JP7449261B2 - Excavation base and how to start and reach the excavation machine - Google Patents

Description

The present invention relates to an excavation base and a method for starting and arriving at an excavation machine.

In the propulsion method and the shield method, a part of the created vertical shaft is generally used as an excavation base for starting and reaching the excavator. The shape and dimensions of the shaft are generally planned to ensure the internal space necessary for either the launch or arrival of the excavator, and therefore one shaft is used as an excavation base. In this case, the launch and arrival of the excavator will generally be carried out at different times.
If multiple (for example, two) tunneling machines are to be launched and arrived at the same time in one shaft, the starting reaction equipment (or launch chamber) and the arrival receiving equipment (or arrival chamber) must be installed in the shaft. ) must be installed separately, and the scale (planar scale) of the shaft will naturally increase in order to secure the installation space. Therefore, in environments where land restrictions are severe, such as in urban areas, if the scale of the shaft cannot be increased, it will be impossible to launch and arrive at a single shaft with multiple excavators at the same time.
On the other hand, inside a shaft, there is generally a support (such as an upright or a strut that extends horizontally inside the shaft) to support earth pressure and earth water pressure, but some of the shafts are not excavated as described above. When used as a base, the excavation base tends to occupy a large proportion of the space within the shaft, and when attempting to install shoring to avoid the excavation base or excavation machine, the size of the shaft increases further, and the shaft As the scale of the shoring increases, the scale of the shoring (shoring specifications) must also increase.
For the above reasons, it is desired that an excavation base for an excavator using a part of a shaft be as small as possible while allowing the excavator to start and arrive at the same time.

Here, Patent Document 1 describes a system that improves the efficiency of assembly and disassembly work of a circumferential shield excavator in an excavation base, enables stable excavation work, and launch and reach protection devices such as a water stop device at the mine entrance and ground improvement. An excavation base for a circumferential shield excavator has been proposed, which can have a simple shape. Specifically, it is an excavation base where a circumferential shield excavator that constructs a circumferential tunnel in which the alignment is vertically directed is launched or at least arrives at, and the cutter of the circumferential shield excavator faces. A wall surface facing the cutter is provided, and the wall surface facing the cutter is provided on a normal line to the linear shape of the circumferential tunnel.

JP 2018-100519 Publication

According to the excavation base described in Patent Document 1, at least one of the launch and arrival of the circumferential shield excavator is performed, but the launch and arrival of the circumferential shield excavator are carried out at the same time, and furthermore, the excavation base There is no disclosure of any means for achieving simultaneous launch and arrival while minimizing the scale of the event.

An object of the present invention is to provide an excavation base that is as small as possible, and a method for starting and arriving at an excavator, while making it possible to start and arrive at the same time.

In order to achieve the above object, one aspect of the excavation base according to the present invention is as follows:
An excavation base installed inside a shaft, from which an excavator applied to the shield method or propulsion method starts and reaches,
Inside the excavation base, a starting chamber including a starting wall surface for the excavating machine to launch and a reaching chamber including a reaching wall surface for the excavating machine to reach are partitioned by a bulkhead,
The bulkhead has an end fixed to an inner wall surface of the excavation base, and the reaching chamber is attached to a plurality of linear beam frames projecting convexly with respect to the launching chamber, and the plurality of beam frames. Equipped with a steel plate,
A starting reaction force when the excavator starts is received by the inner wall surface via the bulkhead,
The reaching chamber is characterized in that it can be filled with a filler material for receiving the reaching excavator.

According to this aspect, the excavation base provided inside the shaft is divided into the starting chamber and the reaching chamber via the bulkhead inside the shaft, and the beam frame forming the bulkhead is such that the reaching chamber is opposed to the starting chamber. By having a convexly projecting linear shape, the starting reaction force of the excavator can be effectively received in the area of the bulkhead that enters the convex interior of the starting chamber, and the bulkhead in the reaching chamber can effectively receive the starting reaction force of the excavator. By bulging out toward the launch room, it is possible to secure enough space to accommodate the excavators, and while it is possible to launch and arrive at the same time for these excavators, the launch room and arrival The scale of the excavation base equipped with the chamber can be made as small as possible.
In other words, when viewed from the side of the excavation base, the bulkhead has a dogleg shape, a bridge-like shape, or a curved line shape and surrounds the arrival chamber. For example, the bulkhead extends vertically between the launch chamber and the arrival chamber. Since it is not divided into sections, it is possible to reduce the scale of the excavation base as much as possible. In the launch chamber, the bulkhead that protrudes toward the launch chamber receives the launch reaction force and transmits the received launch reaction force to the inner wall surface of the excavation base via the end of the beam frame. It is possible to form a beam frame (bulkhead) with a high load capacity and a reasonable cross section.
In addition, the reaching chamber can be filled with filler that accepts the tunneling machine, so that the reaction force of the tunneling machine that cuts the reaching wall surface and enters the reaching chamber is absorbed through the filling material and the bulkhead. It can be received on the inner wall of the excavation base.

