JP4402640B2 - Open shield method - Google Patents

Description

  The present invention relates to an open shield method for constructing an underground structure such as an underground passage such as a water and sewage system, a common ditch, a telegraph / telephone, etc. in an urban area.

  The open shield method is a rational method that utilizes the advantages of the open cut method (open cut method) and the shield method, and the outline of the open shield machine 1 used in this open shield method is as shown in FIG. The front, rear, and top surfaces of the plate 1a and the bottom plate 1b connected to the side wall plates 1a are opened, the front ends of the side wall plate 1a and the bottom plate 1b are formed as blade edges 11, and the center of the side wall plate 1a Alternatively, the shield jacks 2 are arranged side by side in the vertical direction near the rear end. In the figure, 3 indicates a partition wall.

  The open shield method to be constructed using the open shield machine 1 is not shown in the figure, but the open shield machine 1 is installed in the start pit, the shield jack 2 of the open shield machine 1 is extended, and the inside of the start mine is The open shield machine 1 is advanced by taking the reaction force against the reaction wall, the first concrete box 4 forming the underground structure is suspended from above, and the shield is shrunk in the tail part 1c of the open shield machine 1 Set behind jack 2. A strut is disposed between the shield 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 top surface of open shield machine 1. Simultaneously with or after this earth removal step, the shield 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 part 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 as the open shield machine 1 moves forward. 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.

  The concrete box 4 is made of reinforced concrete and comprises a left side plate 4a, a right side plate 4b, an upper floor plate 4c, and a lower floor plate 4d as shown in FIG.

  In such an open shield method, as described above, excavation and earth removal are performed by an excavator 9 such as an excavator installed on the ground, and the concrete box 4 is set on the tail portion 1c of the open shield machine 1 on the ground. It will be carried out with a lifting machine such as an installed crawler crane.

  Therefore, when crossing directly under structures such as bridge girders and large pipes, the excavator and the lifting machine cannot be arranged in these places, and the construction of the open shield method becomes impossible.

  Therefore, as described above, there are obstacles such as bridge girders above the construction site, and even when crossing under them, the open shield machine used for the open shield method is installed as it is without being affected by this obstacle The following construction methods are available for construction of underground structures that can be used to construct underground structures and immediately move to the open shield construction method after passing obstacles and continue construction.

  As shown in FIG. 8, when the main push jack 13 is installed in the start shaft 14, and when crossing the lower part of the obstacle, the front shield of the open shield machine 1 is excavated and earthed, and the open shield machine 1 and the concrete box are combined. 4 is pushed out by the main push jack 13 installed in the start shaft 14, and a new concrete box 4 is arranged between the main push jack 13 and the pushed concrete box 4, and a propulsion process is repeated to repeat the push. It is incorporated in the shield method.

  And in the open shield method including such a propulsion process, the entire concrete box 4 with the backfill 5 on the upper surface is pushed out by the main push jack 13, so that the concrete box 4 moves forward. The backfill 5 may also move. Such movement of backfilling soils hinders the opening of traffic on the upper part of the installed box after backfilling.

  Therefore, as a means for solving such inconvenience, a friction cut plate 12 is disposed between the concrete box 4 and the backfill 5 as shown in FIG. The edge is cut. This friction cut plate is made of, for example, a steel plate having a thickness of about 6 to 9 mm and a width substantially equal to the width of the concrete box 4. Then, it is sequentially coupled to the friction cut plate 12 already installed on the upper surface of the concrete box 4.

  As a joining method, for example, there is welding as in the box-type roof method.

  The prior art is generally performed by those skilled in the art, and is not related to a known invention.

  As described above, the friction cut plate 12 is sequentially added from the start shaft 14 as the concrete box 4 is propelled. The friction cut plate 12 is fixed by the fixing member 15 only on the start shaft 14 side. Then, after the friction cut plate 12 is installed and fixed, only the concrete box 4 is advanced so as to slide under the friction cut plate 12.

  Conventionally, the friction cut plate 12 is laid over the entire upper surface of the concrete box 4. For this reason, if the extension of the laid concrete box 4 becomes long or the soil covering (the weight of the backfill soil) is large, the friction resistance between the concrete box 4 and the friction cut plate 12 increases, and the friction cut plate The deformation of the upper backfill 5 is caused, the friction cut plate 12 is broken, or the fixing member 15 of the friction cut plate 12 of the start shaft 14 is deformed. The start shaft 14 will be deformed.

