JP4925461B2 - Earth retaining structure using steel pipe, construction method thereof and shield machine start-up construction method - Google Patents

Description

  The present invention is used for construction of a shaft, for example, and uses a retaining structure constructed by driving a plurality of steel pipes into the ground while connecting steel pipes, a construction method thereof, and the retaining structure. This is related to the shield machine construction method.

  In urban areas where various buildings and structures are forested, excavating the ground, setting up tracks such as subways, and constructing large-scale waterways for collecting and flowing sewage and rainwater in one place Has been done frequently. In this case, a lot of excavating machines called shield machines are used, and the shield machine is carried in and out using a shaft called a vertical shaft constructed by digging vertically in the ground, and the underground is excavated horizontally for excavation. The start and the arrival to be done.

  The shaft has a start shaft for carrying in and starting a shield machine, and a reaching shaft for reaching and carrying out the shield machine, and the shield machine started from the start shaft is for reaching the above The underground can be excavated horizontally toward the shaft and penetrated through an underground tunnel of a predetermined length. In conventional shafts, a structure for earth retaining is formed by connecting a plurality of steel pipes that are not formed with openings for passing through a shield machine into the ground, and a shaft is constructed. It was. Next, a shield machine is installed and installed in the steel pipe forming the shaft, and the ground is improved by injecting chemicals into the back ground through which the shield machine passes, and water and sediment are prevented from flowing into the steel pipe. After performing water treatment and installation of protective work, etc., mirror cutting was performed to open a part of the periphery of the steel pipe using a gas burner or the like.

  However, the improvement of the ground as described above leads to an increase in construction cost and an increase in the construction period, which is difficult. Further, the mirror cutting work is dangerous because it is a work in a state where the face of the shield machine is opened, and has been regarded as a problem in terms of safety. Therefore, in recent years, as shown in Patent Documents 1 and 2 below, an opening is formed in advance in a part of the peripheral body portion of the steel pipe constituting the retaining wall, and a slidable gate steel plate covering the opening is provided. A structure for earth retaining of a configuration arranged on the steel pipe has been proposed. And, according to such a structure for retaining earth, the mirror cutting operation for the steel pipe is unnecessary and the safety is improved, and the ground improvement work by the chemical solution is unnecessary by maintaining the pressure balance inside and outside the steel pipe. Therefore, the construction cost and the construction period can be shortened. Incidentally, Patent Document 1 discloses a configuration including a steel plate for a gate that can be slid in a vertical direction, and Patent Document 2 discloses a configuration including a steel plate for a gate that can be slid in a horizontal direction.

In addition, there are two types of steel plates for gates, one inside the steel pipe and one outside the steel pipe. In the former case, a large earth pressure is applied directly to the gate steel plate. For this reason, a strong and complex support structure for the steel plate for a gate that can withstand the soil water pressure is required, and it becomes difficult to ensure water stoppage. On the other hand, in the latter case, the steel plate for gate and the joint for connecting the steel plate for gate to the steel pipe project outside the steel pipe, so that the projecting portion becomes resistance when press-fitting the steel pipe, and the steel pipe Makes it difficult to settle. In particular, in the press-fitting using a rotary press-fitting machine that press-fits while rotating the entire circumference of the steel pipe, the above-mentioned projecting part generates a large rotational press-fitting resistance. This was performed by press-fitting using a rocking press machine that press-fits while swinging within a range of angles. However, there is a limit to the press-in depth of the steel pipe that can be press-fitted with a swing press-fitting machine, and there has been a demand for the development of a retaining structure that enables press-fitting using the rotary press-fitting machine that can be pressed deeper. Moreover, if press-fitting using a rotary press-fitting machine becomes possible, it will be possible to deal with construction such as reclaimed ground.
Japanese Patent Laid-Open No. 10-102979 JP 2006-132239 A

  The present invention has been made in view of the existence of such problems, and by eliminating protrusions that prevent the steel pipe from settling on the outer peripheral surface, it is possible to reduce not only the press fit resistance but also the swing press fit. A retaining structure using a steel pipe that does not require mirror cutting or ground improvement, can be used for rotational press-fitting, and can ensure high water-stopping with a relatively simple structure, a method for constructing the retaining structure, and It is an object of the present invention to provide a start reaching method for a shield machine using the earth retaining structure constructed by the construction method.

  In order to solve the above problems, a retaining structure using the steel pipe according to the first aspect of the present invention is a structure for retaining earth formed by placing a steel pipe in the ground, and a circumferential trunk portion. A steel pipe in which an opening for passing a shield machine is formed in a part of the steel pipe, a slidable gate steel plate addressed so as to close the opening, and an inflow of water or earth and sand from the outside into the steel pipe The water stop space is used as a storage space for storing the gate steel plate when the gate steel plate is expanded.

  According to this aspect, it can be set as the structure which does not provide a protrusion part in the outer peripheral surface of the structure for earth retaining, Therefore Press-fit resistance at the time of press-fitting a steel pipe in a ground becomes small. Therefore, the steel pipe can be press-fitted not only by rocking press-fitting but also by rotary press-fitting, and it is possible to cope with a deep press-fitting depth and press-fitting into the ground. In addition, by providing a water stop space, it is possible to effectively prevent the inflow of water and earth and sand from the outside into the steel pipe, and this water stop space can also be used as a storage space for the steel plate for the gate. Thus, effective use of the space and simplification of the structure of the structure for earth retaining are achieved.

  According to a second aspect of the present invention, there is provided a retaining structure using the steel pipe according to the first aspect, wherein the gate retaining steel plate is connected to the steel pipe in the retaining structure. The steel plate for the gate is provided on the same circumference as the steel pipe so as to coincide with the outer peripheral surface of the steel pipe, and the steel pipe is in close contact with the inner peripheral surface of the steel pipe. The joint and the inner steel plate are arranged to form a double steel pipe portion having no protruding portion on the outer peripheral surface.

  According to this aspect, the steel plate for the gate is arranged on the same circumference as the steel pipe, and the joint that becomes the protruding portion is arranged inside the steel pipe, so that the outer peripheral surface of the structure for earth retaining does not have irregularities. It becomes a smooth shape, and the press-fitting of the steel pipe into the ground becomes smoother. Further, since the inner steel plate is arranged in close contact with the inner peripheral surface of the steel pipe in the outer space of the joint protruding inside the steel pipe, the inner peripheral surface of the structure for earth retaining also has a smooth portion without a protruding portion. Thus, the workability is improved by preventing catching on the joint, and at the same time, the double steel pipe portion constituted by the steel pipe and the inner steel plate also improves the strength of the earth retaining structure against soil water pressure.

  According to a third aspect of the present invention, there is provided a retaining structure using the steel pipe according to the first aspect, wherein the gate steel plate is connected to the steel pipe in the retaining structure. The gate steel plate and the joint are provided in a projecting state outside the outer peripheral surface of the steel pipe, and the other outer peripheral surface of the steel pipe in which the gate steel plate and the joint are not provided. The outer steel plate is arranged in close contact with the outer peripheral surface of the gate steel plate and the joint on the outer side, and a double steel pipe portion having no protrusion on the outer peripheral surface is formed. To do.

  According to this aspect, the steel plate for a gate and the joint are provided in a protruding state outward from the outer peripheral surface of the steel pipe, but the outer steel plate is disposed in close contact with the other outer peripheral surface of the steel pipe. Therefore, the outer peripheral surface of the structure for earth retaining has a smooth shape without irregularities, and the press-fitting of the steel pipe into the ground becomes even smoother. Moreover, the strength with respect to the earth-water pressure of the earth retaining structure is improved by the double steel pipe portion constituted by the steel pipe and the outer steel plate.

  According to a fourth aspect of the present invention, in the earth retaining structure using the steel pipe according to the second aspect or the third aspect, the water stop space includes the steel pipe, the gate steel plate, the inner steel plate or the steel plate. It is formed in a space defined by an outer steel plate and a thin iron plate addressed to the remaining opening surface, and in the initial state where the gate steel plate is in a closed state, the water stop space is filled with a filler. The filling material is discharged to the outside from a discharge port formed in the thin steel plate when the gate steel plate is shifted to the expanded state.

