JP5466140B2 - Open shield method and open shield machine - Google Patents

Description

  The present invention relates to an open shield method and an open shield machine for constructing underground structures such as water and sewage systems and underground passages in an urban area.

  The open shield method is an efficient method that takes advantage of the open cut method (open cut method) and the shield method. Of these open shield methods, the body of the open shield machine 1 is divided into multiple parts in the longitudinal direction. The self-propelled open shield machine 1 that takes the reaction force from other divided blocks and moves forward in the same way as the ESA method (ENDLESS SELF ADVANCING METHOD) "Infinite self-propelled forward construction method" is the following patent Proposed as shown in the literature.

The ESA method (ENDLESS SELF ADVANCING METHOD) “infinite self-propelled forward method” is similar in principle to the movement of the worm, and the head is advanced with the tail fixed (reaction force). Next, the head is fixed (reaction force) and the tail moves. This is repeated to advance, and a plurality of (three or more) box culverts are connected with PC steel wires, and hydraulic jacks are installed between and at the end of each box culvert to constitute an ESA facility. The jack pressure is transmitted to each box culvert. When one box culvert is propelled, the friction resistance force due to the earth pressure and its own weight of the other plurality of box culverts is used as a reaction force resistor, and the box culvert is sequentially propelled one by one.
JP 2000-64779 A JP 2002-349187 A

  As shown in FIGS. 26, 27, and 28, the open shield machine 1 divides the machine body into a plurality of parts in the front-rear direction, and in this embodiment, a front part 1 d having a blade edge 11 at the tip, a jack part 1e and the tail part 1c on which the concrete box 4 is suspended. The first propulsion / traction jack 12 is placed between the front part 1d and the jack part 1e, and the jack part 1e and the tail part 1c are connected. A second propulsion / traction jack 13 is disposed between them, and a third propulsion / traction jack 14 is disposed between the front portion 1d and the tail portion 1c. Pin jacks are used for these propulsion / traction jacks 12, 13, and 14.

  In the example of Patent Document 2, the width of the body of the front part 1d, the jack part 1e, and the tail part 1c is such that the jack part 1e is smaller than the front part 1d and the tail part 1c is smaller than the jack part 1e. It is formed so that it gradually decreases as it goes backward with respect to the propulsion direction.

  A steel friction cutter 15 divided into a plurality of parts is provided at the bottom of the front part 1d, and a friction cutter jack 19 for advancing the friction cutter 15 is provided at the bottom of the front part 1d.

  An outkey jack (slit) 16 is provided on the side of the jack portion 1e so that the outkey (slit) 16 extends over the side ground and penetrates into the ground, and a reaction force is obtained from the ground.

  Further, a stopper jack 18 for obtaining a reaction force from the rear concrete box 4 is disposed at the rear portion of the jack portion 1e.

  In the open shield method using such an open shield machine 1, the forward shield method of the open shield machine 1 first lays the concrete box 4 in the tail portion 1c as the first step.

  Next, as a second step, the friction cutter jack 19 disposed at the bottom of the front portion 1d is extended to advance the friction cutter 15.

  Thereafter, as the third step, the first propulsion / traction jack 12 is extended, and only the front portion 1 d is advanced by the stroke of the first propulsion / traction jack 12. At this time, the first propulsion / traction jack 12 extends with the reaction force of frictional resistance caused by the weight of the rear jack portion 1e and tail portion 1c and earth pressure.

  In this case, since the front portion 1d moves forward on the friction cutter 15 advanced in the previous step, both of them become sliding friction between the steel friction cutter 15 and the bottom portion of the front portion 1d, and the front portion 1d is used for excavation. The frictional resistance is small, and the front portion 1d can move forward in a sliding manner. When the front portion 1d is dug, the friction cutter jack 19 is set in a relief state and returned at the same speed as the propulsion speed of the front portion 1d.

  In addition, when the front part 1d moves forward, frictional resistance is also generated between the front part 1d and the ground, and if the reaction force is insufficient, the outkey jack 17 disposed on the jack part 1e is extended. The outkey (slit) 16 projects over the side ground and penetrates into the ground. Thereby, the jack part 1e is fixed to the natural ground, and the reaction force can be increased.

