JP2021161634A - Extracting and removing method of joint part formation plate member - Google Patents

Abstract

To provide an extracting and removing method of a joint part formation plate member that obtains a support reaction for extracting a joint part formation plate member in a stable state with a simple configuration and efficiently removes the joint part formation plate member.SOLUTION: A joint part formation plate member 15 includes an extracting engagement portion 15a that engages extracting edge cutting means 20 to an inner projection holding portion 15B. The extracting edge cutting means 20 obtains a support reaction from a divisional framework main body portion 3A in a state of engaging the extracting engagement portion 15a to be displaced in, for example, a rotational direction R, and generates a force in a direction Z in which the joint part formation plate member 15 is extracted to an inside of the divisional framework main body portion 3A. As a result, a join part formation portion 15A of the joint part formation plate member 15 is cut from peripheral hardened concrete that adheres to this, and after that, the joint part formation plate member 15 is extracted toward the inside of the divisional framework main body portion 3A and removed.SELECTED DRAWING: Figure 7

Description

The present invention relates to a method for pulling out and removing a joint portion forming plate member, and in particular, a joint portion forming plate member for pulling out and removing a joint portion forming plate member for forming an induced joint in tunnel lining concrete. Regarding the method of pulling out and removing.

For example, in a tunnel construction method such as a mountain tunnel construction method, a construction method using a tunnel lining formwork called a centre as a method for forming a tunnel lining concrete constructed by covering the ground on the inner peripheral surface of an excavated tunnel. Is generally adopted (see, for example, Patent Document 1 and Patent Document 2). As shown in FIG. 10, for example, the tunnel lining mold 50 is installed from the side wall portion 55 of the tunnel 53 to the upper part along the inner peripheral surface of the tunnel 53 having a shape including an arch-shaped portion 52 such as a horseshoe shape. The lining space 71 between the installed tunnel lining mold 50 and the ground covered by the sprayed concrete 54 on the inner peripheral surface of the tunnel 53 is preferably reinforced concrete. By setting and hardening, the tunnel lining concrete is formed so as to be continuous with the concrete of the invert portion 51 at the bottom of the tunnel.

Further, as the tunnel lining formwork 50, for example, in addition to an assembly type tunnel lining formwork called a ball centre, a mobile tunnel lining formwork called a slide centre is known, and the tunnel 53. As the excavation work progresses, for example, while re-installing the tunnel lining formwork 50 at predetermined construction spans of about 10.5 m, the tunnel lining mold is used from the rear to the front in the excavation direction of the tunnel 53. The lining concrete on the side and the upper part of the tunnel 53 is sequentially cast and formed by using the frame 50.

Then, in order to place the lining concrete on the side and the upper part of the tunnel using the tunnel lining formwork 50, for example, as shown in FIGS. 11A to 11D, the installed tunnel lining is used. As a height region in which concrete can be cast from the inspection window 56 provided in the form 50, for example, the region from the side wall portion 55 of the tunnel 53 to the shoulder portion of the arch-shaped portion 52 is passed through the inspection window 56. The concrete 57 is supplied, and the vibrator 58 is inserted through the inspection window 56, and the concrete 57 is placed while compacting the supplied concrete 57 (see FIGS. 11A to 11C). After that, as a height region that is difficult to compact by the vibrator 58 while supplying concrete 57 from the inspection window 56, the tunnel is provided for the region of the crown portion (crown portion) 59 (see FIG. 10) of the tunnel 53. A pattern is adopted in which concrete 57 is press-fitted and driven by a blow-up method from a blow-up inlet 70 provided at the top end of the lining form 50 to form the concrete 57 of the crown 59 (FIG. 11 (d)). )reference).

More specifically, after installing the tunnel lining formwork 50 at a predetermined position, for example, from the lower part of the side wall portion 55, concrete 57 is poured through the lower inspection window 56 and compacted using the vibrator 58. (See FIG. 11A), and a step of compacting the concrete 57 with the vibrator 58 while pouring the concrete 57 toward the arch-shaped portion 52 above the side wall portion 55 through the inspection window 56 in the middle stage (FIG. 11 (a)). b)) and the step of compacting using the vibrator 58 while pouring concrete 57 through the upper inspection window 56 and, if necessary, the blow-up inlet 70 to the front of the crown portion 59 of the arch-shaped portion 52. (See FIG. 11 (c)) and the step of press-fitting concrete 57 from the existing lining concrete 72 side portion of the crown portion 59 through the blow-up inlet 70 by a blow-up method and filling the concrete up to the end form 73. (See FIG. 11 (d)), the lining concrete will be placed.

Japanese Unexamined Patent Publication No. 2001-280094 Japanese Unexamined Patent Publication No. 2003-262206 Japanese Unexamined Patent Publication No. 2015-67749

On the other hand, in recent tunnel construction methods, the progress of the process for forming lining concrete, from concrete placement to curing and demolding of the tunnel lining formwork, is due to the improvement of excavation technology. It is not possible to keep up with the progress of the process of excavating concrete. Therefore, as a technique for accelerating the progress of the process of forming the lining concrete, a plurality of concrete pumps are used (see, for example, Patent Document 3), or a commonly used tunnel covering having a construction extension of about 10.5 m is used. By using a long-span tunnel lining formwork having a construction extension of about 18 m to 22 m, instead of the construction formwork, and extending the construction span of the tunnel lining concrete performed in one cycle, the construction period Is being considered for shortening.

Further, when the construction span of the tunnel lining concrete performed in one cycle is extended by using a long-span tunnel lining formwork having a construction extension of preferably about 18 m to 22 m, the intermediate portion of the construction span is formed. Since cracks due to dry shrinkage and temperature shrinkage are likely to occur, inducing cracks due to dry shrinkage and temperature shrinkage in the middle part, especially when forming tunnel lining concrete with a long construction span. It is desirable to provide joints. For this reason, the applicant of the present application, as a method of providing an induced joint in the intermediate portion of the tunnel lining concrete, for example, in Japanese Patent Application No. 2018-147241, projects from the formwork surface of the tunnel lining formwork to the lining space. A plurality of joint plate members are arranged in a row in the circumferential direction and attached so that they can be pulled out. When the concrete placed in the lining space is hardened, the joint forming plate members are lining. It discloses a method of forming an induced joint by pulling it out of space.