  According to this aspect, the water stop space can be formed with an extremely simple structure by simply providing a thin iron plate using an existing space formed between a steel pipe, a steel plate for a gate, and an inner steel plate or an outer steel plate. By filling the water stop space with a filler, water stoppage at the time of placing the steel pipe is ensured. On the other hand, since the filler in the water stop space is discharged to the outside when the gate steel plate is expanded by the discharge port formed in the thin iron plate, the water stop space functions as a storage space for the gate steel plate. Further, since the surfaces of the steel pipe, the inner steel plate or the outer steel plate, and the thin steel plate on the water stop space side are the guide surfaces, the sliding operation of the gate steel plate is smooth. Further, by providing a thin iron plate and filling the water stop space with a filler, it is possible to prevent foreign substances from entering when the gate steel plate enters the water stop space.

  According to a fifth aspect of the present invention, in the earth retaining structure using the steel pipe according to the first aspect, the steel plate for the gate is provided in a vertical direction provided in close contact with the inner peripheral surface of the steel pipe. A slidable pull-up type steel plate for a gate, and a movable-side wedge guide having a tapered surface formed so as to be narrowed in a direction to close the opening is provided at both left and right edges of the gate steel plate. The water stop box in which the water stop space is formed to cover the moving range of the steel plate for the gate is provided inside the steel pipe, and the water stop facing the left and right edges of the steel plate for the gate. A fixed-side wedge guide having a tapered surface formed so as to be narrowed in the direction in which the opening is expanded is provided on both sides of the box. The steel plate for the gate is in sliding contact with the water stop box. The movable wedge It is characterized in that the de and being guided by the fixed-side wedge guide is configured to close the opening.

  According to this aspect, since the steel plate for gates is provided inside the steel pipe, there is no protrusion that prevents the steel pipe from settling on the outer peripheral surface of the structure for earth retaining. Therefore, as in the above embodiments, the press-fitting resistance when the steel pipe is press-fitted into the ground is reduced, and it is possible to cope with not only swinging press-fitting but also rotary press-fitting. Further, since the wedge action is exhibited by providing the fixed-side wedge guide and the movable-side wedge guide, it is possible to construct a strong gate steel plate support structure with a relatively simple configuration, and to ensure high water stoppage. In addition, since the gate steel plate is guided so that the inclined direction of the tapered surfaces of the fixed wedge guide and the movable wedge guide moves in the direction of closing the opening, it acts on the outer surface of the gate steel plate. The earth and water pressure to act acts as a force in the direction of closing the steel plate for gate.

  Moreover, since the inner wall surface of the said water stop box which forms the water stop space becomes a guide surface, the sliding operation | movement of the steel plate for gates becomes smooth. In addition, the provision of a sealed water stop box prevents foreign substances from entering when the gate steel plate enters the water stop space. In addition, a gate opening / closing drive device such as a hydraulic jack can be pre-assembled in the water stop box, and in this way, it is possible to simultaneously install the water stop box and the gate open / close drive device. . In addition, it is also possible to make the water stop box have a split structure, and in this way, it is possible to remove and reuse the part that can be reused after the completion of the construction.

  According to a sixth aspect of the present invention, in the earth retaining structure using the steel pipe according to the first aspect, the steel plate for the gate is provided in the left-right direction in close contact with the inner peripheral surface of the steel pipe. It is a slidable sliding steel plate for gates, and a movable-side wedge guide having a tapered surface formed so as to be narrowed in the direction of closing the opening is provided on the back surface of the gate steel plate, A water stop box in which the water stop space is formed inside the steel pipe so as to cover the moving range of the steel plate for the gate is provided, and the inner surface of the water stop box facing the back surface of the steel plate for the gate Is provided with a fixed-side wedge guide having a tapered surface formed so as to be narrowed in a direction in which the opening is expanded, and the gate steel plate and the movable-side wedge guide that are in sliding contact with each other in the water stop box. Fixed wedge And it is characterized in that it is configured so as to close the opening portion have been guided by the id.

  According to this aspect, since the steel plate for gates is provided inside the steel pipe as in the fifth aspect, there is a protrusion that prevents the steel pipe from settling on the outer peripheral surface of the structure for earth retaining. do not do. Therefore, as in the above embodiments, the press-fitting resistance when the steel pipe is press-fitted into the ground is reduced, and it is possible to cope with not only swinging press-fitting but also rotary press-fitting. Further, since the wedge action is exhibited by providing the fixed-side wedge guide and the movable-side wedge guide, it is possible to construct a strong gate steel plate support structure with a relatively simple configuration, and to ensure high water stoppage. In addition, the configuration is such that the gate steel plate moves in the direction of closing the opening by guiding the inclined direction of the tapered surfaces of the fixed-side wedge guide and the movable-side wedge guide to act on the outer surface of the gate steel plate. The earth and water pressure acts as a force in the direction of closing the steel plate for gate.

  Moreover, since the inner wall surface of the said water stop box which forms the water stop space becomes a guide surface, the sliding operation | movement of the steel plate for gates becomes smooth. In addition, the provision of a sealed water stop box prevents foreign substances from entering when the gate steel plate enters the water stop space. In addition, a gate opening / closing drive device such as a hydraulic jack can be pre-assembled in the water stop box, and in this way, it is possible to simultaneously install the water stop box and the gate open / close drive device. . In addition, it is also possible to make the water stop box have a split structure, and in this way, it is possible to remove and reuse the part that can be reused after the completion of the construction.

  The construction method of the earth retaining structure according to the seventh aspect of the present invention is an earth retaining structure in which a structure for earth retaining is formed by driving a steel pipe into the ground while connecting a plurality of steel pipes. A construction method using the steel pipe according to the fourth aspect in which an opening for passing a shield machine is formed in a part of a peripheral body portion, the opening being closed with a steel plate for a gate, and the water stop space A primary steel pipe placing step in which the steel pipe is placed in the ground using a press-fitting machine with a filler filled therein, and another steel pipe having no opening in the peripheral body portion, And a continuous steel pipe placing step of continuously placing other steel pipes into the ground using a press-fitting machine.

  According to this aspect, the press-fit resistance at the time of press-fitting a steel pipe is reduced by using the earth retaining structure using the steel pipe according to the fourth aspect that has no irregularities on the outer surface of the structure for earth retaining. It becomes possible to cope with not only rocking press-fitting but also rotary press-fitting, and it becomes possible to construct a deeper shaft. In addition, since the water-stopping space is filled with a filler, high water-stopping performance when a steel pipe is placed is also maintained. Moreover, since the mixing of the earth and sand and the foreign material into the water stop space is prevented by providing the thin iron plate, the foreign material is prevented from being mixed when the gate steel plate enters the water stop space.

  The construction method of the earth retaining structure according to the eighth aspect of the present invention is an earth retaining structure that forms a structure for earth retaining by driving a steel structure into the ground while connecting a plurality of steel pipes. A construction method using the steel pipe according to the fifth aspect or the sixth aspect in which an opening for passing a shield machine is formed in a part of a peripheral body, and the opening is closed with a steel plate for a gate. A primary steel pipe placing process in which the steel pipe is placed in the ground using a press-fitting machine in a state where the fixed wedge guide and the movable wedge guide are in contact with and in close contact with each other, and there is an opening in the peripheral trunk portion. The other steel pipe is not used, and the other steel pipe is continuously placed in the ground by using a press-fitting machine, and the steel pipe in which the opening portion is formed. A water stop box installation step for installing the water stop box inside And it is characterized in and.