  If the reaction force is still insufficient with the outkey (slit) 16, the stopper jack 18 is extended rearward and the tip is brought into contact with the concrete box 4, so that the jack portion 1e and the tail when the front portion 1d moves forward. The part 1c is prevented from returning to the rear, and a deficient reaction force is obtained from the concrete box 4. In this case, the stopper jack 18 is for obtaining the reaction force that is insufficient as described above from the concrete box 4 and is not propelled by the stopper jack 18.

  Next, as the fourth step, the second propulsion / traction jack 13 is extended to advance the jack portion 1e toward the front portion 1d.

  When the jack portion 1e moves forward, the first propulsion / traction jack 12 is left in a relief state and returned at the same speed as the propulsion speed of the jack portion 1e. Further, when the outkey jack 17 is used at the time of propulsion of the front portion 1d, this pullback is performed. Then, the amount of bending can be secured by the extension stroke of the second propulsion / traction jack 13 and the forward direction can be corrected.

  Further, as a fifth step, the tail portion 1c is advanced by the second propulsion / traction jack 13 and the third propulsion / traction jack 14. At this time, since the tail portion 1c is directly connected to the front portion 1d by the third propulsion / traction jack 14, it can be easily retracted. Further, since the tail portion 1c is formed to be narrower than the jack portion 1e, no frictional resistance is generated between the tail portion 1c and the ground, and the second propulsion / traction jack 13 and the third The propulsion / traction jack 14 need only retract the weight of the tail portion 1c, and the propulsion / traction jack 14 can be facilitated.

  By repeating this process, a plurality of concrete boxes 4 are laid in columns.

  Thus, the front part 1d, the jack part 1e, and the tail part 1c, which are each divided body block, take the reaction force from other divided bodies by the extension and traction of the propulsion / traction jack, respectively, in the same manner as the ESA method. Advancing by self-propelled individually.

  Therefore, not only can each divided body change direction easily and curve construction is possible, it is basically unnecessary to apply a reaction force to the concrete box 4 at the rear, and a reaction wall is installed. Since the start pit is also unnecessary, construction is easy and the construction period can be shortened.

  In Patent Document 2, when the jack portion and the tail portion are moved forward, friction resistance can be reduced between the side ground and the ground can be reduced, but the self-propelled type of the conventional open shield machine is The blade edge resistance at the time of propulsion of the first block, which is the front part, is large, the propulsion of the front part requires a large thrust, and depending on the soil conditions etc., the front part cannot be advanced, or the jack part and the tail part The second block and the third block may move backward.

  In Patent Document 2, the friction of the front portion is reduced by using a friction cutter. However, only the bottom portion is considered, which is not sufficient. When the front portion moves forward, frictional resistance is also generated between the ground and the side.

  Therefore, the reaction force of the jack portion may be insufficient. In this case, it is necessary to provide an outkey jack and an outkey on the jack portion.

  Furthermore, when the reaction force is still insufficient with the out key, it is necessary to dispose a stopper jack, which is extended rearward and the tip abuts against the concrete box, so that the jack portion is moved forward when the front portion is advanced. And the tail part is prevented from returning backward.

  If such an outkey jack, outkey, or stopper jack must be provided, it is cumbersome and the construction procedure is complicated.

  The present invention eliminates the inconveniences of the above-mentioned conventional example, and the front shield, jack part, tail part of the three-part body block, or the two-part body block constitutes the body of the open shield machine, and the reaction force from the other part body blocks We provide an open shield method and an open shield machine that can easily advance the front part when moving forward independently using the same method as the ESA method (ENDLESS SELF ADVANCING METHOD) There is to do.

