JP2009114644A - Open shield method and open shield machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an open shield method capable of adapting to each construction method by preparing a plurality of open shield machines for each construction method without replacing them, even if the construction method is changed midway through construction; and to provide the open shield machine. <P>SOLUTION: Backfill grouting is applied to the periphery of an underground structure placed on a bottom plate 20, in a state in which the bottom plate 20 is mounted on a tail section 1c on a construction site requiring the backfill grouting for the periphery of the underground structure. The underground structure is directly placed on the excavated underground structure so that the periphery of the underground structure can be backfilled with sediment, in a state in which the bottom plate 20 is detached on a construction site dispensing with the backfill grouting. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an open shield machine and an open shield method for constructing an underground structure such as an attached underground passage such as a water and sewage system, a common ditch, a telegraph / telephone, and a passenger car road.

The open shield method is widely used as a method for constructing underground structures such as water and sewage systems, common ditches, telegraphs and telephones, and other underground structures. The open shield method is a highly rational method utilizing the advantages of the open cut method (open cut method) and the shield method. For example, the following patent documents relating to the open shield method exist.
JP 2006-112101 A JP 2006-112100 A

  As shown in FIG. 19, the outline of the open shield machine 1 used in this open shield construction method basically includes a front surface, a rear surface, and an upper surface composed of left and right side wall plates 1a and a bottom plate 1b connected to the side wall plates 1a. The front end of the side wall plate 1a and the bottom plate 1b is formed as a blade edge 11 with an opening, and the propulsion jacks 2 are arranged side by side up and down at the center or near the rear end of the side wall plate 1a. In the figure, 3 indicates a partition wall.

  The open shield method to be constructed using such an open shield machine 1 is not shown in the figure, but this open shield machine 1 is installed in the start pit, and the propulsion jack 2 of the open shield machine 1 is extended so that the The open shield machine 1 is moved forward with the reaction force against the reaction wall, the first concrete box 4 forming the underground structure is suspended from above, and the propulsion is shrunk in the tail portion 1c of the open shield machine 1 Set behind jack 2. A strut is disposed between the propulsion jack 2 and the reaction wall to adjust the distance appropriately.

  In addition, the start pit is made up of a retaining wall, and in order to start the open shield machine 1, a part of this retaining wall is mirror-cut. If necessary, the ground is improved at the front part of the starting pit by chemical injection or the like. Sometimes it is left.

  Excavator 9 such as an excavator excavates and removes soil from the front or upper surface of open shield machine 1. At the same time as or after this earth removal step, the propulsion jack 2 is extended to advance the open shield machine 1. In this advancement process, a press bar 8 made of a frame made of box steel or mold steel is arranged in front of the concrete box 4, and the open shield machine 1 reacts from the concrete box 4 set on the rear side. Take.

  Then, the second concrete box 4 is suspended in the tail portion 1 c of the open shield machine 1 in front of the first concrete box 4. Thereafter, the same soil removal process, advance process, and setting process of the concrete box 4 are repeated as appropriate, and the concrete boxes 4 are sequentially left in the ground in line with the advancement of the open shield machine 1, and further this concrete box. Put backfill 5 on the upper surface of 4.

  When the concrete box 4 is suspended in the tail part 1c of the open shield machine 1, a height adjusting material 7 such as a concrete block is disposed under the concrete box 4, and the concrete part 4 is placed in the tail part 1c. The grout material 6 is filled in the left and right and lower spaces of the box 4.

  In this way, if the open shield machine 1 reaches the reaching mine, it is removed and the construction is completed.

  In such an open shield construction method, as described above, the concrete box 4 is left in the ground in a column as the open shield machine 1 advances, and the concrete box 4 is suspended in the tail portion 1c of the open shield machine 1. As the open shield machine 1 moves forward, it leaves the tail portion 1c and remains in the ground. The open shield machine 1 takes a reaction force on the concrete box 4 left in the ground in this way. Advance.

  In addition to the open shield machine 1, as shown in FIG. 20, the machine body is divided into a plurality of parts in the front-rear direction, and the front end of the rear machine body as the tail part 1c is slightly reduced in cross-sectional area. There are some which are fitted at the rear end of the front machine body and can be bent at the middle bent portion 1e as a mutual fitting portion.

  This has a front end and an upper surface of the front body as the front portion 1d as open surfaces, and the folded jacks 30 are arranged on the left and right and rearward and rearward in a plurality of stages in the vertical direction. . On the other hand, the tail portion 1c has the propulsion jacks 2 arranged on the left and right sides and in a plurality of upper and lower stages toward the front and rear in the body. In the figure, 50 is a movable split blade provided at the front end of the front portion 1d, 51 is a rear retaining plate provided at the rear end of the tail portion 1c, 34 is a strut, and 8 is a press bar (push angle).

  In any of the shield machines, the concrete box 4 to be used is made of reinforced concrete, and as shown in FIG. 21, it is an integral unit composed of a left side plate 4a, a right side plate 4b, an upper floor plate 4c, and a lower floor plate 4d. Is opened as an opening 10.

  By the way, when the concrete box 4 is placed on the bottom plate 1b of the tail portion 1c as described above, for example, even if the ground at the construction site is a soft clay soil, the influence of the heaving is caused by the presence of the bottom plate 1b. There is no worry to receive. Moreover, even if it is sandy ground with a high groundwater level, there exists an advantage that there is no worry of being influenced by boiling by presence of the baseplate 1b.

  Further, as described above, when the grout material 6 is filled in the left and right and lower spaces of the concrete box 4 in the tail portion 1c of the open shield machine 1 as the backfilling material, the concrete box is formed by the fixed grout material 6. The periphery of 4 is hardened and stabilized, and further, infiltration of groundwater into the concrete box 4 can be prevented. Therefore, the construction method (backfill injection type) that excavates while performing such backfill injection has the advantage of being able to cope with a wide range of soil conditions from high groundwater levels to soft and unstable ground.

