JP7285519B2 - Mounting structure of joint forming plate member - Google Patents

Description

TECHNICAL FIELD The present invention relates to a mounting structure for a joint forming plate member, and in particular, it is mounted in a removable manner in an axially intermediate portion of a tunnel lining formwork to form an induced joint in the constructed tunnel lining concrete. It relates to a mounting structure of a joint forming plate member for the purpose.

For example, in tunnel construction methods such as the mountain tunnel construction method, a construction method that uses a tunnel lining formwork called centr as a method for forming tunnel lining concrete that is constructed by covering the natural ground on the inner peripheral surface of an excavated tunnel. is generally employed (see, for example, Patent Documents 1 and 2). For example, as shown in FIG. 10, the tunnel lining formwork 50 is installed along the inner peripheral surface of a tunnel 53 having a shape including an arch-shaped portion 52 such as a horseshoe, extending from the side wall portion 55 to the upper portion of the tunnel 53. Plain concrete is preferably cast in the lining space 61 between the installed tunnel lining formwork 50 and the natural ground covered with the shotcrete 54 on the inner peripheral surface of the tunnel 53. By setting and hardening, the tunnel lining concrete is formed so as to be continuous with the concrete of the inverted portion 51 at the bottom of the tunnel.

Further, as the tunnel lining formwork 50, for example, in addition to the prefabricated tunnel lining formwork called a bara center, a mobile tunnel lining formwork called a slide center is known. As the excavation work progresses, the tunnel lining formwork 50 is re-installed every predetermined construction span of, for example, about 10.5 m, and the tunnel lining formwork is installed from the rear to the front in the excavation direction of the tunnel 53. Using the frame 50, the lining concrete of the side and upper part of the tunnel 53 is placed and formed in sequence.

Then, in order to cast the lining concrete for the side and upper part of the tunnel using the tunnel lining formwork 50, for example, as shown in FIGS. As a height area where concrete can be cast from the inspection window 56 provided in the formwork 50, for example, the area from the side wall portion 55 of the tunnel 53 to the shoulder portion of the arch-shaped portion 52 is inspected through the inspection window 56. A vibrator 58 is inserted through the inspection window 56, and the concrete 57 is placed while compacting the supplied concrete 57 (see FIGS. 11(a) to 11(c)). After that, as a height region where it is difficult to compact with the vibrator 58 while supplying the concrete 57 from the inspection window 56, the crown portion 59 (see FIG. 104) of the tunnel 53 is A pattern is employed in which concrete 57 is press-fitted by a blow-up method from a blow-up input port 60 provided at the top end of the lining form 50 and poured to form the concrete 57 of the crown portion 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 part 55, concrete 57 is poured through the lower inspection window 56 and compacted using the vibrator 58. (see FIG. 11(a)), and a step of compacting using a vibrator 58 while pouring concrete 57 through an inspection window 56 in the middle toward the arch-shaped portion 52 at the top of the side wall portion 55 (see FIG. 11 ( b)), and a step of compacting using a vibrator 58 while pouring concrete 57 up to the front of the crown 59 of the arch-shaped portion 52 through the upper inspection window 56 and, if necessary, the blow-up inlet 60. (See FIG. 11(c)) and a step of press-fitting concrete 57 from the portion of crown 59 on the side of existing lining concrete 62 through blow-up injection port 60 by a blow-up method, and filling concrete up to end formwork 63. (Refer to FIG. 11(d)), the lining concrete is placed.

JP 2001-280094 A Japanese Patent Application Laid-Open No. 2003-262096 JP 2015-67949 A

On the other hand, in the tunnel construction method in recent years, due to improvements in excavation technology, the progress of the process for forming the lining concrete, from concrete placement to curing and removal of the formwork for the tunnel lining, affects the face surface of the tunnel. It is no longer possible to keep up with the progress of the excavation process. For this reason, as a technique for accelerating the progress of the process of forming lining concrete, a plurality of concrete pumps are used (see, for example, Patent Document 3), or a tunnel lining having a construction extension of about 10.5 m, which is generally used, is used. Instead of the construction formwork, a long-span tunnel lining formwork preferably having a construction extension of about 18m to 22m is used to extend the construction span of the tunnel lining concrete performed in one cycle, thereby shortening the construction period. is being considered to be shortened.

In addition, when using a long-span tunnel lining form having a construction extension of preferably about 18 m to 22 m and extending the construction span of the tunnel lining concrete performed in one cycle, in the middle part of the construction span, Since cracks are likely to occur due to drying shrinkage and temperature shrinkage, especially when forming tunnel lining concrete with a long construction span, cracks due to drying shrinkage and temperature shrinkage are induced in the intermediate part. It is desirable to provide joints. For this reason, the applicant of the present application proposed, for example, Japanese Patent Application No. 2018-147241 (Japanese Unexamined Patent Application Publication No. 2020-20246), as a method of providing an induced joint in the intermediate portion of the tunnel lining concrete, for a formwork for tunnel lining. A plurality of joint forming plate members are protruded from the formwork surface into the lining space, arranged in series in the circumferential direction and attached so as to be removable, and when the concrete placed in the lining space hardens, A method is disclosed for forming an induced joint by withdrawing a joint forming plate member from a lining space.

Here, in the method for forming an induced joint described in Japanese Patent Application Laid-Open No. 2020-20246, the formwork main body of the formwork for tunnel lining, which forms a lining space between itself and the inner wall surface of the tunnel, is used to excavate the tunnel. A slit-shaped gap formed between the adjacent ends of the pair of split formwork main bodies is formed by a pair of split formwork main bodies divided in two directions, and the joint forming part is a lining space. By inserting a plurality of joint forming plate members so as to protrude inward, and fixing the joint forming part to the end of one of the split form main bodies in a state in which the joint forming part protrudes into the lining space , each of the joint forming plate members are mounted so as to be continuously arranged in the circumferential direction.