  In order to achieve the above object, according to the present invention, as an open shield construction method, the machine body is made up of first, second, and third divided body blocks that become a front part, a jack part, and a tail part, and the front part and the jack part are provided with a first part. Use an open shield machine that connects with the first propulsion / traction jack, and connects the jack and tail with the second propulsion / traction jack, and the front part is friction due to its own weight and earth pressure between the jack and tail The jack is moved forward by using the first propulsion / traction jack and the second propulsion / traction jack as a reaction force to the front portion and the tail portion. Is an open shield construction method in which the second propulsion / traction jack is actuated to pull the front block and the jack block into the reaction force and pull forward with the second propulsion / traction jack. In this case, the side part and the bottom part of the front part are divided in the length direction, and a slide jack is provided on the divided side part member and bottom part member, and when the front part is advanced, the divided side part member and The bottom member is moved forward sequentially by using the slide jack as the reaction force against the frictional resistance caused by the weight of the jack and tail and the earth pressure, or the airframe is used as the first and second divided blocks that become the front and tail. , Using an open shield machine in which the front part and tail part are connected by a propulsion / traction jack, and the front part is advanced with the tail part's own weight and the friction resistance due to earth pressure as reaction force, and the tail part is the front part's In the open shield construction method in which the division block is moved forward with a propulsion / traction jack as a reaction force, the side and bottom parts of the front part Are divided in the length direction, and a slide jack is provided on the divided side member and bottom member, and when the front part is advanced, the divided side member and bottom member are moved by the slide jack and the weight of the tail part and the soil are reduced. The gist is that the frictional resistance due to the pressure is made to proceed sequentially with the reaction force.

  As an open shield machine, the fuselage is the first, second, and third divided blocks that become the front part, jack part, and tail part, and the front part and jack part are connected by the first propulsion / traction jack, In the open shield machine that connects the jack part and the tail part with the second propulsion / traction jack, the side part and the bottom part of the front part are divided in the length direction, and slide to the divided side part and bottom part In an open shield machine with a jack, or an open shield machine in which the airframe is made up of first and second divided body blocks that form a front part and a tail part, and the front part and tail part are connected by a propulsion / traction jack. The side and bottom members are divided in the length direction, and slide jacks are provided on the divided side and bottom members, and the front A front opening portion of the rising from the bottom plate, it is an gist that the sediment holding plate for engaging detachably provided on the shoring extends open shield machine width direction.

  According to the first to fourth aspects of the present invention, the edge resistance during propulsion of the front portion, which is the first divided block in the self-propelled type of the conventional open shield machine, is large, and the propulsion of the front portion is greatly propelled. Prevents problems that thrust is required and the front part cannot move forward depending on the soil conditions, etc., and the jack part that is the second divided body block and the tail part that is the third divided body block may be retracted. Therefore, by dividing the side and bottom members of the front part in the length direction, the edge resistance at the time of propelling the front part is divided, and the propulsion and movement of the front part can be ensured.

  According to this invention of Claim 5, by providing the earth-and-sand control board so that attachment or detachment is possible, after the completion of one cycle of work process, from the start of the next process or from the end of one day of work to the start of the next day of work. By installing this earth-and-sand holding plate in between, when there is a possibility that the earth and sand in front of the face may collapse, it is possible to prevent the earth and sand from entering backward. In addition, the front support where the earth and sand control plate is installed moves forward, and at the same time, the front ground can be consolidated and stabilized.

  As described above, the open shield construction method and the open shield machine of the present invention are composed of a front part, a jack part, a three-part block of a tail part, or a two-part block to form an open shield machine body, When the reaction force is taken from the body block and the ESA method (ENDLESS SELF ADVANCING METHOD) “infinite self-propelled forward construction method” is used to advance individually and advance, the front part can be easily advanced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a partially cutaway cross-sectional plan view showing a first embodiment of the open shield method and open shield machine of the present invention, FIG. 2 is a longitudinal side view of the same, and FIG. 3 is a cross-sectional view taken along line AA in FIG. 4 is a cross-sectional view taken along the line BB of the same as above, and the same components as those in FIGS.

  The open shield machine 1 divides the machine body into a plurality of parts in the front-rear direction, and in this embodiment, the front part 1d having a blade edge 11 at the tip, the jack part 1e, and the tail part 1c on which the concrete box 4 is suspended are provided. Divided into divided blocks.

  The first propulsion / traction jack 12 'is provided between the front part 1d as the first divided body block and the jack part 1e as the second divided body block, and the jack part 1e and the third divided body block. A second propulsion / traction jack 13 'is disposed between the tail portion 1c and the tail portion 1c. For these propulsion / traction jacks 12 'and 13', pin jacks whose end portions are pivotally mounted are used. The first propulsion / traction jack 12 ′ and the second propulsion / traction jack 13 ′ are provided in two rows parallel to the left and right of the open shield machine 1 and with a plurality of stages above and below.