The excavation base of this aspect can be installed in a shaft to which both the shield construction method and the propulsion construction method are applied, and it can be installed at the same time (at the same time or at a slightly different time) with respect to the launch chamber and the arrival chamber. Allows two tunneling machines to carry out launching and reaching, or one tunneling machine launches from the launching chamber and excavates circumferentially, e.g. in a horizontal or vertical plane, to reach the reaching chamber. making it possible to do so. In addition to forms in which vertical shafts are constructed vertically or diagonally downward from the ground, there are also forms in which shafts are constructed vertically or diagonally downward from, for example, underground tunnels (main line tunnels, ramp tunnels, etc.).
In the propulsion method, a main push device equipped with a main push jack is installed in the launch chamber so as to take a reaction force to the bulkhead, and the propulsion box, which is lowered to the excavation base via a shaft, is placed at the top in the excavation direction. It is connected to the rear of the excavator, and is propelled by the main push jack and the middle push jack of the middle push device interposed between the propulsion boxes.
In addition to excavators that are not equipped with a propulsion jack, excavators that excavate in a horizontal or vertical plane, for example in the circumferential direction, are excavators that are equipped with a propulsion jack that enables directional control and independent propulsion. There are various types of excavators depending on the type of excavation, such as excavators whose front and middle bodies are connected by a folding jack, and whose middle and rear bodies are connected by a propulsion jack (or direction control jack). Applicable.

Further, in another aspect of the excavation base according to the present invention,
One end of a shoring that passes through the bulkhead in the lateral direction is fixed to the inner wall surface of the launch chamber, and the other end of the shoring is fixed to the inner wall surface of the reaching chamber,
When the excavator reaches the reaching chamber, a region of the shoring that penetrates the reaching chamber is removed to form a replacement shoring, and an end of the renewed shoring is received by the bulkhead. It is characterized by being replaceable.

According to this aspect, the support such as a strut that extends the excavation base (vertical shaft) in the horizontal direction penetrates the bulkhead, that is, the bulkhead and the support intersect in a plane. This makes it possible to form an excavation base that is as small as possible, even though it is equipped with a starting room, a reaching room, and a support. Furthermore, when the excavator reaches the reaching chamber, the area of the shoring that penetrates the reaching chamber is removed to form a renewed shoring, and the end of the renewed shoring can be freely replaced with the bulkhead. This makes it possible to receive an excavator in the reaching room while maintaining the shoring function of the shoring.
Here, when we say that the shoring passes through the bulkhead "laterally", we mean that if the shaft is constructed in such a way that it extends vertically, the struts forming the shoring will extend horizontally. This means penetrating the bulkhead, and if the shaft is constructed diagonally, the struts will extend perpendicular to this diagonal direction or horizontally to penetrate the bulkhead. It means things, etc.

Further, in another aspect of the excavation base according to the present invention,
The renewed shoring is equipped with a jack,
With the end of the renewed shoring being replaced by the bulkhead, when the bulkhead receives the starting reaction force, the preload corresponding to the earth pressure supporting force offset by the starting reaction force is It is characterized in that it can be freely loaded onto the renewed shoring from a jack.

According to this aspect, the replacement shoring that is formed by removing a part of the shoring is equipped with a jack (such as a strut jack), and when a starting reaction force acts on the bulkhead, the replacement shoring is replaced via the bulkhead. Anticipating that the earth pressure bearing capacity of the shoring will be offset by the starting reaction force, a preload equivalent to the starting reaction force is applied in advance, so that even if the starting reaction force acts after the renewal shoring is formed, It becomes possible to stably support the applied earth pressure and earth water pressure while stably receiving the starting reaction force.

Further, in another aspect of the excavation base according to the present invention,
One side of the part of the bulkhead faces the starting chamber and receives the starting reaction force when the main pushing jack provided in the main pushing device starts the excavator and its subsequent propulsion box. It is a receiving side,
The other surface of the part of the bulkhead is a reaching reaction force receiving surface that faces the reaching chamber and faces a cutter face of the reaching machine and receives a reaching reaction force when the digging machine reaches the destination. It is characterized by

According to this aspect, the starting reaction force by the main push jack is received by the starting reaction force receiving surface on one side facing the starting chamber of the bulkhead, and the reaching reaction force receiving surface on the other side facing the reaching chamber of the bulkhead. By receiving the arrival reaction force, when the excavator starts and arrives at the same time, for example, reaction forces in opposite directions act on both sides of the bulkhead (start reaction force receiving surface and arrival reaction force receiving surface). As a result, excessive cross-sectional forces (bending, shearing, etc.) acting on the bulkhead are eliminated. The above effect can be further enhanced by setting the starting position and the reaching position on both sides of the bulkhead so that the starting direction and the reaching direction of the excavator are in the same straight line.

Further, in another aspect of the excavation base according to the present invention,
The arrival reaction force received by the arrival reaction force receiving surface is provided from the excavator propelled by the source pushing device that applies the starting reaction force to the starting reaction force receiving surface. .