On the other hand, in the work of pulling out the joint forming plate member from the hardened tunnel lining concrete cast in the lining space, the joint forming portion of the joint forming plate member becomes the hardened surrounding tunnel lining concrete. Since it is firmly adhered, a large pulling force is required especially when first cutting off the adhesion between the joint forming portion of the joint forming plate member and the hardened surrounding tunnel lining concrete, so that the worker It is difficult to pull out the joint portion forming plate member only by the manual work of.

For this reason, the work of pulling out the joint plate member using various jigs for pulling out, for example, a lever block (registered trademark), has been performed, but the inside of the formwork body of the formwork for tunnel lining has been performed. It may be difficult to obtain a supporting reaction force when pulling out the joint forming plate member from various facilities or temporary members installed in the space, and depending on the location where the joint forming plate member is provided. , It takes a lot of time and effort to provide a mechanism for stably obtaining a supporting reaction force.

INDUSTRIAL APPLICABILITY According to the present invention, it takes a lot of time and effort to easily obtain a supporting reaction force when pulling out a joint forming plate member inside a tunnel lining formwork in a stable state by a simple configuration. It is an object of the present invention to provide a method for pulling out and removing a joint portion forming plate member which can efficiently pull out and remove each of a plurality of joint portion forming plate members which are continuously installed in the circumferential direction. do.

The present invention induces the tunnel lining concrete to be constructed, which is pullably attached to the intermediate portion in the axial direction of the tunnel lining mold installed when constructing the tunnel lining concrete in the mountain tunnel construction method. This is a method for pulling out and removing the joint portion forming plate member for pulling out and removing the joint portion forming plate member for forming the joint after the cast concrete has hardened, and is a method for pulling out and removing the joint portion forming mold. Is provided with a gantry portion that can move in the excavation direction of the tunnel and a mold body portion that is supported by the gantry portion and forms a lining space between the inner wall surface of the tunnel. Is composed of a plurality of divided form main bodies divided in the excavation direction of the tunnel, and a slit-shaped gap extends over the entire circumference between the adjacent ends of these divided form main bodies. A plurality of the joint portion forming plate members are inserted into the slit-shaped gaps that are continuously formed, and the inserted joint portion forming plate members form joint portions on the outer peripheral portion side. With the portion protruding into the lining space, the inner protruding grip portion on the inner peripheral portion side is fixed to the split mold main body portion, and is continuously arranged and attached in the circumferential direction, and the joint portion is attached. The forming plate member includes a pull-out engaging portion for engaging the pull-out edge cutting means with the inner protruding grip portion, and the pull-out edge cutting means is a split type in a state of being engaged with the pull-out engagement portion. By obtaining a supporting reaction force from the frame main body and displacement, a force is generated in the direction of pulling out the joint forming plate member inside the split mold main body, and the joint forming plate member is said to be said. The joint portion forming portion is trimmed from the surrounding hardened concrete that is in close contact with the joint portion forming portion, and then the joint portion forming plate member is pulled out inside the divided mold main body portion to be removed. By providing a method for pulling out and removing the above-mentioned purpose.

The method for pulling out and removing the joint portion forming plate member of the present invention comprises an action point protrusion in which the pull-out engaging portion is fixed by vertically projecting from the inner protruding grip portion of the joint portion forming plate member. The pull-out edge cutting means is composed of a rod-shaped member having a tip portion inserted between the action point protrusion and the split formwork main body portion, and the rod-shaped member into which the tip portion is inserted is displaced in the rotational direction. According to this principle, it is preferable that a force is generated in the direction of pulling out the joint portion forming plate member inside the divided formwork main body portion.

Further, in the method of pulling out and removing the joint portion forming plate member of the present invention, it is preferable that the action point protrusion is detachably fixed to the inner protruding grip portion of the joint portion forming plate member.

Further, in the method of pulling out and removing the joint portion forming plate member of the present invention, a pair of the action point protrusions are arranged on both side portions of the joint portion forming plate member with the circumferential center line in the inner protruding grip portion. The tip portions of the two rod-shaped members are inserted between the respective action point protrusions and the split formwork main body portion from the outside and displaced in the rotational direction. According to this principle, it is preferable that a force is generated in the direction of pulling out the joint portion forming plate member inside the split formwork main body portion.

Furthermore, in the method of pulling out and removing the joint portion forming plate member of the present invention, the pull-out engaging portion is fixed by projecting to both sides of the inner protruding grip portion of the joint portion forming plate member. The pull-out edge cutting means is screwed into the female screw holes of each of the pair of reaction force plates and rotates to move forward and backward toward the split formwork main body. It is composed of a pair of bolt members that are displaced in such a manner, and the joint portion forming plate member is displaced so that the tip portion presses the split formwork main body by rotating these bolt members. It is preferable that a force in the pulling direction is generated inside the portion.

Further, in the method of pulling out and removing the joint portion forming plate member of the present invention, the pull-out engaging portion comprises a plate-side wedge engaging hole formed in the inner protruding grip portion of the joint portion forming plate member. The pull-out edge cutting means is fixed to the split mold main body in a state of being arranged along the inner protruding grip portion of the joint portion forming plate member, and is provided with a reaction force side wedge engaging hole. It is composed of a reaction force plate, an overlapping plate-side wedge engagement hole, and a wedge member driven into the reaction force-side wedge engagement, and the reaction force-side wedge engagement hole is formed with respect to the plate-side wedge engagement hole. By driving the wedge member in a state of being displaced inward in the radial direction of the split mold main body portion, the joint portion forming plate member is displaced relative to the reaction force plate to form the joint portion. It is preferable that a force is generated in the direction of pulling out the plate member inside the split mold main body.

According to the method for pulling out and removing the joint portion forming plate member of the present invention, the supporting reaction force when pulling out the joint portion forming plate member inside the tunnel lining formwork can be easily performed in a stable state by a simple configuration. It is possible to efficiently pull out and remove each of the plurality of joint portion forming plate members that are continuously installed in the circumferential direction without requiring a lot of trouble.