  According to this aspect, by using the earth retaining structure using the steel pipe according to the fifth aspect or the sixth aspect, in which no protruding portion appears on the outer peripheral surface of the structure for earth retaining, the steel pipe can be inserted at the time of press fitting. The press-fitting resistance is reduced, so that not only swinging press-fitting but also rotary press-fitting can be handled, and a deeper shaft can be constructed. In addition, it is possible to construct a shaft that is durable and can withstand high soil water pressure by the wedge action of the fixed-side wedge guide and the movable-side wedge guide. In addition, by providing a sealed water stop box, it is possible to prevent foreign substances from entering when the gate steel plate enters the water stop space.

  The construction method of the retaining structure according to the ninth aspect of the present invention is the construction method of the retaining structure according to the seventh aspect or the eighth aspect, in which the press-fitting machine rotates the steel pipe all around. It is a rotary press-fitting machine that can be placed in the ground while the primary steel pipe placing step and the continuous steel pipe placing step are driven in the ground while rotating the steel pipe all around. It is a feature.

  According to this aspect, since the steel pipe can be press-fitted smoothly, the construction cost of the earth retaining structure can be reduced, and the construction period can be shortened. In addition, deeper shafts can be constructed.

  According to a tenth aspect of the present invention, there is provided a shield machine start reaching method using a steel pipe using the steel pipe according to the fourth aspect according to the construction method of the earth retaining structure according to the seventh aspect or the ninth aspect. After the structure is constructed, the earth retaining structure is used as a launching shaft or a reaching shaft, and the shield machine launching method for launching and reaching the shield machine with the opening being expanded, An entrance installation step of installing an entrance with wellhead concrete and packing in the double steel pipe around the opening, and balance the chamber pressure in the entrance with the earth and water pressure outside the double steel pipe to balance the pressure. The gate steel plate is advanced into the water stop space by adjusting the pressure balance and sliding the gate steel plate in the expanding direction. The gate steel plate expanding step for expanding the opening while discharging the filler in the water stop space from the discharge port formed in the thin steel plate to the outside, and the expanded opening A shield machine start and reach step for starting or reaching the shield machine directly.

  According to this aspect, since the mirror cutting work and the ground improvement work that have been conventionally performed are not required, the construction cost and the work period can be reduced, and the safety of the work is also improved. Also, in the gate steel plate expansion step that is performed prior to the shield machine start and arrival step, the filler in the water stop space is discharged to the outside simultaneously with the expansion operation of the gate steel plate. It can be used as a storage space for steel plates. Further, since the surfaces of the steel pipe, the inner steel plate or the outer steel plate, and the thin steel plate on the water stop space side are the guide surfaces, the gate steel plate can smoothly enter the water stop space.

  The shield machine start reaching method according to the eleventh aspect of the present invention is the steel pipe according to the fifth aspect or the sixth aspect according to the construction method of the earth retaining structure according to the eighth aspect or the ninth aspect. After the earth retaining structure using the structure is constructed, the earth retaining structure is used as a starting shaft or a reaching shaft, and the shield machine is started and reached with the opening being in an expanded state. An entrance installation step for installing an entrance made of wellhead concrete and packing in the steel pipe around the opening, and balancing the chamber pressure in the entrance with the earth and water pressure outside the steel pipe to obtain a pressure balance A pressure balance adjusting step, and sliding the gate steel plate in the expanding direction, the fixed-side wedge guide and the movable-side wedge guide; A gate steel plate expanding step for releasing the contact state and opening the opening portion, and a shield machine starting and reaching step for starting or reaching the shield machine directly from the expanded opening portion. It is characterized by being.

  According to this aspect, since the mirror cutting work and the ground improvement work that have been conventionally performed are not required, the construction cost and the work period can be reduced, and the safety of the work is also improved. In addition to the water stoppage at the entrance, high water stoppage is ensured by the wedge action of the fixed-side wedge guide and the movable-side wedge guide before the gate steel plate expansion process is performed. A desired water-stopping property is maintained by the entrance and the pressure balance during or after the process. Moreover, since the inner wall surface of the said water stop box which forms the water stop space becomes a guide surface, the approach to the water stop space of the steel plate for gates is performed smoothly.

  According to the present invention, since no protrusion is provided on the outer surface of the earth retaining structure to prevent the steel pipe from settling, the press-fit resistance when the steel pipe is driven into the ground is reduced. Therefore, it becomes possible to cope with not only the rocking press-fitting but also the rotary press-fitting, so that the steel pipe can be pressed deeper, and the steel pipe can be press-fitted into the reclaimed ground or the like. Further, since the water stop space is used as a storage space for the steel plate for the gate, the space can be effectively used, and the structure for retaining the earth can be made compact and simple. In addition, the adoption of a water-stopping space and the adoption of a fixed-side wedge guide and a movable-side wedge guide enable a relatively simple structure to ensure a high water-stopping property and prevent foreign matter from entering the water-stopping space. The Moreover, since the conventional mirror cutting work and ground improvement work are no longer required, the construction cost can be reduced and the construction period can be shortened.

  Hereinafter, the earth retaining structure using the steel pipe according to the present invention, the construction method of the earth retaining structure, and the best arrival method of the shield machine using the earth retaining structure constructed by the construction method The embodiment will be described with reference to the following Examples 1 to 4.

[Example 1]
(1) Structure of earth retaining structure (see FIGS. 1 to 6)
FIG. 1 is a side sectional view showing a construction state in which the earth retaining structure is press-fitted using a rotary press-fitting machine, and FIG. 2 is a side sectional view showing the earth retaining structure according to the first embodiment when the gate is closed. is there. 3 is the same as above, a front view, and FIG. 4 is the same as that shown in FIG. 5 is a side sectional view when the gate is expanded, and FIG. 6 is a front view of the same.

  The earth retaining structure 1 of the present embodiment is constructed prior to construction of a tunnel constructed underground, and is used as a side wall of a starting shaft or a reaching shaft of the shield machine 2. The earth retaining structure 1 is formed by driving a plurality of steel pipes 3 into the ground G while connecting them vertically. Specifically, as shown in FIG. 1, a dedicated press-fitting machine is used to swing and press these steel pipes 3 while swinging them within a certain angle range, and these steel pipes 3 are rotated all around. The starting shaft or the reaching shaft having a circular cross section is constructed by laying in the ground G using the rotary press-fitting method while pressing, excavating the earth and sand inside the steel pipe 3 and taking it out to the ground (hereinafter referred to as this shaft). Such a construction method is called “vertical shaft construction method”). In addition, in FIG. 1, the mode of construction in which the steel pipe 3 is driven by the rotary press-fitting method using the rotary press-fitting machine 4 is illustrated.

  The earth retaining structure 1 of the present embodiment is addressed so as to close the steel pipe 3 in which an opening (also referred to as a gate) 6 for passing the shield machine 2 is formed in a part of the peripheral body 5 and the opening 6. It is basically configured by including a slidable gate steel plate 7 and a water stop space 8 for preventing water and earth and sand from flowing into the steel pipe 3 from the outside. Further, the outer peripheral surface of the earth retaining structure 1 is not provided with a protruding portion that prevents the steel pipe 3 from settling, and the use of the water stop space 8 as a storage space for the steel plate 7 for the gate is implemented. It is set as the characteristic structure of the earth retaining structure 1 of an example. In addition, the retaining structure 1 of the present embodiment is provided with a hydraulic jack 9 or the like as an example of a gate opening / closing drive device for sliding the gate steel plate 7.

  A retaining structure 1A according to Example 1 includes a joint 10 for connecting the steel plate for gate 7 to the steel pipe 3 in addition to the above configuration, and an inner steel plate 11 disposed on the inner peripheral surface of the steel pipe 3. Is provided. The steel pipe 3 is a cylindrical member having an upper surface and a lower surface with a diameter of about 1500 to 5000 mm, and an opening 6 is formed in a part of the peripheral body portion 5 of the steel pipe 3 as described above. The shape of the opening 6 is, for example, a vertically long rectangular shape, and is formed to have a width that allows the shield machine 2 to pass through. Moreover, the lower end of the lowermost steel pipe 3 is provided with a blade edge 12 for facilitating press-fitting into the ground G due to the rotation of the entire circumference of the steel pipe 3. The blade edge 12 protrudes from the outer peripheral surface of the steel pipe 3 by a friction cut amount D in the radial direction.