According to this aspect, the excavator, which is propelled from the launch chamber by the main pushing jack that takes a reaction force to the bulkhead, and the plurality of propulsion boxes connected to the rear of the excavator are moved in the circumferential direction, for example, in a horizontal plane or in a vertical plane. The bulkhead is propelled by the main thruster, reaches the reaching chamber, and is pushed back by the reaching reaction force. The excavator is propelled back and pushes back the main push jack), and in this case, reaction forces in opposite directions act on both sides of the bulkhead (the starting reaction force receiving surface and the arriving reaction force receiving surface). and will cancel each other out.

Further, in another aspect of the excavation base according to the present invention,
The filler is characterized in that it is one of fluidized soil, poorly mixed mortar, and poorly mixed concrete.

According to this aspect, by applying one of fluidized soil, poorly mixed mortar, and poorly mixed concrete as the filler, the cutter face of the excavator that enters the filler is not damaged. Furthermore, it becomes possible to effectively transmit the arriving reaction force to the bulkhead at the lowest possible material cost.

Further, one aspect of the method for starting and reaching the excavator according to the present invention is as follows:
A method for starting and arriving at an excavator applied to the shield method or the propulsion method, in which the excavator starts and reaches from an excavation base provided inside a shaft,
Inside the excavation base, a starting chamber including a starting wall surface for the excavating machine to launch and a reaching chamber including a reaching wall surface for the excavating machine to reach are partitioned by a bulkhead,
The bulkhead has an end fixed to an inner wall surface of the excavation base, and the reaching chamber is attached to a plurality of linear beam frames projecting convexly with respect to the launching chamber, and the plurality of beam frames. Equipped with a steel plate,
The reaching chamber can be filled with a filling material that receives the reaching excavator,
a starting step of starting the excavator from the starting chamber via the starting wall surface while receiving a starting reaction force at the time of starting the excavating machine on the inner wall surface via the bulkhead;
The present invention is characterized by comprising a reaching step of causing the excavating machine to reach the reaching chamber via the reaching wall surface and receiving the excavating machine inside the filling material.

According to this aspect, by using the excavation base of the present invention and carrying out the starting process of starting the excavation machine from the excavation base and the reaching process of causing the excavation machine to reach the said excavation base, A small-scale excavation base makes it possible to carry out the start process and the arrival process at the same time (at the same time or at slightly different times), thereby shortening the construction period.

Further, in another aspect of the method for starting and arriving at an excavator according to the present invention,
One end of a shoring that passes through the bulkhead in the lateral direction is fixed to the inner wall surface of the launch chamber, and the other end of the shoring is fixed to the inner wall surface of the reaching chamber,
In the reaching step, before the excavator reaches the reaching chamber, a region of the shoring that penetrates the reaching chamber is removed to form a renewed shoring, and an end of the renewed shoring is removed. It is characterized in that it is replaced by the bulkhead.

According to this aspect, since the support such as a stub that extends the excavation base (vertical shaft) in the horizontal direction penetrates the bulkhead, the starting process and the arrival stage are carried out at the smallest possible excavation base. The steps can be carried out, for example, at the same time, and furthermore, when the excavator reaches the reaching chamber, the area of the shoring that penetrates the reaching chamber is removed to form the replacement shoring, and the end of the replaced shoring is removed. By replacing it with a bulkhead, it is possible to receive an excavator in the arrival room while stably supporting earth pressure and earth water pressure with the updated shoring.

Further, in another aspect of the method for starting and arriving at an excavator according to the present invention,
The renewed shoring is equipped with a jack,
In the reaching step, when the end of the renewed shoring is replaced by the bulkhead and the bulkhead receives the starting reaction force, the earth pressure supporting force is offset by the starting reaction force. It is characterized in that a corresponding preload is loaded from the jack onto the replacement shoring.

According to this aspect, the renewed shoring formed by removing a part of the shoring is equipped with a jack, and when a starting reaction force acts on the bulkhead, the earth pressure support of the replaced shoring is supported via the bulkhead. In anticipation that the force will be canceled out by the starting reaction force, a preload equivalent to the starting reaction force is applied in advance, so even if the starting reaction force acts after the renewal shoring is formed, the starting reaction force can be stabilized. This makes it possible to stably support the applied earth pressure and earth water pressure.

According to the excavation base and the method for starting and arriving at the excavation machine of the present invention, the scale can be made as small as possible while making it possible to start and arrive at the excavation machine at the same time at the excavation base. It is possible to shorten the construction period.