Furthermore, the applicant of the present application, for example, in Japanese Patent Application No. 2019-13691, standing from the outer peripheral surface of the end edge of the main body of the split formwork on both sides located on both sides of the slit-shaped gap, the shape of a right triangle or A chamfering member having a right-angled trapezoidal cross-sectional shape is continuously attached along the entire circumference in a state of protruding into the lining space, so that after the concrete placed in the lining space has hardened, To effectively avoid chipping of a corner of an induced joint when the joint forming plate member is pulled out from a lining space, and to effectively avoid the chipping of the corner of the joint forming plate member, and to provide a joint forming portion of the joint forming plate member. It is disclosed that the adhesion area with the tunnel lining concrete is reduced so that the operation of pulling out the joint forming plate member to the inside of the form body can be performed more smoothly.

However, the slit-shaped gap between the ends of the pair of split form main bodies divided into two and the width of the guide groove formed between the pair of chamfered members make it easy to insert the joint forming plate member. In order to do so, the thickness of the plate member for forming the joint is wider than the thickness of the plate member. The width of the gap and the guide groove increases, and a considerable gap is generated between the inserted joint forming plate member and the paste in the concrete placed in the lining space. Dirt and mortar flow out as slag to the inside of the main body of the split formwork, impairing the aesthetic appearance and degrading the working environment, and requiring a lot of labor for cleaning work.

The present invention closes the gap between a slit-shaped gap or a guide groove and an inserted joint forming plate member due to distortion of the split formwork main body during assembly of the split formwork main body, for example. As a result, the joint forming plate member can effectively prevent paste and mortar in the concrete placed in the lining space from flowing out as slag to the inside of the main body of the split form. The purpose is to provide a mounting structure for

In the mountain tunnel construction method, the present invention provides a tunnel lining form that is installed when constructing the tunnel lining concrete that covers the inner wall surface of the tunnel. An attachment structure for a joint forming plate member that is movably attached to form an induced joint in a tunnel lining concrete to be constructed, wherein the tunnel lining formwork is movable in the excavation direction of the tunnel. and a form body supported by the stand and forming a lining space between itself and the inner wall surface of the tunnel. The form body is divided into two parts in the tunnel excavation direction. A slit-shaped gap is continuously formed over the entire circumference between the adjacent ends of the pair of split formwork main bodies. A plurality of the joint forming plate members are inserted into the slit-shaped gaps, and the inserted joint forming plate members move the joint forming portions on the outer periphery side to the lining space. In the protruding state, the inner protruding grip part on the inner peripheral side is fixed to the main body part of the split formwork, and the grip part is continuously arranged in the circumferential direction and attached to both sides of the slit-shaped gap. A pair of face wooden members stand upright from the outer peripheral surface of the edge of each of the main body portions, and extend along the edge while holding the guide groove between the opposing surfaces. Each of the joint forming plate members is inserted into the slit-shaped gap and the guide groove formed by the face wooden members on both sides so that the outer peripheral portion of the joint forming portion is aligned with the face wooden member. at least one of the face wooden members on both sides is a flexible face wooden member having flexibility. The flexible face plate member is formed with through-holes that are continuous in the circumferential direction. extends from the end of the flexible panel member to the inside of the tunnel lining form and is connected to the tension adjusting member, and the flexible panel member is connected to the A mounting structure for a joint forming plate member that is deformed so as to come into close contact with the joint forming plate member inserted in the guide groove by applying a tensile force to the tensile wire member by a tension adjusting member. By providing, the above object is achieved.

In the mounting structure of the joint forming plate member of the present invention, the face wooden member has a right-angled triangular shape or a right-angled It preferably has a trapezoidal cross-sectional shape.

Further, in the mounting structure of the joint forming plate member of the present invention, it is preferable that the flexible facing lumber is formed using a rubber material.

Further, in the attachment structure of the joint forming plate member of the present invention, it is preferable that the tensile wire member is made of a wire member.

Furthermore, in the mounting structure of the joint forming plate member of the present invention, it is preferable that the tension adjusting member is formed of a turnbuckle.

According to the mounting structure of the joint forming plate member of the present invention, for example, when the split form main body is distorted during assembly of the split form main body, the slit-shaped gap or guide groove and the inserted joint part By closing the gap between the forming plate member and the concrete placed in the lining space, for example, paste and mortar, it is possible to effectively prevent the outflow of the slag to the inside of the main body of the split formwork. can be avoided.

2 is a schematic cross section of a tunnel lining form in which a plurality of joint forming plate members are arranged in series in the circumferential direction of the main body of the split form with the joint forming part protruding into the lining space; . FIG. 2 is a schematic vertical cross-sectional view for explaining a tunnel lining form to which a joint forming unit is attached, which forms a mounting structure for a joint forming plate member according to a preferred embodiment of the present invention. FIG. 4 is a schematic plan view illustrating a tunnel lining form to which a joint forming unit is attached, which forms a mounting structure for a joint forming plate member according to a preferred embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view taken along line AA of FIG. 1 at part A' of FIG. 2, explaining a mounting structure of a joint forming plate member according to a preferred embodiment of the present invention; FIG. 5 is a schematic enlarged cross-sectional view of a main part of FIG. 4 for explaining a mounting structure of a joint forming plate member according to a preferred embodiment of the present invention; FIG. 4 is a schematic vertical cross-sectional view illustrating a configuration in which a tensile force is applied to a tensile linear member by a tension adjusting member; It is a front view of a plate member for joint part formation. Fig. 8 is a side view of the joint forming plate member (view in the direction of arrow B in Fig. 7); FIG. 9 is a cross-sectional view along CC of FIG. 8; FIG. 3 is a schematic cross-sectional view for explaining a state in which a tunnel lining formwork is installed along the inner peripheral surface of a tunnel in a conventional method for placing tunnel lining concrete. 1(a) to 1(d) are schematic side views, partly in cross-section, for explaining the work procedure of a conventional tunnel lining concrete placing method.