  The gate steel plate 7 is a rectangular curved plate-like member curved with substantially the same curvature as the steel pipe 3. As a material for the gate steel plate 7, a high-strength material such as JIS standard SM490 or S35C can be applied as an example. In the present embodiment, the gate steel plate 7 is provided on the same circumference as the steel pipe 3 so as to coincide with the outer peripheral surface of the steel pipe 3. And the steel plate 7 for gates comprised in this way is temporarily fixed in the state which covered the said opening part 6 by using the fixing bolt 13 etc. which are shown in FIG.

  Further, the joint 10 described above is arranged in a close contact state on the inner peripheral surface of the steel pipe 3 around the opening 6. The joint 10 is a connecting member for attaching the gate steel plate 7 to the steel pipe 3 so as to be slidable in the vertical direction. Further, the inner steel plate 11 is disposed in close contact with the inner peripheral surface of the steel pipe 3 outside the joint 10. The inner steel plate 11 is formed by a rectangular curved plate having a curved curvature along the inner peripheral surface of the steel pipe 3, and the inner steel plate 11 and the steel pipe 3 have a double steel pipe portion 14 that does not have irregularities on the outer peripheral surface. Is formed. The inner steel plate 11 is formed with a circular opening 16 through which the shield machine 2 can pass.

  In this embodiment, the water stop space 8 uses a space defined by the steel pipe 3, the gate steel plate 7, and the inner steel plate 11, and a thin iron plate 15 is formed on the outer surface of the space. Attached. The thin iron plate 15 is configured by a rectangular curved plate curved with a curvature along the outer peripheral surface of the steel pipe 3, and two discharge ports 17 are formed on the thin iron plate 15 as an example. . Incidentally, the water stop space 8 is filled with a filler M as will be described later when the steel pipe 3 is placed, and the filler M is discharged from the discharge port 17 to the outside when the gate is expanded. ing.

  Moreover, when such a steel pipe 3 is settled to a predetermined depth, the inner peripheral surface of the double steel pipe portion 14 (in this embodiment, the inner peripheral surface of the inner steel plate 11), and the back surface of the gate steel plate 7 In the meantime, the hydraulic jack 9 mentioned above is attached, and the fixing bolt 13 for temporary fixing mentioned above is removed. And the earth retaining structure 1A which concerns on a present Example is constructed | assembled by driving all the steel pipes 3 to connect in the ground G. FIG. Moreover, since the earth retaining structure 1A constructed in this way is a compact shape having no irregularities on the outer peripheral surface, the press-fitting resistance is small, and the structure is suitable for the shaft construction method using the rotary press-fitting machine 4. ing.

(2) Construction method of earth retaining structure (see Fig. 7)
FIG. 7 is a side sectional view showing the construction procedure of the construction method of the earth retaining structure of the present invention in two stages (a) and (b). The construction method of the earth retaining structure of the present invention includes (a) a primary steel pipe placing step and (b) a continuous steel pipe placing step. Hereinafter, these steps will be specifically described.

(A) Primary steel pipe placing process (see FIG. 7 (a))
In the primary steel pipe placing step, the steel pipe 3 (hereinafter, the steel pipe 3 in which the opening 6 is formed, the opening 3 and the steel pipe 3 in which the opening 6 is formed) In the case of distinguishing and using the subsequent steel pipe 3 that does not have 6, the former steel pipe is identified as 3A and the latter steel pipe is identified as 3B. This is the process of setting up. The water stop space 8 is filled with a filler M in advance, so that water and earth and sand do not flow into the water stop space 8 from the discharge port 17 or the like when the steel pipe 3 is placed.

(B) Continuous steel pipe placing process (see FIG. 7 (b))
The continuous steel pipe placing step uses another steel pipe 3B that does not have the opening 6 in the peripheral body part 5, and uses the other steel pipe 3B using a press-fitting machine such as the rotary press-fitting machine 4 or the like in the ground G. This is a process of continuously placing in the process.

  That is, as shown in FIG. 7 (a), after the steel pipe 3A having the opening 6 formed therein is driven, the subsequent steel pipe 3B having no opening 6 is connected to the steel pipe 3A and rotated. The two steel pipes 3A and 3B connected using a press-fitting machine such as the press-fitting machine 4 are press-fitted together. Moreover, after the 2nd steel pipe 3B is driven, the 3rd steel pipe 3B is connected on the said 2nd steel pipe 3B, and the three steel pipes 3A, 3B, 3B are similarly press-fitted together. Thereafter, similarly, a predetermined number of steel pipes 3 are driven, whereby the earth retaining structure 1 having a predetermined depth as shown in FIG. 7B is constructed in the ground G.

  Then, the earth and sand in the steel pipe 3 cast at the same time as the steel pipe 3 is excavated and taken out to the ground, and when all the earth and sand in the steel pipe 3 is taken out, the fixing bolt 13 temporarily fixed is attached. If the hydraulic jack 9 is attached between the inner peripheral surface of the double steel pipe portion 14 and the back surface of the gate steel plate 7 by removing it, the construction of the earth retaining structure 1 according to the present embodiment is completed. It can be used as a starting shaft or a reaching shaft. In the case of the illustrated embodiment, the lowermost steel pipe 3 is a steel pipe 3A in which an opening 6 is formed. However, when the shield machine 2 is started and reached from an intermediate height of the vertical shaft, or from one vertical shaft When two upper and lower underground tunnels are constructed, the steel pipe 3 at the middle position is a steel pipe 3A with an opening 6 formed therein, or a plurality of steel pipes 3A with the opening 6 formed therein are provided with respect to one shaft. Of course, it is also possible to use.

(3) Start-up method for shield machine (see Fig. 8)
FIG. 8 is a side sectional view showing the start procedure of the start reaching method of the shield machine of this embodiment in four stages (a) to (d). The shield machine start-up method of the present embodiment includes (a) an entrance installation process, (b) a pressure balance adjustment process, (c) a steel plate expansion process for a gate, and (d) a shield machine start-up reach process. It is comprised by providing. Hereinafter, these steps will be specifically described.

(A) Entrance installation process (see FIG. 8 (a))
The entrance installation step is a step of installing the wellhead concrete 18 and the packing 19 in the double steel pipe portion 14 around the opening 6 to complete the entrance 20. That is, a mold frame (not shown) is installed around the start arrival part of the shield machine 2, the concrete well 18 is placed, cured and solidified, and then the mold frame is removed. And the entrance 20 is completed by installing the packing 19 in the edge part of the wellhead concrete 18 shape | molded by the predetermined shape. Next, when the shaft is a start shaft, the shield machine 2 is lowered from the ground into the start shaft, and the shield machine 2 is positioned at a predetermined start position in the vertical direction of the start shaft.

(B) Pressure balance adjustment step (see FIG. 8B)
The pressure balance adjustment step is a step of balancing the chamber pressure in the entrance 20 with the soil water pressure outside the double steel pipe portion 14 to achieve a pressure balance. That is, when the shield machine 2 is started, as shown in FIG. 8B, a predetermined position in the excavation direction in which the cutter face 22 on which the face 21 of the shield machine 2 is formed faces the entrance 20. Set shield machine 2 to. Next, a filling material M is filled from the outside into the chamber 23 of the entrance 20 defined by the wellhead concrete 18, the packing 19, and the cutter face 22, and the chamber pressure in the chamber 23 is increased to increase the pressure on the back surface of the face 21. Balance with external soil water pressure to ensure the pressure balance.

(C) Gate steel plate expansion process (see FIG. 8 (c))
The steel plate expansion process for gates is a process in which the steel plate for gates 7 is caused to enter the water stop space 8 by sliding the steel plate for gates 7 in the expansion direction O, thereby opening the opening 6. is there. That is, while the pressure balance between the chamber pressure in the chamber 23 and the external soil water pressure is ensured, the hydraulic jack 9 is operated and the gate steel plate 7 is slid in the expanding direction O (upward in this embodiment). Let The gate steel plate 7 is guided by the joint 10 and enters the water stop space 8, and the filler M in the water stop space 8 is discharged to the outside from the discharge port 17 formed in the thin steel plate 15. Move while. And when the steel plate 7 for gates is completely accommodated in the water stop space 8, the opening part 6 will be in an expanded state and the shield machine 2 will be able to start.

