JP2005163381A - Shield machine, enlarged construction method for shield tunnel and reduced construction method for the shield tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a construction method for a shield tunnel capable of facilitating the construction of a safe and economical standard tunnel and an enlarged tunnel regardless of the depth, acting earth pressure/hydraulic pressure of a tunnel, shortening a construction period of time and reducing a construction cost. <P>SOLUTION: The first shell split body 7x and the second shell split body 7y consisting of first and second skin plates 8x and 8y divided into two parts and a ring girder can be rotated with the axis of a hinge 13 inserted in a crown section Ac as the center, and the enlargement of a shape of the shell by rotating it to the outside and the reduction of a shape of the shell by rotating it to the inside are carried out. Accordingly, first and second shield machine split bodies Ax and Ay dividing a tunnel excavator body equipped with the first and second shell split bodies 7x and 7y can also reduce or enlarge a cross section by the same operation, and the shield machine has such a constitution that the cross section can be freely enlarged and reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a shield excavator having an expansion function capable of excavating both a standard cross-section pit and a widening pit.

  The general shield method is equipped with a cutter and its drive device in front of the shield excavator body, a segment assembly machine that builds a lining with segments behind, and a propulsion device that advances the excavator in the middle. Is covered with a substantially cylindrical skin plate stiffened by a ring girder, the cutter is rotated by the drive device in the front, the shield excavator is advanced by the propulsion device, and the segments are assembled at the rear to cover the lining. Building a shield tunnel while building.

  Such shield tunnels are becoming increasingly important, especially in tunnel structures such as roads and railways in urban areas, and there is an increasing demand for long-distance excavation and deepening. Often, a widened donnel is required. For example, in the case of a railway tunnel such as a subway, a station section must be provided every 500m to 1000m. In the case of a road tunnel, an emergency parking zone or an acceleration / deceleration lane for branching must be provided about every 500m. This is due to circumstances such as not becoming.

Conventional methods for building widened sections in tunnels include excavation methods, methods for excavating and covering widened pits by partially removing segments after building a standard mine shield tunnel with a predetermined cross section, or dedicated to widened pits A construction method using a shield excavator has been implemented.
Japanese Patent No. 2677903

  Under such circumstances, the open-cut method has a large influence on the surrounding environment, such as occupying the land for a long period of time, and the construction becomes very large. Moreover, in the construction method in which the segment is partially removed after the shield tunnel is built and the widening pit is excavated and covered, it is wasteful to remove the once covered segment, and ground improvement against soil pressure is required. Furthermore, in the construction method using the shield excavator dedicated to the widening pit, work such as disassembly / conveyance and assembly of the shield excavator must be accompanied. As described above, the conventional method requires a great deal of labor and cost and leads to a prolonged construction period. For this reason, it has been desired to develop an economical shield excavator having a function of expanding an arbitrary part of the tunnel route to a predetermined required cross section and returning a necessary extension to the original cross section after excavation.

  The present invention has been made in view of the above circumstances, and it is easy to build a safe and economical standard tunnel and an enlarged tunnel regardless of tunnel depth, working earth pressure, water pressure, etc. It is an object of the present invention to provide a shield excavator, a shield tunnel expansion construction method, and a shield tunnel reduction construction method that can reduce the construction cost.

 The shield excavator according to claim 1 includes a standard tunnel portion whose required cross section is constructed in a standard pit, and an enlarged tunnel portion constructed in a widening pit whose required cross section is larger than that of the standard tunnel portion. A shield excavator constructed continuously in the direction of excavation, the cutter excavating both the standard tunnel portion and the enlarged tunnel portion in the front portion, the driving device of the cutter in the middle portion, and the propulsion for moving the shield excavator forward The apparatus comprises a segment assembly machine for constructing a lining with segments at the rear, a substantially cylindrical skin plate covering the outer peripheral surface of the shield excavator body, and a ring garter arranged along the inner peripheral surface of the skin plate An outer shell, and a partition wall that divides the front portion and the middle portion of the shield excavator, and the outer shell includes a dividing line and a outer shell arranged so as to straddle a cross section thereof. The dividing wall is divided into two by two cutting lines connecting the intersections, and the partition is also divided into two by dividing lines arranged so as to straddle the cross section of the outline, and one of the intersections of the dividing lines and the outline is connected. A hinge extending in the axial direction of the shield excavator is disposed on the cutting line of the shield, and the divided outer shell is connected via the hinge, so that the cross-section of the outer shell can be enlarged and reduced through the hinge. It is characterized by being composed.

  The shield excavator according to claim 2, wherein a cutting line connecting the other intersection point of the dividing line and the outer shell is centered on an axis of a hinge installed at a cutting line connecting one intersection point of the dividing line and the outer shell. It arrange | positions in the range of the said outer shell formed in the circular arc which carries out.

  The shield excavator according to claim 3, wherein the outer shell is divided into two left and right via a pair of cutting lines, and is connected via the hinges arranged on the one cutting line. Each of the first outer divided body and the second outer divided body, and a cutter is provided in each of the first outer divided body and the second outer divided body. It is divided into shield excavator divided bodies and connected through the hinges.

  The shield excavator according to claim 4, wherein the outer shape has a longitudinal shape and a member length centered on the hinge in order to close an opening formed in the outer shape when the divided outer shape is enlarged. A plurality of eaves formed on the arc of the outer shell, the eaves on the inner peripheral surface of the outer shell at a predetermined portion formed in an arc centered on the hinge, the longitudinal direction of the outer case A portion of the saddle that is arranged so as to straddle both the first outer divided body and the second outer divided body along the circumferential direction and overlaps with the inner peripheral surface of the first outer divided body A tunnel excavator shaft that fixes the anchorage member fixed to the outer shell divided body and another anchor member that fixes the portion of the anchorage overlapping the inner peripheral surface of the second outer shell divided body to the outer shell divided body. It is characterized in that a plurality of tunnel excavators are continuously connected in the linear direction over the entire length of the tunnel excavator.

  The shield excavator according to claim 5 is characterized in that a power device is provided for applying a pressing force in the circumferential direction to the dredged material.

  7. The shield excavator according to claim 6, wherein a longitudinal direction is formed in the outer shell in a circular arc centered on the hinge in order to close an opening formed in the outer shell when the divided outer shell is enlarged. The cover plate is provided at a predetermined portion formed in an arc centered on the hinge, the longitudinal direction being along the circumferential direction of the outer shell, and the first outer divided body and the first outer divided body. It arrange | positions so that both of 2 outline division bodies may be straddled.

  The shield excavator according to claim 7 is provided with a power device that applies a pressing force in a circumferential direction to the divided body between the first outer divided body and the second outer divided body. It is characterized by that.

  9. The shield excavator according to claim 8, wherein when the divided outline is expanded, a longitudinal direction is provided on a rear surface of the partition so as to close an opening formed in the partition that is divided along with the expansion. A plurality of curved beams formed in an arc whose radius is the distance between the installation position and the hinge, and the curved beams are on the saddle material on the back surface of the partition wall, Stacked so that the longitudinal direction is aligned with the circumferential direction of the outer shell and wraps with both the first partition wall segment and the second partition wall partition body at a predetermined portion formed in an arc centered on the hinge. A curved beam that fixes the curved beam portion that overlaps the back surface of the first partition wall segment, and the curved beam portion that overlaps the back surface of the second partition wall body. Cross with another curved beam fixed to the partition wall in the vertical direction. It is characterized by a plurality of connecting over the entire height of the partition wall back into.

  The shield excavator according to claim 9, wherein an opening of the partition divided into two parts by a straight line connecting the intersections of the two cutting lines and the partition has a hinge installed on the one cutting line. One side of the partition wall, in which one end side of a folded plate structure in which sides of a plurality of fan-shaped members having substantially the same radius as the outer shell formed by an arc centered on an axis are connected by a hinge is cut in two And the other end side of the folded plate structure is connected to the other cut side of the partition wall cut into two through the hinge.

  The shield excavator according to claim 10, wherein one intersection of the dividing line and the outer shell is provided at the top of the outer shell, and the other intersection is provided on the outer shell corresponding to the invert portion of the tunnel. It is a feature.