In the tunnel lining formwork, it is a substantially cross-sectional view of a state in which a plurality of joint portion forming plate members are arranged in succession in the circumferential direction of the divided formwork body portion by projecting the joint portion forming portion into the lining space. .. It is a schematic vertical sectional view explaining the tunnel lining formwork to which the plate member for forming a joint part is attached. It is a schematic plan view explaining the tunnel lining formwork to which the plate member for forming a joint part is attached. FIG. 5 is an enlarged cross-sectional view taken along the line AA of FIG. 1 in the A'part of FIG. 2 for explaining a mounting structure for mounting the joint portion forming plate member to the tunnel lining formwork. It is a front view of the plate member for forming a joint portion. It is a side view (the view in the arrow view B direction of FIG. 5) of the plate member for forming a joint part. (A) and (b) are explanatory views of the method of pulling out and removing the joint portion forming plate member which concerns on the preferable 1st Embodiment of this invention. (A) and (b) are explanatory views of the method of pulling out and removing the joint portion forming plate member which concerns on the preferable 2nd Embodiment of this invention. (A) and (c) are explanatory views of the method of pulling out and removing the joint portion forming plate member according to the preferred third embodiment of the present invention, (b) is an enlarged view of part B of (a), and (d) is. It is the C part enlarged view of (c). It is a schematic cross-sectional view explaining the state which installed the tunnel lining formwork along the inner peripheral surface of a tunnel in the conventional tunnel lining concrete placing method. (A) to (d) are schematic side views showing a part as a cross-sectional view explaining the work procedure of the conventional tunnel lining concrete placing method.

The method of pulling out and removing the joint portion forming plate member according to the preferred first embodiment of the present invention (see FIGS. 7A and 7B) is a tunnel lining concrete 4 covering the inner wall surface of the tunnel in the mountain tunnel construction method. (See FIGS. 2 and 3) is a joint for forming an induced joint in the tunnel lining concrete 4 to be constructed when the tunnel lining mold 1 (see FIGS. 1 to 3) is used for construction. The part-forming plate member 15 (see FIG. 4) is adopted as a method for pulling out and removing the part-forming plate member 15 (see FIG. 4) from the tunnel lining concrete 4 after the concrete placed in the lining space S has hardened. In the first embodiment, the tunnel lining concrete 4 constructed by covering the inner peripheral surface of the excavated tunnel T is 10.5 m, which is generally used as a tunnel lining mold 1 called a centre. Instead of the one having a construction extension of about 18 m to 22 m, it is formed by using a long-span tunnel lining mold 1 having a construction extension of about 18 m to 22 m, and the joint portion forming plate member 15 is formed. Will be installed as a member for forming an induced joint that induces cracks due to drying shrinkage and temperature shrinkage in the middle portion of the construction span of the tunnel lining concrete 4 to be constructed.

That is, in the recent mountain tunnel construction method, the progress of the process for forming the lining concrete 4 from the placing of concrete to the curing and the demolding of the tunnel lining mold 1 is made by improving the excavation technology. In this first embodiment, a tunnel having an extension of about 10.5 m, which is generally used, is often used because it cannot keep up with the progress of the process of excavating the face surface of T and it is often not constructed efficiently. Instead of the lining mold, preferably a long-span tunnel lining mold 1 having a construction extension of 10.5 m or more, for example, a long-span tunnel lining mold having an extension of about 18 to 22 m. By using 1, the construction span of the lining concrete 4 performed in one cycle is increased, and by using two concrete pumps 30, concrete 12 is cast from two systems of pumping pipes 31 at the same time. It is possible to shorten the working time when placing the 12 and accelerate the progress of the process for forming the lining concrete 4.

Further, in the first embodiment, if the extension of the construction span of one cycle of the lining concrete 4 is increased by using the long-span tunnel lining formwork 1, only the boundary portion of the adjacent construction spans can be used. , Cracks due to drying shrinkage and temperature shrinkage of concrete cannot be sufficiently absorbed, and cracks are likely to occur in the middle part of the construction span. Therefore, a joint portion forming plate member 15 for forming an induced joint that induces cracks due to drying shrinkage or temperature shrinkage is inserted into the slit-shaped gap δ in the middle portion of the construction span (see FIG. 4). In a state where the joint portion forming portion 15A is projected into the lining space S, the joint portion forming portion 15A is continuously arranged in the circumferential direction, and a pair of split formwork main bodies constituting the formwork main body portion 3 of the tunnel lining formwork 1 is formed. It is fixedly attached to the ends of the portions 3A and 3B. In the method of pulling out and removing the joint portion forming plate member of the first embodiment (see FIGS. 7A and 7B), after the concrete placed in the lining space S is hardened, the joints are formed from the hardened concrete. When the part-forming plate member 15 is pulled out to form an induced joint, a supporting reaction force can be easily obtained in a stable state, and the joints are continuously installed in the circumferential direction without much labor. It is adopted as a method for efficiently pulling out and removing each of the plurality of joint portion forming plate members 15.

Then, the method of pulling out and removing the joint portion forming plate member of the first embodiment is a tunnel lining mold installed when constructing the tunnel lining concrete covering the inner wall surface of the tunnel in the mountain tunnel construction method. A joint forming plate member 15 (FIG. 5, FIG. 3) for forming an induced joint in the tunnel lining concrete 4 to be constructed, which is pullably attached to the intermediate portion in the axial direction X of FIGS. 1 to 3). (See FIG. 6) is a pull-out removal method for pulling out and removing the cast concrete after it has hardened (see FIGS. 7 (a) and 7 (b)).

As shown in FIGS. 1 to 3, the tunnel lining formwork 1 is formed between a pedestal portion 2 that can move in the tunnel excavation direction X and an inner wall surface of the tunnel T that is supported by the pedestal portion 2. It includes a formwork main body 3 that forms a lining space S. The formwork main body 3 is composed of a plurality of (a pair in the first embodiment) divided formwork main bodies 3A and 3B divided in the tunnel excavation direction (two divisions in the first embodiment). A slit-shaped gap δ (see FIG. 4) is continuously formed over the entire circumference between the adjacent ends of the divided formwork main bodies 3A and 3B. A plurality of joint portion forming plate members 15 are inserted into the slit-shaped gap δ (see FIG. 1), and the inserted joint portion forming plate member 15 is inserted into the joint portion forming portion 15A on the outer peripheral portion side. With (see FIG. 5) protruding into the lining space S, the inner protruding grip portion 15B on the inner peripheral portion side is preferably fixed to the split formwork main bodies 3A and 3B on both sides with a slit-shaped gap δ sandwiched between them. Then (see FIG. 4), they are continuously arranged and attached in the circumferential direction.