A mounting structure 10 (see FIGS. 4 and 5) for a joint forming plate member according to a preferred embodiment of the present invention is, for example, used in a tunnel construction method such as a mountain tunnel construction method, as shown in FIGS. Tunnel lining concrete 4 (see Figs. 2 and 3) constructed to cover the inner peripheral surface of the tunnel T, which is generally used as a tunnel lining form called a center, is about 10.5m long. When forming using a long-span tunnel lining form 1 preferably having a construction extension of about 18 m to 22 m instead of a tunnel lining form having a construction extension of , the tunnel lining concrete 4 It was adopted as a structure for forming induced joints that induce cracks due to drying shrinkage and temperature shrinkage in the middle part of the construction span.

That is, in the recent tunnel construction method, due to improvements in excavation technology, the progress of the steps for forming the lining concrete 4, from concrete placement to curing and removal of the tunnel lining formwork 1, is controlled by the tunnel T. In many cases, it is not possible to follow the progress of the process of excavating the face of the tunnel, and it is often not constructed efficiently. Instead of a formwork, a long-span tunnel lining formwork 1 preferably having a construction extension of 10.5 m or more is used, for example, a long-span tunnel lining formwork 1 having an extension of about 18 to 22m. As a result, the construction span of the lining concrete 4 performed in one cycle is increased, and the concrete is cast simultaneously from two systems of pressure-feeding pipes 31 using two concrete pumps 30 to cast concrete. By shortening the working time during the process, the progress of the process for forming the lining concrete 4 can be hastened.

In addition, in this embodiment, by using the long-span tunnel lining formwork 1, if the extension of the construction span of one cycle of the lining concrete 4 is increased, only at the boundary between the adjacent construction spans, the concrete Cracks due to drying shrinkage and temperature shrinkage cannot be sufficiently absorbed, and cracks are likely to occur in the middle part of the construction span. For this reason, a joint forming plate member 15 for forming an induced joint that induces cracking due to drying shrinkage or temperature shrinkage is inserted into the slit-shaped gap δ in the intermediate portion of the construction span (see FIG. 4). , a pair of split formwork main bodies that are arranged in series in the circumferential direction with the joint part forming part 15A protruding into the lining space S and constitute the formwork main body part 3 of the tunnel lining formwork 1. It is fixedly attached, preferably at one end of the parts 3A, 3B. In the mounting structure 10 of the joint forming plate member of the present embodiment, for example, the split form main bodies 3A and 3B are distorted at the time of assembly of the split form main bodies 3A and 3B, so that they are inserted into the slit-shaped gap δ. For example, paste and mortar in the concrete placed in the lining space S flows out as slag into the split form main bodies 3A and 3B from the gap between the joint forming plate member 15 and the joint forming plate member 15. It has a function to effectively prevent

The mounting structure 10 of the joint forming plate member of the present embodiment is the tunnel lining formwork 1 installed when constructing the tunnel lining concrete 4 covering the inner wall surface of the tunnel T in the mountain tunnel construction method. a joint forming plate member 15 for forming an induced joint in the tunnel lining concrete 4 to be constructed, which is detachably attached to the intermediate portion of the tunnel lining form 1 in the axial direction X, Used as a structure for attachment. As shown in FIGS. 1 to 3, the tunnel lining formwork 1 includes a pedestal part 2 that can move in the tunnel excavation direction X, which is also the axial direction X of the tunnel lining formwork 1, and the pedestal part 2. and a form main body 3 that forms a lining space S between itself and the inner wall surface of the tunnel T. The formwork main body 3 is composed of a pair of split formwork main bodies 3A and 3B divided in the tunnel excavation direction X, and adjacent ends of the pair of split formwork main bodies 3A and 3B are divided. A slit-like gap δ (see FIGS. 4 and 5) is continuously formed between them over the entire circumference. A plurality of joint forming plate members 15 are inserted into the slit-shaped gaps δ, and the inserted joint forming plate members 15 divide the joint forming portion 15A on the outer peripheral side into the lining space S. In the state where it protrudes inward, the inner protruding gripping portion 15B on the inner peripheral side is preferably fixed to one of the split mold body portions 3A across a slit-shaped gap δ, and is arranged continuously in the circumferential direction. It is As shown in FIGS. 4 and 5, a pair of split formwork main bodies 3A and 3B, which are positioned on both sides of a slit-shaped gap δ, are erected from the outer peripheral surface of the edge of each of the pair of split formwork main bodies 3A and 3B. The face wooden members 20h, 21h are fixed along the edge portions with the guide grooves 28 held between the facing surfaces 20i, 21i. Each joint forming plate member 15 is inserted into a slit-shaped gap δ and a guide groove 28 formed by the face wooden members 20h and 21h on both sides, so that the outer periphery of the joint forming portion 15A is formed by the face wooden members 20h and 21h. are attached to the split form main bodies 3A and 3B so as to be able to be pulled out in a state arranged outside the ends of the split formwork. As shown in FIG. 5, at least one of the side wooden members 20h and 21h on both sides (the side wooden member 20h in this embodiment) is a flexible side wooden member 12 having flexibility. A tensile wire-like member 13 is continuously inserted through through-holes 12a of the elastic wooden member 12 which are continuous in the circumferential direction. As shown in FIG. 6, both ends of the tension wire members 13 extend from the ends of the flexible panel members 12 to the inside of the tunnel lining formwork 1 to form tension adjustment members 14. connected to The flexible surface wooden member 12 is brought into close contact with the surface of the joint forming plate member 15 inserted into the guide groove 28 by applying a tensile force to the tensile wire member 13 by the tension adjusting member 14 . transform.

Further, in the present embodiment, the plate mounting pedestal 20 and the facing pedestal 21, which constitute the joint forming unit 40 together with the joint forming plate member 15, are preferably provided at the respective ends of the split form main bodies 3A and 3B. A slit-like gap δ (Fig. 4, 5) are formed continuously over the entire circumference.

In this embodiment, the tunnel lining formwork 1 having a plurality of joint forming plate members 15 attached to the intermediate portion is a slide center that can move in the extension direction (excavation direction) X of the tunnel T, For example, it is a long-span center with an extension of about 18 to 22m. 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. 2015-67949, except that it is a long-span center.

