JP5060417B2 - Segment formwork - Google Patents

Description

  The present invention relates to a segment formwork.

In recent years, shield tunnels tend to be deeper and larger.
As the shield tunnel becomes deeper, the compressive force applied to the segment ring due to earth pressure, groundwater pressure, etc. becomes more prominent, increasing the burden on the segment joint surface. In addition, the segment that has become larger as the tunnel cross-section has a larger diameter may be damaged at the corners during transportation or assembly.

  Further, as the shield tunnel becomes deeper and has a larger cross-section, the amount of compression due to jack propulsion during construction may be dominant at the axial end of the segment.

  Therefore, for example, as shown in Patent Document 1, a segment in which a joint surface (corner portion) of a segment is reinforced by disposing a high-strength end surface member made of a fiber reinforcing material at a joint portion between the segments. As a method, the general part and the end face member were integrally formed by placing concrete of the main body part (the part other than the end face member) of the segment in a state in which the end face member manufactured in advance was disposed on the mold. A method of manufacturing a segment is disclosed.

  Further, in Patent Document 2, as a method of manufacturing a segment reinforced by disposing a high-strength end surface member made of a fiber reinforcing material on an end surface on which the jack propulsive force of the segment acts, A method of manufacturing a segment in which a general part and an end face member are integrally formed by disposing an end face member on an upper surface of the cast concrete after placing the general part of concrete is disclosed.

  However, the segment manufacturing method described in Patent Document 1 or Patent Document 2 requires a separate process for manufacturing the end face member in advance.

  On the other hand, Patent Document 3 discloses a method of manufacturing a segment having a two-layer structure by placing different concrete on the inner peripheral side and the outer peripheral side.

  In such a segment manufacturing method, concrete is placed on the inner peripheral side and the outer peripheral side in a state where a removable partition plate is previously installed in the mold, and the partition plate is removed from the mold from the side of the mold. A two-layer segment is formed.

JP 2005-194743 A Japanese Patent Laying-Open No. 2005-076305 JP 2007-296803 A

  However, in the invention described in Patent Document 3, since a gap is formed on the side surface of the mold when the partition plate is pulled out sideways, the concrete flows out from the gap. Therefore, it was necessary to prevent the concrete from flowing out by stopping the end of the partition plate at the inner surface of the mold without completely pulling out the partition plate or by inserting a plug into the gap formed by pulling out the partition plate. .

However, when the partition plate is fastened to the inner surface of the mold without being completely pulled out, it takes time to fix the partition plate, and it is necessary to prepare a fixing jig separately.
In addition, when plugs are inserted, it takes time to increase the cost of manufacturing the plugs separately and to insert the plugs immediately after the partition plate is pulled out.

  The object of the present invention is to solve the above-mentioned problems, and for a segment that can be manufactured easily and inexpensively with a high quality segment including parts formed of materials of different strengths. The challenge is to propose a formwork.

  In order to solve the above-mentioned problems, the present invention provides a segment form for producing a segment having an arc-shaped cross section having a general part made of a concrete material and an end surface part made of a concrete material having a different composition from the general part. A mold body that is laid flat, an upper frame that covers an opening on an upper surface of the mold body, and a partition that partitions a boundary between the general part and the end face part, The frame part has a fixed plate fixed on the mold body so as to cover the upper surface of the general part, and a slide plate disposed on the mold body so as to cover the upper surface of the end surface part. The partition portion can be pulled upward from a gap provided between the fixed plate and the slide plate, and the slide plate is slidable toward the fixed plate, and the partition portion After pulling out the slide plate It is characterized in that closing the gap by id.

  According to such a form for a segment, it is possible to prevent the material from flowing out from the gap formed by pulling out the partitioning portion only by sliding the slide plate when manufacturing the segment in which the material having different strength is cast. Because it can, it is excellent in workability. Further, since a special mechanism is not required for preventing the outflow of material, the segment mold is simple and inexpensive.

  In addition, if the partition portion is composed of a plurality of partition plates stacked in the plate thickness direction and can be pulled out one by one, it is formed by pulling out the partition portion (partition plate). Since the gap to be formed can be narrowed, the outflow of the material can be more effectively prevented.

  In addition, if the slide plate is biased by the elastic member in the direction toward the fixed plate, the partition portion is pulled out, and the slide plate slides to automatically remove the gap formed by pulling out the partition portion. It is excellent in workability.

  According to the segment form of the present invention, it is possible to manufacture a segment including a portion formed of a material having a different strength with high quality in a simple and inexpensive manner.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings.
In this embodiment, the shield by as shown in FIG. 1 (a), to form a segmented ring S _R of a ring by combining a plurality tunnel circumferential direction, a plurality connecting the segment ring S _R in the tunnel axis The segment mold 1 for manufacturing the segment S forming the outer shell of the tunnel T will be described.