  The front part 1d, which is the first divided block, divides the side wall plate 1a and the bottom plate 1b, which are side and bottom members, in the length direction, and these divided side members 1a-1 to 1a-3 and The bottom members 1b-1 and 1b-2 can be moved relative to the support 6 which is the framework of the open shield machine 1, and slide jacks 3-1 to 3-3 (side slide jacks), 5-1 5-2 (lower slide jack) is provided and can be pushed out by this slide jack.

  The slide jacks 3-1 to 3-3, 5-1, and 5-2 are pin jacks that pivotally mount end portions thereof, and one end is pivotally attached to the support 6 and the other end is respectively attached. The side members 1a-1 to 1a-3 and the bottom members 1b-1 and 1b-2 are pivotally attached. These slide jacks 3-1 to 3-3, 5-1 and 5-2 are also provided in two rows in parallel to the left and right of the open shield machine 1.

  An earth-and-sand holding plate 10 that rises from the bottom plate 1b and extends in the open shield machine width direction and engages with the foremost supporter 6 is detachably provided at the front opening portion of the front portion 1d.

  The earth and sand holding plate 10 is made of a steel plate, and can be detachably disposed by dropping from above as necessary. The earth and sand control plate 10 and the bottom plate 1b (the bottom members 1b-1 and 1b-2) are not locked.

  As an example of detachable, a vertical groove is formed along the foremost support work 6, and the left and right of the earth and sand control plate 10 are inserted into the vertical groove so as to be a trap door.

  For the open shield method using such an open shield machine 1, the principle of promotion of the flowchart of FIG. 6 is shown, and each process is shown in FIGS.

  As shown in FIG. 7, the forward method of the open shield machine 1 is as shown in FIG. 1a-3, the uppermost side member 1a-1 is pushed out by extending the slide jack 3-1. At this time, the supporting work 6 takes a reaction force, but the supporting work 6 is held by the jack part 1e and the tail part 1c via the propulsion / traction jacks 12 'and 13'. The reaction force is taken with the tail portion 1c.

  Next, as shown in FIG. 8, the middle side member 1 a-2 is pushed out by extending the slide jack 3-2, and as shown in FIG. 9, the bottom side member 1 a-3 is pushed out by the slide jack 3-3. Extend 3 and press.

  As shown in FIG. 10, the slide jacks 5-1 and 5-2 are extended on either the left or right side of the bottom members 1b-1 and 1b-2 obtained by dividing the bottom plate 1b of the front portion 1d in the length direction. Press in order.

  As shown in FIG. 11, the propulsion / traction jack 12 'is extended and the support 6 of the front portion 1d is pushed out against the jack portion 1e and the tail portion 1c by taking a reaction force. At this time, if the slide jacks 3-1 to 3-3, 5-1 and 5-2 are free, the side members 1 a-1 to 1 a-3 and the bottom members 1 b-1 and 1 b-2 that have already advanced. On the other hand, the support work 6 can be moved relatively to form the front portion 1d having the original shape.

  After the forward movement of the front portion 1d, as shown in FIG. 12, the propulsion / traction jack 12 'is reduced, and the propulsion / traction jack 13' is extended to cause the front portion 1d and the tail portion 1c to react with each other. Next, the jack part 1e is pushed.

  As shown in FIG. 13, the propulsion / traction jack 13 'is fixed, the propulsion / traction jack 13' is reduced, and the tail portion 1c is propelled by traction. The reaction force at this time is taken from the front part 1d and the jack part 1e.

  The concrete box 4 is laid in the tail part 1c, but the tail part 1c has no bottom plate. First, the crushed stone 7 is laid, and the dry concrete 8 is disposed thereon to create a mound. The concrete box 4 is laid on it.

  In addition, if the earth and sand holding plate 10 is disposed as necessary, it is possible to perform this operation after the end of one cycle of work process until the start of the next process, or from the end of one day of work to the start of the next day. By installing the earth and sand holding plate 10, when there is a possibility that the earth and sand in front of the face may collapse, it is possible to prevent the earth and sand from entering backward.