(D) Shield machine start arrival process (see FIG. 8 (d))
The shield machine start and reach step is a step for starting or reaching the shield machine 2 directly from the expanded opening 6. That is, when the shield machine 2 is started, the shield machine 2 is put into an operating state, the cutter face 22 is rotated while the shield machine 2 is propelled at a predetermined speed, and the shield machine 2 is opened in the start shaft. Start from 6 to ground G. Even when the shield machine 2 reaches the start, the pressure balance between the chamber pressure in the chamber 23 and the external soil water pressure is maintained as it is. Therefore, the shield machine 2 can be started and reached directly without improving the ground or installing a protective work as in the prior art.

[Example 2]
(1) Structure of earth retaining structure (see FIGS. 9 to 13)
FIG. 9 is a side sectional view of the earth retaining structure according to the second embodiment when the gate is closed, and FIG. 10 is a front view of the same. 11 is a cross-sectional view taken along the line BB in FIG. 10, and FIG. 12 is a side cross-sectional view when the gate is expanded. FIG. 13 is a front view of the above.

  The retaining structure 1B according to the second embodiment is similar to the retaining structure 1A according to the first embodiment. The steel pipe 3 in which the opening 6 is formed, the steel plate 7 for the gate that covers the opening 6, and the steel pipe 3 A water stop space 8 that prevents inflow of water and earth and sand into the inside and a joint 10 for connecting the steel plate for gate 7 to the steel pipe 3 are provided, and the steel pipe 3 is replaced with the inner steel plate 11. The outer side steel plate 24 arrange | positioned at the outer peripheral surface is provided. The structure of the steel pipe 3 is substantially the same as that of the steel pipe 3 of the first embodiment, except that the shape of the opening 6 is a circular shape that allows the shield machine 2 to pass therethrough.

  Further, the structure of the gate steel plate 7 and the joint 10 is substantially the same as the structure of the gate steel plate 7 and the joint 10 of Example 1, but in Example 2, the gate steel plate 7 and the joint 10 are the outer periphery of the steel pipe 3. The point which is provided in the protruding state outside the surface is different. In Example 2, in addition to the steel pipe 3 in which the gate steel plate 7 and the joint 10 are not provided, the outer peripheral surface is in close contact with the outer peripheral surface of the gate steel plate 7 and the joint 10. The outer steel plate 24 described above is arranged in a state.

  The outer steel plate 24 is formed by a rectangular curved plate having a curvature along the outer peripheral surface of the steel pipe 3, and the outer steel plate 24 and the steel pipe 3 form a double steel pipe portion 14 having no irregularities on the outer peripheral surface. Yes. The thickness of the outer steel plate 24 is about 25 mm, and is set to be smaller than the friction cut amount D of the blade edge 12 provided at the lower part of the steel pipe 3. Moreover, the outer side steel plate 24 is a hollow member, and is filled with a filler M inside. As an example, a vertically long rectangular opening at a position corresponding to the surface of the steel pipe 3 where the opening 6 is formed. 25 is formed. The width dimension of the opening 25 is set to a width dimension through which the shield machine 2 can pass.

  Also in this embodiment, the gate steel plate 7 is temporarily fixed with the opening 6 covered by using a fixing bolt 13 or the like shown in FIG. 24 when the steel pipe 3 is press-fitted. In the present embodiment, the water stop space 8 uses a space defined by the steel pipe 3, the gate steel plate 7, and the outer steel plate 24. A similar thin iron plate 15 is attached.

  Moreover, when such a steel pipe 3 is settled to a predetermined depth, the inner peripheral surface of the double steel pipe portion 14 (in this embodiment, the inner peripheral surface of the steel pipe 3) and the back surface of the gate steel plate 7 The hydraulic jack 9 is attached between them, and the fixing bolt 13 for temporary fixing described above is removed. And all the steel pipes 3 to be connected are driven into the ground G, whereby the earth retaining structure 1B according to the present embodiment is constructed. Moreover, since the earth retaining structure 1B constructed in this way is a compact shape having no irregularities on the outer peripheral surface, similarly to the first embodiment, the shaft construction method using the rotary presser 4 with low press-fitting resistance. The structure is suitable for.

  In addition, about (2) the construction method of the retaining structure and (3) the start reaching method of the shield machine for the retaining structure 1B according to the present embodiment, the retaining structure according to the first embodiment Since it is the same as (2) the construction method of the earth retaining structure for 1A and (3) the start-up construction method of the shield machine, detailed description is omitted here.

[Example 3]
(1) Structure of earth retaining structure (see FIGS. 14 to 19)
FIG. 14 is a back sectional view of the earth retaining structure according to the third embodiment when the gate is closed, and FIG. 15 is a side sectional view of the same. 16 is a cross-sectional view taken along the line CC in FIG. 15, and FIG. 17 is a back cross-sectional view when the gate is expanded. FIG. 18 is a side cross-sectional view of the same as above, and FIG. 19 is a side cross-sectional view showing the connection state between the gate steel plate and the hydraulic jack.

  The retaining structure 1C according to the third embodiment is similar to the retaining structures 1A and 1B according to the first and second embodiments. The steel pipe 3 in which the opening 6 is formed and the gate covering the opening 6 are used. A steel plate 7 and a water stop space 8 for preventing inflow of water and earth and sand into the steel pipe 3 are provided. In addition, the shape of the opening 6 is a circular shape having a size that allows the shield machine 2 to pass through, as in the second embodiment, and the steel pipe 3 has the same structure as that of the steel pipe 3 according to the second embodiment. It has become.

  The steel plate for gate 7 according to the present embodiment is a lift-type steel plate for gate that is provided in close contact with the inner peripheral surface of the steel pipe 3 and is slidable in the vertical direction. The steel plate 7 for a gate is a member having a reverse trapezoidal shape in front view or rear view curved with a curvature along the inner peripheral surface of the steel pipe 3, and in the direction Q for closing the opening 6 at both left and right edges. A movable wedge guide 26 having a tapered surface is provided so as to be narrowed. The movable wedge guide 26 is constituted by a single member integrated with the gate steel plate 7 formed over the entire length of the left and right edges of the gate steel plate 7.

  In addition, a water stop box 27 in which the water stop space 8 is formed is provided inside the steel pipe 3 so as to cover the range of movement of the gate steel plate 7 in the vertical direction. The water stop box 27 is a flat rectangular box-like member having a small depth dimension, and a circular opening 29 having a size through which the shield machine 2 can pass is provided on the back plate 28. Further, a fixed-side wedge formed with tapered surfaces on both sides of the water stop box 27 facing the left and right edges of the gate steel plate 7 so as to be constricted in the direction O in which the opening is expanded. A guide 30 is provided. The fixed-side wedge guide 30 is composed of a single member that is long in the vertical direction, like the movable-side wedge guide 26, and moves the gate steel plate 7 in the closing direction Q together with the movable-side wedge guide 26. It is a guide member to be made.

  Further, the water stop box 27 is configured to be divided into an upper water stop box 27A and a lower water stop box 27B, and both are connected by a connection bolt 43 to form one space communicating with the inside. It has come to be. Further, as shown in FIG. 19, the hydraulic jack 9 is mounted on the upper surface plate 34 of the upper water stop box 27 </ b> A, and a supporter support base 44 is provided at the tip of the slider 35 of the hydraulic jack 9. It has been. A supporter 46 that holds the upper end portion of the slide rod 45 extending upward from the upper surface of the gate steel plate 7 is attached to the supporter support base 44 by mounting bolts 47. It is possible to omit the supporter support base 44 and attach the supporter 46 directly to the slider 35. By doing so, the support rod support base 44 is omitted and the slide rod 45 is omitted. The stroke of can be taken longer.