In the method of pulling out and removing the joint portion forming plate member of the first embodiment, as shown in FIGS. 4 to 6, the joint portion forming plate member 15 is attached to the inner protruding grip portion 15B by the pulling edge cutting means 20 (FIG. A pull-out engaging portion 15a for engaging 7 (a) and 7 (b)) is provided, and the pull-out edge cutting means 20 is provided on the pull-out engagement portion 15a as shown in FIGS. 7 (a) and 7 (b). In the engaged state, the support reaction force is obtained from the split formwork main bodies 3A and 3B and displaced in the rotation direction R, for example, so that the joint portion forming plate member 15 is placed inside the split formwork main bodies 3A and 3B. A force in the pulling direction Z is generated to cut the joint forming portion 15A of the joint forming plate member 15 from the surrounding hardened concrete that is in close contact with the joint forming portion 15A. It is designed to be pulled out inside the split formwork main bodies 3A and 3B to be removed.

Further, in the method of pulling out and removing the joint portion forming plate member of the first embodiment, the pull-out engaging portion 15a protrudes vertically from the inner protruding grip portion 15B of the joint portion forming plate member 15 and is fixed. The pull-out edge cutting means 20 is composed of a protrusion 60, and the pull-out edge cutting means 20 is composed of a rod-shaped member 61 having a tip portion 61a inserted between the action point protrusion 60 and the split formwork main bodies 3A and 3B (see FIG. 7A), and the tip portion. The rod-shaped member 61 into which the 61a is inserted is preferably displaced in the rotation direction R centered on the concave support portion 62a at the tip of the erection fulcrum plate 62, so that the joint portion forming plate member 15 is formed by the principle of the lever. A force in the pulling direction Z is generated inside the split formwork main bodies 3A and 3B.

Further, in the method of pulling out and removing the joint portion forming plate member of the first embodiment, the action point protrusion 60 is the circumferential center line C in the inner protruding grip portion 15B of the joint portion forming plate member 15 (see FIG. 5). A pair of the tip portions 61a of the two rod-shaped members 61 are arranged and fixed on both side portions sandwiching the above-mentioned parts, and the tip portions 61a of the two rod-shaped members 61 are placed between the respective action point protrusions 60 and the split formwork main bodies 3A and 3B from the outside. By inserting and displacing each in the rotation direction R (see FIG. 7A) about the concave support portion 62a (see FIG. 4) at the tip of the erection fulcrum plate 62, by the principle of the lever. A force in the direction Z for pulling out the joint portion forming plate member 15 inside the split formwork main bodies 3A and 3B is generated.

In the first embodiment, the tunnel lining formwork 1 to which a plurality of joint portion forming plate members 15 are attached to the intermediate portion becomes a slide center that can move in the extension direction (digging direction) X of the tunnel T. It is a long-span tunnel with an extension of, for example, about 18 to 22 m. The tunnel lining formwork 1 has substantially the same configuration as the tunnel lining formwork described in, for example, Japanese Patent Application Laid-Open No. 2015-67749, except that the formwork 1 has a long span.

That is, as shown in FIGS. 1 to 3, the tunnel lining formwork 1 is connected to and integrated with the gantry portion 2 formed by a plurality of gate-shaped trolleys 2A, which are connected and integrated in the excavation direction X (see FIG. 2) of the tunnel T. , Supported by the gantry 2 by these integrated gate-type carriages 2A, and arranged along the inner peripheral surface of the tunnel T covered by, for example, the primary lining 5 with sprayed concrete (see FIG. 1). ), And the formwork main body 3 forming the formwork surface inside the lining space S is included. The gate-shaped carriage 2A constituting the gantry portion 2 includes a base portion 2a and a support leg portion 2b for supporting the base portion 2a. At the lower end of the support leg portion 2b, a traveling portion 7 capable of traveling along the rail 6 laid on the floor surface of the tunnel T is provided, whereby the tunnel lining formwork 1 is formed in the tunnel T. It is possible to move in the excavation direction X.

The form main body 3 is assembled so as to have a shape along the inner peripheral surface of the tunnel T covered by the primary lining 5, and is spaced from the inner peripheral surface of the tunnel T at a predetermined distance. By being arranged, a lining space S having a predetermined thickness, which is a concrete casting space, is formed. Further, as shown in FIG. 1, the formwork body 3 includes an upper formwork 3a for forming an lining space S above the arch-shaped portion 52 of the tunnel T, and the lower part and both sides of the arch-shaped portion 52. A pair of side formwork 3b for forming the upper lining space S of the side wall portion 55, and a pair of lower end portions for forming the lower lining space S of the lower side wall portion 55 connected to the concrete of the invert portion. It is configured to include the formwork 3c. The upper formwork 3a is supported so as to be able to move up and down in the vertical direction by a plurality of elevating jacks 8 provided on the base portion 2a of the gate type bogie 2A constituting the gantry portion 2. The pair of side formwork 3b is rotatably connected to the lower ends on both sides of the upper formwork 3a via a rotary connecting portion 3d, and the pair of lower end formwork 3c is connected to each side formwork. It is rotatably connected to the lower end of 3b via the lower rotary connecting portion 3e. The side formwork 3b and the lower end formwork 3c are connected to the other ends of the telescopic jacks 9a and 9b whose one end is connected to the gate type carriage 2A, and these telescopic jacks 9a and 9b are expanded and contracted. The side formwork 3b and the lower end formwork 3c can be rotated with respect to the upper formwork 3a and the side formwork 3b.

As a result, the formwork 1 for tunnel lining can expand and contract the elevating jack 8 and the telescopic jacks 9a and 9b so that the formwork main body 3 can be expanded or put together inside the tunnel T. The formwork body 3 can be assembled along the inner peripheral surface of the tunnel T, or the formwork body 3 can be moved in the excavation direction X inside the tunnel T after being removed from the mold.

Further, in the first embodiment, a plurality of press-fitting connection ports 11a and 11b are provided in the upper formwork 3a and the side formwork 3b of the formwork body 3 at intervals in the excavation direction X of the tunnel T, respectively. It is formed in two places (see FIG. 2). At the top end of the upper formwork 3a of the formwork body 3, a plurality of zenith press-fitting connection ports 27 are formed at two locations at intervals in the excavation direction X of the tunnel T. As will be described later, these press-fitting connection ports 11a, 11b, and 27 are used for the purpose of pouring or press-fitting the lining concrete 12 that is pumped through the pressure-feeding pipe 31 into the lining space S. Used.