That is, as shown in FIGS. 1 to 3, the tunnel lining formwork 1 is connected and integrated in the excavation direction X of the tunnel T (see FIG. 1) with a pedestal 2 comprising a plurality of gate-type carriages 2A. , supported by the gantry 2 of the integrated portal carriage 2A and arranged along the inner peripheral surface of the tunnel T covered by the primary lining 5 made of, for example, shotcrete to form a lining space It is configured including a formwork main body 3 that forms the formwork surface on the inside of S. A portal carriage 2A that constitutes the gantry section 2 includes a base section 2a and support leg sections 2b that support the base section 2a. At the lower ends of the support legs 2b, there are provided running parts 7 that can run along rails 6 laid on the floor of the tunnel T. It can move in the excavation direction X.

The form 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 apart from the inner peripheral surface of the tunnel T by a predetermined distance. By being arranged, a lining space S with a predetermined thickness is formed, which is a concrete placing space. As shown in FIG. 1, the formwork main body 3 includes an upper formwork 3a that forms a lining space S above the arch-shaped portion 52 of the tunnel T, and a lower portion and both side wall portions of the arch-shaped portion 52. 55 and a pair of lower end forms 3c forming a lining space S below the side wall portion 55 connected to the concrete of the inverted portion. consists of The upper formwork 3a is supported vertically by a plurality of elevating jacks 8 provided on the base portion 2a of the portal carriage 2A that constitutes the gantry portion 2 so as to be vertically movable. The pair of side molds 3b are rotatably connected to the lower ends on both sides of the upper mold 3a via rotary couplings 3d, respectively. It is rotatably connected to the lower end of 3b via a lower rotary connecting portion 3e. One end of the side formwork 3b and the lower end formwork 3c are connected to the other ends of telescopic jacks 9a and 9b connected to the gate-type carriage 2A. Thus, the side molds 3b and the lower end molds 3c can be rotated with respect to the upper molds 3a and the side molds 3b.

As a result, the tunnel lining formwork 1 can expand and contract the formwork main body 3 by expanding and contracting the elevating jacks 8 and the telescopic jacks 9a and 9b. The formwork main body 3 can be assembled along the inner peripheral surface of the tunnel T, and the formwork main body 3 can be removed from the mold and then moved in the excavation direction X inside the tunnel T.

In the present embodiment, the upper formwork 3a and the side formwork 3b of the formwork main body 3 are provided with a plurality of press-fit connection ports 11a and 11b at two locations each spaced apart in the excavation direction X of the tunnel T. (see FIG. 2). A plurality of zenith press-fit connection ports 27 are formed at two locations in the excavation direction X of the tunnel T at intervals in the ridge portion of the upper mold 3a of the mold main body 3 . These press-in connection ports 11a, 11b, and 27 are used for the purpose of pouring or press-fitting concrete for lining, which is pressure-fed through the pressure-feeding pipe 31, into the lining space S, as will be described later. be done.

In this embodiment, the formwork main body 3 of the tunnel lining formwork 1 is divided into two parts in the excavation direction X of the tunnel T (horizontal direction in FIGS. 2 and 3) as described above. It is composed of split mold body parts 3A and 3B. A pair of split formwork main bodies 3A and 3B are arranged so that a constant-width interval portion d (see FIGS. 2 and 3) is formed over the entire circumference between the adjacent end faces. 2, and a joint forming unit 40 is attached over the entire circumference to the space d between the pair of split formwork main bodies 3A and 3B. By attaching the joint forming unit 40 to the gap d of the pair of split form main bodies 3A and 3B over the entire circumference, between the ends of the pair of split form main bodies 3A and 3B, A slit-like gap δ (see FIGS. 4 and 5) having a constant width is formed along the entire circumference. In addition, in the formed slit-shaped gap δ, a plurality of joints for forming an induced joint in the intermediate part of each construction span L (= 18 m) are supported by the plate mounting base 20 constituting the joint part forming unit 40. The joint part forming plate member 15 projects the joint part forming part 15A into the lining space S, and is arranged continuously over the entire circumference in a state in which the joint part forming part 15A is inserted so as to be able to be pulled out. (See Figure 1).

The joint forming unit 40 is one of the split form main bodies sandwiching a constant width interval d (see FIGS. 2 and 3) in the form main body 3 formed by the above-described pair of split form main bodies 3A and 3B. A plate mounting pedestal that is fixed to the end of the part 3A over the entire circumference to form a slit-like gap δ over the entire circumference with the end of the other split form main body part 3B. 20 (see FIG. 4) is detachably attached to the plate mounting pedestal 20, and is removably inserted in a state in which the joint forming portion 15A protrudes into the lining space S through a slit-shaped gap δ. (see FIG. 4), and a plurality of joint forming plate members 15 arranged in series over the entire circumference (see FIG. 1). The end of the plate mounting pedestal 20 is the end of one split formwork main body 3A that forms a slit-like gap δ with the other end of the split formwork main body 3B. Plate-side pin insertion holes 16a are formed in at least two locations (two locations in the present embodiment) in the inner protruding grip portion 15B, which is a portion on the inner peripheral side of the joint forming plate member 15 ( See Figure 7). The mounting surface portion 20a of the plate mounting base 20 has a plate-side pin insertion hole 16a in a state in which the joint forming portion 15A, which is the portion of the joint forming plate member 15 on the outer peripheral side, protrudes into the lining space S. A pedestal-side pin insertion hole 23a is formed at a position corresponding to (see FIG. 4). By inserting the pin member 26 into the plate-side pin insertion hole 16a and the pedestal-side pin insertion hole 23a which are aligned, the joint forming plate member 15 is fixed while being supported by the plate mounting pedestal 20, and is mounted. It is

Further, in the present embodiment, as shown in FIG. 4, preferably, the edge portion of the other split form main body portion 3B and the one split form main body portion located on both sides of the slit-shaped gap δ The surface wooden members 21h and 20h, preferably having a right-angled triangular or right-angled trapezoidal cross-sectional shape, stand upright from the outer peripheral surface of the edge of the plate mounting base 20, which is the edge of 3B, and form the lining space S. It is preferably attached continuously over the entire circumference in the circumferential direction of each of the split formwork main bodies 3A and 3B in a state of protruding outward.

