JP2008031642A - Connecting method of concrete case body and concrete case body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting method of a concrete case body capable of surely preventing the mutual dislocation of the concrete case bodies, particularly when thrust is nonuniformly applied to the joining end surface of the concrete case body, in curved construction or the like. <P>SOLUTION: A PC steel bar 21 is inserted into and bound to a gas pipe 12a by inserting and arranging the gas pipe 12a as a pipe material having an inner diameter of the substantially same diameter as the PC steel bar 21 and an outer diameter of the substantially same diameter as a sheath hole 12 into a sheath hole 12 for allowing the penetration of the PC steel bar 21 as a binding member. Various sizes are adapted to sizes of the gas pipe 12a and the PC steel bar 21 to be used, when a clearance between the gas pipe 12a and the PC steel bar 21 is extremely small. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention can be applied to an open shield method and a propulsion method for constructing underground structures such as water and sewerage systems, common ditches, telegraphs and telephones, etc. in urban areas, and is particularly suitable for a curved construction site. The present invention relates to a body connection method and a concrete box.

  The propulsion method and the open shield method are widely used as methods for constructing underground structures such as water and sewerage systems, common ditches, telegraphs and telephones, and other underground structures. With the propulsion method, a concrete box or a fume pipe is suspended and set in the excavation hole while excavating the face with an excavator, and the concrete box is pushed by a propulsion jack placed on the start pit. It is a method of burying concrete boxes etc. in columns in sequence by repeating the process of securing the space for setting the next concrete box etc. Usually, a blade or an excavator is installed in front of the top concrete box or the like.

On the other hand, the open shield method is a highly rational method utilizing the advantages of the open cut method (open cut method) and the shield method. For example, patent documents relating to the open shield method include the following.
JP 2006-112101 A JP 2006-112100 A

  The outline of the open shield machine 1 used in this open shield construction method is as shown in FIG. 5, with the front, rear and top surfaces comprising left and right side wall plates 1a and bottom plates 1b connected to these side wall plates 1a opened. The front ends of the side wall plate 1a and the bottom plate 1b are formed as blade edges 11, and the propulsion jacks 2 are arranged side by side up and down at the center or near the rear end of the side wall plate 1a. In the figure, 3 indicates a partition wall.

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

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

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

  Then, the second concrete box 4 is suspended in the tail part 1 c of the open shield machine 1 in front of the first concrete box 4. Thereafter, the same earth removal process, advance process, and concrete box 4 setting process are repeated as appropriate, and the concrete boxes 4 are sequentially left in the ground as the open shield machine 1 moves forward. Put backfill 5 on the upper surface of the body 4.

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

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

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

  The concrete box 4 is made of reinforced concrete and comprises a left side plate 4a, a right side plate 4b, an upper floor plate 4c, and a lower floor plate 4d as shown in FIG. In the figure, 12 is a sheath hole for inserting a PC steel bar as a fastening member that opens to the end surface 4e and fastens the front and rear concrete boxes 4, and 17 indicates a boxing for wearing a PC steel bar.

  Moreover, in order to ensure the strength of the concrete box 4, the corners are generally haunched so that the thickness of the concrete is large and the shape of the opening 10 is chamfered.

  In order to fasten the concrete boxes 4 left in the ground in a column by a fastening member such as a PC steel rod, first, the height of the concrete box 4 newly placed on the tail portion 1c of the open shield machine 1 is set. As shown in FIG. 7, the height adjustment material 7 is used, and the height of the sheath hole 12 with the concrete box 4 previously placed is matched. A grout material is poured under the newly placed concrete box 4.

  The previously placed concrete box 4 is fastened by a PC steel bar 21 penetrating the sheath hole 12, and its tip is shown in an enlarged view in FIG. It is fixed by 21a and nut 21b.

  Next, as shown in FIG. 9, a PC steel rod 21 is inserted between the newly placed concrete box 4 and the concrete box 4 placed before that, and temporarily tightened. Thereafter, the open shield machine 1 is moved forward by one piece of the concrete box 4 and the grout material is injected into the space formed by the advancement of the tail portion 1c.