  As shown in FIG. 1 (b), the segment S is a rebar R concrete member formed in a circular arc shape in cross section, and includes a general part S1 at the center portion in the tunnel circumferential direction made of a hardened body of high-fluidity concrete, It is comprised by the end surface part S2 which consists of a hardening body of the fiber reinforced cementitious concrete each formed in the direction both ends.

  The concrete material constituting the general part S1 and the end face part S2 of the segment S is not limited to the above-mentioned ones. For example, high-strength concrete or ordinary concrete may be used. Select from the above and use it. In addition, the concrete material used by general part S1 and end surface part S2 should just be comprised by the mixing | blending different according to the use.

As a segment mold 1 for manufacturing such a segment S, as shown in FIG. 2, a flat mold body 2, an upper frame portion 3 covering an opening on the upper surface of the mold main body 2, and a general part S 1 And the partition part 4 which partitions the boundary part of the end surface part S2 are used.
Note that the flat placement means that the mold body 2 is arranged such that the surface of the segment S that is the inner peripheral surface of the tunnel is down and the surface that is the outer peripheral surface of the tunnel is up.

The mold body 2 is a steel box-like body having an open upper surface, and has an arc shape corresponding to the cross-sectional shape of the tunnel T (segment S).
The mold body 2 is composed of a bottom plate portion 21 made of an arc-shaped plate-like member and a side wall portion 22 erected on the periphery of the bottom plate portion 21. The bottom plate portion 21 forms a circular arc surface that becomes the inner peripheral surface of the tunnel.

A locking portion 23 is formed on the upper end of the side wall portion 22 in the tunnel circumferential direction. The locking portion 23 of the present embodiment includes a bolt projecting from the upper end surface of the side wall portion 22.
In addition, the structure, arrangement | positioning, number, etc. of the latching | locking part 23 are not limited, It is possible to set suitably.

  The upper frame portion 3 is disposed on the mold body 2 so as to cover the fixing plate 31 fixed on the mold body 2 so as to cover the upper surface of the general portion S1 of the segment S and the upper surface of the end surface portion S2. The slide plate 32 is provided.

The fixed plate 31 is a plate-like member fixed so as to cover the center upper surface of the mold body 2 in the circumferential direction of the tunnel, and is disposed between the left and right partition portions 4 and 4. In the center of the fixed plate 31, an opening (placement port 31a) for placing concrete is formed.
In the present embodiment, the fixed plate 31 is configured by combining a plurality of plate materials.

  In the case where the placement hole 22a (see FIG. 4) is formed in the fixing plate 31 or the side wall portion 22 in the circumferential direction of the tunnel of the mold body 2, and the concrete is placed via a pump, 31a may be omitted.

  The slide plate 32 is a plate-like member disposed so as to cover the upper surface of the end portion of the mold body 2, and is disposed on the end portion side (segment joint side) with respect to the partition portion 4. A long hole 32 a and a slit 32 b are formed in the slide plate 32 in accordance with the position of the locking portion 23 formed in the mold body 2.

The long hole 32a is formed long along the circumferential direction of the tunnel so that the slide plate 32 can slide in the circumferential direction of the tunnel on the upper surface of the mold body 2. Similarly, the slit 32b is formed in a groove shape along the tunnel circumferential direction with an opening at the partition 4 side tip in the tunnel circumferential direction.
In order to suppress the slide range of the slide plate 32, it is desirable to form at least one long hole 32a. However, if the slide range can be suppressed only by the slit 32b, the long hole 32a is omitted. It is also possible.

  The slide plate 32 is slidably disposed toward the fixed plate 31 on the upper surface of the mold body 2 with the locking portion 23 inserted through the long hole 32a and the slits 32b and 32b. The slide plate 32 slides toward the fixed plate 31, thereby closing a gap between the fixed plate 31 and the slide 32 formed by pulling out the partition portion 4 from the mold body 2.

  The partition 4 is disposed in a gap provided between the fixed plate 31 and the slide plate 32 and can be pulled upward.

  The partition portion 4 includes a plurality of (three in the present embodiment) partition plates 41 stacked in the plate thickness direction (tunnel circumferential direction), and is arranged so that each partition plate 41 can be pulled out one by one. Yes.

  The partition plate 41 is made of a steel plate, and is arranged so that the upper end protrudes from the upper surface of the mold body 2 and the lower end abuts the bottom plate 21 of the mold body 2.

In addition, the material which comprises the partition plate 41 (partition part 4) will not be limited if it has a predetermined | prescribed intensity | strength, For example, it selects from well-known materials, such as comprising by a wooden member, and forms. Is possible.
Further, the partition plate 41 may have a multilayer structure in which a plurality of members are stacked and integrated, for example, a rubber plate is sandwiched between two steel plates.