Furthermore, in the present embodiment, the plate mounting base 20 is preferably arranged in pair with the end of the other split formwork main body 3B sandwiching the space d between the pair of split formwork main bodies 3A and 3B. The opposing pedestal 21 is mounted integrally over the entire circumference as a constituent member of the joint forming unit 40 . A slit-shaped gap δ is formed over the entire circumference between the end of the opposing pedestal 21 and the end of the plate mounting pedestal 20 as the end of the other split form main body 3B. It has become. Standing from the outer peripheral surface of the end edge of the opposing pedestal 21, which is the end edge of the other split formwork main body 3B, the above-described face wooden member 21h is continuously attached along the entire circumference in the circumferential direction. It is

In the present embodiment, the plate mounting pedestal 20 that constitutes the joint forming unit 40 includes a plurality of joint forming plate members 15 (see FIG. 1) continuously arranged along the entire circumference of the lining space S in the circumferential direction. ), preferably the same number of unit mounting pedestals as the joint forming plate members 15, are continuously arranged in the circumferential direction of the lining space S, and one split form body A plurality of unit mounting pedestals arranged in series in the circumferential direction are mounted as an integrated member by fixing them to the ends of the portion 3A.

The opposing pedestal 21 attached to the end of the other split formwork main body 3B is also arranged along the entire circumference of the lining space S in the same manner as the plate mounting pedestal 20 arranged to be paired therewith. A plurality of unit facing pedestals formed corresponding to each of the plurality of joint forming plate members 15 (see FIG. 1) arranged in series, preferably the same number as the plate members 15, are arranged around the lining space S. By arranging them in series in the direction and fixing them to the ends of the other split form main body 3B, the unit facing pedestals that are consecutively arranged in the circumferential direction are attached as an integrated member.

The joint forming plate member 15, which constitutes the joint forming unit 40 together with the plate mounting base 20 and the facing base 21, is preferably made of aluminum or steel and has a thickness of, for example, about 6 to 10 mm, as shown in FIGS. It is formed using a metal plate having a thickness (about 7 mm in thickness in this embodiment). The joint forming plate member 15 has, for example, a vertical width of about 300 to 600 mm and a horizontal width of about 400 to 700 mm. It has a quadrilateral planar shape having side portions and side portions on both left and right sides. The outer peripheral side portion has a curved shape along the curved shape of the form surface formed by the outer peripheral portions of the split formwork main bodies 3A and 3B, the plate mounting pedestal 20, and the opposing pedestal 21 in the circumferential direction. The joint forming plate member 15 has a joint forming portion 15A (hatched portion in FIG. 7) arranged so as to protrude from the formwork surface into the lining space S at the portion on the side of the outer peripheral side. The part on the side of the peripheral side serves as an inward projecting grip part 15</b>B that projects inwardly from the form main body 3 .

As shown in FIG. 4, the joint forming portion 15A is a slit-like gap provided extending in the circumferential direction between the edge portion of the plate mounting base 20 and the edge portion of the opposing base 21. When the joint forming plate member 15 is inserted toward the lining space S via δ, a protrusion height of, for example, about 200 mm from the formwork surface by the outer peripheral portion of the plate mounting base 20 and the facing base 21 are arranged so as to protrude outward. Further, the joint forming portion 15A is tapered so that the thickness is reduced from about 7 mm to about 2 mm toward the tip. Both surfaces of the portion 15A are coated with a known friction reducing material that absorbs water and swells, such as a friction reducing material containing acrylic resin having high water absorption, and containing a highly water-absorbing resin. ing. As a result, the operation of pulling out the joint forming plate member 15 to the inside of the form body 3 can be performed more smoothly after the concrete placed in the lining space S has hardened.

The inward protruding gripping portion 15B functions as a temporary fixing portion for fixing the joint portion forming plate member 15 to the plate mounting base 20 until the concrete placed in the lining space S hardens. It is a portion that functions as a handle when the plate member 15 is pulled out to the inside of the form body 3 after the concrete has hardened. As shown in FIGS. 7 and 8, the surface of the gripping portion 15B opposite to the surface facing the plate mounting base 20 (front surface in FIG. 7) has a center line c in the width direction. Circular bosses 16 are arranged symmetrically on both sides and protrude integrally, and in the central part of these circular bosses 16, the plate is inserted through the circular boss 16 and the joint forming plate member 15 A side pin insertion hole 16a is formed respectively. The plate-side pin insertion hole 16a is a base-side pin insertion hole formed in the mounting surface portion 20a of the plate mounting base 20 in a state in which the joint forming portion 15A of the joint forming plate member 15 protrudes into the lining space S. 23a and formed in a matching position (see FIG. 4). As a result, as described above, by inserting the pin member 26 (see FIG. 4) into the plate-side pin insertion hole 16a and the base-side pin insertion hole 23a that are aligned, the joint forming plate member 15 can be attached to the plate. It is attached while being supported by the pedestal 20 .

In addition, in the present embodiment, the joint forming plate member 15 is attached to the inner peripheral side end portion of the inward protruding grip portion 15B, which is adjacent to the inner peripheral side portion, after the concrete placed in the lining space S has hardened. A pair of openings is formed by symmetrically arranging horizontally long rectangular handle openings 19 on both sides of the center line c in the width direction, which function as handle parts when pulling out the mold main body 3 to the inside. It is

Furthermore, in the present embodiment, the inner peripheral side end portion of the inwardly protruding grip portion 15B adjacent to the inner peripheral side portion vertically protrudes from the central portion of the surface facing the plate mounting base 20 in the width direction. A fastening piece 18 is joined together. As shown in FIG. 9, the overhanging fastening piece 18 is formed with a notch hole 18a that is cut out in a U-shape from the side of the overhanging distal end side to the base end side. In the cutout hole 18a, the joint forming portion 15A of the joint forming plate member 15 is protruded into the lining space S, and the rotary support bracket is attached to the mounting surface portion 20a of the plate mounting base 20 as described above. A fixing bolt 25b rotatably supported via 25a can be detachably fastened using a nut member 25c (see FIG. 4).