Then, in the first embodiment, the formwork main body 3 of the tunnel lining formwork 1 is preferably 2 in the excavation direction X (left-right direction of FIGS. 2 and 3) of the tunnel T as described above. It is composed of a pair of divided formwork main bodies 3A and 3B. The pair of split formwork main bodies 3A and 3B are arranged and fixed so that a slit-shaped gap δ (see FIG. 4) having a constant width is formed between these adjacent end faces so as to form over the entire circumference. Has been done. Further, the slit-shaped gap δ formed is supported by the end rib plates 21A and 21B forming the end faces of the pair of split formwork main bodies 3A and 3B, and is intermediate between the respective construction spans (L = 18 m). A plurality of joint portion forming plate members 15 for forming an induced joint in the portion project the joint portion forming portion 15A into the lining space S, and are inserted and arranged so as to be able to be pulled out, over the entire circumference. They are arranged in series (see FIG. 1).

In the first embodiment, at least two places (the first embodiment) in the inner protruding grip portion 15B, which is a portion on the inner peripheral portion side of the joint portion forming plate member 15, in a portion close to the joint portion forming portion 15A. Plate-side pin insertion holes 16a are formed at two locations) in the form (see FIG. 5). In the end rib plates 21A and 21B forming the end faces of the pair of split formwork main bodies 3A and 3B, a joint portion forming portion 15A which is a portion on the outer peripheral portion side of the joint portion forming plate member 15 is provided as a lining space. The end face pin insertion hole 23a is formed at a position corresponding to these plate-side pin insertion holes 16a in a state of projecting to S (see FIG. 4). By inserting the pin member 26 (see FIG. 4) into the matched plate-side pin insertion hole 16a and the end face pin insertion hole 23a, the joint portion forming plate member 15 is transferred to the end rib plates 21A and 21B on both sides. It is fixed and attached while being supported so as to be sandwiched.

Further, in the first embodiment, as shown in FIG. 4, the outer peripheral surfaces of the respective end edge portions of the pair of divided formwork main body portions 3A and 3B, which are preferably located on both sides of the slit-shaped gap δ. The face wood members 22A and 22B, which are erected from the above and preferably have a right-angled triangular or right-angled trapezoidal cross-sectional shape, are preferably in a state of protruding into the lining space S, and preferably each of the divided formwork main bodies 3A and 3B. It is continuously attached to the entire circumference in the circumferential direction of.

In the first embodiment, as shown in FIGS. 5 and 6, the joint portion forming plate member 15 is preferably made of aluminum or steel and has a thickness of, for example, about 6 to 10 mm (in the present embodiment, about 7 mm). It is formed using a metal plate of (thickness). Further, the joint portion forming plate member 15 has, for example, an outer peripheral side portion having a vertical width of about 300 to 600 mm and a horizontal width of about 400 to 700 mm, and an inner circumference arranged so as to face the outer peripheral side side portion. It has a substantially four-sided planar shape having side sides and side sides on both the left and right sides. The joint portion forming plate member 15 has a joint portion forming portion 15A in which a portion on the outer peripheral side side portion is arranged so as to project from the formwork surface into the lining space S, and is a portion on the inner peripheral side side portion side. Is an inner protruding grip portion 15B that is arranged so as to project inside the mold main body portion 3.

As shown in FIG. 4, the joint portion forming portion 15A is provided so as to extend in the circumferential direction between the end rib plates 21A and 21B forming the end faces of the pair of split form main body portions 3A and 3B. Further, when the joint portion forming plate member 15 is inserted toward the lining space S through the slit-shaped gap δ, from the formwork surface formed by the outer peripheral portions of the pair of divided formwork body portions 3A and 3B. For example, it is arranged so as to project outward with a projecting height of about 200 mm. Further, it is preferable that the joint portion forming portion 15A is tapered so as to reduce the thickness toward the tip from, for example, about 7 mm to about 2 mm.

The inner protruding grip portion 15B functions as a temporary fixing portion for fixing the joint portion forming plate member 15 until the concrete placed in the lining space S is hardened, and after the concrete is hardened. This is a portion that functions as a handle portion when the plate member 15 is pulled out inside the mold main body portion 3. As shown in FIGS. 5 and 6, the inner protruding grip portion 15B is symmetrically arranged on both sides of the joint portion forming portion 15A and the center line C in the lateral width direction, and is arranged on both sides of the pair of plate sides. A pin insertion hole 16a is formed. As described above, the pair of plate-side pin insertion holes 16a are the end faces of the split formwork main bodies 3A and 3B in a state where the joint forming portion 15A of the joint forming plate member 15 is projected into the lining space S. Is formed at a position that matches each of the pair of end face pin insertion holes 23a formed in the end rib plates 21A and 21B forming the above (see FIG. 4). As a result, as described above, the pin member 26 (see FIG. 4) is inserted into the matched plate-side pin insertion hole 16a and the end face pin insertion hole 23a, so that the joint portion forming plate member 15 is divided into a formwork. It will be attached to the end rib plates 21A and 21B of the main bodies 3A and 3B in a supported state.

Further, in the first embodiment, a pair of action point protrusions 60 are symmetrically arranged on both sides of the inner protrusion grip portion 15B close to the inner peripheral side side portion with the center line C in the lateral width direction interposed therebetween. Is provided as a pull-out engaging portion 15a. The action point protrusion 60, which is the pull-out engaging portion 15a, is, for example, a steel columnar portion having a diameter of about 20 mm, and is formed from one surface of the joint portion forming plate member 15 to the other surface. On the other hand, it protrudes vertically, for example, at a height of about 50 mm, is fixed by welding, for example, and is attached as a unit. The action point protrusion 60 is detachably fixed to the inner protruding grip portion 15B by fitting or screwing into the mounting fixing hole formed in the inner protruding grip portion 15B of the joint portion forming plate member 15, for example. You can also do it. A substrate plate 25 (FIGS. 4 and 7 (FIGS. 4 and 7) in which a tip portion 61a of a rod-shaped member 61 made of a steel rod, which is a drawing edge cutting means 20, is fixed to one of the split formwork main body portions 3A on each of the action point protrusions 60. It is inserted into the gap between a) and (b)) and is engaged.