  The slide rod 45 is provided in the middle so as to pass through the upper surface plate 34 of the upper water stop box 27A and project outside the water stop box 27. Since the water packing 36 is provided, a high water-stopping property of the water-stopping box 27 is maintained, and foreign matters are prevented from being mixed into the water-stopping box 27. Further, a water-stop packing 37 is also provided on the back surface 49 of the steel pipe 3 around the opening 6 that is in sliding contact with the front surface 48 of the gate steel plate 7 suspended by the slide rod 45. Inflow of water and earth and sand from a gap formed between the steel pipe 3 and foreign matter is prevented.

  The water stop box 27 is disposed after the steel pipe 3 is completely placed and the excavation and discharge of the earth and sand in the steel pipe 3 is completed. Therefore, also in this embodiment, the steel plate 7 for gates is temporarily fixed in a state of covering the opening 6 of the steel pipe 3 by using the fixing bolt 13 shown in FIG. Then, after the placement of the steel pipe 3 and the excavation and discharge of the earth and sand in the steel pipe 3 are completed, the fixing bolt 13 for temporary fixing is removed, and the upper water stop box 27A, the lower water stop box 27B, the hydraulic jack 9 are removed. The supporter 46, the slide rod 45, etc. are separately carried into the shaft and assembled in the state shown in FIG.

  And the earth retaining structure 1C which concerns on a present Example is constructed | assembled by driving all the steel pipes 3 to connect in the ground G. FIG. Moreover, since the earth retaining structure 1C constructed in this way has a compact shape that does not have a protruding portion on the outer peripheral surface, the structure is suitable for a shaft construction method using a rotary presser 4 with a small press-fitting resistance. It has become. In the present embodiment, the gate steel plate 7 is provided on the inner peripheral surface side of the steel pipe 3, so that the external soil water pressure is directly applied to the gate steel plate 7. Therefore, although there is a concern about securing water stoppage, a high water stoppage is achieved by the wedge action by the water stop box 27, the movable side wedge guide 26 and the fixed side wedge guide 30, and the two types of water stop packings 36 and 37. Aqueousness is secured.

  In addition, about the retaining structure 1C which concerns on a present Example (2) About the construction method of the retaining structure, it basically concerns on the said Example 1 and Example (2) Construction of the retaining structure Although it is the same as the method, in addition to (a) primary steel pipe placing process and (b) continuous steel pipe placing process, (c) water stop box installing process is provided. The (c) water stop box installation step is a step in which members such as the water stop box 27, the hydraulic jack 9 and the slide rod 45 are installed and assembled inside the steel pipe 3A in which the opening is formed.

  In addition, the (3) shield machine start-up method for the earth retaining structure 1C according to the present embodiment is basically the same as the (3) shield machine start-up method according to the first and second embodiments. However, (c) when the gate steel plate 7 is slid in the expansion direction O in the gate steel plate expansion step, the filler M in the water stop space 8 is discharged to the outside in the first and second embodiments. In this embodiment, the gate steel plate is released while the wedge action of the movable side wedge guide 26 and the fixed side wedge guide 30 is released. 7 differs in that it is configured to enter and be accommodated in the upper part of the water stop box 27 in which the water stop space 8 is provided. In addition, detailed description here is abbreviate | omitted about the structure similar to the construction method of (2) earth retaining structure of Example 1 and Example 2 mentioned above, and (3) the start arrival construction method of a shield machine.

[Example 4]
(1) Structure of earth retaining structure (see FIGS. 20 to 25)
20 is a back cross-sectional view of the earth retaining structure according to the fourth embodiment when the gate is closed, and FIG. 21 is a cross-sectional view taken along the line DD in FIG. 22 is a back sectional view when the gate is expanded, and FIG. 23 is a sectional view taken along the line E-E in FIG. FIG. 24 is a plan view of the steel pipe in the same manner as in FIG. 24. FIG. 25 shows the start procedure of the start reaching method of the shield machine when the earth retaining structure according to the fourth embodiment is used. It is a plane sectional view divided and shown in three steps.

  The earth retaining structure 1D according to the fourth embodiment covers the steel pipe 3 in which the opening 6 is formed and the opening 6 similarly to the earth retaining structures 1A, 1B, and 1C according to the first to third embodiments. The steel plate 7 for gates and the water stop space 8 which prevents inflow of the water and earth and sand into the steel pipe 3 are provided. Further, the retaining structure 1D according to the fourth embodiment includes a water stop box 31 in which a water stopping space 8 is formed, like the retaining structure 1C according to the third embodiment. In addition, about the steel pipe 3, it is the same as that of the steel pipe 3 of the said Example 2 and Example 3, and the circular opening part 6 of the magnitude | size which can pass the shield machine 2 is formed.

  The gate steel plate 7 according to the present embodiment is a laterally slidable gate steel plate that is provided in close contact with the inner peripheral surface of the steel pipe 3 and is slidable in the left-right direction. The steel plate for gate 7 is a member having a square shape in front view curved with a curvature along the inner peripheral surface of the steel pipe 3, and the back surface of the steel plate for gate 7 is constricted in a direction Q for closing the opening 6. A movable-side wedge guide 33 is provided which is composed of a total of six cotter receivers 32 each having three tapered upper and lower tapered surfaces. Note that the three cotter receivers 32 provided in the upper and lower directions are arranged so as to be shifted in the vertical direction, and gradually approach each other in the direction Q in which the upper and lower cotter receivers 32 close the opening 6. Are arranged as follows.

  In addition, the water stop box 31 described above in which the water stop space 8 is formed is provided inside the steel pipe 3 so as to cover the moving range of the gate steel plate 7 in the left-right direction. This water stop box 31 is a flat rectangular box-shaped member having a small depth dimension, and has a long shape in the left-right direction curved with a curvature along the inner peripheral surface of the steel pipe 3. In addition, the back plate 38 of the water stop box 31 is provided with a circular opening 39 large enough to allow the shield machine 2 to pass through, and the inner peripheral surfaces of the upper surface plate and the lower surface plate of the water stop box 31 are provided. A guide surface 40 is provided for guiding the sliding operation of the gate steel plate 7 in the left-right direction.

  In addition, the inner surface of the water stop box 27 that faces the back surface of the gate steel plate 7 when the gate is closed is formed with tapered surfaces formed so as to be constricted in the direction O in which the opening 6 is expanded. A fixed-side wedge guide 42 constituted by six cotters 41 in total is provided. The six cotters 41 are respectively disposed at positions facing the six cotter receivers 32 described above. The fixed-side wedge guide 42 thus configured is a guide member that moves the gate steel plate 7 in the closing direction Q together with the movable-side wedge guide 33.

  In addition, the water stop box 31 is installed after the completion of the casting of the steel pipe 3 and the completion of excavation and discharge of earth and sand in the steel pipe 3. Also in this embodiment, the gate steel plate 7 is temporarily fixed in a state in which the opening 6 of the steel pipe 3 is covered by using a fixing bolt 13 or the like as shown in FIG. In addition, after the placement of the steel pipe 3 is completed and the excavation and discharge of the earth and sand in the steel pipe 3 is completed, the hydraulic jack 9 (not shown) is connected to the back plate 38 of the water stop box 31 as in the first to third embodiments. Etc. are attached between the inner peripheral surface of the steel pipe 3 and the back surface of the gate steel plate 7, and the fixing bolt 13 for temporary fixing described above is also removed. Although not shown, a water stop packing 36 is provided on the back plate 38 of the water stop box 31 that is in sliding contact with the slider 35 of the hydraulic jack 9, as in the third embodiment. Together with the water stop packing 37 provided on the back surface of the steel pipe 3 around the opening 6 that is in sliding contact with the steel plate 7, it contributes to the improvement of water stop and prevents the entry of foreign matter.