  Further, by installing an outflow prevention material (not shown) such as natural rubber, synthetic rubber, urethane, or the like on the bottom end face or side end face of the partition plate 41 (partition section 4), the partition section 4 and the mold body 2 are separated from each other. The concrete may be prevented from flowing out of the gap.

  A through hole 42 used as a handle when the partition plate 41 is arranged on the mold body 2 and when being pulled out from the mold body 2 is formed at the upper end of the partition plate 41. Note that the number, arrangement, shape, and the like of the through holes 42 are not limited and can be set as appropriate. Further, the handle need not be a through hole and can be set as appropriate. Furthermore, when using a lifting machine such as a crane, the handle may be omitted by forming a member according to the configuration of the lifting machine.

  Each partition plate 41 is formed with a slit 43 according to the position of the reinforcing bar R arranged in the segment S. Further, the slit 43 is shielded by a slit portion outflow prevention material 44 made of natural rubber, synthetic rubber, urethane or the like in order to prevent the concrete from flowing out.

The slit part outflow prevention member 44 according to the present embodiment is configured by arranging the long sides of two vertically long members in a state of abutting each other. The reinforcing bar R is inserted through this butted portion.
In addition, the structure of the slit part outflow prevention material 44 is not limited, and can be set as appropriate.

  Next, a segment manufacturing method using the segment mold 1 according to this embodiment will be described with reference to FIG.

  The segment manufacturing method according to the present embodiment includes an end face concrete placing process, a general concrete placing process, a partition pulling process, and a curing process.

As shown in FIG. 3A, the end surface portion concrete placing step is performed in a state in which the partition portion 4 is arranged on the mold body 2 (the portion corresponding to the end surface portion S <b> 2 of the mold body 2). This is a step of placing concrete (fiber reinforced cement concrete) on both ends.
At this time, the slide plate 32 is disposed on the upper surface of the mold body 2 with a gap between the slide plate 32 and the partition portion 4 that allows concrete to be placed.

  In the mold body 2, the reinforcing bars R of the segments S are arranged in advance at a predetermined pitch, and the partition part 4 is arranged in a state where the reinforcing bars R are inserted through the slits 43.

  Then, when the concrete placement of the end surface portion S2 is finished, the slide plate 32 is slid in the direction of the partition portion 4 to shield the gap between the slide plate 32 and the partition portion 4 (see FIG. 3B).

  In the general part concrete placing process, after the concrete placement of the end face part S2 in the end face part concrete placing process is completed, as shown in FIG. 3 (b), from the placement port 31a to the part corresponding to the general part S1. This is a process of placing high fluidity concrete.

  Since the slit 43 of the slide plate 32 is shielded by the slit portion outflow prevention material 44 except for the portion where the rebar R is inserted, the high-fluidity concrete of the general portion S1 and the fiber-reinforced cement-based concrete of the end surface portion S2 But it doesn't mix at this stage.

  In addition, the order of an end surface part concrete placement process and a general part concrete placement process is not limited, You may implement an end face part concrete placement process after a general part concrete placement process.

  As shown in FIG. 3 (c), the partition portion pulling step is performed by separating the partition portion 4 from the mold body 2 in which the high-fluidity concrete and the fiber-reinforced cement-based concrete of the general portion S1 and the end surface portions S2 and S2 are placed. Is a process of pulling out.

The partition 4 is pulled out by pulling out the partition plates 41 one by one from the partition plate 41 provided on the slide plate 32 side. By pulling out one partition plate 41, a gap is formed between the remaining partition plate 41 (the fixed plate 31 when the last partition plate 41 is pulled out) and the slide plate 32, so that the slide plate 32 is slid at any time. And shield the gap.
The slide plate 32 shields the gap formed by pulling out the partition portion 4, thereby preventing the concrete (high-fluidity concrete or fiber-reinforced cement concrete) from flowing out from this gap.

In addition, when the high fluidity concrete of main part S1 flows down to end face part S2 side by pulling out partition part 4, and the placement upper surface of the central part of main part S1 becomes low, it is suitably from placement mouth 31a. The high fluidity concrete is placed (supplemented) so that the main body S1 can secure a predetermined thickness.
Moreover, high fluidity concrete or fiber reinforced cementitious concrete shall perform vibration compaction as needed.

As shown in FIG. 3D, the curing process is a process of curing concrete in a state where the partition portion 4 is pulled out and the slide plate 32 is brought into close contact with the fixed plate 31.
By curing in a state where the main body S1 and the end surface S2 are in close contact with each other, a segment S (see FIG. 1B) in which the main body S1 and the end surface S2 are integrated is formed.

  After curing, the fixed plate 31 and the slide plate 32 are removed from the mold body 2 and the segment S is taken out.