  In addition, since the backfilling work for filling the left and right and lower gaps of the laid concrete box 4 is unnecessary, it is not necessary to transport a large amount of earth and sand from the surroundings for the backfilling work, and the backfilling work is accompanied. Since noise can also be suppressed, it is suitable for construction where there is a need to minimize the influence of the surrounding area such as near the house.

  However, when the construction distance is long, there are many places where construction conditions are different, such as a place where the ground is stable and a place where the ground is unstable. In order to perform construction efficiently and economically with sufficient consideration for the surrounding environment, construction according to the conditions of the construction site is required.

  For example, in a stable ground that is less affected by groundwater and is self-supporting, there is no need for backfill injection around the concrete box, rather than backfill injection when there are few nearby structures. Instead, it may be preferable to refrain from using the grout material 6 by digging while filling back the left and right voids of the installed concrete box 4.

  In such a case, an open shield machine without the bottom plate 1b is used as an open shield machine for the construction method (no backfill injection type) to dig without backfill injection, and suspended in the tail portion 1c. The concrete box 4 is placed directly in the excavation hole.

  Thus, when the construction method differs depending on the conditions of the construction site, it is necessary to use the open shield machine used for each construction site.

  However, if an open shield machine is prepared for each construction method, a large number of open shield machines are required, which is uneconomical.

  Also, if you try to replace the open shield machine during construction, you must keep the earth shield by driving a sheet pile around the open shield machine in order to prevent the earth and sand retained by the side shield of the open shield machine from collapsing. Furthermore, since the open shield machine is carried out and carried in the excavation hole, a lot of labor and labor are required.

  In addition, the open shield method is often applied to places where it is possible to cut, but earthing with a sheet pile is difficult. In such cases, the open shield machine is earthed with a sheet pile to open shield. It is impossible to change the machine itself.

  The purpose of the present invention is to eliminate the disadvantages of the conventional example, and even if the construction method is changed during construction, each construction method is prepared without replacing a plurality of open shield machines for each construction method. It is to provide an open shield method and an open shield machine that can comply with the law.

  In order to achieve the above object, the open shield construction method of the present invention is firstly provided with a propulsion jack in the shield machine having the front and rear ends and the upper surface comprising the left and right side wall plates and the bottom plate connected to the side wall plates. Excavating and discharging the soil in front of the front or front upper surface with an excavator, and extending the propulsion jack and advancing the shield machine by using the existing underground structure such as a concrete box following the reaction force In the open shield method of burying underground structures in tandem one after another, the process of setting a new underground structure behind the propulsion jack shrunk in the tail part of the shield machine is repeated, and backfilling around the underground structure At construction sites that require injection, with the bottom plate attached to the tail, backfill injection is performed around the underground structure placed on the bottom plate, and backfill injection is required. In the treated region not in a state of detaching the bottom plate, it is an Abstract that backfill sand therearound by placing the underground construction directly drilled on ground.

  Or, in construction sites where the ground is unlikely to collapse, with the bottom plate removed from the tail, place the underground structure directly on the excavated ground and backfill the surrounding soil, and in construction sites where the ground is likely to collapse , With the bottom plate attached to the tail and the front part of the shield machine covered with a closing wall, the underground structure is suspended on the bottom plate and backfilling is performed around the underground structure; The gist is to repeat a step of excavating and discharging the inside of the enclosed space by the wall and the front portion, and a step of removing the closed wall and advancing the shield machine.

  As an open shield machine of the present invention, first, a shield machine having front and rear ends and an upper surface composed of left and right side wall plates and a bottom plate connected to the side wall plates, the propulsion jacks are arranged rearward in the rear tail portion. In the open shield machine arranged side by side up and down, the bottom plate of the tail part is detachably arranged so that an underground structure can be placed on the bottom plate of the tail part, and on the excavated ground The gist is to select and use a bottom plate separation state in which an underground structure can be directly placed.

  Secondly, at the lower ends of the left and right side wall plates of the tail portion, the left and right side edges of the bottom plate are detachably joined, or an inwardly extending portion is provided at the lower end of the left and right side wall plates of the tail portion, and the tip of the protruding portion The gist of the present invention is to removably join the left and right side edges of the bottom plate.

  Thirdly, the gist is to provide a movement restricting means for restricting the movement of the bottom plate to the rear of the tail portion between the joint portion of the bottom plate and the side wall plate or between the bottom plate and the front portion of the tail portion. It is.

  And fourthly, a partition that is disposed between the left and right side wall plates and slidable forward and backward is provided, or a partition that is disposed between the left and right side wall plates and divides the body forward and backward. Can be opened or closed, or the partition that is arranged between the left and right side wall plates and divides the aircraft body in the front and back is configured in two upper and lower stages, the upper partition can be opened and closed, and the lower partition is the bottom of the existing water channel The gist is that the height can be adjusted according to the above.

  Further, the fifth aspect is to dispose the closing wall in the width direction of the open shield machine in a detachable manner in front of the front portion.

  According to the present invention described in claim 1, when there is a construction site by a different type of construction method between the backfill injection type and the backfill no injection type within the construction range, and the construction method is changed during the construction. Even if you do not prepare multiple open shield machines for each construction method and replace them, only by attaching and detaching the bottom plate, you can support both different types of construction methods, backfill injection type and backfill no injection type. be able to.

  In this way, it is economical because it is not necessary to prepare multiple open shield machines for each construction method, and it is not necessary to replace open shield machines during construction, so efficient construction is possible. It becomes.

  According to the second aspect of the present invention, the ground where the back-filling type construction is necessary within the construction range is easy to collapse, and the ground where the back-filling-free construction is possible is difficult to collapse and When the construction method is changed during construction, there is no need to replace multiple open shield machines for each construction method. It is possible to correspond to both types of construction methods different from the non-injection type.

  Furthermore, in construction sites where the ground is likely to collapse, with the bottom plate attached to the tail and the front part of the open shield machine covered with a closed wall, the underground structure is suspended from the tail and its surroundings. Because of the back-filling injection, there is no influence of heaving during the work due to the presence of the bottom plate, and due to the presence of the closing wall, the natural ground in front of the shield machine collapses during the work and swallows into the front part. There is no progress in the collapse of the surrounding ground.