FIG. 2 is a longitudinal sectional view illustrating an excavation base according to an embodiment and a circumferential tunnel constructed by a method for starting and arriving at an excavator according to an embodiment. It is a process diagram explaining the construction method of an example of an excavation base. FIG. 3 is a view taken along arrow III-III in FIG. 2, and is a plan view of the lower part of the shaft. FIG. 3 is a view taken along the line IV-IV in FIG. 2, and is a vertical cross-sectional view of the shaft. FIG. 3 is a process diagram following FIG. 2 to explain the construction method of the excavation base. Following FIG. 5, it is a process diagram explaining the construction method of the excavation base. FIG. 7 is a view along arrow VII-VII in FIG. 6, and is a vertical cross-sectional view of the shaft. FIG. 7 is a process diagram following FIG. 6 to explain the construction method of the excavation base. FIG. 9 is a view along arrows IX-IX in FIG. 8, and is a vertical cross-sectional view of the shaft. FIG. 8 is a view taken along the line XX in FIG. 8, and is a plan view of the lower part of the shaft. It is a process diagram explaining an example of the starting and arrival method of an excavator. FIG. 12 is a view taken along the line XII-XII in FIG. 11, and is a vertical cross-sectional view of the shaft. Continuing from FIG. 11, it is a process diagram illustrating an example of a method for starting and arriving at an excavator. FIG. 14 is a process diagram following FIG. 13 to explain an example of a method for starting and arriving at an excavator. FIG. 14 is a process diagram illustrating an example of a method for starting and arriving at an excavator, following FIG. 14 . It is a side view which expands and shows the state in which the end part of the renewal shoring is replaced by the bulkhead. FIG. 17 is a view taken along arrows XVII-XVII in FIG. 16; FIG. 16 is a view taken along arrows XVIII-XVIII in FIG. 16; FIG. 15 is a process diagram illustrating an example of a method for starting and arriving at an excavator, following FIG. 15 .

Hereinafter, an excavation base and a method for starting and arriving at an excavator according to an embodiment will be described with reference to the accompanying drawings. Note that, in this specification and the drawings, substantially the same constituent elements may be given the same reference numerals to omit redundant explanation.

[Excavation base according to embodiment]
First, with reference to FIGS. 1 to 10, an example of the excavation base according to the embodiment will be described along with its construction method. Here, FIG. 1 is a longitudinal sectional view illustrating an excavation base according to an embodiment and a circumferential tunnel constructed by a starting and reaching method of an excavator according to an embodiment. Moreover, FIG. 2, FIG. 5, FIG. 6, and FIG. 8 are process charts explaining the construction method of the excavation base in order.

As shown in Figure 1, when connecting and widening the main line tunnel HT (e.g. main line shield tunnel) that has already been constructed underground in underground G with the lamp tunnel RT (e.g. lamp shield tunnel) located on the side thereof, , a vertical shaft T will be constructed using the ramp tunnel RT and extending vertically below it. Note that this vertical shaft may extend diagonally downward instead of vertically.

The shaft T is constructed to a predetermined depth while supporting earth pressure and earth water pressure with struts K arranged at predetermined intervals in the vertical direction. The excavation base 100 to be carried out is constructed. A bulkhead 40 is provided inside the excavation base 100, and the bulkhead 40 allows the excavation base 100 to have a starting chamber 50 in which the excavation machine M starts, and a circumferential tunnel CT constructed in the underground G and returned to the ground. It is divided into a reaching chamber 60 where the incoming excavator M reaches. FIG. 1 shows a state in which the excavator M has reached the reaching chamber 60. Incidentally, the excavator M that constructs the circumferential tunnel CT in the illustrated example can also be referred to as a circumferential shield machine.

As shown in FIG. 1, the bulkhead 40 has an inverted dog-shaped linear shape when viewed from the side, and due to the bulkhead 40 having such a side view shape, the reaching chamber 60 is convex with respect to the launching chamber 50. It is overhanging. A plurality of main push jacks BJ constituting the main push device BD are attached to one side of the bulkhead 40.

A plurality of propulsion boxes S are sequentially suspended from the ramp tunnel RT to the excavation base 100 via a shaft T, and the plurality of propulsion boxes S are connected behind the excavation machine M located forward in the excavation direction. By propelling the propulsion box group SG formed by S through the underground G, a circumferential tunnel CT in a vertical plane is constructed.

The circumferential tunnel CT in the illustrated example is a single circle that surrounds the main tunnel HT and the ramp tunnel RT, but it may be a tunnel with various vertical shapes such as an ellipse or a track shape, and has at least a curved linear section. All you have to do is stay there. Starting from the constructed circumferential tunnel CT, a plurality of tunneling machines (not shown) construct a plurality of shield tunnels in a chain over the widening section. For example, after multiple leading shield tunnels are constructed at intervals, a trailing shield tunnel is constructed between them while cutting a part of the adjacent leading shield tunnel, and the adjacent leading shield tunnel and trailing shield tunnel are By constructing a large-section annular body made of reinforced concrete inside the tunnel, the large-section tunnel is excavated while applying this large-section annular body (large-section tunnel) to earth retaining, and the main tunnel HT and ramp tunnel RT are constructed. The widening section is constructed by communicating with each other.

As shown in FIGS. 2 to 4, in the illustrated example, prior to constructing the vertical shaft T, a plurality of frozen pipes FB are extended vertically (diagonally) downward from the ramp tunnel RT, frozen soil F is created, and the deep foundation construction method is used. Construct the vertical shaft T by etc. In FIG. 2, the circumferential tunnel CT to be finally constructed as shown in FIG. 1 is indicated by a dotted line.