  Thereafter, as shown in FIG. 10, the newly inserted PC steel rod 21 is fastened from the end face of the newly placed concrete box 4 on the side of the open shield machine 1 by the fastening jack 21 c. The binding jack 21c is provided with a connecting rod 21e, which is inserted into the sheath hole 12 of the concrete box 4 and connected to the newly inserted PC steel rod 21 by the coupler 21d as shown in FIG. The rotational force of the binding jack 21 c is applied to the PC steel rod 21 to bind the PC steel rod 21.

  By the way, when performing curved construction, as the open shield machine 1, the machine body is divided into a plurality of parts in the front-rear direction, and the use position and number of the propulsion jacks 2 are mainly changed as a half-folded structure that can independently change the direction. Proceed with directional control in the vertical and horizontal directions.

  As shown in FIG. 12, when the open shield machine 1 moves forward while drawing a reaction force on the concrete box 4, an unbalanced force is applied to the concrete box 4 with the left and right propulsion jacks 2. Or, as shown by the alternate long and short dash line, the open shield machine 1 is tilted with respect to the concrete box 4, so the force applied to the top concrete box 4 is not equal to the end surface, but eccentric thrust acts, A shift occurs between the joining end surfaces of the concrete boxes 4 that are in tandem.

  As a method for preventing such deviation, for example, as shown in FIG. 6, an insertion hole 13 is formed in the end face 4e of the concrete box 4, and a pin is inserted therein to connect the concrete boxes 4 to each other. A method of fixing the end faces can also be considered.

  In addition, the device of the countermeasure against such a shift | offset | difference between the concrete boxes 4 is not made conventionally, and there is no patent document related to it.

  However, when the degree of bending at the construction site is large, the eccentric thrust applied to the joint end face of the concrete box 4 becomes large, the pin cannot withstand the partial force, the pin is deformed, and the concrete around the insertion hole 13 is chipped. May occur, and there is a risk of misalignment of the joints between the concrete boxes.

  The object of the present invention is to eliminate the inconveniences of the conventional example, and in the case of curved construction, especially when the thrust is applied to the joint end face of the concrete box in a non-uniform manner, the connection of the concrete box can be surely prevented. It is to provide a method and a concrete box.

  In order to achieve the above object, the concrete box connecting method of the present invention is as follows. First, a concrete box which is sequentially arranged in a column for underground use and receives the thrust of a propulsion jack is connected to a PC steel bar or the like. In the method for connecting a concrete box to be fastened by a member, a pipe member having an inner diameter substantially the same diameter as that of the fastening member is fixedly disposed in a sheath hole through which the fastening member passes, and the fastening member is inserted into the pipe member and fastened. In addition, the use of a steel pipe as the pipe material, and thirdly, the boxing for wearing the binding member 設 け る provided so as to divide the sheath hole from the inside of the concrete box is closed by filling the binding material after the fastening member is tightened. Fourthly, the gist of the concrete box is that it has end faces that are inclined to the left and right.

  Moreover, the concrete box of the present invention is firstly arranged in series for underground burial, and in the concrete box that receives the thrust of the propulsion jack, the corner corner haunch part of the box has a longitudinal direction of the box. Forming a sheath hole through which the tightening member penetrates, secondly, the pipe material is a steel pipe, and third, the depth from the outer peripheral surface and inner surface of the concrete box Provide a sheath hole at a position where the diameter is uniform, fourth, expand the sheath hole in a tapered shape toward both ends, and fifth, provide the sheath hole to be divided from the inside of the concrete box The gist of the present invention is to provide a binder inlet on the upper surface or side surface of the box that communicates with the boxing for wearing the binding member 、, and sixthly, the concrete box has an end face that is inclined to the left and right.

  Although the sheath hole usually has play due to filling of the tightening member with the grout material, etc., according to the present invention, the sheath hole through which the tightening member passes is almost the same as the tightening member. By fixing and arranging the pipe material with the inner diameter of the diameter, and inserting and tightening the tightening member to the tube material, the play between the tightening member and the sheath hole is reduced, and the tightening member moves the concrete box on the joining surface. Since it is not allowed, it is possible to prevent displacement at the joint surface between the concrete boxes.