  The method for enlarging and constructing a shield tunnel according to claim 11 is for a shield tunnel using a shield excavator having an outer divided body that can be enlarged via a hinge provided on an outer shell of the shield excavator and a cutter at the front of the shield excavator. It is an expanded construction method, and after expansion, the excavator is advanced along the expanded cross-section portion in advance with the cutter, and after filling the surplus portion with a filler, the segment for the widening pit is smaller than the end face thickness of the segment. Enlarging the outer shell segment by widening and expanding the segment for the widening pit by an amount smaller than the end face thickness of the segment, expanding the outer shell segment, assembling the segment and shield excavator This is characterized in that the digging is sequentially repeated until a predetermined enlarged cross section is obtained.

  The shield tunnel reduction construction method according to claim 12 is a shield tunnel using a shield excavator having an outer division body that can be reduced via a hinge provided on an outer shell of the shield excavator and a cutter at the front of the shield excavator. This is a reduced construction method, and in the reduction, the reduced width pit segment is assembled by reducing it by an amount smaller than the end face thickness of the segment, the outer divided body is reduced, and the filling material is filled in the gap portion generated in the reduction. The shield excavator is dug in such a manner that the reduced assembly of the segments, the reduction of the outer divided body, and the excavation of the shield excavator are sequentially repeated until a predetermined reduced cross section is obtained.

  According to the shield excavator of the first aspect, the divided outer shells are connected via the hinges so that the outer shell cross-section is configured to be freely enlarged. The reduction operation can be performed smoothly.

  According to the shield excavator according to claim 2, the cutting line connecting the other intersection point of the dividing line and the outer shell is formed into an arc centering on the axis of the hinge installed on the cutting line connecting the one intersection point. Even if the left and right semi-cylindrical parts of the shield excavator are rotated outward or inward with the hinge structure as the center, the hinge structure and the bottom of the shield excavator Since the distance of the skin plate does not change, the shape of the invert part itself does not change although the length in the circumferential direction changes. Therefore, in addition to the arch portion and the arch leg portion of the tunnel, the same shape segment can be used in the standard well and the enlarged well in the invert portion.

  According to the shield excavator of the third aspect, since the outer divided body is divided into left and right parts, it can be suitably used in the case of scaling up and down in the left and right direction substantially over the entire cross section.

  According to the shield excavator of claim 4, the tunnel excavator is disposed so as to straddle both the first outer divided body and the second outer divided body when the outer shell is enlarged. Because it is configured to be closed with multiple connected slabs over the entire length of the shell, it can cover the open part of the outer shell that occurs when the shield excavator is expanded, and shield excavation of mud, mud, groundwater, etc. generated during excavation It is possible to prevent leakage into the aircraft. In addition, by arranging the brazing material in the open part, it will function as a stiffening member for the outer shell, and it is possible to improve the rigidity and load bearing capacity of the skin plate that has a shape that combines open sections It becomes.

  According to the shield excavator according to claim 5, since the dredging material is provided with a power device that acts on the circumferential direction, the earth pressure acting on the shield excavator divided into two parts, The water pressure is balanced and rotated around the axis of the hinge structure, and the axial force introduced into the arc member gradually shifts to the skin plate, and eventually to the outer shell, so that the skin plate of the shield excavator becomes a saddle structure. The boundary conditions are adjusted so that the design is possible, and the rigidity and load resistance of the skin plate can be increased.

  According to the shield excavator according to claim 6, the opening when the outer shell is enlarged is closed with the cover plate arranged so as to straddle both the first outer shell divided body and the second outer shell divided body. As a result of this configuration, it is possible to cover the open part of the outer shell that occurs when the shield excavator is expanded, and it is possible to prevent leakage of mud, mud, groundwater, etc., generated during excavation into the shield excavator .

  According to the shield excavator according to claim 7, since the cover plate is provided with a power device that applies a pressing force in the circumferential direction, earth pressure acting on the shield excavator divided in two, The water pressure is balanced and rotated around the axis of the hinge structure, and the axial force introduced into the arc member gradually shifts to the skin plate, and eventually to the outer shell, so that the skin plate of the shield excavator becomes a saddle structure. The boundary conditions are adjusted so that the design is possible, and the rigidity and load resistance of the skin plate can be increased.

  According to the shield excavator according to claim 8, one intersection of the dividing line and the outer shell is provided at the top of the outer shell, and the other intersection is provided on the outer shell corresponding to the invert portion of the tunnel. Since the hinge is provided in the crown portion, a part of earth pressure, water pressure, etc. acting on the first outer divided body and the second outer divided body divided into two substantially semi-cylindrical parts. Can be balanced through the hinge structure.

According to the shield excavator according to claim 9, since the obstruction of the opening of the partition wall is a folded plate structure connected to the end of the partition wall, interference with a device such as a cutter attached to the partition wall is reduced. It becomes possible.

According to the shield excavator of claim 10, since the outer divided body can be enlarged and reduced in the horizontal direction left and right, the enlarged cross section is widened in the left and right, and is suitably used for emergency parking zones such as road tunnels and branch junctions. Will be.

According to the method for enlarging and building a shield tunnel according to claim 11, since the cross-sectional enlargement amount between adjacent rings is smaller than the segment end face thickness, no opening is formed on the end face of the widening pit segment, and the opening is closed. No separate measures are required.

According to the method for reducing and constructing a shield tunnel according to claim 12, since the cross-sectional reduction amount between the adjacent rings is smaller than the segment end face thickness, no opening is generated in the end face of the reduced-width shaft segment, and this opening is blocked. No separate measures are required.

  The shield excavator according to the present invention will be described in detail below with reference to the drawings shown in FIGS. The present invention excavates cross sections of different sizes from the standard mine to the enlarged mine of the required cross-sectional area, and constructs linings of different sizes from the standard mine to the enlarged mine inside the shield excavator, A shield excavator having a function of performing a series of operations continuously and smoothly is shown.

  Hereinafter, the axis of the shield excavator in the digging direction of the shield excavator is referred to as a shield excavator axis, and a cross section perpendicular to the shield excavator axis is referred to as a cross section of the shield tunnel excavator.

(Name of each part of shield excavator)
As shown in FIG. 1 (a), the shield excavator A constructs a lining B by assembling a cutter 1 for excavating the soil layer in front of the shield excavator A at the front Af and a segment 2 at the rear Ar. The segment assembly machine 3 to perform, the segment shape holding device 4 for holding the shape of the lining immediately after assembly, the cutter driving device 5 for driving the cutter 1 to the intermediate portion Am, and the reaction force by pressing the lining B And a propulsion device 6 for moving the shield excavator A forward.

On the other hand, the outer side of the shield excavator A described above is covered with an outer shell 7, and the outer shell 7 is installed in a substantially cylindrical skin plate 8 covering the outer side of the shield excavator A, in front of and in the center of the skin plate 8. In addition, the skin plate 8 is stiffened from the inside and provided with front and intermediate ring girders 9f and 9m on which the propulsion device 6 and the like are installed.
The shield excavator A includes a hood part (front part) Af for excavating the inside of the outer shell 7 with the cutter 1 in front of the shield excavator A and a rear part of the shield excavator A. It is divided into a tail part (rear part) Ar for constructing the lining B by the segment assembling machine 3 and an intermediate part Am in the middle where the cutter driving device 5 and the propulsion device 6 are installed. The part Am is defined by a partition wall 10 supported by the front ring girder 9f.

As shown in FIG. 1B, the top portion of the outer shell 7 constituting the shield excavator A described above is a crown portion Ac, the left and right arc-shaped portions connected to the crown portion are arch portions Aax, Aay, and the bottom portion. The left and right portions connecting the invert portion Ai, the arch portions Aax, Aay and the invert portion Ai are referred to as arch leg portions Asx, Asy.
In general, the shape of the skin plate 8 constituting the outer shell 7 of the shield excavator A is circular because the shield excavator A is placed in deep soil and a strong external force such as earth pressure or water pressure acts from the surrounding ground. There are many examples of adopting a closed cross-sectional structure. The shape of the skin plate 8 constituting the outer shell 7 of the shield excavator A is not circular, but the cross-sectional shape of the arch portions Aax and Aay is an arc shape, and the cross-sectional shape of the skin plate 8 at the invert portion Ai is also the crown portion Ac. Is a circular arc with a radius Ri. The cross-sectional shapes of the arch leg portions Asx and Asy connecting the arc-shaped portions of the arch portions Aax and Aay and the arc of the invert portion Ai are arc-shaped curves that smoothly connect the two curves.