  And the earth retaining structure 1D which concerns on a present Example is constructed | assembled by driving all the steel pipes 3 connected in the ground G. FIG. Moreover, since the earth retaining structure 1D constructed in this way has a compact shape having no protrusions on the outer peripheral surface, the structure is suitable for a shaft construction method using a rotary presser 4 with low press-fitting resistance. ing. In the present embodiment, as in the third embodiment, the gate steel plate 7 is provided on the inner peripheral surface side of the steel pipe 3, so that the external soil water pressure is directly applied to the gate steel plate 7. Therefore, although there is a concern about securing water stoppage, the water stop box 31, the wedge action by the movable side wedge guide 33 and the fixed side wedge guide 42, and the two types of water stop packings 36 and 37 are high. Waterproofness is ensured.

  In addition, about the retaining structure 1D which concerns on the present Example (2) About the construction method of the retaining structure, it is the same as that of the construction method of the retaining structure (2) which concerns on the said Example 3 in outline. Yes, it is constructed by three processes: (a) primary steel pipe placing process, (b) continuous steel pipe placing process, and (c) water stop box installing process. Therefore, the detailed description here is omitted.

  Also, the (3) shield machine start reaching method for the earth retaining structure 1D according to the present embodiment is also substantially the same as the (3) shield machine start reaching method according to the third embodiment. Therefore, here, the description will be limited to (c) the steel plate expansion process for gates, which is different from the configuration of Example 3, (a) entrance installation process, (b) pressure balance adjustment process, and (d) shield machine start arrival. Detailed description of the process is omitted.

(C) Steel plate expansion process for gate (refer to FIG. 8 (c), FIG. 25 (a) to FIG. 25 (c))
In the gate steel plate expansion step, the contact state between the fixed wedge guide 42 and the movable wedge guide 33 is released by sliding the gate steel plate 7 in the expansion direction O, thereby expanding the opening 6. It is the process of making it an open state. That is, while maintaining a pressure balance between the chamber pressure in the chamber 23 and the external soil water pressure at the entrance 20, the hydraulic jack 9 (not shown) is operated to open the gate steel plate 7 in the expanding direction O (in FIG. 25, Slide left). The steel plate for gate 7 is guided by the upper and lower guide surfaces 40 of the water stop box 31 and enters the water stop space 8 formed on the left side in FIG. The contact state between the guide 33 and the fixed-side wedge guide 42 is released. Then, when the gate steel plate 7 is completely accommodated in the water-stopping space 8, the opening 6 is in an expanded state, and the shield machine 2 shown in FIG. The shield machine 2 (not shown) can be reached.

[Other embodiments]
The earth retaining structure 1 using the steel pipe 3 according to the present invention, the construction method of the earth retaining structure 1, and the start-up construction method of the shield machine 2 using the earth retaining structure 1 are configured as described above. Although it is based, it is of course possible to change or omit a partial configuration within a range not departing from the gist of the present invention. For example, the press-fitting machine for press-fitting the steel pipe 3 is not necessarily the rotary press-fitting machine 4 and may be a swing press-fitting machine. In the description of the first to fourth embodiments, the description has been made centering on the case where the shield machine 2 is started from the start shaft in the description of the start-up method of the shield machine 2, but the shield machine 2 is used for reaching. The same applies to the case of reaching the shaft.

  However, when the shield machine 2 is made to reach the arrival shaft, the earth and water pressure in the ground G where the shield machine 2 being excavated exists, and the chamber pressure in the chamber 23 at the entrance 20 in the arrival shaft to be reached from now on, However, it is possible to cope with this by adopting a known method such as freezing (Japanese Patent Laid-Open No. 2004-270252). Further, in the case of the earth retaining structures 1A and 1B according to the first and second embodiments, the water-stopping packing 37 is illustrated for the steel pipe 3 around the opening 6 that is in sliding contact with the gate steel plate 7. Although there is no, it is possible to provide the water stop packing 37 similarly to the earth retaining structures 1C and 1D according to the third and fourth embodiments.

  Moreover, the movable-side wedge guide 26 and the fixed-side wedge guide 30 employed in the retaining structure 1C according to the third embodiment are used as the retaining structures 1A and 1B according to the first and second embodiments. It is also possible to provide the movable-side wedge guide 33 and the fixed-side wedge guide 42 employed in the earth retaining structure 1D according to the present invention, and the earth retaining structures 1A, 1B, 1C according to the first to third embodiments. It is also possible to make each gate steel plate 7 into a horizontal slide type, or to change each gate steel plate 7 of the retaining structure 1D according to Example 4 to a lifting type. In addition, instead of the fixing bolt 13 for temporary fixing, other fastening means, clamping means, and engaging means may be employed, or temporarily fixed by gas welding or electric welding, and then a gas burner or the like. It is also possible to release the temporarily fixed state by fusing the welded part using the.

  The present invention can be used at a construction site of a shaft using a steel pipe, a shield construction site where the shaft is used as a starting shaft or a reaching shaft, etc., and in particular, it is desired to press the steel pipe deeper using a rotary press-fitting machine. In this case, there is applicability when it is desired to improve water-stopping with a simple structure, or when it is desired to start and reach the shield machine directly without performing troublesome work such as ground improvement.

It is a sectional side view which shows the construction state which press-sinks the earth retaining structure using a rotary press-fitting machine. It is a sectional side view at the time of gate closure which shows the earth retaining structure concerning Example 1. It is a front view at the time of gate closure which shows the earth retaining structure concerning Example 1. It is AA sectional drawing in FIG. 3 which shows the earth retaining structure which concerns on Example 1. FIG. It is a sectional side view at the time of gate expansion which shows the earth retaining structure which concerns on Example 1. FIG. It is a front view at the time of the gate expansion which shows the earth retaining structure which concerns on Example 1. FIG. It is a sectional side view which shows the construction procedure of the construction direction of the earth retaining structure of this invention. It is a sectional side view which shows the start procedure of the start arrival construction method of the shield machine of this invention. It is a sectional side view at the time of gate closure which shows the earth retaining structure concerning Example 2. It is a front view at the time of gate closure which shows the earth retaining structure concerning Example 2. It is BB sectional drawing in FIG. 10 which shows the earth retaining structure concerning Example 2. FIG. It is a sectional side view at the time of gate expansion which shows the earth retaining structure which concerns on Example 2. FIG. It is a front view at the time of gate expansion which shows the earth retaining structure which concerns on Example 2. FIG. It is a back sectional view at the time of gate closure showing the earth retaining structure concerning Example 3. It is a sectional side view at the time of gate closure which shows the earth retaining structure concerning Example 3. It is CC sectional drawing in FIG. 15 at the time of the gate obstruction | occlusion which shows the earth retaining structure which concerns on Example 3. FIG. It is a back sectional view at the time of gate expansion which shows the earth retaining structure concerning Example 3. It is a sectional side view at the time of the gate expansion which shows the earth retaining structure concerning Example 3. It is a sectional side view which expands and shows the connection state of the steel plate for gates of the earth retaining structure which concerns on Example 3, and a hydraulic jack. It is a back sectional view at the time of gate closure showing the earth retaining structure concerning Example 4. It is DD sectional drawing in FIG. 20 at the time of the gate obstruction | occlusion which shows the earth retaining structure which concerns on Example 4. FIG. It is a back sectional view at the time of gate expansion which shows the earth retaining structure concerning Example 4. It is EE sectional drawing in FIG. 22 at the time of gate expansion which shows the earth retaining structure which concerns on Example 4. FIG. It is a plane sectional view showing the state where the steel plate for gates was temporarily fixed to the steel pipe so as to cover the opening. It is a plane sectional view which shows the start procedure of the start arrival construction method of the shield machine at the time of using the earth retaining structure which concerns on Example 4. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Earth retaining structure, 2 Shield machine, 3 Steel pipe, 4 Rotary press-fit machine, 5 circumference body part, 6 Opening part (gate), 7 Gate steel plate, 8 Water stop space, 9 Hydraulic jack, 10 Joint, 11 Inner steel plate, 12 Cutting edge, 13 Fixing bolt, 14 Double steel pipe part, 15 Thin steel plate, 16 Opening part, 17 Discharge port, 18 Wellhead concrete, 19 Packing, 20 Entrance, 21 Face, 22 Cutter face, 23 Chamber, 24 Outer steel plate, 25 Opening, 26 Movable side wedge guide, 27 Water stop box, 27A Upper water stop box, 27B Lower water stop box, 28 Back plate, 29 Opening, 30 Fixed side wedge guide, 31 Water stop box, 32 cotter receiver, 33 Movable wedge guide, 34 Top plate, 35 Slider, 36 Water seal packing, 37 Water seal packing, 38 Back plate, 39 opening, 40 guide surface, 41 cotter, 42 fixed wedge guide, 43 connecting bolt, 44 supporter support base, 45 slide rod, 46 supporter, 47 mounting bolt, 48 front, 49 back, G ground, D Friction cut amount, M filler, O direction of spreading (to make it happen), direction of closing (to make it Q)