  In other words, this is due to the fastening member such as a PC steel bar that has been conventionally used for the purpose of preventing the opening of the connecting box end face by the eccentric propulsion thrust at the time of propulsion of the open shield machine or the integration of the entire laid box. It is intended to be able to apply the vertical tightening and tightening of the concrete box to prevent the horizontal displacement of the joint end face of the box. Since this only closes the gap between the conventional binding member and the sheath hole, it can be easily realized without requiring a large design change.

  In addition, since the binding member is a unit that is integrally tightened and integrated with the concrete box embedded in the column, the binding member extends integrally over the entire column direction of the concrete box and It is thick enough to withstand the force applied to the joint end face in the vertical and horizontal directions, and it can be more reliably displaced than the thin and short pins used only at the joint of the concrete box. Can withstand the force of waking up.

  Therefore, even when the thrust is applied to the joint end face of the concrete box in a non-uniform manner such as curve construction, it is possible to reliably prevent the gap between the concrete boxes.

  In addition, since the sheath hole is reinforced by the tube material by inserting the tube material into the sheath hole provided in the concrete box, even if the fastening member penetrating the sheath hole is used for preventing the slippage of the concrete box, It is possible to prevent the concrete box from being damaged due to a lack of a contact portion with the binding member.

  According to the second aspect of the present invention, by using a steel pipe as the pipe material, the strength of the pipe material into which the fastening member for which the steel material is generally used is inserted is shifted in the box which is added to the concrete box joint surface. It is possible to sufficiently withstand the force to be generated. In other words, the steel tube material with sufficient strength opposes the force that causes the concrete boxes to shift, while protecting the sheath hole more reliably, and the concrete box due to chipping near the sheath hole. Can prevent damage.

  According to the third aspect of the present invention, after the fastening member is fastened, the box opening for wearing the fastening member す る which divides the sheath hole from the internal space of the concrete box is filled with the solidifying material and closed. Thus, the binding member is integrally fixed to the concrete box body at the box-opening portion, and there is no play between the binding member and the concrete box, and the gap between the concrete boxes can be more reliably prevented by the binding member. .

  According to the fourth aspect of the present invention, by using a concrete box having an end face that is inclined to the left and right, the end face of the box is made to follow the direction of receiving the thrust of the propulsion jack, and the thrust is applied to the entire end face of the concrete box. Can be applied evenly, and the bias of the force applied to the box end face can be eliminated to prevent the concrete box from shifting more reliably.

  According to the fifth aspect of the present invention, since the sheath material is formed by penetrating the tube material in the corner-corner haunch portion of the housing in the front-rear direction of the housing, the sheath hole is reinforced by the tubular material, Even if the member is used to stop the displacement of the box, it can withstand the load.

  By inserting a tightening member having the same diameter as the inner diameter of the sheath hole into the reinforced sheath hole, play between the tightening member and the sheath hole is reduced, and the concrete box moves on the joint surface. In the same manner as in the first aspect of the present invention, even when the thrust is applied non-uniformly to the joint end face of the concrete box, such as in the case of curved construction, Misalignment can be reliably prevented.

  And since the sheath hole is reinforced by arranging the pipe material as the sheath hole provided in the concrete box, even if the fastening member penetrating the sheath hole is used for preventing the displacement of the concrete box, the fastening member It is possible to prevent the concrete box from being damaged due to the lack of the contact portion.

  Moreover, according to this invention of Claim 6, like this invention of Claim 2, the strength of the pipe material which inserts the fastening member generally used with steel material is used by using a steel pipe as a pipe material. In addition, it is possible to sufficiently withstand the force to cause a displacement of the box applied to the joint surface of the concrete box. In other words, the steel tube material with sufficient strength opposes the force that causes the concrete boxes to shift, while protecting the sheath hole more reliably, and the concrete box due to chipping near the sheath hole. Can prevent damage.