(Expansion function of shield excavator A)
As shown in FIG. 2A, the outer shell 7 including the substantially cylindrical skin plate 8 having the above-described shape is one intersection of the dividing line 11 and the outer shell 7 arranged so as to cross the cross section of the outer shell 7. Shield excavation with two cutting lines 12cc and 12ci obtained by connecting 11cc on the crown part Ac and the other intersection 11ci on the invert part Ai and connecting the continuous intersections arranged on the outer shell 7 respectively. Cut along the axis. In this way, not only the skin plate 8 but also the front and middle ring girders 9f and 9m that stiffen the skin plate 8 from the inside are cut at the same position, so that the outer shell 7 has a semi-cylindrical first outer shell. It is divided into two parts, a divided body 7x and a second outer divided body 7y. Accordingly, the skin plate 8 constituting the outer shell 7 is also connected to the first skin plate 8x and the second skin plate 8y, and the front and middle ring girders 9f and 9m are also respectively connected to the first front ring girder 9fx and the second skin girder 9fx. The front ring girder 9fy, the first intermediate ring girder 9mx, and the second intermediate ring girder 9my are divided. The shield excavator A is also provided with the above-described cutter 1, cutter driving device 5, propulsion device 6 and the like divided into the first outer divided body 7x and the second outer divided body 7y, respectively. Therefore, it is divided into the first shield excavator divided body Ax and the second shield excavator divided body Ay. As a matter of course, the partition wall 10 that separates the hood portion Af and the intermediate portion Am of the shield excavator A is also divided by the dividing line 11 into the first partition wall partition body 10x and the second partition wall partition body 10y.

In the shield excavator A, a hinge 13 extending in the axial direction of the shield excavator A is arranged on the cutting line 12cc arranged in the crown portion Ac, and the divided first and second outer shells are arranged. The divided bodies 7x and 7y are connected via the hinge 13. Therefore, the first shield excavator divided body Ax and the second shield excavator divided body Ay are also connected via the hinge 13. It becomes.
In the above description, it is assumed that one intersection 11cc of the dividing line 11 and the outer shell 7 is arranged on the crown portion Ac and the other intersection 11ci is arranged on the invert portion Ai. It will be arrange | positioned at the axis | shaft of the hinge 13 installed in this. Further, the axis of the hinge 13 in the crown portion Ac of the shield excavator A is arranged at the same position as the center of the arc forming the cross-sectional shape of the skin plate 8 in the invert portion Ai.

In the above, one intersection 11cc between the dividing line 11 and the outer shell 7 is arranged on the crown Ac, that is, the axis of the hinge 13, and the other intersection 11ci is arranged on the invert portion Ai. If the dividing line 11 arranged so as to cross the cross section is arranged such that the other intersection point 11ci is within the range of the outer intersection 7 formed in one arc 11cc, that is, an arc centered on the axis of the hinge 13. Any position may be used. Further, as shown in FIG. 2B, the intersection 11cc, that is, the other intersection 11ci of the dividing line 11 passing through the axis of the hinge 13 is centered on the one intersection 11cc on the outer shell 7, that is, the axis of the hinge 13. As long as it arrange | positions in the range formed in the circular arc, there may be two or more. Furthermore, as shown in FIG. 3, there may be any number of combinations of the intersection 11 cc, that is, the combination of the axis of the hinge 13 and the intersection 11 ci as long as the dividing line 11 connecting the intersections does not intersect inside the skin plate 8.
The intersection 11ci between the dividing line 11 dividing the outer shell 7 and the skin plate 8 of the invert part Ai and the intersection 11ci between the dividing line 11 dividing the partition wall 10 and the skin plate 8 of the invert part Ai are not necessarily the same. It doesn't have to be a position.

As shown in FIG. 4A, the crowns of the first and second skin plates 8x and 8y provided in each of the first outer divided body 7x and the second outer divided body 7y constituting the outer shell 7. The end sides 8xt and 8yt located at the portion Ac are connected to both sides of the hinge 13 inserted into the crown portion Ac. The ring girder 9f, 9f that is provided in each of the first outer divided body 7x and the second outer divided body 7y and stiffens the skin plate 8 from the inner side is divided into two. The end sides of the first and second front ring girders 9fx, 9fy and the crown portions Ac of the first and second intermediate ring girders 9mx, 9my are also connected to both sides of the hinge 13. .
As a result, the force acting on the cutting line 12 cc of the left and right outline divisions is balanced through the hinge 13. At this time, the forces acting on the first and second front ring girders 9fx and 9fy and the first and second intermediate ring girders 9mx and 9my divided into two are transmitted via the hinge structure 13. As shown in FIGS. 5 (a) and 5 (b), the ends of the first and second ring girders 9f and 9m connected to the hinges 13 are successively raised as shown in FIGS. Is set smaller and the digit width is set larger.

  As shown in FIG. 4 (b), the first and second skin plates 8x, 8y and the first and second front ring girders 9fx, 9fy, and The first outer divided body 7x and the second outer divided body 7y made of the second intermediate ring girder 9mx, 9my are connected via the hinge 13 inserted in the crown portion Ac, so that the shaft of the hinge 13 can be connected. The shape of the outer shell 7 can be enlarged by rotating outward, and the shape of the outer shell 7 can be reduced by rotating inward. Accordingly, the first and second shield excavator divisions Ax and Ay obtained by dividing the shield excavator A into two parts are connected via the hinge 13 so that the cross section can be freely enlarged and reduced. It will be.

  The shield excavator A can be provided with a structure that allows the cross section to be freely enlarged and reduced as described above, but the cross section of the shield excavator A is enlarged as shown in FIG. Then, an opening GS is generated between the cutting line 12ci of the outer shell 7, that is, between the first outer divided body 7x and the second outer divided body 7y, and the 0 dividing line of the partition wall 10, that is, the partition wall dividing body 10x, Since the opening GB is generated even during 10y, it is essential to close the openings GS and GB in order to make the shield excavator A practical.

(First embodiment for closing the opening of the outer shell)
One method of closing the opening GS when the intersection 11ci of the dividing line 11 and the invert part Ai of the outer shell 7, that is, the cutting line 12ci is installed at the center of the invert part Ai will be described below.
The outer shell 7 of the shield excavator A has a length substantially equal to the arc length of the inverted portion Ai of the shield excavator A and the shape thereof is the axis of the hinge 13 as shown in FIG. A member 14 having a radius Rr as a center and having a lower edge shape which is the same as the upper edge of the skin plate 8 of the portion is provided. The dredging material 14 constitutes the first and second outer divided bodies 7x and 7y in the invert portion Ai so that the longitudinal direction is perpendicular to the axis of the shield excavator, that is, along the circumferential direction of the outer shell 7. The first skin plate 8x and the second skin plate 8y are disposed on the upper surfaces of the first and second skin plates 8x and 8y.
At this time, the brazing material 14 includes a brazing material 14e that fixes a portion 14efx of the brazing material overlapping the inner peripheral surface of the first outer division body 7x to the outer division body 7x, and the second The shield excavation in the axial direction of the shield excavator at a position where it does not interfere with another rib 14f fixing the portion 14ffx of the dredging that overlaps the inner peripheral surface of the outer division 7y to the outer division 7y. They are alternately connected over the entire length of the machine with a predetermined gap interval.

As a result, even when the first outer divided body 7x and the second outer divided body 7y rotate outwardly about the hinge 13 and the opening GS is generated between the two, the opening GS becomes the full length. It will be covered with the curved surface which the some brazing materials 14e and 14f connected over are comprised.
That is, as shown in FIG. 6 (b), the shield excavator divisions Ax and Ay constituting the shield excavator A have the width of the open portion GS formed in the invert portion Ai with the axis of the hinge 13 as the center. Even when the outer shell 14 is rotated outward with a limit of half the length of the saddle member 14, it is between the first outer divided body 7x and the second outer divided body 7y located in the invert part Ai. Since the opening GS is covered and closed by the curved surface formed by the dredging material 14, an opening is generated between the first skin plate 8x and the second skin plate 8y of the shield excavator A. There is no.