  In addition, the support 6 of the front portion 1d on which the earth and sand restraining plate 10 is installed moves forward, and at the same time, the earth and sand in the front can be consolidated and stabilized by the earth and sand restraining plate 10.

  By repeating this process, the open shield machine 1 in which the machine body is divided into a plurality of parts in the front-rear direction is propelled, and a plurality of concrete boxes 4 are laid in a column.

  14 to 16 show a second embodiment of the present invention, in which the body of the open shield machine 1 is not a three-part block of a front part, a jack part and a tail part, but a front part having a blade edge 11 at the tip. 1d and the concrete box 4 were constituted by a two-part block of a tail part 1c from which the box was suspended.

  A propulsion / traction jack 12 'is disposed between the front portion 1d, which is the first divided body block, and the tail portion 1c, which is the second divided body block. This propulsion / traction jack 12 'uses a pin jack whose end is pivotably mounted.

  As in the first embodiment, the front portion 1d, which is the first divided block, divides the side wall plate 1a and the bottom plate 1b, which are side and bottom members, in the length direction, and these divided side members. 1a-1 to 1a-3 and the bottom members 1b-1 and 1b-2 can be moved relative to the supporting work 6 which is a framework of the open shield machine 1, and slide jacks 3-1 to 3-3 (sides) Part slide jacks), 5-1 and 5-2 (lower slide jacks) are provided and can be pushed out by the slide jacks.

  The slide jacks 3-1 to 3-3, 5-1, and 5-2 are pin jacks that pivotally mount end portions thereof, and one end is pivotally attached to the support 6 and the other end is respectively attached. The side members 1a-1 to 1a-3 and the bottom members 1b-1 and 1b-2 are pivotally attached.

In the first opening portion of the front portion 1d, the earth-and-sand holding plate 10 that rises from the bottom plate 1b, extends in the width direction of the open shield machine and engages with the foremost support 6 is detachably provided. This is the same as the embodiment.

  About the open shield method using such an open shield machine 1, the promotion principle of the flowchart of FIG. 19 is shown, and each process is shown in FIGS.

  As shown in FIG. 20, the open shield machine 1 is advanced as a first step, as shown in FIG. 20. 1a-3, the uppermost side member 1a-1 is pushed out by extending the slide jack 3-1. At this time, the reaction force is applied by the support work 6, but the support work 6 is pressed by the tail portion 1c via the propulsion / traction jack 12 ', so that the reaction force is finally applied by the tail portion 1c.

  Next, as shown in FIG. 21, the middle side member 1 a-2 is pushed out by extending the slide jack 3-2, and as shown in FIG. 22, the lowermost side member 1 a-3 is pushed out by the slide jack 3-3. Extend 3 and press.

  As shown in FIG. 23, the slide jacks 5-1 and 5-2 are extended on either the left or right side of the bottom members 1b-1 and 1b-2 obtained by dividing the bottom plate 1b of the front portion 1d in the length direction. Press in order.

  As shown in FIG. 24, the propulsion / traction jack 12 'is extended and the support 6 of the front portion 1d is pushed out against the tail portion 1c with a reaction force. At this time, if the slide jacks 3-1 to 3-3, 5-1 and 5-2 are free, the side members 1 a-1 to 1 a-3 and the bottom members 1 b-1 and 1 b-2 that have already advanced. On the other hand, the support work 6 can be moved relatively to form the front portion 1d having the original shape.

  After the forward movement of the front portion 1d, as shown in FIG. 25, the propulsion / traction jack 12 'is reduced, and the tail portion 1c is propelled by using the front portion 1d as a reaction force.

  A concrete box 4 is laid in the tail portion 1c. As shown in FIG. 18, the tail portion 1c has no bottom plate. First, a crushed stone 7 is laid, and a dry concrete 8 is disposed thereon. Then, a mound is created, and the concrete box 4 is laid on it.

  By repeating this process, the open shield machine 1 in which the machine body is divided into a plurality of parts in the front-rear direction is propelled, and a plurality of concrete boxes 4 are laid in a column.