  According to the seventh aspect of the present invention, since the sheath hole is provided at a position where the depth from the outer peripheral surface and the inner surface of the concrete box is uniform, the joint end face of the concrete box is displaced. Even if a force to be applied is applied and a load is applied to the concrete around the tightening member opposite to this, the concrete around the tightening member has no extremely thin portion, so there is no particularly low strength portion, Even when the binding member is used as a stopper between the concrete boxes, the concrete box is not damaged due to chipping in the concrete around the binding member.

  According to the eighth aspect of the present invention, since the end portion of the sheath hole is formed in a taper shape in advance, when the tightening member is used as a displacement stopper between the concrete boxes, the sheath hole is positioned near the joint portion of the concrete box. Thus, it is possible to prevent the chipping of concrete at the end of the sheath hole that is particularly likely to be loaded.

  According to the ninth aspect of the present invention, the solid material inlet is provided on the upper surface or the side surface of the box so as to communicate with the box opening for wearing the binding member 設 け る provided so as to divide the sheath hole from the inside of the concrete box. Since it did in this way, by pouring a solidification material from this solidification material inflow port after installation of a concrete box, it can be easily filled with a solidification material and obstruct | occluded in boxing of the binding member 碇. As a result, the binding member is integrally fixed to the concrete box body at the box-opening portion, and there is no play between the binding member and the concrete box, and the binding member can more reliably prevent the gap between the concrete boxes. it can.

  According to the tenth aspect of the present invention, since the concrete box has the end face inclined to the left and right, the end face of the concrete box can be made to follow the direction of receiving the thrust of the propulsion jack. Thereby, since the thrust of the propulsion jack is applied evenly to the entire end face of the concrete box, it is possible to eliminate the bias of the force applied to the end face of the box and prevent the concrete box from shifting more reliably. .

  As described above, the concrete box connecting method and the concrete box according to the present invention reliably prevent misalignment between the concrete boxes when the thrust is applied unevenly to the joint end face of the concrete box, such as curved construction. it can.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal front view of a corner corner haunch portion of a concrete box used in the first embodiment of the method for connecting concrete boxes of the present invention. Since the connecting method of the concrete box and the open shield method using the concrete box of the present invention are the same as those in the conventional example, detailed description thereof is omitted here. Moreover, the same code | symbol is attached | subjected about the component same as the said prior art example.

  As shown in FIG. 1, a concrete box 40 made of reinforced concrete is composed of left and right side plates and upper and lower floorboards as in the above-described conventional example. A sheath hole 12 is provided in the part. In the figure, reference numeral 40a is a reinforcing bar, and 17 is a punching box remover used when connecting and fastening the PC steel bar 21 as a fastening member.

  In the sheath hole 12, a carbon steel pipe for piping (hereinafter referred to as a gas pipe) 12a called a gas pipe is inserted and arranged. The gas pipe 12a has, for example, a thickness of 3.5 mm, an outer diameter of 48.6 mm, and an inner diameter of 41.6 mm.

  As in the conventional example, in the process of digging the open shield machine in the ground and suspending the concrete box 40 one after another, and embedding the concrete box 40 in a column, the concrete box 40 is placed on the tail part of the open shield machine. After hanging and placing, a PC steel rod 21 having a diameter of 40 mm is inserted into the gas pipe 12a as a fastening member, temporarily tightened to further dig an open shield machine, and then the PC steel rod 21 is attached by a fastening jack. Tighten tightly.

  In this state, there is only a small gap between the PC steel bar 21 and the gas pipe 12a, and there is little play. Then, even if the concrete shield 40 is used as a reaction force and an open shield machine is dug to carry out curve construction. The PC steel bar 21 does not allow the concrete box 40 to move on the joint surface. Therefore, the gap between the concrete boxes 40 can be reliably prevented.

  Further, by reinforcing the sheath hole 12 with the gas pipe 12a, the sheath hole 12 can withstand a force that causes the concrete box 40 to be displaced, and the displacement of the joint surface of the concrete box 40 is prevented. At the same time, it is possible to prevent the concrete box 40 from being damaged due to, for example, the sheath hole 12 being chipped due to a load applied as a driving reaction force from the open shield machine.

In the present embodiment, various sizes can be used as the size of the gas pipe 12a and the PC steel rod 21 used as long as the gap between the gas pipe 12a and the PC steel rod 21 is small. . For example, the correspondence between applicable gas pipe 12a and PC steel rod 12 is shown in the following table.