For the purpose of preventing muddy water, groundwater, etc. generated by excavation work in the shield excavator A from entering the inside of the shield excavator A from the gap between the adjacent dredgers 14e and 14f. In this case, a seal structure (not shown) is employed, and a gap between adjacent saddle members 14e and 14f is ensured to have a minimum size necessary and sufficient for installing the seal structure.
Further, as shown in FIGS. 6 (a) and 6 (b), end portions of the portions 14efx and 14ffx of the eaves 14e and 14f fixed to the skin plates 8x and 8y are arch leg portions Asx and Asy, or the arches. The arch portion Aax, Aay connected to the leg portion Asx, Asy is reduced in its member height, and further, the saddle material used for the invert portion Ai of the tail portion Ar of the shield excavator A for assembling the segment 2 For 14, the upper edge is also an arc centered on the axis of the hinge structure 13.

In the above, the shield excavator A is divided into the first and second shield excavator divisions Ax and Ay in order to enable the cross-section of the shield excavator A to be enlarged and reduced, and the skin excavator A is provided. The outer shell 7 is a combination of members having an open cross section divided into two semi-cylindrical portions of the first and second outer shell divided bodies 7x and 7y. For this reason, as for the shield excavator A, bending rigidity, shear rigidity, and torsional rigidity as a whole are lowered. In particular, the first and second skin plates 8x and 8y in the invert portion Ai have a plate structure in which two sides are free ends in the hood portion Af and tail portion Ar, and one side is free end in the intermediate portion Am. Therefore, compared with the skin plate of the invar ridge portion in a general shield excavator A having a cylindrical closed cross-sectional structure, the decrease in rigidity and load resistance is remarkable.
However, in the present embodiment, as shown in FIG. 6, a plurality of dredging materials 14e and 14f are provided in the axial direction of the tunnel excavator A with respect to the first and second skin plates 8x and 8y in the inverted portion Ai. The outer shell 7 is configured by being installed and fixed. For this reason, the dredging material 14 in the invert portion Ai of the shield excavator A in the present embodiment has not only the function of closing the open portion GS of the shield excavator A but also the stiffening effect of the skin plate 8 in the invert portion Ai. Will also have.

As a matter of course, the dredging material 14 is deformed by earth pressure or groundwater pressure acting on the invert part Ai of the shield excavator A, but the dredging materials 14e and 14f arranged alternately are fixed. Since the first and second skin plates 8x and 8y are substantially bilaterally symmetric, the deformation of the collar members 14e and 14f is also substantially bilaterally symmetric. For this reason, the saddle members 14e and 14f are not only deformed in the out-of-plane direction of the curved surface formed by the saddle member 14 due to the load, but also deformed in the out-of-plane direction of the adjacent curved beams 14e and 14f. Since this may impair the function of the sealing structure, it is necessary to have a structure that restrains the displacement of the deformation between the adjacent saddle members 14e and 14f to each other. There is. On the other hand, the mechanism for restraining each of the adjacent saddle members 14e and 14f has a function of increasing the rigidity of the saddle member 14, and consequently, increases the rigidity of the outer shell of the invert portion Ai and improves the load resistance. Will have the effect of

The collar member 14 has one end portion 14efr of the collar member 14e not fixed to the first skin plate 8x, and 14ffx fixed to the second skin plate 8y of the collar member 14f adjacent thereto. And a power unit 15 for rotating the shield excavator divided bodies Ax and Ay of the shield excavator A around the axis of the hinge structure 13.
As a result, the first outer divided body 7x and the second outer divided body 7y constituting each of the first and second shield excavator divided bodies Ax and Ay divided in two are subjected to earth pressure / The water pressure is balanced through the hinge structure 13 inserted in the crown portion Ac of the shield excavator A and the power unit 15 installed in the plurality of anchors 14 arranged in the invert portion Ai.

  Further, in the invert portion Ai, the collars 14e and 14f fixed alternately to the first and second skin plates 8x and 8y are formed on the first and second outer divided bodies 7x and 7y in the invert portion Ai. Not only the stiffening effect but also the axial force introduced into 14e and 14f via the power unit 15 gradually causes the first and second skin plates 8x and 8y, and thus the first and second outer divisions. Move to the body 7x, 7y. As a result, the rigidity of the entire shield excavator A is increased, and the load resistance of the first outer divided body 7x and the second outer divided body 7y is remarkably improved.

(Second embodiment for closing the opening of the outer shell)
In 1st Embodiment which obstruct | occludes the opening part of the outer shell 7, when both the 1st and 2nd shield excavator division bodies Ax and Ay are rotated outside about the shield excavator A, the first The configuration in which the opening GS between the outer shell divided body 7x and the second outer shell divided body 7y is closed via the plurality of ribs 14 is shown. In the second embodiment in which the opening of the outer shell 7 is closed, the plate is replaced between the first outer shell divided body 7x and the second outer shell divided body 7y in place of the saddle member 14 so as to straddle both. A configuration for installing the structure and closing the opening GS is shown below.
In this embodiment, the intersection 11ci between the dividing line 11 and the outline 7 at the invar portion, that is, the position of the cutting line 12ci need not be limited to the center of the invert Ai.

As another method for closing the opening GS formed between the first outer divided body 7x and the second outer divided body 7y, a cover plate 16 is used as shown in FIG. Can do. The cover plate 16 is formed with an arc similar to the inverted portion Ai of the skin plate 8 in the longitudinal direction, and the depth direction is formed in the same manner as the entire length of the outer shell 7.
In this case, when the other intersection 11ci of the dividing line 11 and the outer shell 7, that is, the cutting line 12ci is near the center of the skin plate of the invert part Ai, the cover plate 16 supported by a device (not shown) is The skin plate 8x constituting the first outer divided body 7x and the skin plate 8y constituting the second outer divided body 7y are arranged along the circumferential direction of both and straddling both.
In addition, as shown in FIGS. 7C and 7D, when the other intersection 11ci between the dividing line 11 and the outer shell 7, that is, the cutting line 12ci is in the vicinity of the arch leg Asy of the invert Ai, the arch leg A member 17 is attached to the cut portion of the skin plate 8y on the Asy side in order to provide a step having a predetermined dimension inside or outside the shield excavator A, and the cover plate 16 is attached to the skin plate 8 of the invert portion Ai. Install in parallel.
The cover plate 16 may be configured to be installed on either the inner peripheral surface side or the outer peripheral surface side of the skin plate 8, as shown in FIGS. 7 (a), (b), (c), and (d). Moreover, it is good also as a structure arrange | positioned on both an inner peripheral surface and an outer peripheral surface.

The cover plate 16 forms a wrap structure having a required interval with the skin plate 8 of the invert part Ai, and a sealing structure (not shown) is arranged in the wrap structure, so that muddy water and groundwater for the shield excavator A, etc. Is to prevent leakage.
Therefore, the distance between the two when the cover plate 16 is arranged on the outer shell 7 is set to a minimum dimension necessary and sufficient to prevent leakage of muddy water, muddy water and groundwater into the shield excavator in the wrap structure. Shall be kept.

In addition, the length of the cover plate 16 in the curved surface direction, that is, the circumferential direction of the outer shell 7, is limited to the length of the inverted portion Ai of the skin plate 8, but in this case the tunnel cross section of the shield excavator A The maximum amount of widening Δr is the member length in the curved surface direction of the cover plate 16, that is, in the circumferential direction of the outer shell 7.
In order to rotate the first and second shield excavator divisions Ax and Ay of the shield excavator A around the axis of the hinge structure 13, the first and second also in this embodiment. It is necessary to install a power unit (not shown) between the shield excavator divided bodies Ax and Ay divided bodies.

With such a configuration, the shield excavator divisions Ax and Ay included in the shield excavator A are rotated outward with the member length in the curved surface direction of the cover plate 16, that is, in the circumferential direction of the outer shell 7 as a limit. In this case, since the opening GS generated between the outer shell divided bodies 7x and 7y is covered and closed by the cover plate 16, no opening is generated in the inverted portion Ai of the shield excavator A. .
In addition, the closing method of the opening GB between the outer divided bodies 7x and 7y is not limited to the above two methods.