Claims (10)

A structure for earth retaining formed by placing a steel pipe in the ground,
A steel pipe in which an opening for passing a shield machine is formed in a part of the peripheral body,
A slidable steel plate for a gate addressed to close the opening; and
A water stop space for preventing inflow of water and earth and sand from the outside into the steel pipe,
When expanding the steel plate for the gate, using the water stop space as a storage space for storing the steel plate for the gate ,
The structure for earth retaining is provided with a joint for connecting the steel plate for the gate to the steel pipe,
The steel plate for the gate is provided on the same circumference as the steel pipe so as to coincide with the outer peripheral surface of the steel pipe, and the joint and the inner steel plate are in close contact with the inner peripheral surface of the steel pipe inside the steel pipe. A dough retaining structure using a steel pipe, wherein a double steel pipe portion having no protrusion is formed on the outer peripheral surface . In the earth retaining structure having the steel pipe according to claim 1,
The structure for earth retaining is provided with a joint for connecting the steel plate for the gate to the steel pipe,
The steel plate for a gate and the joint are provided in a protruding state outward of the outer peripheral surface of the steel pipe, and outside the outer peripheral surface of the steel pipe in which the steel plate for gate and the joint are not provided, Using a steel pipe characterized in that a double steel pipe part is formed in which the outer steel sheet is arranged in close contact so as to coincide with the outer peripheral surface of the gate steel sheet and the joint, and the outer peripheral surface does not have a protrusion. Earth retaining structure. In the earth retaining structure using the steel pipe according to claim 1 or 2 ,
The water stop space is formed in a space defined by the steel pipe, the gate steel plate, the inner steel plate or the outer steel plate, and a thin iron plate addressed to the remaining opening surface, and the gate steel plate. In the initial state in which the filler is filled in the water stop space, the filler is discharged from the outlet formed in the thin iron plate when the gate steel plate is shifted to the expanded state. An earth retaining structure using a steel pipe, characterized by being configured to be discharged to the outside. In the earth retaining structure having the steel pipe according to claim 1,
The steel plate for a gate is a lift-type steel plate for a gate that is slidable in the vertical direction provided in close contact with the inner peripheral surface of the steel pipe, and the left and right edges of the steel plate for gate A movable-side wedge guide having a tapered surface formed so as to be narrowed in the direction of closing the opening is provided,
Inside the steel pipe is provided with a water stop box in which the water stop space is formed so as to cover the moving range of the gate steel plate,
A fixed-side wedge guide having a tapered surface formed so as to be narrowed in the direction of expanding the opening is provided on both sides of the water stop box facing the left and right edges of the gate steel plate. The steel plate for the gate is guided by the movable-side wedge guide and the fixed-side wedge guide that are in sliding contact with each other in the water stop box, and is configured to close the opening. The earth retaining structure used. In the earth retaining structure having the steel pipe according to claim 1,
The steel plate for a gate is a laterally slidable steel plate for a gate that is slidable in the left-right direction provided in close contact with the inner peripheral surface of the steel pipe, and the opening is formed on the back surface of the steel plate for the gate A movable-side wedge guide having a tapered surface formed so as to be constricted in the closing direction is provided,
Inside the steel pipe is provided with a water stop box in which the water stop space is formed so as to cover the moving range of the gate steel plate,
A fixed-side wedge guide having a tapered surface formed so as to be narrowed in the direction of expanding the opening is provided on the inner surface of the water stop box facing the back surface of the steel plate for the gate. A steel retaining structure using a steel pipe, wherein the steel plate is guided by the movable-side wedge guide and the fixed-side wedge guide that are in sliding contact with each other in the water stop box, and is configured to close the opening. body. It is a construction method of a retaining structure that forms a structure for retaining earth by driving it into the ground while connecting a plurality of steel pipes,
The steel pipe according to claim 3 , wherein an opening for passing a shield machine is formed in a part of the peripheral body, the opening is closed with a steel plate for a gate, and a filler is filled in the water stop space. A primary steel pipe placing process in which the steel pipe is placed in the ground using a press-fitting machine,
Using another steel pipe that does not have an opening in the peripheral body, and a continuous steel pipe placing step in which the other steel pipe is continuously placed in the ground using a press-fitting machine. A method for constructing a retaining structure, characterized by comprising: It is a construction method of a retaining structure that forms a structure for retaining earth by driving it into the ground while connecting a plurality of steel pipes,
6. The steel pipe according to claim 4 or 5 , wherein an opening for passing a shield machine is formed in a part of the peripheral body, the opening is closed with a gate steel plate, and the fixed-side wedge guide and the movable-side wedge are closed. A primary steel pipe placing step of placing the steel pipe into the ground using a press-fitting machine in a state where the guide is in contact with and in close contact with the guide;
Using another steel pipe that does not have an opening in the peripheral body, a continuous steel pipe placing process in which the other steel pipe is continuously placed in the ground using a press-fitting machine,
The construction method of the earth retaining structure characterized by including the water stop box installation process which installs the said water stop box inside the steel pipe in which the said opening part was formed. In the construction method of the earth retaining structure according to claim 6 or 7 ,
The press-fitting machine is a rotary press-fitting machine that can be placed in the ground while rotating the steel pipe all around. In the primary steel pipe placing process and the continuous steel pipe placing process, the steel pipe is rotated in the ground while rotating all around. A method for constructing a retaining structure, characterized in that it is placed on the ground. After the retaining structure using the steel pipe according to claim 3 is constructed by the construction method of the retaining structure according to claim 6 or 8 , the retaining structure is used as a starting shaft or a reaching shaft. The shield machine start-up construction method for starting and reaching the shield machine with the opening in an expanded state,
An entrance installation step of installing an entrance with wellhead concrete and packing in the double steel pipe portion around the opening;
A pressure balance adjusting step that balances the chamber pressure in the entrance with the earth and water pressure outside the double steel pipe portion to obtain a pressure balance;
The gate steel plate is caused to slide into the water stop space by sliding the gate steel plate in the expanding direction, and the filler in the water stop space is discharged to the outside from the discharge port formed in the thin iron plate. While expanding the steel plate for the gate to expand the opening,
A shield machine start and reach method comprising a shield machine start and reach step of starting or reaching the shield machine directly from the expanded opening. After the earth retaining structure using the steel pipe according to claim 4 or 5 is constructed by the construction method of the earth retaining structure according to claim 7 or 8 , the earth retaining structure is used as a starting shaft or a reaching shaft. As a shield machine start-up construction method for starting and reaching the shield machine with the opening in an expanded state,
An entrance installation step of installing an entrance with wellhead concrete and packing in the steel pipe around the opening;
A pressure balance adjusting step that balances the chamber pressure in the entrance with the soil water pressure outside the steel pipe to balance the pressure;
A gate steel plate expanding step for releasing the contact state between the fixed-side wedge guide and the movable-side wedge guide by sliding the gate steel plate in the expanding direction, and bringing the opening into an expanded state;
A shield machine start and reach method comprising a shield machine start and reach step of starting or reaching the shield machine directly from the expanded opening.

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