  As mentioned above, according to the formwork for segments of this embodiment, after placing concrete of general part S1 and end face part S2, the boundary surface of concrete of different intensity is maintained only by extracting partition part 4 Thus, since it is integrally formed, a high-quality segment S can be easily manufactured.

Since the gap formed by pulling out the partition portion 4 can be easily shielded by simply sliding the slide plate 32 and the concrete can be prevented from flowing out, the high-quality segment S can be easily manufactured.
Moreover, since the partition part 4 is pulled out upward, the gap formed by pulling out the partition part 4 is opened upward, and the concrete flows out as compared with the case where the partition member is pulled out from the conventional side. Hateful.

  By manufacturing the general part S1 and the end face part S2 at the same time, it is possible to reduce the time and labor required for manufacturing the segment S, and it is possible to reduce the manufacturing cost.

The segment mold 1 can be manufactured at low cost because of its simple configuration.
Since the slide plate 32 slides along the locking portion 23, the slide plate 32 is prevented from being displaced, and the workability is excellent.

  It is possible to minimize the size of the gap formed by pulling out the partition portion 4 by configuring the partition portion 4 by laminating a plurality of partition plates 41, 41,. It is more effective in preventing leakage.

  In the slit 43 of the partition part 4, since the slit part outflow prevention material 44 is disposed, the concrete is prevented from being mixed with each other, and the boundary surface between the concretes having different strengths (mixing) is maintained. High quality segments can be produced.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and it goes without saying that the above-described constituent elements can be appropriately changed in design without departing from the spirit of the present invention.
For example, in the above-described embodiment, the slide plate 32 is slid in a state where the locking portion 23 is inserted into the long hole 32a and the slit 32b formed in the slide plate 32. Grooves or ridges may be formed on the slide plate 32 along the circumferential direction of the tunnel, respectively, and the configuration is not limited. It is possible to easily slide the slide plate 32 by sliding in a state where the grooves and the protrusions are engaged with each other.

The slide plate 32 is urged in a direction toward the fixed plate 31 by an elastic member (not shown) such as a spring, for example, so that the slide plate automatically slides in the direction of the fixed plate 31 at the same time as the partition portion 4 is pulled out. It is good also as a structure.
The slide plate 32 may be slid manually or mechanically.

In the said embodiment, the segment formwork for manufacturing the segment S by which the joint surface of the segments S was reinforced by placing the fiber reinforced cement concrete in the end surface part of the tunnel circumferential direction of the segment S was demonstrated. segment but, as a segment mold frame 1 'shown in FIG. 4, by disposing the partition section 4 for dividing the mold body 2 at the tunnel axis, the joint surfaces of the segment ring S _R together are reinforced It is good also as what forms.
In the above embodiment, the end surface portion S2 is formed by placing concrete having different blending (strength) at both ends of the segment S. However, the end surface portion S2 may be formed only on one side.

  The concrete placement method is not limited to placement from an opening such as the placement port 31a or the gap between the partition portion 4 and the slide plate 32, and can be appropriately performed by a known means. For example, as shown in FIG. 4, the concrete pumped through a concrete pump may be driven from a placement hole 22 a formed at a predetermined position of the mold body 2 or the upper frame 3.

(A) is a front view of the segment ring which concerns on suitable embodiment of this invention, (b) is a perspective view of the segment. It is a perspective view which shows the formwork for segments which concerns on suitable embodiment of this invention. (A)-(d) is a perspective view which shows each process of the manufacturing method of the segment which uses the mold for segments shown in FIG. It is a perspective view which shows the modification of the mold for segments shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Formwork for segments 2 Formwork body 3 Upper frame part 31 Fixed plate 32 Slide plate 4 Partition part 41 Partition plate S Segment S _R Segment ring S1 General part S2 End face part T Tunnel

Claims (3)

A segment mold for producing a segment having an arc-shaped cross section having a general part made of a concrete material and an end face part made of a concrete material having a different composition from the general part,
A formwork body placed flat,
An upper frame portion covering the opening on the upper surface of the mold body;
A partition part that partitions a boundary part between the general part and the end face part,
A fixing plate fixed on the mold body so that the upper frame portion covers the upper surface of the general portion; and a slide plate disposed on the mold body so as to cover the upper surface of the end surface portion. Have
The partition portion can be pulled upward from a gap provided between the fixed plate and the slide plate,
The slide plate is slidable toward the fixed plate;
A segment mold, wherein the gap is closed by sliding the slide plate after the partition portion is pulled out.   The segment mold according to claim 1, wherein the partition portion includes a plurality of partition plates stacked in a plate thickness direction, and is configured such that the partition plates can be pulled out one by one. frame.   The segment mold according to claim 1 or 2, wherein the slide plate is urged in a direction toward the fixed plate by an elastic member.

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