(First embodiment for closing an opening of a partition wall)
One method of closing the opening GB of the partition wall 10 when the intersection 11ci between the partition line 11 of the partition wall and the outline 7 at the invert section Ai is installed at the center of the invert section Ai will be described below.
As shown in FIGS. 8 (a) and 8 (b), the members of the shield excavator A are arranged on the rear surfaces of the left and right first and second partition walls 10x and 10y of the shield excavator A. The distance between the axis of the hinge 13 and the position where the member is installed is defined as a radius, with the shape being substantially equal to the inner dimension of the outer shell 7 at the position where it is installed, A curved beam 18 is provided.
The curved beam 18 includes the first partition wall 10x of the partition wall 10 and the second partition wall in a direction perpendicular to the shield excavator axis, that is, a direction parallel to the circumferential direction of the outer shell 7 in the invert part Ai. Stacked from the upper edge of the brazing material 14 of the inverted portion Ai behind the partition wall 10 to the upper end of the partition wall 10 so as to wrap around both the divided bodies 10y.
At this time, as shown in FIG. 8 (c), the curved beam 18 has a curved beam portion 18mfx that overlaps the inner peripheral surface of the first partition wall 10x as the first partition wall 10x. A curved beam 18m that is fixed, and another curved beam 18n that fixes a portion 18nfy of the curved beam overlapping the inner peripheral surface of the second partition wall segment 10y to the second partition wall segment 10y; Are connected alternately in the height direction of the bulkhead 10 of the shield excavator A at a position where they do not interfere with each other with a predetermined gap interval over the entire height of the bulkhead 10.

Thus, even when the first outer divided body 7x and the second outer divided body 7y rotate outwardly around the hinge 13 and an opening GB is generated between them, FIG. As shown in FIG. 2, the opening GB is covered with a plane formed by a plurality of curved beams 18 connected over the entire height.
The widths of the overlapping portions of the curved beams 18m and 18n that close the opening GB of the first and second partition walls 10x and 10y are equal to the width of the first and second partition walls of the curved beams 18m and 18n. In order to allow the shield excavator A to excavate an expanded mine having a widened width as much as possible, the length of the curved beam 18 is a shield excavator. It is desirable to make it as long as possible within a range that does not interfere with other structural parts of A.

In a general shield excavator, the cutter and the cutter driving device are installed in the partition girder and the ring girder supporting the partition. In the shield excavator A, the cutter 1 and the cutter driving device 5 are also provided in the partition 10. More specifically, the first and second partition wall segments 10x and 10y and the front ring girder 9f supporting the partition wall 10 are installed. Therefore, when the opening GB of the partition wall partitions 7x and 7y is closed by the curved beams 18m and 18n, the beam height of the curved beam 18 is set to a height that can be used by the cutter driving device 5, and at the same time, the first In the arrangement of the cutter 1 and the cutter driving device 5 on the second partition wall segments 10x and 10y, care must be taken so as not to interfere with the curved beams 18m and 18n.
Further, the outer divided bodies 7x and 7y rotate outwardly around the hinge structure 13, so that muddy water and groundwater generated by excavation work in the shield excavator A are shielded from the gap between the adjacent curved beams 18m and 18n. For the purpose of preventing the inside of the excavator A from entering, the curved beam 18 employs a seal structure (not shown), and ensures a minimum dimension sufficient to install the seal structure. And

As a matter of course, the curved beam 18 is deformed out of the plane of the curved beams 18m and 18n by the pressure of mud, mud, etc. stored in the hood portion Af of the shield excavator A. There will be a deviation in the deformation of the matching curved beams 18m, 18n in the out-of-plane direction. Since this may impair the function of the above-described seal structure, it is necessary to provide a mechanism that suppresses the displacement of the deformation between the adjacent curved beams 18m and 18n out of the plane. Therefore, a mechanism (not shown) is provided on the overlapping surface of the curved beams 18m and 18n so that the out-of-plane deformation of the curved beams is substantially the same. For example, uneven surfaces may be formed on the overlapping surfaces of the curved beams 18m and 18n in the extending direction of the beams so as to be slidable.
Such a mechanism for restraining the deformation of each of the adjacent curved beams 18m and 18n also has a function of increasing the rigidity of the curved beam 18, and consequently has an effect of improving the load bearing capacity of the partition wall 10. Therefore, the first embodiment for closing the opening of the partition wall can correspond to a shield excavator having a large cross section.

(Second embodiment for closing the opening of the partition wall)
In the first embodiment in which the opening of the partition wall is closed, when the shield excavator A rotates both the shield excavator segment Ax and Ay outward, the first partition segment 10x and the first The structure which closed the opening part GB produced between the 2 partition division bodies 10y via the some curved beam 18 was shown. In the second embodiment in which the opening of the partition wall is closed, a foldable folded plate structure 21 is provided between the first partition wall dividing body 7x and the second partition wall partitioning body 7y instead of the curved beam 18. Another method of the configuration in which the opening GB is closed by installing is shown below.
In this embodiment, the position of the intersection 11ci between the dividing line 11 of the partition wall 10 and the outline 7 of the invar portion Ai need not be limited to the central portion of the invert Ai.

The opening GB of the partition wall 10 has a sector shape having the same radius as the upper edge of the collar 14 located on the back surface of the partition wall as shown in FIGS. A folded plate structure 21 is provided in which the respective sides in the radial direction of the plurality of members 19 that have been cut are connected by hinges 20, and one end side 21x of the folded plate structure 21 is connected to one partition wall 10x. In the state where the other end side 21y of the folded plate structure 21 is connected to the cut end side via the hinge structures 22x and 22y to the cut end side of the other partition wall 10y and the opening GB is closed. In a state where the plate structure 21 is folded and the first outer divided body 7x and the second outer divided body 7y rotate outwardly about the hinge 13 and the opening GB is opened, the folded plate structure 21 is The opening GB is closed by being developed.
The folded plate structure 21 tends to be deformed backward by the pressure of mud, mud water, etc. stored in the hood part Af of the shield excavator A, but the deformation of the folded plate structure 21 is restrained against this. A separate mechanism is required.

In this embodiment, the front end portion of the folded plate structure 21 is cut off with a radius r, and a separate opening is generated. This opening is blocked by the first and second partition walls 10x and 10y. The partition wall portion of the portion to be stretched can be closed by a method such as extending in the circumferential direction around the hinge 13 to form a wrap structure. Further, a seal structure (not shown) is employed between the folded plate structure 21 and the saddle member 14.
In addition, the cutter 1 and the cutter driving device 5 are installed in the first and second partition dividing bodies 10x and 10y and the ring girders 9fx and 9fy supporting the partition 10, but the opening of the partition is formed. According to the second method of closing, there is little possibility of interference with a device or the like that closes the opening GB in a portion where the device or the like is mounted. .
Of course, the closing method of the opening GB between the partition walls 10x and 10y is not limited to the above two methods.

(Example of cutter used for shield excavator)
By the way, in front of the shield excavator A, there is provided a cutter 1 capable of excavating both a standard mine and an enlarged mine having a required cross-sectional area. The cutter 1 includes a surface slab cutter used when excavating a circular cross section and a peripheral extra digging mechanism, a spoke cutter capable of excavating an arbitrary cross section, and an extra digging mechanism at the outer circumference and the center. It is considered that some of the commonly used cutters such as a frame-type cutter that translates and rotates eccentrically with a multi-axis machine can be applied. The ratio differs depending on the ratio of enlargement with respect to, the arrangement position of the dividing line dividing the partition 10, the method for closing the opening of the partition 10, and the like.
As described above, the shield excavator A is shielded at two locations in the center of the crown portion Ac of the shield excavator A and the invert portion Ai facing the shield excavator A in order to excavate the expanded pit following the standard mine excavation. Cut along the axial direction of the excavator, insert a hinge 13 into the cut portion of the crown part Ac, and divide the first and second shield excavator divisions Ax and Ay divided into two into hinges 13 respectively. The first and second shield excavator divisions Ax and Ay can be rotated about the axis of the hinge 13 and the cross section of the shield excavator A can be enlarged / reduced. As a result, the partition wall 10 for attaching the cutter 1 and the cutter driving device 5 is also divided into the first and second partition wall segments 10x and 10y. Cutter 1 and cutter drive device 5 in de excavator A be divided into two, the respective first and second partitions divided body 10x, those capable of exhibiting the required functions and device 10y desirable.
In the following, the eccentric multi-axis translation provided with a surplus excavation mechanism that seems to be suitable for a shield excavator A having a large cross section with a large enlargement ratio adopting the first embodiment for closing the opening of the partition wall 10. The configuration when the rotating frame cutter 1f is employed will be described in detail.