Further, in the first embodiment, a pair of action point protrusions 60 are arranged symmetrically on both sides of the inner peripheral side side portion of the inner protrusion grip portion 15B with the center line C in the lateral width direction interposed therebetween. A horizontally long rectangular shape that functions as a handle when the joint portion forming plate member 15 is pulled out inside the split formwork main bodies 3A and 3B after the concrete placed in the lining space S is hardened on the outside of the above. A pair of openings 19 are formed for the handle of the concrete.

On the other hand, in the first embodiment, among the split formwork main bodies 3A and 3B on both sides of the slit-shaped gap δ into which the joint forming portion 15A of the joint forming plate member 15 is inserted, for example, the point of action. The substrate plate 25 is fixed to the split formwork main body 3A on one surface side of the joint forming plate member 15 on which the protrusion 60 protrudes, supported by the end rib plate 21A and the reinforcing rib plate 24A. (See FIGS. 4, 7 (a) and 7 (b)), the strip-shaped erection fulcrum plate 62 is erected from the substrate plate 25 inside the split formwork main body 3A, for example, by welding or the like. It is fixed and attached as a unit. The erection fulcrum plate 62 is formed with a concave support portion 62a that is curved in a concave shape at the tip end portion (see FIG. 4).

In the first embodiment, the side peripheral surface of the tip portion 61a of the rod-shaped member 61 made of a steel rod is brought into contact with the concave support portion 62a of the tip portion of the erection fulcrum plate 62, and the rod-shaped member is brought into contact with the side peripheral surface. The tip of the tip portion 61a of 61 is placed between the action point protrusion 60 of the joint portion forming plate member 15 inserted into the slit-shaped gap δ and the substrate plate 25 fixed to the split form main body portion 3A. From the state of being inserted by prying (see FIG. 7A), the rod-shaped member 61 is rotated in the rotation direction indicated by R in the drawing with the concave support portion 62a of the vertical fulcrum plate 62 as a fulcrum. It can be displaced. As a result, the joint portion forming plate member 15 is divided into a formwork by the principle of the lever, with the tip portion of the tip portion 61a of the rod-shaped member 61 which is pried between the action point protrusion 60 and the substrate plate 25 as the action point. Since it is possible to generate a force in the pulling direction Z inside the main body 3A, by slightly pulling out the joint forming plate member 15, the joint forming portion 15A of the joint forming plate member 15 and the joint forming portion 15A of the joint forming plate member 15 can be generated. Adhesion to the hardened surrounding tunnel lining concrete can be cut off.

Further, in the first embodiment, the joint forming portion 15A is projected from the formwork surface formed by the outer peripheral surface portions of the divided formwork main bodies 3A and 3B into the lining space S, and the circumferences of the divided formwork main bodies 3A and 3B are formed. As shown in FIG. 1, the plurality of joint portion forming plate members 15 arranged consecutively in the direction are each divided, which is preferably a boundary portion between the side portions of each pair of adjacent plate members 15. The connecting portion 15C is arranged so as not to generate a gap. Further, in some of these jointly arranged plate members 15 for forming joint portions, the distance between the side portions on both sides is directed from the outer peripheral side to the inner peripheral side of the lining space S. It is a plate member including a V-shaped plate portion having a widened front shape that spreads inward (see FIG. 5).

A part of the plurality of joint portion forming plate members 15 arranged continuously in the circumferential direction has a gap between the side portions on both sides of the lining space S, which spreads toward the inner peripheral side. Since the plate member 15'including the character plate portion is formed, the plate member 15'including the C-shaped plate portion is pulled out in advance so that the plate member 15'includes the shape plate portion 3 in the circumferential direction of the mold body portion 3. The plate members 15 arranged in series avoid being difficult to pull out due to the side portions of the adjacent plate members 15 competing with each other at the split connecting portion 15C, so that each plate member 15 can be pulled out smoothly. It becomes possible to.

As described above, the joint forming portions 15A of the plurality of joint forming plate members 15 are formed in the slit-shaped gap δ between the end rib plates 21A and 21B of the pair of divided formwork main bodies 3A and 3B. By inserting each of them, the joint plate members 15 are arranged and attached in the circumferential direction, and then the inner peripheral surface of the tunnel T covered by the primary lining 5 and the form of the tunnel lining formwork 1 are formed. Work is performed to construct the tunnel lining concrete 4 by placing concrete in the lining space S, which is a concrete placing space formed between the outer peripheral portion of the frame main body 3 and the formwork surface. Is done. In the first embodiment, as shown in FIGS. 2 and 3, the work of constructing the tunnel lining concrete 4 is performed by pumping concrete from two concrete pumps 30 via pumping pipes 31 extending from each of the two concrete pumps 30. , It can be carried out by placing the concrete while supplying it to the lining space S at the same time.

In the present embodiment, the two concrete pumps 30 are arranged in front of and behind the tunnel T in the excavation direction X with the tunnel lining formwork 1 carried into the tunnel T in between, respectively. Concrete 12 is put into the hopper portion of the concrete pump 30 from each concrete mixer wheel 32. Here, the pumping pipes 31 extend from the two front and rear concrete pumps 30, and the concrete 12 injected from each concrete mixer wheel 32 into the hopper portion of each concrete pump 30 is pumped by each of the two systems. It is simultaneously pumped and supplied from the pipe 31 to the lining space S. In this way, by using the two systems of the concrete pump 30 and the pumping pipe 31, the progress of the process for forming the tunnel lining concrete 4 can be effectively accelerated.

The two systems of pumping pipes 31 extending from the two concrete pumps 30 are the main pipe 31a extending inward of the tunnel lining mold 1 and the width direction of the tunnel T from the main pipe 31a via the rotary valve 29. It is configured to include left and right branch pipes 31b branched on both sides. Here, each branch pipe 31b is configured to include a plurality of piece pipes made of straight pipes, curved pipes, and the like having different lengths, and the selected plurality of piece pipes are assembled to form the press-fitting connection ports 11a and 11b. It is arranged so as to be connected to each of them. Further, by rearranging these piece pipes, the branch pipe 31b is formed at the rear end portion of each of the divided formwork main body portions 3A and 3B divided into two of the formwork main body portion 3, preferably each of the excavation directions X. Further, the concrete 12 is placed by switching from the lower press-fitting connection port 11a to the upper press-fitting connection port 11b and connecting, or switching from the upper press-fitting connection port 11b to the zenith press-fitting connection port 27 and connecting. You can do it.