  Further, when the outer diameter of the gas pipe 12a and the diameter of the sheath hole 12 are substantially the same diameter, even if the gas pipe 12a is inserted into the sheath hole 12, the play of the gas pipe 12a with respect to the sheath hole 12 is little. However, when there is an opening between the outer diameter of the gas pipe 12a and the diameter of the sheath hole 12, the grout is injected into the gap between the gas pipe 12a and the sheath hole 12 by a method such as injecting grout. The gas pipe 12a can be fixed.

  As described above, even if the conventional concrete box is used as it is, by inserting a pipe material such as the gas pipe 12a into the sheath hole 12, the gap between the concrete boxes can be surely prevented. However, the concrete box can also be configured as follows.

  FIG. 2 shows a first embodiment of the concrete box of the present invention. As shown in FIG. 2, the concrete box 41 of the present invention is made of reinforced concrete, and its basic structure is composed of a left side plate 4a, a right side plate 4b, an upper floor plate 4c, and a lower floor plate 4d, as in the conventional example. The front and rear surfaces are opened as openings 10.

  The corner of the concrete box 41 has a large concrete thickness in order to increase the strength of the concrete box 41, and the PC steel bar 21 (not shown in FIG. 2) is used as a fastening member in the corner corner haunch part of the end face 4e. A sheath hole 12 is provided through which (shown) penetrates.

  In addition, the position where the sheath hole 12 is provided is set so that the depth from each surface of the concrete box 41 is uniform. For example, taking the case of the sheath hole 12 located in the lower right in the figure, the distance L1 from the bottom surface of the concrete box 41, the distance L2 from the side surface, and the distance L3 from the inner surface are uniform. It should be provided in the position. Thus, all the sheath holes 12 are provided at positions where the depth from each surface of the concrete box 41 is uniform.

  As shown also in FIG. 3 which is a longitudinal side view of the concrete box 41, the sheath hole 12 is formed by disposing a gas pipe 12a, and both ends thereof are tapered portions 12b whose diameter increases toward the end. Yes. In the figure, reference numeral 17 denotes a box for wearing a scissors used when connecting and fastening a PC steel rod (not shown in FIG. 3) as a fastening member.

  The method of using the concrete box 41 is the same as that of the above embodiment. In the process of digging up the open shield machine in the ground and suspending the concrete box 41 in sequence, After the concrete box 41 is suspended and placed on the tail of the machine, a 40 mm diameter PC steel rod is inserted into the sheath hole 12 as a fastening member and temporarily tightened to further advance the open shield machine The PC steel bar is tightened vertically with a binding jack.

  In this state, there is only a small gap between the PC steel rod and the sheath hole 12 and there is little play. Then, even if the concrete shield 41 is used as a reaction force and the open shield machine is dug to perform the curve construction, The PC steel bar does not allow the concrete box 41 to move on the joint surface. Therefore, the gap between the concrete boxes 41 can be reliably prevented.

  Further, by reinforcing the sheath hole 12 with the gas pipe 12a, the sheath hole 12 can withstand a force that causes the concrete box 41 to be displaced, and prevents the joint surface of the concrete box 41 from being displaced. At the same time, it is possible to prevent the concrete box 41 from being damaged due to, for example, the sheath hole 12 being lost due to a load applied as a driving reaction force from the open shield machine.

  Although there is only a small gap between the sheath hole 12 and the PC steel rod, since the end of the sheath hole 12 is a tapered portion 12b, the PC steel rod can be easily inserted into the sheath hole 12, It is also possible to use the sheath hole 12 and the PC steel bar as a guide when the concrete box 41 is installed.

  Further, when an external force is applied to cause the gap between the concrete boxes 41 at the joint end of the concrete box 41, a large load is applied to the end of the sheath hole 12, but the end of the sheath hole 12 is By setting it as the taper part 12b, the chipping of the concrete in the sheath hole 12 edge part can be prevented.