  And in that state, the process of excavating and discharging the enclosed space and the inside of the front part can empty the front part while preventing the collapsed earth and sand from flowing into the front part from the front part of the front part. In this way, when the shield machine is advanced after removing the closing wall in the next step, it is possible to prevent the propulsion thrust from increasing due to earth pressure of the earth and sand accumulated in the front portion.

  Moreover, since the front part of the front part is continuously covered with the closing wall except when the open shield machine is moving forward, the front part of the front part is open for a short time, and the surrounding ground does not collapse during that time.

  And since these can be realized only by attaching and detaching the bottom plate and placing / removing the closing wall, it is suitable for each construction site without preparing a separate open shield machine for each construction method and replacing it during the construction. It can correspond to the construction method. For this reason, economical and efficient construction is possible.

  According to the third aspect of the present invention, since the bottom plate on which the concrete box is placed is detachably attached to the tail portion, the open shield machine can be used without attaching the bottom plate at a place where backfill injection is not required. By using, the concrete box suspended from the tail part can be directly placed in the ground. In places where backfilling is required, a bottom plate is attached to the tail, so that the concrete box suspended from the tail is temporarily placed on the bottom plate and backed around the concrete box in the tail. An injection can be performed.

  In this way, by only attaching and detaching the bottom plate, it is possible to correspond to both different types of construction methods, backfill injection type and backfill no injection type, without having to prepare multiple open shield machines for each construction method Economical.

  In addition, even when there are construction sites with different construction methods within the construction range, it is possible to cope with each construction method only by attaching and detaching the bottom plate, and it is possible to efficiently construct without replacing the open shield machine during construction. it can.

  According to the fourth aspect of the present invention, since the left and right side edges of the bottom plate are detachably joined at the lower ends of the left and right side wall plates of the tail portion, the left and right sides of the bottom plate are stably supported at the lower ends of the side wall plates. Thus, the load of the concrete box placed on the bottom plate can be firmly supported.

  In addition, by fixing the left and right side edges of the bottom plate to the tail portion, it is not necessary to provide further joining means on the rear end side of the bottom plate. By such joining means on the rear end side of the bottom plate, the bottom plate is removed from the tail portion. When the open shield machine is used after being removed, the movement of the underground structure in the tail portion to the rear of the tail portion is not hindered.

  According to the fifth aspect of the present invention, as in the second aspect of the present invention, the bottom plate is supported on the left and right sides at the lower end of both side wall plates, and the concrete box placed on the bottom plate is placed. The load can be firmly supported, and the workability can be prevented from being hindered by further providing the joining means on the rear end side of the bottom plate.

  In addition, when using the open shield machine with the bottom plate removed, the presence of the overhanging portion at the lower end of the side wall plate can increase the contact area of the tail to the ground, even on relatively soft ground. The sinking of the open shield machine due to the weight of the open shield machine can be reduced.

  According to the sixth aspect of the present invention, since the movement of the bottom plate to the rear of the tail portion is restricted, the propulsion jack is extended by using the underground structure placed on the bottom plate as a reaction force to propel the open shield machine. In doing so, as the underground structure moves relative to the rear of the open shield machine, the bottom plate is also dragged rearward, so that it does not fall out behind the tail part together with the underground structure.

  According to the seventh aspect of the present invention, even if the construction range includes a portion of geology that tends to collapse, and excavation and soil removal and advancement are not performed smoothly, the partition wall is slid forward to within the front portion. By pushing out the earth and sand in the front, the sand in the front part and its front is consolidated, making it difficult to collapse the sand in front of the front part and making it easy to excavate and remove the earth and sand in the front part and its front It becomes possible to comply with the law.

  In addition, if this partition is not moved, it can respond to the normal construction method which does not require the further compaction of the earth and sand in a front part.

  In addition, if there is an existing waterway partially in the construction area, such as renovation or extension of the existing waterway, if there is a heavy rain during the construction period, the water that flows into the waterless waterway that has been dammed will become a running water, There is a risk that it will flow into the open shield machine and be blocked by the bulkhead and accumulate at the front of the open shield machine and overflow and cause a very dangerous situation. In addition, in order to keep the existing waterway closed during the construction period, it is necessary to secure a separate drainage route. However, it takes a lot of labor and it may be difficult to secure the drainage route. Therefore, in such a case, a construction method for flowing the water in front of the open shield machine backward is necessary.

  According to the present invention described in claim 8, when it is necessary to discharge during the repair of the existing water channel portion, the whole shield machine has a U-shaped cross section by opening the partition wall with the bottom plate attached to the tail portion. It can be adapted to the construction method of sending water to the back of the open shield machine.

  And in cases other than the above, by closing the partition wall, it is possible to cope with the construction method of retaining the soil with the partition wall as usual.

  In refurbishment and extension of existing waterways, new waterways may be deeper than existing waterways. In such cases, there is running water in the open shield machine from the front due to heavy rain, etc. When it is necessary to flow, a construction method is required in which the lower portion of the existing water channel is earthed while flowing the water backward.

  According to the ninth aspect of the present invention, in such a case, with the bottom plate attached to the tail portion, the upper partition is opened and the open shield machine is used as a trough while the water flows behind the open shield machine. In addition, it is possible to perform a construction method in which the upper end position of the lower partition wall whose height can be adjusted is matched with the bottom surface of the existing water channel, and the soil below the earth is retained.

  In cases other than the above, by closing the upper partition wall, it is possible to cope with a construction method in which the upper partition wall is also earthed as usual in the upper part of the lower partition wall.

  According to the tenth aspect of the present invention, since the detachable closing wall is disposed, when the construction area includes a geological location that is easily collapsed, the front portion is closed in front of the front portion during excavation. By installing a wall and holding the earth, and removing the closing wall from the front part only when moving the open shield machine forward, the state where the earth retaining in front of the front part is released is suppressed in a short time and the front of the open shield machine The construction method can prevent the collapse of the natural ground.

  In addition, when constructing a place that is self-supporting to the extent that the front front wall does not require a closing wall, the normal construction method is to keep the front part always open by removing the removable wall. It can correspond to.