Then, in the first embodiment, when the concrete placed in the lining space S is hardened to form the tunnel lining concrete 4, as shown in FIGS. 7A and 7B, the above-mentioned is described. By the method of pulling out and removing the joint portion forming plate member, each of the plurality of joint portion forming plate members 15 is pulled out from the lining space S to the inside of the formwork main body portion 3, and the work of forming the induced joint is performed. It will be. That is, according to the method of pulling out and removing the joint portion forming plate member of the first embodiment, when each of the joint portion forming plate members 15 is pulled out from the lining space S to the inside of the formwork main body portion 3. In addition, as described above, the side peripheral surface of the tip portion 61a of the rod-shaped member 61 is brought into contact with the concave support portion 62a of the tip portion of the erection fulcrum plate 62, and the tip portion of the rod-shaped member 61 is brought into contact with the side peripheral surface. The tip of 61a is pried between the action point protrusion 60 of the joint portion forming plate member 15 inserted into the slit-shaped gap δ and the substrate plate 25 fixed to the split formwork main body 3A. (See FIG. 7 (a)). After that, the rod-shaped member 61 is rotated and displaced in the rotation direction indicated by R in the drawing, using the concave support portion 62a of the erection fulcrum plate 62 as a fulcrum. As a result, the joint portion forming plate member 15 is divided into a formwork by the principle of the lever, with the tip portion of the tip portion 61a of the rod-shaped member 61 which is pried between the action point protrusion 60 and the substrate plate 25 as the action point. Since it is possible to generate a force in the pulling direction Z inside the main body 3A, the joint forming plate member 15 moves slightly in the Z direction to form the joint of the joint forming plate member 15. The state in which the portion 15A and the hardened surrounding tunnel lining concrete are adhered can be released by cutting the edges, and thereby, the surrounding hardened concrete and the cut-off joint portion forming plate member 15 can be released. Can be smoothly pulled out inside the split formwork main bodies 3A and 3B to be removed.

Therefore, according to the method of pulling out and removing the joint portion forming plate member of the first embodiment, the supporting reaction force when the joint portion forming plate member is pulled out inside the tunnel lining formwork is based on the principle of the lever. By obtaining it directly from the split formwork main body 3A via the fulcrum plate 62 and the substrate plate 25 that serve as fulcrums, it is possible to easily obtain it in a stable state by a simple configuration, which requires a lot of time and effort. It is possible to efficiently pull out and remove each of the plurality of joint portion forming plate members that are continuously installed in the circumferential direction.

Further, in the method of pulling out and removing the joint portion forming plate member of the first aspect, the erection fulcrum provided with the concave support portion 62a at the tip portion is erected from the substrate plate 25 fixed to the split formwork main body portion 3A. The plate 62 does not necessarily have to be attached. For example, from a state in which the tip portion of the tip portion 61a is inserted so as to be inserted between the action point protrusion 60 of the joint portion forming plate member 15 and the substrate plate 25 fixed to the split form main body portion 3A. With the tip of the tip portion 61a in contact with the substrate plate 25 as a fulcrum, the rod-shaped member 61 can be rotated and displaced in a direction R'opposite to the rotation direction indicated by R in FIG. 7A. As a result, the joint plate member 15 is placed inside the split formwork main body 3A by the principle of the joint, with the side surface of the tip of the rod-shaped member 61 in contact with the action point protrusion 60 as the action point. By generating a force in the pulling direction Z and slightly moving the joint forming plate member 15 in the Z direction, the joint forming portion 15A of the joint forming plate member 15 and the hardened surrounding tunnel lining concrete The state in which the and is attached may be released by cutting the edges.

8 (a) and 8 (b) are explanatory views of the method of pulling out and removing the joint portion forming plate member according to the preferred second embodiment of the present invention. In the pull-out / removal method of the second embodiment shown in FIGS. 8A and 8B, the pull-out engaging portion 15a is projected and fixed on both sides of the inner protruding grip portion 15B of the joint portion forming plate member 15. , A pair of reaction force plates 63 having female screw holes 63a, and the pull-out edge cutting means 20 is screwed into each female screw hole 63a of the pair of reaction force plates 63 and rotated to, for example, a split formwork main body. It is composed of a pair of bolt members 64 that are displaced so as to advance and retreat toward the substrate plate 25'fixed to the portions 3A and 3B. By rotating these bolt members 64 and displacing the tip portion so as to press the substrate plate 25'fixed to, for example, the split formwork main bodies 3A and 3B, the joint portion forming plate member 15 is divided into the split formwork. A force in the pulling direction Z is generated inside the main bodies 3A and 3B.

Also by the method of pulling out and removing the joint portion forming plate member according to the second embodiment, a force in the direction Z for pulling out the joint portion forming plate member 15 inside the split formwork main bodies 3A and 3B is generated to generate the joint. By slightly moving the portion-forming plate member 15 in the Z direction, the state in which the joint portion-forming portion 15A of the joint portion-forming plate member 15 and the hardened surrounding tunnel lining concrete are adhered to each other is cut off. Since it can be released, the same action and effect as those of the above-mentioned first embodiment can be obtained.

9 (a) to 9 (d) are explanatory views of a method of pulling out and removing a joint portion forming plate member according to a preferred third embodiment of the present invention. In the pull-out / removal method of the third embodiment shown in FIGS. 9 (a) to 9 (d), the pull-out engaging portion 15a is a plate-side wedge hook formed on the inner protruding grip portion 15B of the joint portion forming plate member 15. The pull-out edge cutting means 20 is formed of a joint hole 65, and is fixed to the split formwork main bodies 3A and 3B in a state of being arranged along the inner protruding grip portion 15B of the joint portion forming plate member 15, and is also anti. It is composed of a reaction force plate 66 provided with a force-side wedge engagement hole 66a, an overlapping plate-side wedge engagement hole 65, and a wedge member 67 driven into the reaction force-side wedge engagement hole 66a. As shown in FIGS. 9A and 9B, the reaction force side wedge engagement hole 66a is displaced inward in the radial direction of the split formwork main bodies 3A and 3B with respect to the plate side wedge engagement hole 65. By driving the wedge member 67 in (see FIG. 9B), the joint forming plate member 15 is displaced relative to the reaction force plate 66 (see FIG. 9D) to form the joint. A force is generated in the direction Z for pulling out the plate member 15 inside the split formwork main bodies 3A and 3B.