  FIG. 4 shows a second embodiment of the concrete box of the present invention. The basic structure of the concrete box 42 of the present embodiment is the same as that of the first embodiment, but the consolidating material inlet 22 that communicates with the paddle box 17 located on the upper stage is provided on the upper surface of the concrete box 42. Open to form.

  The basic method of using the concrete box 42 is the same as that of the first embodiment, and the open shield machine is dug in the ground and the concrete box 42 is sequentially suspended to embed the concrete boxes 42 in tandem. In the process, after the concrete box 42 is suspended and placed on the tail part of the open shield machine, a PC steel rod 21 is inserted into the sheath hole 12 as a fastening member and temporarily tightened to further dig the open shield machine. Then, the PC steel bar 21 is fastened and fastened with a tight jack.

  Thereafter, the inside of the box opener 17 worn with the binding member heel is consolidated by the following procedure. First, one end of the separator 16 is joined to the PC steel rod 21 located in the box opening 17 inside the concrete box 42 by welding or a joining member, and the other end is connected to the plastic cone 16a for plywood. A panel 14 having a through hole for a foot 15a is used to close the opening inside the concrete box 42 of the boxing box 17 and the shaft foot 15a of the foam tie 15 is inserted into the plastic cone 16a to tighten the foam tie 15. To fix.

  Thus, after closing the opening inside the concrete box 42 of the box box 17, non-shrink mortar is injected from the consolidated material inlet 22, and the box box 17 is filled with non-shrink mortar and consolidated. To do. Thereafter, the control panel 14 and the foam tie 15 are removed.

  As a result, the PC steel bar 21 is integrally fixed to the concrete box 42 main body in the box opener 17, and there is no play between the PC steel bar 21 and the concrete box 42 in the box opener 17 part, which is the same as in the previous embodiment. In addition to the above action, the PC steel rod 21 can more reliably prevent the concrete boxes 42 from being displaced.

  The consolidated material inlet 22 may be formed so as to communicate with the box opening 17 from the side surface of the concrete box 42. Further, the binder inlet 22 may be formed in the lower box opening 17 from the side of the concrete box 42, but the lower box opening 17 is directly fixed from the opening inside the concrete box 42. Since the binder can be poured, it is not particularly necessary to form the solid binder inlet 22.

Further, in both the first embodiment and the second embodiment of the concrete box of the present invention, the sizes of the gas pipe 12a and the PC steel bar 21 used as the sheath hole 12 are the gas pipe 12a and the PC steel bar. Various sizes can be used as long as the gap with 21 is small. For example, the correspondence between applicable gas pipe 12a and PC steel rod 12 is shown in the following table.

  Moreover, as 3rd Embodiment of the concrete box of this invention, as shown with a dashed-dotted line in FIG. 2, you may make it the concrete box 41 have the end surface 4e inclined to right and left. Although not shown in the figure, when using a linear binding member such as a PC steel rod 21, the sheath holes 12 of the adjacent concrete boxes 41 are linear on the joint surface of the concrete box 41. The sheath hole 12 is formed so as to be.

  Furthermore, when using a PC steel wire instead of the PC steel rod 21 as the fastening member, the sheath hole 12 is provided with a large taper portion 12b of the sheath hole 12 or the sheath hole 12 smoothly continues on the joint surface of the concrete box 41. As such, the sheath hole 12 may be curved.

  In the case of using the PC steel bar 21 as the fastening member, the connecting method of the concrete box 41 like this is similar to the first embodiment of the connecting method of the concrete box of the present invention. After inserting the PC steel bar 21 between them and propelling the open shield machine 1, it is fastened by the tight jack 21 c at the bag wearing box remover 17.

  Moreover, when using a PC steel wire as a fastening member, a PC steel wire is inserted into the sheath hole 12, a grout material is injected into the sheath hole 12, and then the PC steel wire is tensioned to harden the grout material. Later, the tension of the PC steel wire is released.

  Thereby, the direction of the end face 4e follows the construction curve, and the reaction force when propelled by the open shield machine is evenly applied to the entire end face 4e. Therefore, the concrete box 41 is tightened by the fastening force of the fastening member. In addition to preventing the displacement, the deviation of the force applied to the end face 4e can be eliminated, and the concrete box 42 can be more reliably prevented from shifting.