Below the shaft T, the excavation base 100 includes a start/reach area 101 and a work stage SS, and various excavation equipment is temporarily placed on the work stage SS.

The shaft T is formed by, for example, stacking cylindrical steel shells one above the other and joining them to each other, and as shown in FIG. 2, it has an upper part T1 and a lower part T2 where the excavation base 100 is constructed. are doing. In the upper part T1 of the shaft T, struts K that support earth pressure and earth water pressure are arranged at predetermined intervals in the vertical direction, and as shown in Figure 4, there are also spacings in the horizontal direction at each vertical level. A plurality of struts K are arranged at intervals of . There is a gate type crane D inside the ramp tunnel RT, and the excavator M and the propulsion box S that are suspended by the gate type crane D are delivered to the excavation base 100 below through the gap between the struts K. It has become.

At the lower part T2 of the shaft T, opening reinforcing beams 22 are provided above and below a starting wall surface 24 (the right wall surface in FIG. 2) where the excavator M starts, and a reaching wall surface 28 (in FIG. 2) that receives the arriving excavator M. Opening reinforcing beams 26 are also provided above and below the left wall surface. The upper and lower opening reinforcement beams 22 and 26 are connected by a pair of left and right opening reinforcement columns 23 (see FIG. 7) to form a rectangular frame-shaped reinforcement body, and the starting wall surface 24 and the reaching wall surface 28 are connected to a rectangular frame-shaped reinforcement body. reinforced by. The opening reinforcing beam 22 and the opening reinforcing column 23 are enclosed inside a steel shell that forms the shaft T, for example. As shown in FIG. 2, the starting wall surface 24 and the reaching wall surface 28 are provided at positions where the vertical alignment of the circumferential tunnel CT intersects with the shaft, and in the illustrated example, the starting wall surface 24 is located at a relatively lower level. ing.

In the lower part T2 of the shaft T, above the start and reach area 101 and the work stage SS, which are located side by side, there is provided a shoring 10 (strut) that extends horizontally to support earth pressure and earth water pressure. . The shoring 10 in the illustrated example is formed by two struts, upper and lower.

When the shaft T is constructed and the work stage SS is installed in the lower part T2, next, as shown in FIG. 32 is placed and fixed. The entrance member 32 is equipped with a wire brush and has an inner hollow shape corresponding to the curvature of the circumferential tunnel CT to be constructed, so that the excavator M is started along the curvature through the entrance member 32. There is.

As shown in FIG. 6, a starting pedestal 34 is mounted and fixed on the support pedestal 30 at the rear of the entrance member 32 (on the reaching wall surface 28 side), and the excavator M is carried out by the portal crane D of the ramp tunnel RT. After being suspended downward in the X1 direction through the shaft T and placed on the starting pedestal 34, the excavator M is moved rearward on the starting pedestal 34 in the X2 direction.

When starting the excavator M, the starting wall surface 24 is cut into mirrors. Here, as shown in FIG. 7, since the periphery of the starting wall surface 24 is reinforced with a rectangular frame-shaped reinforcement body consisting of the opening reinforcing beam 22 and the opening reinforcing column 23, when the starting wall surface 24 is mirror-cut. However, the rigidity of the wall of the excavation base 100 is guaranteed. Incidentally, when the excavator M reaches the excavation base 100, the reaching wall surface 28 is mirror-cut, and the excavator M is accepted into the excavation base 100.

After mirror-cutting the starting wall surface 24, as shown in FIG. A water stop structure is formed by making contact with each other, and a space is formed behind the excavation base 100 (on the reaching wall surface 28 side).

The bulkhead 40, which has been schematically explained with reference to FIG. 1, is installed in the created space. The bulkhead 40 has two ends 43 fixed to the inner wall surface of the excavation base 100, and has a beam frame 42 formed of a plurality of H-shaped steels or the like having an inverted dogleg shape in side view. , and a steel plate 44 that is welded or otherwise joined to the reaching chamber side surface (left side in FIG. 8) of a plurality of beam frames 42.

The starting and reaching area 101 of the excavation base 100 is divided into a starting chamber 50 and a reaching chamber 60 by the bulkhead 40 which has an inverted dogleg shape when viewed from the side. More specifically, due to the inverted dogleg-shaped bulkhead 40, both chambers are formed such that the reaching chamber 60 projects convexly from the starting chamber 50.

As shown in FIGS. 9 and 10, the beam frames 42 forming the bulkhead 40 are arranged on the left and right sides of the shoring 10 so as to sandwich it therebetween. That is, at the stage where the bulkhead 40 is formed, the shoring 10 supports the earth pressure and earth water pressure acting on the wall surface of the lower part T2 of the shaft T while maintaining its original shape. The intersection of the shoring 10 and the bulkhead 40 is connected to each other by a connecting piece 46 such as a flint piece. In this manner, the bulkhead 40 having an inverted dogleg shape in side view has two ends 43 of the beam frame 42, which is a component thereof, and has an inverted dogleg shape in side view, on the inner wall surface of the excavation base 100. The convex portion of the bulkhead 40 is fixed to the shoring 10 via the connecting piece 46.