  As described above, the open shield construction method and the open shield machine of the present invention can be used without changing a plurality of open shield machines for each construction method even if the construction method is changed during construction. Since it can correspond to each construction method, economical and efficient construction is possible.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal rear view showing a tail portion of a first embodiment of an open shield machine of the present invention, and FIG. 2 is an overall plan view. Since the basic configuration of the open shield method using the open shield machine of the present invention is the same as that of the conventional example, detailed description thereof is omitted here. Moreover, the same code | symbol is attached | subjected about the component same as the said prior art example.

  Similarly to the conventional example shown in FIG. 20, the open shield machine of the present invention is divided into a plurality of bodies in the front-rear direction, and the front end of the rear body (tail machine) 23 having the tail portion 1c is slightly reduced in cross-sectional area. Then, this is inserted into the rear end of the front machine body (front machine) 24 having the front portion 1d, and can be bent at the middle bent portion 1e as a mutual fitting portion.

  The tail machine 23 is provided with a tail partition wall 31 between the left and right side wall plates 25 at the front part and the rear end of the reduced cross-sectional area that fits into the rear end of the front machine 24. The rear jack is a tail portion 1c, and on the rear surface of the tail partition wall 31, the propulsion jacks 2 are arranged on both the left and right sides and in a plurality of upper and lower stages in accordance with the position of the side plate of the concrete box to be installed. ing.

  As shown in FIG. 3, the bottom plate portion 27 connected to the left and right side wall plates 25 in the middle bent portion 1 e and the tail portion 1 c in the portion in front of the rear end of the propelled jack 2 in the contracted state is also shown in FIG. 3. In the subsequent portion of the tail portion 1c, the bottom plate 20 made of a metal plate that does not communicate with the left and right side wall plates 25 and the bottom plate portion 27 is disposed, and the left and right edges of the left and right edges are left with the mounting plates 21a left and right. A bolt box 21 having an upper surface opening is formed at both ends, and a bolt box 17 having an inner surface opening is formed in correspondence with this by leaving the mounting plate 17a at the lower ends of the left and right side wall plates 25.

  In both bolt boxes 21, 17, both mounting plates 21 a, 17 a are fixed to each other with hexagon bolts 18 and nuts 15, and the bottom plate 20 is detachably mounted between the left and right side wall plates 25. A sealing material (not shown) made of water-swelling rubber is attached to one or both sides of the contact surfaces of the mounting plates 21a and 17a and the contact surface between the rear end of the bottom plate portion 27 and the tip of the bottom plate 20. deep.

  On the other hand, a front partition wall 32 is disposed between the left and right side wall plates 1a at the front end of the fitting portion at the front end of the tail machine 23 at the rear part of the front machine 24. A bottom plate 1b connected to the left and right side wall plates 1a is provided, and the end portions of the side wall plate 1a and the bottom plate 1b are formed as blade edges 11. Further, the front end and the upper surface of the front portion 1d are open surfaces, and the middle folding jacks 30 are arranged on the left and right sides of the front portion partition wall 32 in a rearward direction and in a plurality of upper and lower stages.

  Then, an earth pressure adjusting jack 28 having two upper and lower stages is provided on the left and right sides of the front surface of the front partition wall 32, and a partition wall 3 that divides the front portion 1d in the front and rear directions is attached to the front end thereof. It is slidably supported back and forth within the front portion 1d.

  Next, an embodiment of the open shield method of the present invention performed using the open shield machine 1 configured as described above will be described. The concrete box burying method and the concrete box to be used are the same as those in the conventional example.

  First, when constructing a place where the groundwater level is high or the ground is unstable, with the bottom plate 20 attached to the tail portion 1c, the open shield machine 1 is dug in the ground and the concrete box 4 is sequentially suspended. In the process of embedding the concrete boxes 4 in a vertical row, the concrete box 4 is suspended from the tail portion 1 c of the open shield machine 1 and placed on the bottom plate 20.

  Since the bottom plate 20 is secured by bolting and supported by the side wall plate 25 of the tail portion 1c in a stable manner, the load of the concrete box 4 placed on the bottom plate 20 can be firmly supported.

  When the concrete box 4 is suspended from the tail portion 1c, a height adjusting material such as a concrete block is disposed under the concrete box 4, and the left and right and lower portions of the concrete box 4 are placed in the tail portion 1c. As a primary injection into the gap, a grout material as a backfill material is filled.

  When the primary injection is completed, the excavator such as a backhoe excavates the front portion 1d and the front face mountain in front thereof. Thereafter, the propulsion jack 2 is extended, the reaction force is taken from the concrete box 4 in the tail portion 1c, and the open shield machine 1 is advanced. Thereby, the concrete box 4 moves relatively behind the open shield machine 1.

  At this time, since the bottom plate 20 is fixed to the left and right side wall plates 25 by bolting and the rearward movement is restricted, the bottom plate 20 together with the concrete box 4 and the tail part are moved along with the rearward movement of the concrete box 4. It does not fall out behind 1c. That is, the hexagon bolt 18 acts as a means for restricting movement of the bottom plate 20 to the rear at the joint between the bottom plate 20 and the side wall plate 25.

  In addition, since the space between the left and right side wall plates 1a and the bottom plate portion 27 and the bottom plate 20 is stopped by a sealing material, even in the case of constructing a place where the groundwater level is high, the inside of the tail portion 1c from around the bottom plate 20 Therefore, the groundwater does not enter the wall, and the installation of the concrete box 4 and the backfilling operation are not hindered.

  Moreover, when the partition 3 moves forward as the open shield machine 1 moves forward, the sediment in the front portion 1d and the front thereof is consolidated. However, if the surrounding natural ground is easily degraded, The earth pressure adjusting jack 28 is extended to push the partition wall 3 forward, thereby further compacting the sand in the front portion 1d and the front thereof, thereby facilitating excavation and soil removal with an excavator.

  In this way, when the ground is unstable or the groundwater level is high, for example, the geology is likely to collapse, by installing the bottom plate 20 to the tail portion 1c, the back-filling type construction is performed. Can do.