  Further, when the PC steel bar 21 is used as the fastening member, the sheath hole 12 is formed so as to be linear on the joint surface of the concrete box 41, and when the PC steel wire is used as the fastening member. The tightening force of the tightening member can be increased by providing a large tapered portion 12b of the sheath hole 12 or by curving the sheath hole 12 so that the sheath hole 12 continues smoothly on the joint surface of the concrete box 41. It is sufficiently exerted and the effect of preventing the concrete box 41 from shifting can be sufficiently obtained.

It is a vertical front view of the corner corner haunch part of the concrete box used for 1st Embodiment of the connection method of the concrete box of this invention. It is a whole perspective view which shows 1st Embodiment of the concrete box of this invention. It is a vertical side view which shows the principal part of 1st Embodiment of the concrete box of this invention. It is a vertical front view which shows the principal part of 2nd Embodiment of the concrete box of this invention. It is a vertical side view which shows the outline of an open shield construction method. It is a perspective view of the conventional concrete box. It is a vertical side view which shows the 1st step of the vertical fastening tightness of a concrete box. It is a vertical side view which expands and shows the front-end | tip of the tightly bound PC steel bar. It is a vertical side view which shows the 2nd step of the vertical fastening tightness of a concrete box. It is a vertical side view which shows the final stage of the vertical fastening of a concrete box. It is a vertical side view which shows the fastening of the fastening member by a binding jack. It is a top view which shows a mode that the force which produces a shift | offset | difference acts on the junction part of a concrete box by a new open shield construction method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Open shield machine 1a Side wall board 1b Bottom board 1c Tail part 2 Propulsion jack 3 Bulkhead 4 Concrete box 4a Left side board 4b Right side board 4c Upper floor board 4d Lower floor board 4e End surface part 5 Backfilling soil 6 Grout material 7 Height adjustment material 8 Press Bar 9 Excavator 10 Opening 11 Cutting edge 12 Sheath hole 12a Gas pipe 12b Tapered part 13 Insertion hole 14 Panel 15 Foam tie 16 Separator 16a Plastic cone 17 Unboxing box 21 PC steel bar 21a Bearing plate 21b Nut 21c Tightening jack 21d Coupler 21e Connecting rod 22 Consolidating material inlet 40 Concrete box 40a Reinforcing bar 41, 42 Concrete box

Claims (10)

  In a concrete box connection method in which concrete boxes that are placed in series in series and receive thrust from a propulsion jack are fastened by a fastening member such as a PC steel rod, they are tightly connected to a sheath hole through which the fastening member passes. A connecting method for a concrete box, wherein a pipe material having an inner diameter substantially the same as a member is fixedly arranged, and a fastening member is inserted into the pipe material and fastened.   The method for connecting concrete boxes according to claim 1, wherein a steel pipe is used as the pipe material.   3. The concrete box according to claim 1 or 2, wherein the box opening for wearing the binding member 碇 provided so as to divide the sheath hole from the inside of the concrete box is closed by filling with a solidifying material after the fastening of the binding member. Connection method.   The method for connecting concrete boxes according to any one of claims 1 to 3, wherein the concrete box has an end face inclined to the left and right.   In a concrete box that is sequentially arranged in tandem for underground use and receives the thrust of a propulsion jack, by placing the pipe material in the corner corner haunch part of the box in the longitudinal direction of the box, the binding member is A concrete box characterized in that a sheath hole is formed therethrough.   The concrete box according to claim 5, wherein the pipe material is a steel pipe.   The concrete box according to claim 5 or 6, wherein a sheath hole is provided at a position where the depth from the outer peripheral surface and the inner surface of the concrete box is uniform.   The concrete box according to any one of claims 5 to 7, wherein the diameter of the sheath hole is increased in a tapered shape toward both ends.   9. A solid material inlet provided in a top surface or a side surface of the box, wherein a solid material inlet that communicates with a box opening for wearing a binding member is provided so as to divide the sheath hole from the inside of the concrete box. The concrete box described. The concrete box according to any one of claims 5 to 9, wherein the concrete box has an end face inclined to the left and right.

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