In this way, the bulkhead 40 functions as a partition wall that divides the starting and reaching area 101 of the excavation base 100 into the starting chamber 50 and the reaching chamber 60. Further, as is clear from FIG. 8, in the bulkhead 40 which has an inverted dogleg shape in side view, the reaching chamber 60 protrudes convexly from the starting chamber 50, and both chambers For example, compared to a configuration in which both chambers are partitioned by a vertical bulkhead, the scale of the excavation base 100 can be made as small as possible, and the launch chamber 50 and the arrival chamber 60 can be divided into two. A chamber can be formed.

In addition, a partial region 41 constituting the bulkhead 40, which has an inverted dogleg shape in side view, has a thick and flat plate shape, and as shown in FIG. (the radial direction of the circumferential tunnel CT). One surface 41a of the partial region 41 of the bulkhead 40 faces the launch chamber 50, the other surface 41b of the partial region 41 faces the arrival chamber 60, and the one surface 41a and the other surface 41b are located on opposite sides. are doing. As will be described later, the main push device BD is configured to take a reaction force on one side 41a of the partial area 41 to start and propel the excavator M and the propulsion box S. On the other hand, the excavator M that has reached the arrival chamber 60 is received by the other surface 41b of the partial area 41 by taking a reaction force through the filling material filled in the arrival chamber 60.

In addition, as will be described later, when receiving the excavator M into the reaching chamber 60, the reaching chamber penetrating region of the shoring 10 that penetrates the reaching chamber 60 is removed, and the end of the shoring 10 is built up on the bulkhead 40. It can be replaced. At this time, the bulkhead 40 has the function of supporting the lower part T2 of the shaft T together with the remaining shoring.

In this way, the bulkhead 40 functions as a partition wall that divides the excavation base 100 into the launch chamber 50 and the arrival chamber 60, and supports the excavation base 100 (lower part T2 of the shaft T) during the construction process of the circumferential tunnel CT. It has the function of an engineer.

[Starting and reaching method of excavator according to embodiment]
Next, an example of a method for starting and arriving at an excavator according to an embodiment will be described with reference to FIGS. 11 to 19. Here, FIG. 11, FIG. 13 to FIG. 15, and FIG. 19 are process charts sequentially illustrating a method for starting and arriving at an excavator.

As shown in FIGS. 11 and 12, a main push jack BJ constituting a main push device BD is installed on one side 41a of a partial region 41 of the bulkhead 40. As shown in FIGS. As shown in FIG. 12, the illustrated example of the main pusher BD includes a plurality of main pusher jacks BJ in the upper and lower stages, spaced apart from each other.

When starting the excavator M, as shown in Fig. 13, the freezing pipe FB on the starting port side is pulled upward in the The frozen soil F is also thawed to suppress the digging resistance of the excavator M. The excavator M excavates in the Y1 direction along the longitudinal alignment of the circumferential tunnel CT, and the propulsion boxes S sequentially provided from the ramp tunnel RT via the shaft T are sequentially connected to the rear of the excavator M. A propulsion box group SG formed by a plurality of propulsion boxes S is propelled underground G.

When propelling the excavator M and the propulsion box group SG, a starting reaction force P2, which is a reaction force of the thrust P1, acts on the bulkhead 40 from the main push jack BJ, and the acting starting reaction force P2 acts on the bulkhead 40. It is transmitted (received) in the Y2 direction to the inner wall surface of the excavation base 100 (the above is the starting process).

Although not shown, if the thrust is insufficient, an intermediate push device including an intermediate push jack may be interposed in the propulsion box group SG. In addition, in the illustrated curved propulsion method, a copy cutter (not shown) is extended from the side of the cutter face of the excavator M to create an over-excavation section, and propulsion is performed while filling the over-excavation section with lubricant. be done. At this time, especially when constructing a circumferential tunnel CT in a vertical plane as shown in the illustrated example, the sliding material in the over-excavation section prevents the excavation from progressing due to the weight of the propulsion box group SG at the rear and the weight of the excavator M. The machine M may meander through the sliding material, making precise directional control difficult.

Therefore, it is preferable that the plurality of propelling boxes S forming the propelling box group SG incorporate a gripper device (not shown) in which a gripper protrudes laterally. For example, the propulsion box group SG is fixed to the ground by protruding grippers from the propulsion box S located at the forefront of the propulsion box group SG (located at the rear of the excavator M) and any one propulsion box S behind it. By doing so, the excavator M can easily control its direction without being affected by the weight of the propulsion box group SG.

The excavator M excavates in the vertical plane in the circumferential direction, and the propulsion box group SG is propelled at any time to construct the circumferential tunnel CT, and the excavator M accesses the reaching chamber 60 of the excavation base 100. When the tunneling machine M reaches the reaching chamber 60, as shown in FIG. Fill it with.