In the present embodiment, a plurality of joints arranged continuously in the circumferential direction of the form main body 3 by projecting the joint forming part 15A into the lining space S from the form surface formed by the outer peripheral surface 21b of the plate mounting base 20. As shown in FIG. 1, the part-forming plate members 15 are preferably arranged so that each split connection part 15a, which is a boundary part between the side parts of each pair of adjacent plate members 15, does not have a gap. are placed in In some of the plurality of joint forming plate members 15 arranged in series, the interval between the side portions on both sides of the lining space S is oriented from the outer peripheral side to the inner peripheral side. It is a V-shaped plate member 15' having an inwardly widened front face shape.

Some of the plurality of joint portion forming plate members 15 arranged in series in the circumferential direction are such that the interval between the side portions on both sides widens toward the inner peripheral side of the lining space S. Since the V-shaped plate member 15 ′ is formed, the plate member 15 arranged continuously in the circumferential direction of the form body 3 can be removed by pulling out the V-shaped plate member 15 ′. 1, it is possible to smoothly pull out each plate member 15 by avoiding difficulty in pulling out due to competition between the side parts of the adjacent plate members 15 at the split connection part 15a.

In this embodiment, a plate mounting pedestal 20, an opposing pedestal 21, and a plurality of In order to install the joint forming unit 41 comprising the joint forming plate member 15, the plate mounting base 20 and the facing base 21 arranged in a pair with the plate mounting base 20 are mounted on the split form main bodies 3A and 3B. installed along the entire circumference of the That is, as described above, the plate mounting pedestal 20 connects a plurality of unit mounting pedestals, for example, adjacent unit mounting pedestals by appropriately joining them together in the circumferential direction, and also connects the one split formwork main body 3A. can be easily attached to the end face joining plate 3f that forms the end face of the end of one of the split formwork main bodies 3A. In addition, as described above, the opposing pedestal 21 connects a plurality of unit opposing pedestals, for example, adjacent unit opposing pedestals as appropriate, and integrally connects them in the circumferential direction. By being integrally joined to the end face joining plate 3g provided at the end, it can be easily attached to the end face joining plate 3g which will be the end face of the other split formwork main body portion 3B.

With these, the end of the plate mounting seat 20 is used as the end of one split form main body 3A, and the end of the opposing base 21 is used as the end of the other split form main body 3B, and between these ends Furthermore, a slit-shaped gap δ having a width larger than the thickness t (see FIG. 5) of the proximal end portion of the joint forming portion 15A of the joint forming plate member 15 is formed continuously over the entire circumference. possible to form.

As a result, as shown in FIGS. 4 and 5, the edge portions of the outer peripheral surface portion 20b of the plate mounting base 20 and the edge portions of the outer peripheral surface portion 21b of the opposing base 21, which are positioned on both sides of the slit-shaped gap .delta. A pair of face wooden members 20h, 21h are erected from the outer peripheral surface of each of the pair of split form main body portions 3A, 3B by the part, between the opposing surfaces 20i, 21i. It is attached while holding the guide groove 28 .

Here, in the present embodiment, of the pair of face wooden members 20h and 21h, for example, the other face wooden member 21h attached to the facing pedestal 21 is preferably a metallic hardware member having shape-retaining rigidity, for example It is a metal member made of steel, and preferably has a right-angled triangular or right-angled trapezoidal cross-sectional shape with an opposing surface 21i perpendicular to the outer peripheral surface of the split form main body 3B formed by the opposing pedestal 21. ing. The other face wooden member 21h is integrally and firmly joined and fixed to the edge portion of the split form main body portion 3B by the edge portion of the outer peripheral surface portion 21b of the opposing pedestal 21 by a joining means such as welding.

For example, one side wooden member 20h attached to the plate mounting base 20 is the flexible side wooden member 12 having flexibility as described above, and the flexible side wooden member 12 is preferably It is formed using a rubber material. The flexible surface wooden member 12 preferably has a right-angled triangular or right-angled trapezoidal cross-sectional shape with a facing surface 20i perpendicular to the outer peripheral surface of the split form main body 3A by the plate mounting pedestal 20. ing. The flexible surface wooden member 12 is temporarily fixed to the edge portion of the split form main body portion 3A by the edge portion of the outer peripheral surface portion 21b of the opposing pedestal 21 by a bonding means such as an adhesive. ing. As described above, the flexible surface wooden member 12 has a through-hole 12a (see FIG. 5) that continuously penetrates in the circumferential direction of the formwork surface of the split formwork main body 3A, preferably in the shape of a right triangle. Alternatively, it is formed in a state in which it is arranged slightly closer to the bottom surface portion 12b than the center of gravity of the rectangular trapezoidal cross-sectional shape.

A pull wire member 13 preferably made of a wire member is continuously inserted in the circumferential direction through the through holes 12a formed continuously in the circumferential direction of the flexible surface wooden member 12. As shown in FIG. As shown in FIG. 6, the tension wire members 13 continuously inserted through the through-holes 12a extend from the lower ends on both sides of the flexible wooden member 12 to preferably the lower ends on both sides of the form body 3. As shown in FIG. Via the pulley member 13a attached to the part, it is extended so as to be pulled out inside the tunnel lining form 1, and with tension adjusting members 14 preferably made of turnbuckles interposed, both sides are connected to the support leg portions 2b of the portal carriage 2A of the tunnel lining formwork 1, for example, so that the tension adjusting member 14 can adjust the tensile force. .