  The object of the present invention is to solve the above-mentioned inconvenience, when a friction cut plate is laid on the top of the concrete box and the concrete box is propelled by cutting the edge with the backfill soil and propelling the concrete box. Laying on the top of the concrete box according to different conditions such as friction resistance with the cut plate, extension of the laid concrete box, and the weight of the backfill soil above the concrete box (soil covering) An object of the present invention is to provide an open shield method for appropriately setting the laying range of the friction cut plate.

In order to achieve the above object, the invention according to claim 1 includes a step of excavating and discharging soil in front of an open shield machine or a front opening of the open shield machine, and extending a propulsion jack to depress the concrete box. The process of advancing the shield machine with force and the process of hanging and setting a new concrete box from the upper side behind the propulsion jack shrunk in the tail part of the open shield machine are repeated as appropriate, and the concrete boxes are arranged in series. In this method, the front of the open shield machine is excavated and evacuated, and the open shield machine is pushed out with a push jack, and between the push jack and the extruded concrete box. Combined with the process of repeating the extrusion by arranging a new concrete box in the above, the process of propelling the concrete box In the open shield method to dispose the friction cutting plate on the upper surface of the concrete a box body, the friction cutting plate, so that frictional resistance between the friction cutting plate and concrete box-body decreases, connect the front and rear friction cutting plate bolt Thus, the gist is to connect the bolt heads so as to come out below the overlapped friction cut plates and arrange them in a stripe shape facing the propulsion direction of the concrete box .

  According to the first aspect of the present invention, the friction cut plate is not laid over the entire upper surface of the concrete box, but is provided with a gap, so that the frictional resistance between the concrete box and the friction cut plate is small. As a result, even if the length of the laid concrete box is long or the weight of the backfill soil on the top of the concrete box is large (soil covering), deformation due to elongation of the friction cut plate occurs. This prevents the movement of the backfill of the upper part, the fracture of the friction cut plate, or the deformation of the friction cut plate fixing member of the start shaft due to this, and also prevents the start shaft from being deformed.

  Since the frictional resistance between the friction cut plate and the concrete box can be reduced, the concrete box can be smoothly promoted.

  In addition, the amount of friction cut plate can be reduced, and not only the workability is improved, but also the cost can be reduced economically.

Furthermore, since the portion where the friction cut plate does not exist can be formed from the beginning to the end of the concrete box propulsion direction, the frictional resistance is reduced accordingly, and the concrete box advances smoothly.

The present invention according to claim 2 includes a step of excavating and discharging the earth and sand ahead of the front or upper surface opening of the open shield machine, and a step of extending the propulsion jack and advancing the shield machine using the concrete box as a reaction force. And the process of hanging and setting a new concrete box from the upper side behind the propulsion jack shrunk in the tail part of the open shield machine as necessary, and burying the concrete boxes in tandem one after another For excavating and excavating the front of the open shield machine, the open shield machine is pushed out with a push-out jack, and a new concrete box is placed between the push-out jack and the extruded concrete box. Combined with a propulsion process that repeats extrusion. In the open shield method to dispose the Deployment cut plate, the friction cutting plate, so that frictional resistance between the friction cutting plate and concrete box-body becomes smaller, the connection bolt before and after friction cutting plate, the bolt head The gist is to connect them so as to come out under the overlapped friction cut plates and arrange them in a checkered pattern .

  According to the second aspect of the present invention, since the friction cut plates are disposed in a scattered manner, the frictional resistance between the friction cut plates and the concrete box as a whole is reduced. Moreover, since the entire portion is reduced uniformly, the concrete box advances smoothly.

  As described above, the open shield method according to the present invention is a method in which a friction cut plate is laid on the top of a concrete box and the edge of the backfill soil is cut to propel the concrete box. Laying on the top of the concrete box according to different conditions such as friction resistance with the cut plate, extension of the laid concrete box, and the weight of the backfill soil above the concrete box (soil covering) Because the friction cutting plate can be set in an appropriate range, the frictional resistance between the friction cutting plate and the concrete box is reduced, and even if the weight of the backfill soil (soil cover) is large, the friction is reduced. This prevents the occurrence of deformation due to the extension of the cut plate. Breaking bets plate, or variations such as to prevent the friction-cut plate of the fixing member of the starting pit, prevent deformation of the starting pit.