  On the other hand, when the construction of the surrounding natural ground is changed during the construction, and the construction where the groundwater level is low and the ground is stable is continued, the bottom plate 20 is removed from the tail portion 1c by the following procedure. First, the strut 34 and the press bar 8 are arranged between the concrete box 4 and the contracted jack 2 in the tail portion 1c, and the jack 2 is extended so that the concrete box 4 on the bottom plate 20 is attached to the tail section 1c. Push it backwards.

  Next, the strut 34 and the press bar 8 are removed, the bolts 18 and the nuts 15 are removed from the bolt boxes 21 and 17, and the bottom plate 20 is pulled up from the top and removed from the tail portion 1c.

  By removing the bottom plate 20 from the tail part 1c in this way, as shown in FIG. 5, there is no obstruction when the concrete box 4 is suspended in the tail part 1c, and the concrete box is placed on the excavated ground. 4 can be mounted directly. As a result, construction without backfilling can be performed.

  The thickness of the bottom plate 20 that has been removed is adjusted by burying excavated soil on the excavated ground or by spreading gravel or the like before the concrete box 4 is suspended from the tail portion 1c.

  On the other hand, when the construction site is switched from the location where the groundwater level is low and the ground is stable to the location where the ground is unstable or the groundwater level is high, the propulsion contracted with the concrete box 4 in the tail portion 1c as described above. The strut 34 and the press bar 8 are disposed between the jack 2 and the propulsion jack 2 is extended to push the concrete box 4 in the tail portion 1c to the rear of the tail portion 1c.

  Then, the strut 34 and the press bar 8 are removed, the bottom plate 20 is suspended from the tail portion 1c, and the bottom plate 20 is bolted to the lower ends of the left and right side wall plates 25 in the bolt boxes 21 and 17 as described above.

  In this way, it is possible to correspond to both the construction method of performing backfill injection and the construction method of not performing backfill injection only by attaching and detaching the bottom plate 20, and there are construction points by different construction methods within the construction range. Even in this case, it is possible to efficiently perform the construction without replacing the open shield machine 1 during the construction.

  In addition, when the width of the open shield machine 1 cannot be made very large with respect to the width of the concrete box 4 to be installed due to surrounding circumstances, the bottom plate 20 is directly attached to the lower ends of the left and right side wall plates 25 as described above. However, in other cases, as shown in FIG. 6, the protruding portion 16 may be formed by bending the lower end of the side wall plate 1a inward. The distance between the left and right projecting portions 16 is set to be longer than the width of the concrete box to be installed.

  In this case as well, as shown in FIG. 7, bolt boxes 21 having upper surface openings are formed on both left and right sides with the attachment plates 21a left on both left and right edges of the bottom plate 20 made of a metal plate. A bolt box 17 having an inner surface opening is formed leaving the mounting plate 17a at the lower ends of the left and right side wall plates 25.

  In the same manner as described above, the bottom plate 20 is bolted with the hexagon bolts 18 and the nuts 15 in the bolt boxes 21 and 17 with the sealing material stopped with a sealing material, so that the bottom plate 20 can be freely attached and detached between the left and right projecting portions 16. Install to.

  If the overhanging portion 16 is provided in this way, as shown in FIG. 8, when the open shield machine 1 is used with the bottom plate 20 removed, the ground contact area of the tail portion 1c to the ground is equivalent to the overhanging portion 16. And the sinking of the open shield machine 1 due to the weight of the open shield machine 1 can be reduced even on relatively soft ground.

  In any case, the bottom plate 20 is attached by bolting. However, the present invention is not limited to this, and there is a step that engages with the lower end of the side wall plate 25 or the tip of the overhanging portion 16 and the left and right side edges of the bottom plate 20. The bottom plate 20 may be attached by being provided.

  However, when the movement of the bottom plate 20 to the rear of the tail portion 1c is not restricted by the attachment means of the bottom plate 20, in order to restrict such movement, the movement regulating means such as a pin or a hook is used as the bottom plate 20 and the side wall plate. 25, or between the bottom plate 20 and the front portion of the tail portion 1c.

  If the bottom plate 20 is attached by bolting, the bottom plate 20 can be held between the left and right side wall plates 25 and can be easily attached and detached, and at the same time, movement of the bottom plate 20 to the rear of the tail portion 1c can be restricted. Therefore, it is preferable.

  Next, a second embodiment of the open shield machine of the present invention is shown in FIG. Since the configuration of the detachable bottom plate 20 of the tail portion 1c is the same as that of the first embodiment, description thereof is omitted.

  Similarly to the first embodiment, the open shield machine 1 according to the present embodiment can be bent by dividing the fuselage into front and rear, but the tail machine 23 is not provided with the tail partition plate 31, Protruding walls 52 are provided inwardly from the left and right side wall plates 25 at the rear end of the front portion and the reduced cross-sectional area that fits into the rear end of the front machine 24, and the front is a center folded portion 1e and the rear is a tail portion 1c. To do. Then, in accordance with the position of the side plate of the concrete box to be installed on the back surface of the projecting wall 52, the propulsion jacks 2 are arranged on the left and right sides and in a plurality of upper and lower stages in the rearward direction.

  Further, the front machine 24 is not provided with a front partition wall 32, and the left and right side wall plates 1a of the fitting part at the tip of the tail machine 23 are reduced from the inside at the rear part of the front machine 24, and the stepped part 33 formed thereby is rearward. The middle folding jacks 30 are arranged on the left and right sides and in a plurality of stages.

  A front part 1d is provided in front of the step part 33, and a bottom plate 1b connected to the left and right side wall plates 1a is provided on the bottom surface of the front machine 24, and the tips of the side wall plate 1a and the bottom plate 1b are formed as blade edges 11. The front end and the upper surface of the front portion 1d are open surfaces.

  Between the left and right side wall plates 1a slightly closer to the rear than the middle of the front portion 1d, an openable / closable partition wall 3 that divides the front portion 1d into the front and rear is disposed. The partition wall 3 is provided with a double door that opens rearward and is attached via a hinge.