Next, as shown in FIG. 15, of the shoring 10, the reaching chamber penetrating region that penetrates the reaching chamber 60 is completely removed to form a renewed shoring 15, and a separate filler material is placed above the reaching chamber 60. By filling 70B, the entire area of the reaching chamber 60 is filled with the filler 70.

The filler 70 (70A, 70B) transmits the reaching reaction force of the excavator M reaching the reaching chamber 60 to the bulkhead 40, and is as inexpensive as possible and prevents the cutter face of the excavator M from digging. It is preferable to use a material with as low resistance as possible. From these viewpoints, it is preferable to use fluidized soil, poorly mixed mortar, poorly mixed concrete, or the like as the filler 70.

16 to 18 show a state in which the end portion 17 of the renewed shoring 15, which was formed by removing the reaching chamber penetration region 12 of the shoring 10, has been replaced by the bulkhead 40.

The renewed shoring 15 is equipped with a jack 19 therein, and more specifically, the shoring 10 that has existed from the beginning before the renewed shoring 15 is formed is already equipped with the jack 19.

When the end portion 17 of the renewed shoring 15 is replaced by the bulkhead 40, when the bulkhead 40 receives the starting reaction force P2, a preload corresponding to the earth pressure supporting force offset by the starting reaction force P2 is applied. A jack 19 loads the replacement shoring 15.

As shown in FIGS. 17 and 18, axial force due to earth pressure and earth water pressure is applied to the two beam frames 42 installed so as to sandwich the reaching chamber penetration area 12 of the shoring 10. , is transmitted in the Y3 direction from both bifurcated ends 17 of the renewed shoring 15, and in the beam frame 42, as shown in FIG. The axial force is further transmitted in the Y4 direction, and is transmitted to the inner wall surface of the excavation base 100.

After the reaching chamber 60 is filled with the filler 70, as shown in FIG. The excavator M is made to reach the filling material 70 in the Y6 direction.

The arrival reaction force P3 upon arrival of the excavator M is transmitted to the other surface 41b of the partial region 41 of the bulkhead 40, so this other surface 41b serves as an arrival reaction force receiving surface. On the other hand, since the starting reaction force P2, which is the reaction force of the thrust force P1 from the main push jack BJ, acts on one surface 41a of the partial region 41 of the bulkhead 40, this one surface 41a serves as a starting reaction force receiving surface. Become. At this time, the starting reaction force P2 and the arrival reaction force P3 caused by the main push jack BJ act on the plate-shaped partial region 41 in opposite directions (in opposite directions in the tangential direction of the longitudinal alignment of the circumferential tunnel CT). I will do it. Since these opposite starting reaction forces P2 and arrival reaction forces P3 cancel each other out, no excessive cross-sectional force is generated in the bulkhead 40 when the excavator M arrives.

Here, when receiving the excavation machine M into the arrival chamber 60, a propulsion box slip-out prevention material 80 is installed between the propulsion box S existing in the launch chamber 50 and the inner wall surface of the excavation base 100 (as described above). , arrival process).

The excavator M is equipped with an attached freezing tube (not shown) inside, and the attached freezing tube of the excavating machine M that has reached the reaching chamber 60 creates frozen soil in the opening area of the reaching chamber 60, and causes a stop at the opening. Ensure water-based. After ensuring watertightness at the opening, the reaching chamber 60 is removed and the excavator M is partially dismantled.

According to the illustrated method for starting and reaching the excavation machine, the excavation machine M is launched from the excavation base 100 using the excavation base 100 constructed at the lower part T2 of the shaft T, and the excavation machine M is brought into the excavation base 100. By carrying out the reaching process of reaching M, it becomes possible to carry out the starting process and the reaching process at the same time using the excavation base 100 as small as possible, and it is possible to shorten the construction period.

In addition, since the support 10 such as a strut that extends the excavation base 100 in the lateral direction (horizontal direction) passes through the bulkhead, when the excavation machine M reaches the reaching chamber 60, the support 10 The reaching chamber penetrating region 12 that penetrates the reaching chamber is removed to form the renewed shoring 15, and the end portion 17 of the renewed shoring 15 is replaced with the bulkhead 40, thereby improving the supporting function of the renewed shoring 15. It is possible to receive the excavator M in the reaching chamber 60 while maintaining the following.

At this time, the renewed shoring 15 is equipped with a jack 19, and when the starting reaction force P2 acts on the bulkhead 40, the earth pressure supporting force of the renewed shoring 15 is offset by the starting reaction force P2 via the bulkhead 40. In anticipation of this, a preload corresponding to the starting reaction force P2 is loaded in advance, so that even if the starting reaction force P2 acts after the updated shoring 15 is formed, the starting reaction force P2 is stably received. However, it becomes possible to stably support the applied earth pressure and earth water pressure.

It should be noted that other embodiments may be adopted in which other components are combined with the configurations listed in the above embodiments, and the present invention is not limited to the configurations shown here. In this regard, changes can be made without departing from the spirit of the present invention, and can be appropriately determined depending on the application form.