1 is a partially cutaway plan view showing a first embodiment of an open shield method and an open shield machine of the present invention. It is a vertical side view which shows 1st Embodiment of the open shield construction method and open shield machine of this invention. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. It is explanatory drawing which shows 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a flowchart which shows 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 1st process of 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 2nd process of 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 3rd process of 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 4th process of 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 5th process of 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 6th process of 1st Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 7th process of 1st Embodiment of the open shield construction method and open shield machine of this invention. FIG. 5 is a partially cutaway plan view showing a second embodiment of the open shield method and the open shield machine of the present invention. It is a vertical side view which shows 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is AA sectional view taken on the line of FIG. It is the BB sectional drawing of FIG. It is explanatory drawing which shows 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a flowchart which shows 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 1st process of 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 2nd process of 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 3rd process of 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 4th process of 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 5th process of 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a vertical side view which shows the 6th process of 2nd Embodiment of the open shield construction method and open shield machine of this invention. It is a top view of a prior art example. It is a vertical side view of a prior art example. It is a longitudinal front view partly cut away of the conventional example.

DESCRIPTION OF SYMBOLS 1 ... Open shield machine 1a ... Side wall plate 1a-1 to 1a-3 ... Side member 1b ... Bottom plate 1b-1, 1b-2 ... Bottom member 1c ... Tail part 1d ... Front part 1e ... Jack part 3-1-3 -2 ... Slide jack 4 ... Concrete box 5-1 and 5-2 ... Slide jack 6 ... Supporting work 7 ... Crumble 8 ... Dry concrete 10 ... Sediment control plate 11 ... Blade 12, 12 '... First propulsion / Traction jacks 13, 13 '... second propulsion / traction jack 14 ... third propulsion / traction jack 15 ... friction cutter 16 ... out key 17 ... out key jack 18 ... stopper jack 19 ... friction cutter jack

Claims (5)

The airframe is made up of first, second and third divided blocks that become the front part, jack part and tail part, and the front part and jack part are connected by the first propulsion / traction jack, and the jack part and tail part are connected. Is used with a second propulsion / traction jack, and the front part is advanced with the frictional resistance caused by the dead weight and earth pressure of the jack part and the tail part as the reaction force. The propulsion / traction jack and the second propulsion / traction jack are used to move forward by extending the reaction force against the front part and tail part. In the open shield construction method in which the division block of the jack part is used as a reaction force to move forward with the second propulsion / traction jack and move forward,
The side part and bottom part of the front part are divided in the length direction, and a slide jack is provided on the divided side part and bottom part,
When the front part is advanced, the divided side member and bottom member are sequentially advanced by using a slide jack with the weight of the jack part and tail part and the frictional resistance caused by earth pressure as reaction forces. . The airframe is made up of the first and second divided blocks that are the front and tail, and an open shield machine is used in which the front and tail are connected by a propulsion / traction jack. In the open shield method where the frictional resistance due to earth pressure is advanced as a reaction force, and the tail part is moved forward by a propulsion / traction jack with the division block at the front part as a reaction force,
The side part and bottom part of the front part are divided in the length direction, and a slide jack is provided on the divided side part and bottom part,
An open shield construction method characterized in that when the front portion is advanced, the divided side member and bottom member are sequentially advanced by using a slide jack while the frictional resistance caused by the weight of the tail portion and earth pressure is applied as a reaction force. The airframe is made up of first, second and third divided blocks that become the front part, jack part and tail part, and the front part and jack part are connected by the first propulsion / traction jack, and the jack part and tail part are connected. In an open shield machine that connects with a second propulsion / traction jack,
An open shield machine characterized in that a front side member and a bottom member are divided in a length direction, and a slide jack is provided on the divided side member and bottom member. In the open shield machine where the machine body is the first and second divided body blocks that become the front part and the tail part, and the front part and the tail part are connected by a propulsion / traction jack,
An open shield machine characterized in that a front side member and a bottom member are divided in a length direction, and a slide jack is provided on the divided side member and bottom member.   The open shield machine of Claim 3 or Claim 4 which provided the earth-and-sand holding board which stood | started up from the baseplate in the front part opening part of the front part, extended in the open shield machine width direction, and latched to a support work.

Images