In general, the eccentric multi-axis translational and rotating frame type cutter 1f has a cutter head with a cutter bit mounted on a frame having a shape substantially similar to the excavation cross section, and the cutter is eccentrically supported by a plurality of rotation shafts. By rotating the shaft in the same direction, the cutter head is translated and rotated to excavate a tunnel having a required cross-sectional shape.
Therefore, in the shield excavator A, as shown in FIG. 10, the eccentric multi-axis translational frame cutter 1f is divided into two widening excavation cutters 1fx and 1fy, and an extra excavation mechanism is provided for each. A configuration in which the cutter driving device 5 that is mounted and driven is also divided into two left and right cutter driving devices 5x and 5y, and attached to the first and second partition wall divisions 10x and 10y divided into two on the left and right sides, respectively. And

That is, a cutter head equipped with a cutter bit (not shown) is divided into a right and left frame on a frame having a shape substantially similar to that of a standard pit, and the arch portion Aax of the tunnel excavator A is used as an outer peripheral excavation mechanism on the cutter head. , Aay and an arch leg Asx, Asy, a frame having the same shape as the Asy, and an overcutter with a cutter bit attached to the cutter head, the upper end is a hinge that can be rotated to the left and right, and the overcutter is appropriately attached to the lower end In order to excavate a portion that cannot be excavated when the first and second shield excavator divided bodies Ax and Ay are rotated outward about the hinge 13, the cutter is attached. Frame-type cutters 1fx and 1fy, each equipped with a central re-cutting mechanism having the same function as the outer peripheral re-cutting mechanism on the head, respectively Supported eccentrically by a plurality of rotating shafts, in which the rotary shaft by translation and rotation of the cutter head by rotating in the same direction to drill the required cross-section.
When the opening of the partition wall 10 is closed by adopting the first embodiment, the first partition wall segment 10x and the curved beam 18f, and the second partition wall partition 10y and the curved beam 18e overlap. Since the positional relationship changes relatively in the portion, the cutter driving device cannot be installed in this portion.
Further, the excavation of the outer peripheral portion and the center portion of the frame type cutter head 1f in the excavation of the expanded mine is not limited to the method of the frame type cutter head 1fx and 1fy, and the excavator provided in addition to the frame type cutter head It is good also as a structure which excavates an extra carved part by etc.

(Construction of widening pit)
An excavation method for excavating by expanding or reducing the excavation section continuously after excavating the standard mine using the shield excavator A described above will be described below.

(Standard digging)
When excavating a standard mine with the shield excavator A, as shown in FIG. 1 (a) and FIG. 10, first, as a first step, the shape of the frame type cutter 1f is adjusted so that the standard cross section can be excavated. Next, as a second step, the segment type 2s is used for the standard mine by driving the frame type cutter 1f with the cutter driving power unit 5 and pressing the existing lining B with the propulsion unit 6 of the shield excavator A. As a third step, the segment 2s for the standard mine is assembled using the segment assembly machine 3 at the tail part Ar behind the excavator A and covered with the segment shape holding device 4 as a third step. One cycle of constructing the lining B while maintaining the shape of the construction B is completed.
As shown in FIG. 11 (a), the standard mine segment 2s includes a top segment 2sc located at the crown portion Ac of the tunnel, an invert portion segment 2si located at the invert portion Ai of the tunnel, and an arch portion of the tunnel. And an arch leg segment 2sa and an arch leg segment 2ss located in the arch leg.

(Expansion of excavation cross section)
As described above, the enlargement of the excavation cross section by the shield excavator is performed by connecting the first and second outer divided bodies Ax and Ay divided into two via the hinge 13 inserted in the crown portion Ac. The outer divided body is rotated outwardly about the 13 axis to enlarge the cross section of the first and second outer divided bodies Ax, Ay of the shield excavator A. Therefore, the amount of widening of each part of the shield excavator is proportional to the distance from the hinge 13 inserted into the crown part Ac, and is maximum at the arch leg part.
While the shield excavator A excavates one ring of the lining, the widening amount (enlargement amount) at the arch leg portion of the shield excavating machine A blocks the gap between the skin plate 8 and the lining at the location. The tail seal (not shown) installed for the purpose can be adjusted, and the widening amount per ring is about 5 cm to 10 cm in total width.
With such a widening (enlarging) amount, the thickness is smaller than the thickness at the end face of the segment 2, so that no opening occurs even when the segment end face is displaced between adjacent segment rings during enlargement. Therefore, it is not necessary to take a separate measure such as a wife member that closes the opening on the segment end face. Since the tail seal is within the adjustable range, the widening segment 2e can be assembled before the first outer divided body 7x and the second outer divided body 7y are enlarged. Is simplified.

Below, the procedure in the case of enlarging an excavation cross section continuously following the excavation of the above-mentioned standard cross section using the shield excavator A is shown in FIGS.
The following steps are carried out as the first stage.
As a first step, the outer peripheral excavation mechanism of the frame-type cutter 1f is extended by an amount corresponding to the widening amount per ring of the lining B without enlarging the outline of the shield excavator A, and the shield The propulsion device 6 of the excavator A presses the existing standard mine lining B, and the cutter 1 is translated and rotated by the cutter drive power device 5 to excavate the required cross-sectional area, which corresponds to the width of the segment 2s. After digging the length, the segment 2s for the standard mine is assembled using the segment assembly machine 3 at the tail part Ar behind the excavator A, and the shape of the lining B is held by the segment shape holding device 4. Complete one cycle of building B.
Hereinafter, the same operation is repeated L / b times when the length of the shield excavator A in the tunnel axis direction is L and the width of the standard mine segment 2s is b. In addition, when L / b is not an integer, the minimum integer multiple exceeding L / b may be used as the value of L / b.

As a result, on the side surface in the vicinity of the front end of the shield excavator A, an extra excavation of L / b times the amount of widening per ring of the segment 2 occurs. On the side surface in the vicinity of the rear end of the shield excavator A, the segment 2 Excessive excavation corresponding to the amount of widening per ring was made. It should be noted that a filler Z is injected into a gap portion between the side surface of the shield excavator A and the soil layer, which is generated as a result of overdigging, to prevent the soil layer from collapsing.
Note that the maximum widening width per unit length when the widening pit is dug by the shield excavator A is a value obtained by dividing the tail clearance by one ring length of the segment 2S. However, the extra moat for enlarging the cross section of the tunnel may not be enlarged stepwise for each length of the ring as described above, but may be gradually enlarged so as to include the enlarged cross section along with the excavation.

Next, as a second stage after the time when the gap between the side surface of the shield excavator A and the soil layer near the rear end of the shield excavator A becomes the widening amount per ring of the segment 2s, The following steps are performed.
First, in the first step, the shield excavator divided bodies Ax and Ay constituting the shield excavator A are rotated outwardly by an amount corresponding to the widening amount per segment ring around the axis of the hinge structure 13. As a result, the cross section of the shield excavator A is enlarged by an amount corresponding to one ring widening amount. Further, at this time, the filler Z (not shown) injected between the skin plate 8 and the soil layer of the shield excavator A is taken into the shield excavator A for the widening, and is expanded in the second step. Using the segment assembling machine 3 at the tail portion Ar of the shield excavator A, the widening pit segment 2e whose cross section is enlarged by an amount corresponding to the widening amount per ring is assembled, and the shape is formed using the segment shape holding device 4. In the third step, the newly constructed lining Be is pressed by the propulsion device 6 to dig one ring of the widening pit segment 2e. To complete one cycle of widening pit construction.
Hereinafter, the expansion of the first and second outer divided bodies 7x and 7y of the shield excavator A, the expansion assembly of the segment 2, and the excavation of the shield excavator A are repeated until a predetermined enlarged cross section is obtained. Incidentally, although it is the said repeating process, since the expansion amount per ring is within the adjustment range of the tail seal, the first and second outer divided bodies 7x, 7y are first assembled after the segment 2 is expanded and assembled first. The shield excavator A may be excavated while expanding or expanding.
The first and second shield excavator divisions Ax and Ay constituting the shield excavator A are rotated outwardly by an amount corresponding to the widening amount per segment ring around the axis of the hinge structure 13. Each frame is divided into two and the frame type cutter 1f is also rotated outward at the same time. Therefore, it is not necessary to newly extend the outer peripheral excavation mechanism of the cutter 1f.