  In addition, the opening / closing method of the partition wall 3 is not limited to the above-described rear-opening double door type, but is also a folding door type (FIG. 10), front open double door type (FIG. 11), and vertical slide type (FIG. 12). Various systems such as a shutter system (FIG. 13) and a forward tilt system (FIG. 14) can be employed.

  However, in the case of adopting a front-opening double-spread type, if the hinges are attached to both ends of the partition wall 3, when the partition wall 3 is opened, due to the presence of the side wall 42 of the existing water channel 40 taken into the front portion 1d, the partition wall 3 cannot be fully opened, it is preferable to set the lateral width of the opening / closing portion of the partition wall 3 to be equal to or smaller than the inner width of the existing water channel 40 (the width between the side walls 42).

  Then, the left and right gaps between the tail machine 23 and the front machine 24 are blocked by the water-stopping material 36 rich in flexibility, such as rubber, in the folded portion 1e.

  The usage and action will be described. When the existing water channel 40 exists within the construction range and the concrete box 4 is newly installed while removing the water channel, the water in the existing water channel 40 is repaired. In the state where the bottom plate 20 is attached to the tail portion 1c and the partition wall 3 is closed, the open shield machine 1 is made to face the existing water channel 40.

  Then, one section of the rear end of the existing water channel 40 is taken into the front portion 1d, and one section of the existing water channel 40 is removed with the periphery of the rear end of the existing water channel 40 secured by the side wall plate 1a. The concrete box 4 is suspended above 20, the earth and sand in front of the bulkhead 3 are excavated, and the back shield injection around the concrete box 4 and the propulsion of the open shield machine 1 by the extension of the propulsion jack 2 are repeated.

  Then, when the work of the day is over and the water blocked from the existing water channel 40 is discharged, or when it is necessary to drain the water that has flowed into the existing water channel due to heavy rain, etc., the rear of the existing water channel 40 The partition 3 is opened with the end taken into the front portion 1d.

  As a result, the open shield machine 1 becomes a bowl with a U-shaped cross section and can drain from the existing water channel 40 to the refurbished water channel by the concrete box 4 at the rear, avoiding the danger of water overflowing from inside the open shield machine 1 In addition, it is not necessary to secure a separate drainage route.

  Further, the tail plate 1c of the open shield machine 1 is in a state where the bottom plate 20 is mounted, and between the side wall plate 25 and the bottom plate portion 27 and the bottom plate 20, and between the fitting portion between the tail machine 23 and the front machine 24. Since the gap is stopped, water does not leak from the open shield machine 1 during discharge and scour the surrounding ground.

  On the other hand, when the construction of the surrounding ground changes in the middle of construction, and the construction where the groundwater level is low and the ground is stable is continued, the bottom plate 20 of the tail portion 1c is formed as in the first embodiment. The concrete box 4 is pushed backward, the bolting is released, the bottom plate 20 is removed, and the bottom plate 20 is removed from the tail portion 1c so that the suspended concrete box 4 is directly on the excavated ground. Mounted by a construction method that does not perform backfill injection.

  Next, FIG. 15 and FIG. 16 show a third embodiment of the open shield machine of the present invention. The basic configuration of this embodiment is the same as that of the first embodiment, but differs from the first embodiment in that the partition wall 3 is divided into two upper and lower stages.

  The lower partition wall 37 is formed with a door pocket 39 vertically downward from the upper surface of the bottom plate 1b of the front portion 1d corresponding to the position of the lower partition wall 37, and vertical sliding grooves (illustrated) are formed inside the left and right side wall plates 1a. The lower end of the lower partition wall 37 is stored in the door pocket 39 and is slidable up and down.

  Further, the slide range of the lower partition 37 is set to a height range that the bottom surface of the existing water channel 40 can take with respect to the open shield machine 1, and the height of the lower partition wall 37 is set to the height of the bottom surface of the existing water channel 40. So that it can be adjusted according to the

  On the other hand, the upper partition 38 is of an open / close type, and various types of open / close methods can be adopted as in the second embodiment. In the case of adopting a method capable of adjusting the height of the lower end, the lower end of the upper partition 38 is set to be lowered to the same height as the upper end of the lower partition 37 in the lowest state.

  Further, when adopting a method in which the lower end height cannot be adjusted, the lower end position is set to the same height as the upper end of the lower partition wall 37 in the lowest position, and before and after the lower partition wall 37. Regarding the positional relationship, the upper partition wall 38 is disposed in the same direction as the opening / closing direction with respect to the lower partition wall 37.

  The usage and operation of the open shield machine 1 will be described. There is an existing water channel 40 within the construction range, and a new concrete box 4 is installed while removing this, so that the water channel can be repaired, and the bottom of the open shield machine 1 and the existing water channel 40 When there is a difference in height from the bottom, first, as in the second embodiment, the water in the existing water channel 40 is blocked upstream from the construction site, and then the bottom plate 20 is attached to the tail portion 1c to form the upper partition wall 38. In the closed state, the open shield machine 1 is opposed to the existing water channel 40, and the backfill injection type construction is performed while removing the existing water channel 40. Since each process is the same as that of the second embodiment, a detailed description thereof is omitted here.

  Then, when the work of the day is over and the water blocked from the existing water channel 40 is discharged, or when it is necessary to drain the water that has flowed into the existing water channel due to heavy rain, etc., the rear of the existing water channel 40 With the end taken into the front portion 1d, the lower partition 37 is slid up and down to match the height of the bottom surface of the existing water channel 40, and the upper partition 38 is opened.

  The positioning and fixing when the lower partition wall 37 is slid up and down is performed by bolting the lower partition wall 37 to the side wall plate 25 as appropriate.

  Thereby, the open shield machine 1 becomes a trough having a U-shaped cross section, and can be drained from the existing water channel 40 to the repaired water channel by the rear concrete box 4.

  Moreover, even if the sediment below the bottom surface of the existing water channel 40 remains in the front part 1d, it is retained by the lower partition wall 37, so that the soil in the front part 1d is swept backward together with the water. It does not obstruct the installation work of the concrete box 4 that accumulates in the tail portion 1d, and does not collect in the existing water channel that has been repaired and narrow the internal space of the water channel.