10: Shoring (horizontal shoring)
12: Reaching chamber penetration area 15: Renewal shoring 17: End 19: Jack 22, 26: Opening reinforcing beam 23: Opening reinforcing column 24: Starting wall 28: Reaching wall 30: Support frame 32: Entrance member 34: Starting frame 40: Bulkhead 41: Partial area 41a: One side (starting reaction force receiving surface)
41b: Other surface (reaching reaction force receiving surface)
42: Beam frame 43: End 44: Steel plate 46: Connection piece 50: Launching chamber 60: Reaching chamber 70, 70A, 70B: Filler 80: Propulsion box escape prevention material 100: Excavation base 101: Launching and reaching area HT: Main line Tunnel RT: Ramp tunnel D: Portal crane T: Vertical shaft K: Strut beam (shoring)
F: Frozen soil FB: Frozen pipe SS: Work stage S: Propulsion box SG: Propulsion box group M: Excavation machine BD: Main push device BJ: Main push jack CT: Circumferential tunnel G: Underground (ground)
P1: Thrust P2: Starting reaction force P3: Arrival reaction force

Claims (9)

An excavation base installed inside a shaft, from which an excavator applied to the shield method or propulsion method starts and reaches,
Inside the excavation base, a starting chamber including a starting wall surface for the excavating machine to launch and a reaching chamber including a reaching wall surface for the excavating machine to reach are partitioned by a bulkhead,
The bulkhead has an end fixed to an inner wall surface of the excavation base, and the reaching chamber is attached to a plurality of linear beam frames projecting convexly with respect to the launching chamber, and the plurality of beam frames. Equipped with a steel plate,
A starting reaction force when the excavator starts is received by the inner wall surface via the bulkhead,
The excavation base is characterized in that the reaching chamber can be filled with a filler material for receiving the arriving excavator. One end of a shoring that passes through the bulkhead in the lateral direction is fixed to the inner wall surface of the launch chamber, and the other end of the shoring is fixed to the inner wall surface of the reaching chamber,
When the excavator reaches the reaching chamber, a region of the shoring that penetrates the reaching chamber is removed to form a replacement shoring, and an end of the renewed shoring is received by the bulkhead. The excavation base according to claim 1, characterized in that it is replaceable. The renewed shoring is equipped with a jack,
With the end of the renewed shoring being replaced by the bulkhead, when the bulkhead receives the starting reaction force, the preload corresponding to the earth pressure supporting force offset by the starting reaction force is The excavation base according to claim 2, wherein the excavation base can be loaded onto the renewed shoring from a jack. One side of the part of the bulkhead faces the starting chamber and receives the starting reaction force when the main pushing jack provided in the main pushing device starts the excavator and its subsequent propulsion box. It is a receiving side,
The other surface of the part of the bulkhead is a reaching reaction force receiving surface that faces the reaching chamber and faces a cutter face of the reaching machine and receives a reaching reaction force when the digging machine reaches the destination. The excavation base according to any one of claims 1 to 3, characterized by: The arrival reaction force received by the arrival reaction force receiving surface is provided from the excavator propelled by the source pushing device that applies the starting reaction force to the starting reaction force receiving surface. , the excavation base according to claim 4. The excavation base according to any one of claims 1 to 5, wherein the filler is one of fluidized soil, poorly mixed mortar, and poorly mixed concrete. A method for starting and arriving at an excavator applied to the shield method or the propulsion method, in which the excavator starts and reaches from an excavation base provided inside a shaft,
Inside the excavation base, a starting chamber including a starting wall surface for the excavating machine to launch and a reaching chamber including a reaching wall surface for the excavating machine to reach are partitioned by a bulkhead,
The bulkhead has an end fixed to an inner wall surface of the excavation base, and the reaching chamber is attached to a plurality of linear beam frames projecting convexly with respect to the launching chamber, and the plurality of beam frames. Equipped with a steel plate,
The reaching chamber can be filled with a filling material that receives the reaching excavator,
a starting step of starting the excavator from the starting chamber via the starting wall surface while receiving a starting reaction force at the time of starting the excavating machine on the inner wall surface via the bulkhead;
A method for starting and reaching an excavator, comprising the steps of: causing the excavator to reach the reaching chamber via the reaching wall surface and receiving the excavator inside the filling material. One end of a shoring that passes through the bulkhead in the lateral direction is fixed to the inner wall surface of the launch chamber, and the other end of the shoring is fixed to the inner wall surface of the reaching chamber,
In the reaching step, before the excavator reaches the reaching chamber, a region of the shoring that penetrates the reaching chamber is removed to form a renewed shoring, and an end of the renewed shoring is removed. The method for starting and arriving at an excavator according to claim 7, characterized in that the bulkhead is replaced with the bulkhead. The renewed shoring is equipped with a jack,
In the reaching step, when the end of the renewed shoring is replaced by the bulkhead and the bulkhead receives the starting reaction force, the earth pressure supporting force is offset by the starting reaction force. 9. The method for starting and reaching an excavator according to claim 8, characterized in that a corresponding preload is loaded from the jack onto the replacement shoring.

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