As shown in FIG. 11B, the widening pit segment 2e is composed of a top segment 2ec, a bottom segment 2ei, an arch segment 2ea, and an arch leg segment 2es, similar to the standard mine segment 2s. Among them, the top segment 2 e is slightly different from the top segment 2 s of the standard mine by rotating the first and second outer divided bodies 7 x and 7 y around the hinge 13, and the bottom segment 2 ei is also centered on the hinge 13. When the outer divided body is rotated, the circumferential extension thereof is increased from that of the standard well, and it is necessary to increase the length of a part of the segment 2ei.
Moreover, about the arch part segment 2ea and the arch leg part segment 2es, compared with the preceding lining segment of the same position, the deviation according to the widening amount of each position is produced in proportion to the distance from the hinge 13. Become. Therefore, in the widening pit segment 2e, if the above-mentioned deviation is not a problem in terms of strength, water stoppage performance during construction or after lining construction, the arch segment 2ec, the bottom segment 2ei, and the arch leg segment 2es In particular, a segment having the same structure and dimensions as those of the segment 2s for the standard mine in which the segment end face is not provided with a separate measure such as a wife member can be used.
However, when the widening pit segment 2e has a problem in terms of strength or water-stopping performance due to the above-described deviation, the width and length of the widening pit segment 2e are the same even if the width and length are the same. And it is necessary to use the one that takes necessary measures for the position of the water seal.

Next, as a third stage after the point when the excavation area in front of the shield excavator A becomes a predetermined cross section, the following steps are performed.
That is, prior to the first step of the second stage, the outer peripheral excavation mechanism of the frame type cutter 1f is reduced by an amount corresponding to one ring widening amount, and then the same process as the second stage is performed. Repeat until the mechanism is restored to standard mine excavation. When the outer peripheral excavation mechanism of the frame type cutter 1f is restored to the state of standard excavation, there is no gap between the side surface of the shield excavator A and the soil layer over the entire length of the shield excavator A. The shield excavator A can continuously excavate the target widening pit.

(Reduction of excavation cross section)
FIGS. 13A to 13F show a procedure in the case where the excavation section is reduced continuously following the above-described excavation of the enlarged section using the shield excavator A that can be enlarged or reduced.
First, in the first step, the segment assembly machine 3 is used at the tail part Ar of the expanded shield excavator A, and the cross section is reduced by an amount corresponding to the reduction width per ring from the lining constructed immediately before. The widened pit segment (width-reducing segment) 2e is assembled, and the shape is held using the segment shape holding device 4 to construct the lining Be.
Here, the amount corresponding to the amount of reduction (reduction) per ring is substantially the same as the amount of enlargement (enlargement amount) per ring at the time of widening, and the tail seal of the shield excavator A can be adjusted. The range is about 5 cm to 10 cm in total width. If the amount of expansion is such a degree, the thickness is smaller than the thickness at the end face of the segment 2, so that no opening is generated even if the segment end face is displaced between adjacent segment rings when the width is reduced. Therefore, it is not necessary to take a separate measure such as a wife member that closes the opening on the segment end face. Further, since the tail seal is within the adjustable range, the width reducing segment 2e can be assembled before the first and second outer divided bodies 7x and 7y are reduced, so that the width reduction process is simplified. .
In the second step, when the shield excavator A is slightly advanced to reach the widening pit segment 2e where the tail end rear end Ar is reduced, the shield excavator splits Ax and Ay constituting the shield excavator A are Then, the section of the shield excavator A is reduced by an amount corresponding to one ring widening amount by rotating inwardly by the amount corresponding to the reduction width per segment ring around the axis of the hinge structure. At the same time, the cutter 1 is rotated by the driving device, and the newly constructed lining Be is pressed by the propulsion device 6 to dig and dig for one ring of the widening pit segment 2e. In the above operation, the reduction of the cross section of the shield excavator A and the excavation may be performed simultaneously. At this time, a gap is formed between the skin plate 8 of the shield excavator A and the soil layer, and this gap is filled with a filling material Z as a normal backing material.

  Hereinafter, the reduction assembly of the segment 2, the reduction of the first and second outer divided bodies 7x and 7y, and the excavation of the shield excavator A are repeated until a predetermined reduced cross section is obtained.

  According to the configuration described above, the shield excavator A is configured such that the first and second outer divided bodies 7x and 7y obtained by dividing the outer shell 7 are connected via the hinge 13 so that the cross section of the outer shell 7 can be enlarged. Therefore, enlargement / reduction is caused by rotation, and enlargement / reduction operations can be performed smoothly.

  Further, a cutting line connecting the other intersection point 11ci of the dividing line 11 and the outer shell 7 is an outer shell formed in an arc centering on the axis of the hinge 13 placed on the cutting line 12cc connecting the one intersection point 11cc. 7, the first shield excavator divided body Ax and the second shield excavator divided body Ay that are substantially semi-cylindrical on the left and right sides of the shield excavator A with the hinge structure as the center. Or, even if it is rotated inward, the distance between the hinge structure and the skin plate at the bottom of the shield excavator does not change, so the shape of the invert part itself does not change although the length in the circumferential direction changes. Therefore, in addition to the arch portion and the arch leg portion of the tunnel, the same shape segment can be used in the standard well and the enlarged well in the invert portion.

  Furthermore, since the outer divided body is divided into the left and right sides of the first outer divided body 7x and the second outer divided body 7y, it can be preferably used when the entire cross section is enlarged or reduced in the horizontal direction. It becomes.

  Further, a plurality of openings when the outer shell 7 is expanded are arranged so as to straddle both the first outer shell divided body 7x and the second outer shell divided body 7y, and are continuously connected over the entire length of the tunnel excavator A. When the shield excavator A is expanded because the cover 14 is arranged so as to straddle both the first outer shell divided body 7x and the second outer shell divided body 7y. The open portion of the outer shell 7 that is generated can be covered, and it is possible to prevent leakage of mud, mud, groundwater, etc., generated during excavation into the shield excavator A. Further, by arranging the brazing material 14 in the open portion, it functions as a stiffening member of the outer shell 7 and improves the rigidity and load resistance of the skin plate 8 having a shape combining open sections. It becomes possible.

  At this time, since the dredging material 14 and the cover plate 16 are provided with a power device 15 that exerts a pressing force in the circumferential direction, the earth pressure and the water pressure that act on the shield excavator A divided in two are provided. The balance is rotated around the axis of the hinge structure, and the axial force introduced into the arc member gradually shifts to the skin plate 8 and eventually to the outer shell 7, so that the skin plate 8 of the shield excavator A The boundary conditions are adjusted so that the structure can be designed, and the rigidity and load resistance of the skin plate 8 can be increased.

  In addition, one intersection 11cc between the dividing line 11 and the outer shell 7 of the shield excavator A is provided at the top of the outer shell 7, and the other intersection 11ci is provided on the outer shell 7 corresponding to the invert portion of the tunnel. Since the hinge 13 is provided in the crown portion, earth pressure, water pressure, etc. acting on the first outer divided body 7x and the second outer divided body 7y divided into two substantially semi-cylindrical parts. A part of can be balanced through the hinge structure.

  Since the folded plate structure 21 in which the opening of the partition wall 10 constituting the shield excavator A is closed and connected to the end sides of the first partition body 10x and the second partition wall body 10y is attached to the partition wall 10. It is possible to reduce interference with a device such as the cutter 1.

  Since the first outer divided body Ax and the second outer divided body Ay constituting the shield excavator A can be expanded and contracted horizontally in the horizontal direction, the expanded cross section becomes wider in the left and right directions, emergency parking zones such as road tunnels, branches, etc. It will be suitably used for the junction.

  According to the method for enlarging the shield tunnel, the cross-sectional enlargement amount between adjacent rings is smaller than the thickness of the end face of the segment 2, so that no opening is formed on the end face of the widening pit segment 2e. Do not need.

  According to the reduced construction method of the shield tunnel, since the cross-sectional reduction amount between the adjacent rings is smaller than the end face thickness of the segment 2, no opening is formed in the end face of the reduced width pit segment 2e. No measures are required.