  In this way, by setting the partition wall 3 in two upper and lower stages, even when there is a height difference between the bottom surface of the open shield machine 1 and the bottom surface of the existing water channel 40, the soil with the difference in height is made to be soiled by the partition wall 37 in the lower stage. The upper partition wall 38 can be opened and water from the existing water channel 40 can be sent backward through the open shield machine 1 while being fastened.

  Moreover, it is possible to discharge even during renovation work of the waterway, and it is not necessary to secure a separate drainage route, and a large amount of water does not leak from the open shield machine 1 during discharge and the surrounding ground is not scoured. The points are the same as in the second embodiment.

  The height of the lower partition wall 37 can be adjusted easily by making it vertically slidable. However, the height adjustment method is not limited to this. For example, the lower partition wall 37 is further divided into a plurality of upper and lower parts. It is also possible to adjust according to the number of plates to be arranged.

  On the other hand, when the construction of the surrounding ground changes during the construction, and the construction where the groundwater level is low and the ground is stable is continued, the bottom plate 20 is removed from the tail portion 1c to perform the construction without backfill injection. The points to be performed are the same as in the first embodiment.

  Next, a fourth embodiment of the open shield machine of the present invention will be described. As shown in FIG. 17, the open shield machine 1 of the present embodiment is also capable of bending by dividing the fuselage into the front and rear, and the configuration of the rear part from the middle folding part 1 e is the same as that of the first embodiment. Therefore, detailed description here is omitted.

  The open shield machine 1 of the present embodiment includes a partition wall 3 between the left and right side wall plates 1a at the rear part of the front machine 24, and covers the front of the front part 1d including the partition wall 3 as a front part 1d. In this manner, the closing wall 13 made of a metal plate is disposed in the width direction, and both ends thereof are bent backward so as to cover the ends of the left and right side wall plates 1a from the outside.

  In addition, you may provide the guide groove which mutually fits in the inner side of the bending part of the both ends of the closing wall 13, and the side wall board 1a front end outer side of the front part 1d. Thereby, the closing wall 13 can be slid up and down on the front portion 1d to be detachable, and the closing wall 13 can be prevented from being tilted forward of the front portion 1d with the closing wall 13 disposed.

  Next, an embodiment of the open shield method of the present invention using the open shield machine 1 configured as described above will be described. The concrete box burying method and the concrete box to be used are the same as those in the conventional example.

  First, when constructing a place where the ground is likely to collapse, the closing wall 13 is disposed in front of the front portion 1d as shown in FIG. 17 as a first step with the bottom plate 20 attached to the tail portion 1c.

  In this state, the earth and sand in the front portion 1d is excavated and discharged by an excavator such as a backhoe. At this time, since the front part of the front part 1d is covered with the closing wall 13, the ground in front of the open shield machine 1 collapses while excavating the inside of the front part 1d and flows into the front part 1d. The mountain never gets loose.

  Further, the earth retaining by the closing wall 13 allows the front portion 1d to be excavated and discharged to be emptied while preventing the collapsed earth and sand from flowing into the front portion 1d from the front.

  When the interior of the front portion 1d becomes empty, as a second step, the closing wall 13 is removed from the front portion 1d, the front portion 1d is opened, the propulsion jack 2 is immediately extended, and the concrete box 4 at the rear is reacted. As a result, the open shield machine 1 is moved forward.

  At this time, since the interior of the front part 1d is emptied in the previous excavation and soil removal process, the thrust of the open shield machine 1 increases due to earth pressure accumulated in the front part 1d, and the open shield machine It becomes possible to prevent the propulsion 1 from becoming difficult or being damaged by applying an excessive load to the concrete box 4 that transmits the propulsion reaction force.

  When the forward movement is finished, as a third step, the closing wall 13 is immediately arranged in front of the front portion 1d, the propulsion jack 2 is contracted in that state, the concrete box 4 is suspended from the tail portion 1c, and the bottom plate 20 Backfill injection (primary injection) is performed above, and the process returns to the first step.

  In this way, the front of the front portion 1d is continuously covered with the closing wall 13 until immediately before the open shield machine 1 is moved forward, so that the time during which the front of the front portion 1d is open is short, and the collapse of the surrounding natural ground advances during that time. There is no end.

  On the other hand, when the construction of the surrounding natural ground changes in the middle of construction and the construction where the ground is difficult to collapse is continued, the construction is performed with the front wall 1d opened without using the closing wall 13. In addition, the point which removes the baseplate 20 in the tail part 1c and performs construction without backfilling injection | pouring is the same as that of the said 1st Example.

  Thus, each construction method in the case where the place where the ground is easy to collapse and the place where the ground is not collapsed is mixed in the construction range is the attachment / detachment of the bottom plate 20 at the tail portion 1c and the arrangement / disposition of the closing wall 13 in front of the front portion 1d. Since it is realizable only by removal, even if it prepares separately the open shield machine 1 for every construction method and does not replace this in the middle of construction, it can be made to correspond to the construction method suitable for each construction location.

  The closing wall 13 is not only disposed so as to cover the front portion 1d, but also detachably disposed at the front position between the left and right side wall plates 1a in the front portion 1d. Further, as shown in FIG. 18, it may be divided into a plurality of right and left parts and detachable by sliding up and down as a guide using an H-section steel 29 standing on the top surface of the front part of the bottom plate 1b.

  However, in order to ensure the maximum enclosed space in the front portion 1d by the closing wall 13 and the left and right side wall plates 1a, the closing wall 13 is disposed so as to cover the front end of the front portion 1d as in the above-described embodiment. Is preferred.

  As described above, the open shield method according to the present embodiment is performed using the open shield machine 1 including the closed wall 13 that is detachable with respect to the front portion 1d. However, the present invention is not limited thereto, and the open wall is not provided. An existing open shield machine can be used in combination with the closed wall 13 separately.

  Further, the present invention can be applied not only to a bendable open shield machine in which the airframe is divided into a plurality of front and rear parts, but also to an entire open shield machine as shown in FIG.