  In addition, the concrete box can be smoothly promoted to improve the workability, and the amount of the friction cut plate can be reduced, so that the cost can be reduced economically.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view showing a first embodiment of an arrangement example of a friction cut plate used in the open shield method of the present invention, FIG. 2 is a vertical side view of the same, and FIG. 3 is a side view of a connection portion of the friction cut plate. Since the open shield method of the present invention is basically the same as the conventional example, a detailed description thereof is omitted here.

  Even in the method of the present invention, there is an obstacle such as a bridge girder above the construction site as described above, and even when crossing under the obstacle, the open shield machine used in the open shield method is installed as it is and is affected by this obstacle. The underground structure will be constructed without any obstacles, and after passing obstacles, the construction will be continued immediately by moving to the open shield method.

  And when an obstacle exists and crosses the lower part, as shown in FIG. 7, the pushing jack 13 is installed in the start shaft 14, and the front of the open shield machine 1 is excavated and earthed. The concrete box 4 is pushed out by the main pushing jack 13 installed in the start shaft 14, and a new concrete box 4 is arranged between the main pushing jack 13 and the pushed concrete box 4, and the pushing is repeated. Incorporate the process into the open shield method. In the figure, 16 indicates a bearing wall.

  In the propulsion step, a friction cut plate 12 is disposed between the backfill 5 at the top of the concrete box 4 and the concrete box 4 to cut the edge between the concrete box 4 and the backfill 5. The backfill soil 5 is prevented from moving with the propulsion of the concrete box 4.

  In this case, in the present invention, the friction cut plate 12 is not disposed over the entire upper surface of the concrete box 4, but the friction resistance between the concrete box 4 and the friction cut plate 12, and the installed concrete box 4 The laying arrangement of the friction cut plate 12 to be laid on the top of the concrete box 4 is appropriately set according to different conditions such as extension and the weight of the backfill soil 5 on the top of the concrete box 4 (soil covering). .

  FIG. 1 to FIG. 3 show a first embodiment showing the laying arrangement of the friction cut plate 12, which is arranged in a stripe shape extending in the same direction toward the propulsion direction of the open shield machine 1, and left and right with respect to the propulsion direction. An interval 19 was provided. In the figure, reference numeral 18 denotes a connection bolt for connecting the front and rear friction cut plates 12, and the bolt heads protrude below the overlapped friction cut plates 12.

  In the example shown in FIG. 1, the width of the friction cut plate 12 is set to one fifth of the width of the concrete box 4, and the friction cut plates 12 are arranged in three rows a, b, and c at intervals A and B. Arranged.

  And even if it will be set as a + b + c> A + B and the part which the concrete box 4 and the backfill soil 5 will contact directly by setting the space | interval 19 will be the concrete box 4 and the backfill soil 5 Since the area in which the concrete box 4 is in direct contact is smaller than the area in which the concrete box 4 and the friction cut plate 12 are in contact with each other, the edge of the concrete box 4 and the backfill soil 5 is cut by the friction cut plate 12. The intended purpose of disposing 12 can be achieved.

  Therefore, when the concrete box 4 is propelled by the push jack 13 together with the open shield machine 1 below the friction cut plate 12, the concrete box 4 is cut from the backfill soil 5 by the friction cut plate 12. However, since the entire surface of the concrete box 4 is not in contact with the friction cut plate 12 but only in part, the frictional resistance during propulsion is reduced. The As a result, it is possible to prevent the deformation due to the extension of the friction cut plate 12.

  And since the space | interval 19 in which the friction cut plate 12 is not arrange | positioned is the same direction as the propulsion direction of the concrete box 4, the concrete box 4 can be smoothly pushed.

  4 to 6 show a second embodiment of the laying arrangement of the friction cut plate 12. The friction cut plate 12 has a horizontal width similar to that of the first embodiment, for example, and has a square shape as a whole whose length is substantially equal to the horizontal width. Formed.

