes protrude into the working chamber through an opening in the rear bulkhead, and the pipes are carried into the working chamber. and the above-mentioned connection part in the work room, and muddy soil or muddy water mixed with a solidifying agent is injected into the clearance created between the rear bulkhead and the solidified muddy soil or muddy water by the propulsion of the open shield machine to solidify it. A method of burying underground structures characterized by: 2. The rear bulkhead of the working chamber is a movable bulkhead that moves back and forth, and the pipes are connected in the working chamber where a space for connection is secured by moving the movable bulkhead, and after connection, the movable bulkhead is moved forward. 2. The method for burying an underground structure according to claim 1, wherein mud or mud mixed with a solidifying agent is injected into the clearance created between the movable bulkhead and the solidified mud or mud to solidify it. 3. The underground structure burying method according to claim 1 or 2, wherein when the open shield machine is self-propelled, the front frame is propelled by a lateral reaction force by inflating an air bag provided on the side of the tail frame. . 4. The method for burying an underground structure according to claim 1 or 2, wherein the balance weights installed inside the pipe bodies are sequentially connected in the work chamber when the pipe bodies are connected, and are removed after the mud or muddy water has solidified. 5 A work chamber is formed by providing a front bulkhead at the front end of the tail frame of the open shield machine, a rear bulkhead at the rear end, and a floor plate at the bottom, and an opening into which the tube is inserted is provided in the rear bulkhead. An open shield machine characterized by the following. 6. The open shield machine according to claim 5, further comprising a moving means for moving the rear bulkhead in the front-back direction to make it a movable bulkhead. 7 The opening has a size that can follow the misalignment between the opening and the tube body caused by the propulsion of the open shield machine, and there is a gap between the opening and the tube body on the inner surface of the rear bulkhead. Claim 5: The water stop frame that seals the clearance created by the water stop frame is closely attached with a magnet so as to be movable in the vertical and horizontal directions.
Or the open shield machine described in 6.