On the other hand, the flexible surface wooden member 12 is temporarily placed in a state in which the bottom surface portion 12b, which serves as a contact surface with the edge portion of the split form main body portion 3A, for example, protrudes slightly toward the slit-shaped gap δ side. It is fixed (see FIG. 5). Thus, as will be described later, after the plurality of joint forming plate members 15 are attached, tension is adjusted via the tension wire member 13 to allow the tension wire member 13 to have a predetermined size corresponding to the tension. When a tensile force is applied, a stress in the direction Y (see FIG. 5) that tightens the split form main body 3A inward in the radial direction is generated in the flexible face wooden member 12, so that the stress perpendicular to the bottom surface 12b is generated. It is possible to deform the flexible surface wooden member 12 so that the facing surface 20i is inclined toward the joint forming plate member 15 side Z, which is the side that closes the slit-shaped gap δ. As a result, the facing surface 20i of the flexible surface wooden member 12 is brought into close contact with the surface of the joint forming plate member 15 inserted into the guide groove 28, and the flexible member 12 is flexible in a state in which the slit-shaped gap δ is closed. It becomes possible to firmly fix the face wooden member 12 .

Preferably, a plate mounting base 20 and a facing base 21 are attached to the space d between the end faces of the pair of split formwork main bodies 3A and 3B, so that a slit-like gap δ is formed between these ends. After forming over the entire circumference, as shown in FIGS. 1 and 4, each joint forming portion 15A is inserted into the slit-shaped gap δ, and the plurality of joint forming plate members 15 are extended in the circumferential direction. Arrange them in series and attach them individually. The inserted joint forming portion 15A passes through the slit-shaped gap δ and the guide groove 28 formed by the face wooden members 20h and 21h on both sides, so that the outer peripheral portion is positioned outside the tips of the face wooden members 20h and 21h. In the arranged state, it is arranged so as to protrude into the lining space S so as to be able to be pulled out. Each joint forming plate member 15 having the joint forming portion 15A projecting into the lining space S is attached to the form body 3 by supporting the inward projecting grip portion 15B on the plate mounting pedestal 20. be done.

The operation of inserting the plurality of joint forming plate members 15 into the slit-shaped gap δ is preferably performed by inserting the plate mounting pedestal 20 by a plurality of unit mounting pedestals provided corresponding to the number of the joint forming plate members 15. The surface of the joint forming plate member 15 facing the mounting surface 20a is pressed against the guide projection 24a (see FIG. 4) protruding from the surface of the mounting surface 20a. It is possible to smoothly insert the plate member 15 while stabilizing the direction of insertion.

Further, a plurality of joint forming plate members 15 are inserted into the slit-shaped gaps .delta. After matching with the pedestal side pin insertion holes 23a formed in the mounting surface portion 20a, as described above, the pin members 26 are inserted into the matching pin insertion holes 16a, 23a, thereby forming the respective joint forming plates. The member 15 can be supported and attached to the plate attachment pedestal 20 in a state in which the joint forming portion 15A protrudes into the lining space S through the slit-shaped gap δ.

In this embodiment, in addition to inserting the pin members 26 into the matching pin insertion holes 16a and 23a, as described above, the surface of each joint forming plate member 15 facing the plate mounting pedestal 20 is The fixing bolt 25b is rotatably supported on the back side of the mounting surface portion 20a of the plate mounting pedestal 20 in the notch hole 18a of the overhanging fastening piece 18 provided so as to project from the inner peripheral end of the fixing bolt 25b. is fastened using the nut member 25c. As a result, each joint forming plate member 15 can be mounted on the plate mounting base 20 in a more stable state.

As described above, the plate mounting pedestal 20 and the facing pedestal 21 of the joint forming unit 40 are attached to the space d between the pair of split form main bodies 3A and 3B, and a plurality of By inserting the joint portion forming portions 15A of the joint portion forming plate members 15 respectively, the joint portion forming plate members 15 are continuously arranged in the circumferential direction and attached, and then the tunnel T covered by the primary lining 5 is formed. Concrete is placed in the lining space S, which is a space for placing concrete, formed between the inner peripheral surface and the formwork surface formed by the outer peripheral portion of the formwork main body 3 of the formwork for tunnel lining 1. Then, the work of constructing the tunnel lining concrete 4 is performed. In the present embodiment, as shown in FIGS. 2 and 3, the work of constructing the tunnel lining concrete 4 consists of concrete that is pumped from two concrete pumps 30 via pumping pipes 31 extending from each of the concrete pumps 30. It can be carried out by placing while simultaneously supplying to the working space S.

In this embodiment, the two concrete pumps 30 are arranged in front and rear of the tunnel T in the excavation direction X with the tunnel lining formwork 1 carried into the tunnel T interposed therebetween. Concrete is charged from each concrete mixer truck 32 into the hopper portion of the concrete pump 30 . Here, pressure-feeding pipes 31 extend from the two front and rear concrete pumps 30, respectively. 31 to the lining space S and are simultaneously pumped and supplied. Thus, by using two systems of the concrete pump 30 and pressure-feeding pipe 31, the progress of the process for forming the tunnel lining concrete 4 can be effectively accelerated.

Two systems of pumping pipes 31 extending from the two concrete pumps 30 are a main pipe 31a extending toward the inside of the tunnel lining formwork 1, and a main pipe 31a extending in the width direction of the tunnel T via a rotary valve 29 from the main pipe 31a. It is configured including left and right branch pipes 31b branched on both sides. Here, each of the branch pipes 31b includes a plurality of piece pipes made up of straight pipes, curved pipes, etc., having different lengths. are arranged to be connected to each other. Further, by rearranging these piece pipes, the branch pipe 31b is preferably formed at the rear end of each of the split formwork main bodies 3A and 3B, which are divided into two parts of the formwork main body 3, in the excavation direction X. Alternatively, the lower press-fit connection port 11a can be switched to the upper press-fit connection port 11b, or the upper press-fit connection port 11b can be switched to the zenith press-fit connection port 27 to place concrete. is now possible.

In the present embodiment, when the tunnel lining concrete 4 is formed by hardening the concrete placed in the lining space S by the work of constructing the tunnel lining concrete 4 described above, a plurality of joint forming plate members 15 are pulled out from the lining space S to the inside of the form body 3 to form an induced joint.