It is a vertical rear view which shows the tail part of 1st Embodiment of the open shield machine of this invention. It is a whole top view showing a 1st embodiment of an open shield machine of the present invention. It is a vertical rear view which shows the attachment part of a baseplate and a side wall board lower end. It is a vertical side view which shows 1st Embodiment of the open shield machine of this invention. It is a vertical rear view which shows the tail part of the state which removed the bottom plate. It is a vertical rear view which shows the Example of the tail part which provided the inward protrusion part in the side wall board lower end. It is a vertical rear view which shows the attachment part of a baseplate and an overhang | projection part. It is a vertical rear view which shows the tail part of the state which removed the bottom plate about the open shield machine of FIG. It is a whole top view which shows 2nd Embodiment of the open shield machine of this invention. It is a top view which shows the 2nd example of an opening-and-closing type partition. It is a top view which shows the 3rd example of an open / close type partition. It is a top view which shows the 4th example of an opening-and-closing type partition. It is a top view which shows the 5th example of an opening-and-closing type partition. It is a top view which shows the 6th example of an opening-and-closing type partition. It is a whole top view which shows 3rd Embodiment of the open shield machine of this invention. It is a vertical side view which shows 3rd Embodiment of the open shield machine of this invention. It is a top view which shows the front part of 4th Embodiment of the open shield machine of this invention. It is a top view which shows the other example of a closing wall. It is a vertical side view which shows the outline of an open shield construction method. It is a vertical side view of the open shield machine which divided the conventional airframe forward and backward. It is a perspective view of the conventional concrete box.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Open shield machine 1a Side wall board 1b Bottom board 1c Tail part 1d Front part 1e Folding part 2 Propulsion jack 3 Bulkhead 4 Concrete box 4a Left side board 4b Right side board 4c Upper floor board 4d Lower floor board 5 Backfill soil 6 Grout material 7 Height Adjusting material 8 Press bar 9 Excavator 10 Opening 11 Blade edge 13 Closing wall 15 Nut 16 Overhanging part 17 Bolt box 17a Mounting plate 18 Hexagon bolt 20 Bottom plate 21 Bolt box 21a Mounting plate 23 Tail machine 24 Front machine 25 Side wall plate 27 Bottom plate 28 Earth pressure adjusting jack 29 H-shaped steel 30 Folding jack 31 Tail part partition wall 32 Front part partition wall 33 Step part 34 Strut part 36 Water stop material 37 Lower partition wall 38 Upper partition wall 39 Door pocket 40 Existing water channel 41 Bottom floor plate 42 Side wall 50 Movable split edge 51 Rear Earth retaining plate 52 Protruding wall

Claims (10)

  Propulsion jacks are installed in the shield machine with the front and rear ends and the upper surface made up of the left and right side wall plates and the bottom plate connected to these side wall plates. A process, a process of extending the propulsion jack and advancing the shield machine with the reaction of the existing underground structure such as a concrete box that follows, and a new underground structure behind the propulsion jack contracted in the tail part of the shield machine In the open shield method of burying underground structures in series by repeating the process of setting things as appropriate, in the construction site that requires backfill injection around the underground structure, with the bottom plate attached to the tail part, Backfill injection is performed around the underground structure placed on the bottom plate, and at the construction site where backfill injection is not required, the bottom plate is removed and the excavated ground is Open shield method, wherein the backfilling of earth and sand therearound the underground construction directly mounted to.   Propulsion jacks are installed in the shield machine with the front and rear ends and the upper surface made up of the left and right side wall plates and the bottom plate connected to these side wall plates. A process, a process of extending the propulsion jack and advancing the shield machine with the reaction of the existing underground structure such as a concrete box that follows, and a new underground structure behind the propulsion jack contracted in the tail part of the shield machine In the open shield method where the underground structure is buried in series one after another by repeating the process of setting the object as appropriate, the underground structure on the excavated ground with the bottom plate removed from the tail at the construction site where the ground is difficult to collapse In the construction area where the ground is likely to collapse, the bottom plate is attached to the tail part and the front part of the shield machine With the closed wall covered, the underground structure is suspended on the bottom plate and backfilling is performed around the underground structure, and the enclosed space and the front portion are excavated and earthed. An open shield method characterized by repeating a process and a process of removing the closed wall and advancing the shield machine.   In the open shield machine with the front and rear ends and the upper surface consisting of the left and right side wall plates and the bottom plate connected to these side wall plates open, with the propeller jacks arranged vertically on the left and right in the rear tail part, The bottom plate is detachably disposed, and the bottom plate is attached so that the underground structure can be placed on the bottom plate of the tail portion, and the bottom plate is detached so that the underground structure can be placed directly on the excavated ground. Is an open shield machine that can be selected and used.   The open shield machine according to claim 3, wherein the left and right side edges of the bottom plate are detachably joined at the lower ends of the left and right side wall plates of the tail portion.   4. The open shield machine according to claim 3, wherein an inwardly projecting portion is provided at the lower ends of the left and right side wall plates of the tail portion, and the left and right side edges of the bottom plate are detachably joined at the tip of the projecting portion.   6. The open shield according to claim 4 or 5, wherein movement restricting means for restricting movement of the bottom plate to the rear of the tail portion is provided between a joint portion of the bottom plate and the side wall plate or between the bottom plate and the tail portion front portion. Machine.   The open shield machine according to any one of claims 3 to 6, wherein a partition wall disposed between the left and right side wall plates and slidable forward and backward is provided to divide the machine body in the front and rear direction.   The open shield machine according to any one of claims 3 to 6, wherein a partition wall disposed between the left and right side wall plates and configured to divide the inside of the machine forward and backward is freely openable and closable.   The partition between the left and right side wall plates that divides the airframe forward and backward is configured in two levels, the upper partition can be opened and closed, and the lower partition can be adjusted to the bottom of the existing waterway. The open shield machine according to any one of claims 3 to 6.   The open shield machine according to any one of claims 3 to 9, wherein a closed wall in the width direction of the open shield machine is detachably disposed in front of the front portion.

Images