  This square-shaped friction cut plate 12 is arranged in a checkered pattern, and the friction cut plate 12 positioned laterally at a distance from the propulsion direction of the concrete box 4 is connected to a connecting steel material 17 such as L-shaped steel. It connects with the bolt 18.

  Thereby, the space | interval 19 which is a space | gap with the adjacent friction cut plate 12 is also formed in a checkered pattern shape, and it arrange | positions in the state which the friction cut plate 12 is scattered in the upper part of the concrete box 4 whole.

  Therefore, in the process of propelling the concrete box 4 with the main push jack 13, the concrete box 4 is propelled in a state where the edge of the concrete box 4 is cut off from the backfill 5 by the friction cut plate 12. However, since the entire surface of the concrete box 4 is not in contact with the friction cut plate 12 but only in partial contact, the frictional resistance during propulsion is reduced. As a result, it is possible to prevent the deformation due to the extension of the friction cut plate 12.

It is a top view which shows 1st Embodiment of the example of arrangement | positioning of the friction cut plate in the open shield method of this invention. It is a vertical side view of 1st Embodiment of the arrangement example of the friction cut plate in the open shield method of this invention. It is a side view of the connection part which shows 1st Embodiment of the arrangement example of the friction cut plate in the open shield method of this invention. It is a top view which shows 2nd Embodiment of the example of arrangement | positioning of the friction cut plate in the open shield method of this invention. It is a vertical side view of 2nd Embodiment of the arrangement example of the friction cut plate in the open shield method of this invention. It is a side view of the connection part which shows 2nd Embodiment of the arrangement example of the friction cut plate in the open shield method of this invention. It is explanatory drawing of the open shield construction method of this invention. It is explanatory drawing of the conventional open shield construction method. It is a vertical side view which shows the outline of an open shield construction method. It is a perspective view of a concrete box.

DESCRIPTION OF SYMBOLS 1 Open shield machine 1a Side wall plate 1b Bottom plate 1c Tail part 1d Front part 2 Shield 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 adjustment material 8 Press Bar 9 Excavator 10 Opening
DESCRIPTION OF SYMBOLS 11 Cutting edge 12 Friction cut plate 13 Main jack 14 Starting shaft 15 Fixing member 16 Bearing wall 17 Steel for connection 18 Connection bolt 19 Spacing

Claims (2)

In the process of excavating and discharging soil in front of the front or top opening of the open shield machine, extending the propulsion jack and advancing the shield machine with the concrete box as a reaction force, and in the tail part of the open shield machine Open shield is a method of burying concrete boxes in tandem and backfilling the upper part of the concrete box by repeating the process of hanging a new concrete box from above and setting it behind the shortened propulsion jack. Combined with a propulsion process that excavates and discharges the front of the machine, pushes the open shield machine together with a push-out jack, places a new concrete box between the push-out jack and the extruded concrete box, and repeats the push. In the process of propelling the concrete box, a friction cut plate is placed on the top surface of the concrete box. In the open shield method to set, the friction cutting plate, so that frictional resistance between the friction cutting plate and concrete box-body becomes smaller, the connection bolt before and after friction cutting plate, friction cuts bolt head is superimposed An open shield construction method, characterized in that it is connected in such a way as to come out under the plate and is arranged in a stripe shape facing the propulsion direction of the concrete box . In the process of excavating and discharging the soil in front of the front or top opening of the open shield machine, in the process of extending the propulsion jack and advancing the shield machine with the concrete box as a reaction force, and in the tail part of the open shield machine Open shield is a method of burying concrete boxes in tandem and backfilling the upper part of the concrete box by repeating the process of hanging a new concrete box from above and setting it behind the shortened propulsion jack. Combined with the propulsion process of excavating and discharging the front of the machine, extruding the open shield machine with the main jack, placing a new concrete box between the main jack and the extruded concrete box, and repeating the extrusion. In the process of propelling the concrete box, a friction cut plate is placed on the top surface of the concrete box. In the open shield method to set, the friction cutting plate, so that frictional resistance between the friction cutting plate and concrete box-body becomes smaller, the connection bolt before and after friction cutting plate, friction cuts bolt head is superimposed An open shield construction method, characterized by connecting it so that it comes out under the plate and arranging it in a checkered pattern .

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