It is a figure showing the outline of the shield excavator concerning the present invention. It is a figure which shows the cross section of the outer shell which comprises the shield excavator which concerns on this invention. It is a figure which shows the deformation | transformation condition of the outer shell which comprises the shield excavator which concerns on this invention. It is a figure which shows the front of the shield excavator which concerns on this invention. It is a figure which shows the crown part of the outer shell which comprises the shield excavator which concerns on this invention. It is a figure which shows the dredger with which the outer shell which comprises the shield excavator which concerns on this invention was equipped. It is a figure which shows the cover plate with which the outer shell which comprises the shield excavator which concerns on this invention was equipped. It is a figure which shows the detail of the curved beam with which the outer division body which comprises the shield excavator which concerns on this invention was equipped. It is a figure which shows the folded-plate structure with which the partition which comprises the shield excavator concerning this invention was equipped. It is a figure which shows the detail of the cutter which comprises the shield excavator which concerns on this invention. It is a figure which shows the segment which concerns on this invention. It is a figure which shows the expansion construction method of the shield tunnel using the shield excavator which concerns on this invention. It is a figure which shows the reduction construction method of the shield tunnel using the shield excavator which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cutter 2 Segment 3 Segment assembly machine 4 Segment shape holding device 5 Cutter drive device 6 Shield excavator propulsion device 7 Outer shell 8 Skin plate 9 Ring girder 9f Front ring girder 9m Middle ring girder 10 Bulkhead 11 Dividing line 11cc In crown part Intersection 11ci of dividing line and outline 12ci Intersection of dividing line and outline at the invert portion 12cc Outer cutting line at the crown portion 12ci Outer cutting line at the invert portion 13 Hinge 14 Anchor 15 Power unit 16 Cover plate 17 Skin plate A member 18 connecting the cover plate and the curve plate 19 Curved beam 19 Partition opening closing member 20 Hinge 21 Folded plate structure 22x, 22y Hinge

A Shield excavator Af Shield excavator hood (front)
Am shield excavator middle part Ar shield excavator tail part (rear)
Ac Crown of the excavator Aax, Aay
Arch part Asx, Asy of shield excavator
Arch leg part Ai of shield excavator Invert part B of shield excavator Covering Z Filling material

Claims (12)

Shield excavation in which the standard tunnel part with the required cross section built in the standard mine and the enlarged tunnel part built in the widening pit with the required cross section enlarged compared to the standard tunnel part are continuously built in the tunnel excavation direction Machine,
A cutter for digging both the standard tunnel portion and the enlarged tunnel portion at the front, a driving device for the cutter and a propulsion device for advancing the shield excavator at the middle, and a segment assembly machine for constructing a lining with segments at the rear An outer shell made up of a substantially cylindrical skin plate covering the outer peripheral surface of the shield excavator body and a ring garter arranged along the inner peripheral surface of the skin plate, and a front portion and an intermediate portion of the shield excavator are partitioned A partition wall,
The outer shell is divided into two by two cutting lines connecting the intersections of the dividing line and the outer shell arranged so as to straddle the cross section, and the partition wall is also a dividing line arranged so as to straddle the outer cross section. A hinge extending in the axial direction of the shield excavator is arranged on one cutting line connecting the intersection of the dividing line and the outer shell, and the divided outer shell is connected via the hinge. Thus, the shield excavator is configured so that the cross-section of the outer shell can be enlarged and reduced via the hinge. The shield excavator according to claim 1,
A cutting line connecting the other intersection of the dividing line and the outer shell is an outer shell formed in an arc centered on an axis of a hinge installed at a cutting line connecting one intersection of the dividing line and the outer shell. A shield excavator characterized in that it is arranged within a range. The shield excavator according to claim 1 or 2,
The outer shell is divided into two right and left via a pair of the cutting lines, and the first outer shell divided body and the second outer shell divided by the hinges arranged on the one cutting line. Composed of the body,
Each of the first outer divided body and the second outer divided body is provided with a cutter, and the shield excavator is divided into two left and right shield excavator divided bodies and connected via the hinges. Shield excavator characterized by being. In the shield excavator according to any one of claims 1 to 3,
In order to close an opening formed in the outer shell when the divided outer shell is enlarged, the outer shell has a plurality of ribs formed in a circular shape centered on the hinge and having a longitudinal shape and a member length. Provided,
The brazing material is formed on the inner peripheral surface of the outer shell, on a predetermined portion formed in an arc centered on the hinge, with the longitudinal direction along the circumferential direction of the outer shell, and the first outer divided body and And arranged so as to straddle both of the second outer divided body,
The brazing material that fixes the portion of the brazing material that overlaps the inner peripheral surface of the first outer shell divided body to the outer shell split body, and the portion of the brazing material that overlaps the inner peripheral surface of the second outer shell dividing body A shield excavator characterized in that a plurality of other anchors fixed to the outer shell divided body are alternately connected in the axial direction of the tunnel excavator over the entire length of the tunnel excavator. The shield excavator according to claim 4,
A shield excavator characterized in that a power device for applying a pressing force in the circumferential direction to the dredged material is provided. The shield excavator according to any one of claims 1 to 3, wherein a longitudinal direction is provided in the outer shell and the hinge is provided in order to close an opening formed in the outer shell when the divided outer shell is enlarged. A cover plate formed on the center arc is provided.
The cover plate straddles both the first outer divided body and the second outer divided body at a predetermined portion formed in an arc centered on the hinge, with the longitudinal direction extending along the circumferential direction of the outer shell. Shield excavator characterized by being arranged as follows. The shield excavator according to claim 6,
A shield excavator characterized in that a power device is provided between the first outer divided body and the second outer divided body to apply a pressing force in the circumferential direction to the divided body. In the shield excavator according to any one of claims 1 to 3,
In order to close the opening formed in the partition wall that is divided along with the expansion when the divided outline is expanded, the back surface of the partition wall has a longitudinal shape and a member length, and its installation position. And a plurality of curved beams formed in an arc whose radius is the distance from the hinge,
The curved partition is formed on the rib on the back surface of the partition wall, with a longitudinal direction along a circumferential direction of the outer shell at a predetermined portion formed in an arc centered on the hinge, and the first partition partition body And stacked and arranged so as to wrap with both of the second partition wall partitions,
A curved beam that overlaps the back surface of the first partition wall segment is fixed to the partition wall body, and a curved beam portion that overlaps the back surface of the second partition wall body is fixed to the partition wall body. A shield excavator characterized in that a plurality of other curved beams are alternately connected in the vertical direction over the entire height of the rear surface of the partition wall. In the shield excavator according to any one of claims 1 to 3,
The opening of the partition divided into two parts by a straight line connecting the intersection of the two cutting lines and the partition was formed with an arc centered on the axis of the hinge installed on the one cutting line One end of a folded plate structure in which sides of a plurality of fan-shaped members having substantially the same radius as the outer shell are connected by a hinge is connected via a hinge to one cut side of the partition wall cut into two. The shield excavator is characterized in that the other end side of the folded plate structure is connected to the other cut side of the partition wall cut into two through a hinge. The shield excavator according to any one of claims 1 to 9,
A shield excavator characterized in that one intersection of the dividing line and the outer shell is provided at the top of the outer shell, and the other intersection is provided on the outer shell corresponding to the invert portion of the tunnel. A method for expanding and constructing a shield tunnel using a shield excavator having an outer shell division body that can be expanded via a hinge provided on an outer shell of the shield excavator and a cutter at the front of the shield excavator,
Before expanding, after excavating along the enlarged cross section with the cutter, and filling the surplus portion with a filler, the widening pit segment is widened by an amount smaller than the end face thickness of the segment, and the outer division is assembled. And expanding the segment for the widening pit by an amount smaller than the end face thickness of the segment, and digging the shield excavator, expanding the outer division, assembling the segment and digging the shield excavator for a predetermined amount A method for enlarging a shield tunnel, which is repeated until an enlarged cross section is obtained. A method of reducing and building a shield tunnel using a shield excavator having a shroud that can be shrunk via a hinge provided on the outer shell of the shield excavator and a cutter at the front of the shield excavator,
For the reduction, the reduced width pit segment is assembled by reducing the amount smaller than the end face thickness of the segment, the outer divided body is reduced, and the filling material is filled in the gap portion generated in the reduction, and the shield excavator is advanced. A method for reducing and constructing a shield tunnel, wherein the reduction assembly of the segments, the reduction of the outer divided body, and the excavation of the shield excavator are sequentially repeated until a predetermined reduced cross section is obtained.

Images