Also by the method of pulling out and removing the joint portion forming plate member according to the third embodiment, a force in the direction Z for pulling out the joint portion forming plate member 15 inside the split formwork main bodies 3A and 3B is generated to generate the joint. By slightly moving the portion-forming plate member 15 in the Z direction, the state in which the joint portion-forming portion 15A of the joint portion-forming plate member 15 and the hardened surrounding tunnel lining concrete are adhered to each other is cut off. Since it can be released, the same action and effect as those of the above-mentioned first embodiment can be obtained.

The present invention is not limited to each of the above embodiments, and various modifications can be made. For example, the formwork body of the tunnel lining formwork does not necessarily have to be divided into two parts, and may be divided into three or more parts. The method for pulling out and removing the joint portion forming plate member of the present invention also when the joint portion forming plate member inserted into the slit-shaped gap between the adjacent ends is pulled out and removed after the concrete has hardened. Can be adopted.

1 Formwork for tunnel lining 2 Stand 3 Formwork body 3A, 3B Divided formwork body 4 Tunnel lining concrete (lining concrete)
15 Joint plate member 15A Joint forming portion 15B Inner protruding grip portion 15a Pull-out engaging portion 16a Plate side pin insertion hole 20 Pull-out edge cutting means 21A, 21B End rib plate 23a End face pin insertion hole 25, 25'Board plate 26 Pin member 60 Action point protrusion 61 Rod-shaped member 61a Tip part 62 Standing fulcrum plate 62a Concave support part 63 Reaction force plate 63a Female screw hole 64 Bolt member 65 Plate side wedge engagement hole 66 Reaction force plate 66a Reaction force side wedge engagement Practical hole 67 Wedge member δ Slit-shaped gap S Lining space T Tunnel X Tunnel excavation direction (axial direction of tunnel lining formwork)
Direction to pull out the plate member for forming the Z joint

Claims (6)

In the mountain tunnel construction method, an induced joint is formed in the tunnel lining concrete to be constructed, which is detachably attached to the middle part in the axial direction of the tunnel lining mold installed when constructing the tunnel lining concrete. This is a method of pulling out and removing the joint portion forming plate member for pulling out and removing the joint portion forming plate member for removing the cast concrete after it has hardened.
The tunnel lining formwork includes a formwork portion that can move in the tunnel excavation direction and a formwork body portion that is supported by the gantry portion and forms a lining space between the inner wall surface of the tunnel. Ori,
The formwork body is composed of a plurality of split formwork bodies divided in the excavation direction of the tunnel, and a slit-shaped gap is formed between the adjacent ends of the divided formwork body. A plurality of the joint portion forming plate members are inserted into the slit-shaped gaps that are continuously formed over the entire circumference, and the inserted joint portion forming plate member is an outer peripheral portion. In a state where the joint forming portion on the side is projected into the lining space, the inner protruding grip portion on the inner peripheral portion side is fixed to the split formwork main body portion, and is continuously arranged and attached in the circumferential direction. Ori,
The joint portion forming plate member includes a pull-out engaging portion for engaging the pull-out edge cutting means with the inner protruding grip portion, and the pull-out edge cutting means is engaged with the pull-out engaging portion. By obtaining a supporting reaction force from the split formwork body and displacement, a force is generated in the direction of pulling out the joint forming plate member inside the split formwork body, and the joint forming plate is generated. The joint forming portion of the member is trimmed from the surrounding hardened concrete that is in close contact with the joint forming portion.
After that, a method of pulling out and removing the joint portion forming plate member by pulling out and removing the joint portion forming plate member inside the split formwork main body portion. The pull-out engaging portion comprises an action point protrusion vertically protruding and fixed from the inner protrusion grip portion of the joint portion forming plate member, and the pull-out edge cutting means includes the action point protrusion and the split formwork main body. It is composed of a rod-shaped member having a tip portion inserted between the portions, and the rod-shaped member having the tip portion inserted is displaced in the rotational direction. The method for pulling out and removing a joint portion forming plate member according to claim 1, wherein a force in a pulling direction is generated inside the portion. The method for pulling out and removing a joint portion forming plate member according to claim 2, wherein the action point protrusion is detachably fixed to the inner protruding grip portion of the joint portion forming plate member. The action point protrusions are arranged and fixed in pairs on both side portions of the joint portion forming plate member across the circumferential center line in the inner protrusion grip portion, and the tip portions of the two rod-shaped members are fixed. By inserting from the outside between each of the action point protrusions and the split formwork main body and displacement in the rotational direction, the joint portion forming plate member is placed in the split formwork main body by the principle of the lever. The method for pulling out and removing a joint portion forming plate member according to claim 2 or 3, wherein a force in a pulling direction is generated inside the portion. The pull-out engaging portion is composed of a pair of reaction force plates having female screw holes, which are projected and fixed on both sides of the inner protruding grip portion of the joint portion forming plate member, and the pull-out edge cutting means is a pair of pull-out edge cutting means. It is composed of a pair of bolt members that are screwed into the female screw holes of each of the reaction force plates and are displaced so as to advance and retreat toward the split formwork main body by rotating, and these bolt members are rotated. The joint portion according to claim 1, wherein the tip portion is displaced so as to press the split form main body portion to generate a force in the direction of pulling out the joint portion forming plate member inside the split form main body portion. Method of pulling out and removing the forming plate member. The pull-out engaging portion comprises a plate-side wedge engaging hole formed in the inner protrusion grip portion of the joint portion forming plate member, and the pull-out edge cutting means is the inner protrusion of the joint portion forming plate member. A reaction force plate that is fixed to the split mold main body in a state of being arranged along the grip portion and has a reaction force side wedge engagement hole, and an overlapping plate side wedge engagement hole and the anti-force side wedge engagement hole. It consists of a wedge member that is driven into the force side wedge engagement hole, and the reaction force side wedge engagement hole is displaced inward in the radial direction with respect to the plate side wedge engagement hole. By driving the wedge member, the joint portion forming plate member is displaced relative to the reaction force plate, and the joint portion forming plate member is pulled out inside the divided mold main body portion. The method for pulling out and removing a joint plate member according to claim 1, wherein a force is generated.

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