According to the mounting structure 10 of the joint forming plate member of the present embodiment having the above-described configuration, for example, when the split form main bodies 3A and 3B are distorted during assembly of the form main body 3, slit-like The gap between the gap δ or the guide groove 28 and the inserted joint forming plate member 15 is closed, and the paste or mortar in the concrete placed in the lining space S is It is possible to effectively prevent the slag from flowing out to the inside of the split formwork main bodies 3A and 3B.

That is, according to the present embodiment, one of the pair of side wooden members 20h, 21h arranged to stand from the outer peripheral surface of the end edge of each of the pair of split formwork main bodies 3A, 3B As at least one, for example, the face wooden member 20h attached to the split form main body 3A is a flexible face wooden member 12 having flexibility. A tension wire member 13 is continuously inserted through the through hole 12a which is continuous in the direction, and both ends of the tension wire member 13 extend from the end of the flexible wooden member 12 to the tunnel lining. For example, the support legs 2b of the portal carriage 2A of the tunnel lining form 1 are connected to each other with the tension adjusting member 14 interposed therebetween. The tension wire member 13 is stretched in a state in which the tension can be adjusted by the tension adjusting member 14 .

Therefore, according to the present embodiment, for example, after the joint forming plate member is attached, the tensile linear member 13 is adjusted by adjusting the tension by the tension adjusting member 14 before concrete is placed in the lining space S. By applying a predetermined tensile force to the flexible surface wooden member 12, it is possible to deform the flexible surface wooden member 12 so that the facing surface 20i is inclined toward the joint forming plate member 15 side. The facing surface 20i of the member 12 is firmly adhered to the surface of the joint forming plate member 15 inserted into the guide groove 28, and the flexible surface wooden member 12 is placed in a state in which the slit-shaped gap δ is closed. It becomes possible to fix. As a result, the gap between the inserted joint forming plate member 15 and the inserted joint forming plate member 15 is closed, and the paste or mortar in the concrete placed in the lining space S is removed as slag on the main body of the split form. It becomes possible to effectively avoid flowing out to the inside of the portions 3A and 3B.

It should be noted that the present invention is not limited to the above embodiments, and various modifications are possible. For example, the flexible face wood does not necessarily have to be formed using a rubber material, and can be formed using various other flexibly deformable members. The tensile wire member does not necessarily have to be a wire member, and may be a tensile wire member made of various other tensile materials such as piano wire. The tension adjusting member does not necessarily have to consist of a turnbuckle, and may be other various tension adjusting members using a jack or the like.

1 Tunnel lining form 2 Mounting frame 3 Form body 3A, 3B Split form body 4 Tunnel lining concrete (lining concrete)
10 Mounting structure of joint forming plate member 12 Flexible surface wooden member 12a Penetrating hole 13 Pulling wire member 14 Tension adjusting member 15 Joint forming plate member 15A Joint forming portion 15B Inner protruding grip portion 20 Plate mounting Pedestal 20b Peripheral surface portion 20h Surface wooden member 20i Opposing surface 21 Opposing pedestal 21b Peripheral surface portion 21h Surface wooden member 21i Opposing surface δ Slit-shaped gap S Lining space T Tunnel X Tunnel excavation direction (axial direction of tunnel lining formwork )

Claims (5)

In the mountain tunnel construction method, it is attached to the tunnel lining form that is installed when constructing the tunnel lining concrete that covers the inner wall surface of the tunnel so that it can be pulled out at the intermediate part in the axial direction of the tunnel lining form. A mounting structure for a joint forming plate member for forming an induced joint in a constructed tunnel lining concrete,
The tunnel lining formwork includes a pedestal that is movable in the tunnel excavation direction, and a formwork main body that is supported by the pedestal and forms a lining space between itself and the inner wall surface of the tunnel. cage,
The formwork main body is composed of a pair of split formwork main bodies divided in the tunnel excavation direction, and a slit-like slit is provided between the adjacent ends of the pair of split formwork main bodies. A gap is formed continuously over the entire circumference, and a plurality of the joint forming plate members are inserted into the slit-shaped gaps, and the inserted joint forming plate members extend outward. In a state in which the joint forming portion on the peripheral side protrudes into the lining space, the inner protruding gripping portion on the inner peripheral side is fixed to the main body of the split formwork, and attached so as to be continuously arranged in the circumferential direction. and
A pair of face wooden members stand upright from the outer peripheral surfaces of the edge portions of the pair of main body portions located on both sides of the slit-shaped gap, and hold the guide groove between the opposing surfaces. is fixed along the edge in a state,
Each of the joint forming plate members is inserted into the slit-shaped gap and the guide groove formed by the face wooden members on both sides so that the outer peripheral portion of the joint forming portion is outside the tip of the face wooden member. is attached to the formwork main body so as to be able to be pulled out,
At least one of the face wooden members on both sides is a flexible face wooden member having flexibility. A tension wire member is continuously inserted through the through hole, and both ends of the tension wire member extend from the end of the flexible face wooden member to the inside of the tunnel lining form. extending and connected to the tension adjusting member,
The flexible face plate member is deformed so as to come into close contact with the joint forming plate member inserted into the guide groove when a tensile force is applied to the tensile wire member by the tension adjusting member. Mounting structure for joint forming plate members. 2. The joint according to claim 1, wherein the face wooden member has a right-angled triangular or right-angled trapezoidal cross-sectional shape with the facing surface perpendicular or substantially perpendicular to the outer peripheral surface of the split formwork main body. Attachment structure of the part-forming plate member. 3. The mounting structure of a joint forming plate member according to claim 1, wherein said flexible panel member is formed using a rubber material. The joint forming plate member mounting structure according to any one of claims 1 to 3, wherein the tensile wire-shaped member comprises a wire member. The joint forming plate member mounting structure according to any one of claims 1 to 4, wherein the tension adjusting member comprises a turnbuckle.

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