JP7029505B1 - Formwork unit and how to build the formwork - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substantially circular formwork unit and a method for constructing a formwork, which can be quickly installed and have high rigidity. SOLUTION: This is a formwork unit FU of a substantially cylindrical or substantially cylindrical reinforced concrete structure, and the formwork unit FU is a liner plate 71 which is a weir plate formed in a substantially cylindrical piece shape, and a liner plate 71. An arc-shaped upper reinforcing ring 72 attached to the upper edge, an upper reinforcing ring 72 having a convex portion protruding upward, and an arc-shaped lower reinforcing ring 74 attached to the lower edge of the liner plate 71. , A lower reinforcing ring 74 having a concave portion that fits into the convex portion. [Selection diagram] FIG. 11

Description

Patent Law Article 30 Paragraph 2 Applicable Construction on December 12, 1st year under the site name "Hokuriku Shinkansen Fukui Bridge JV"

INDUSTRIAL APPLICABILITY The present invention has a cylindrical, elliptical pillar, or substantially circular pillar including a pillar having an oval cross section, or a cylindrical, elliptical cylinder, or a cylinder having an oval cross section having the contour of an oval cylinder. It relates to a mold unit arranged in a cylindrical reinforced concrete structure and a method of constructing a mold.

Formwork is generally used when constructing concrete structures. On the other hand, there was no large-diameter formwork that could withstand the lateral pressure of high-fluidity concrete with a maximum concrete casting height of 10 m at a time. When placing high-fluidity concrete with such height, it is conceivable to use segment steel with high rigidity and connect the segments with a large number of bolts. In addition, for example, Patent Document 1 discloses a method for forming a deep foundation foundation using a liner plate as an inner formwork instead of a segment.

Japanese Unexamined Patent Publication No. 10-1944

However, in recent years, there has been a demand for shortening the construction period, but it has been difficult to shorten the construction period because the method of connecting the segments with a large number of bolts requires the work at the skeleton construction site. Further, when the formwork is constructed only with the liner plate, the rigidity of the formwork is insufficient, so that the accuracy of the structure cannot be ensured.

Therefore, an object of the present invention is to provide a substantially circular formwork that can be quickly installed and has high rigidity.

In order to achieve the above object, the frame unit of the present invention has a cylindrical shape, an elliptical pillar shape, a substantially circular pillar including a pillar having an oval cross section, or a cylindrical shape, an elliptical cylinder shape, or a flat shape. It is a form unit of a substantially cylindrical reinforced concrete structure having the outline of an oval-shaped cylinder in cross section, and has a weir plate configured in a substantially cylindrical piece shape and an arc shape attached to the upper edge of the weir plate. An upper reinforcing ring having a convex portion protruding upward, and an arc-shaped lower reinforcing ring attached to the lower edge of the dam, having a concave portion fitted to the convex portion. It is equipped with a lower reinforcing ring.

Further, the method for constructing a formwork of the present invention is a method for constructing a formwork using the above-mentioned formwork unit, in which the process of manufacturing the formwork unit and the formwork unit are connected in the circumferential direction. The step of forming the substantially circular formwork, the step of lifting the substantially circular formwork using the suspension holes, and the step of fitting the concave portion of the lower reinforcing ring to the convex portion of the upper reinforcing ring to form the substantially circular form. It includes a step of superimposing the formwork and a step of connecting the superposed substantially circular formwork in the vertical direction.

As described above, the formwork unit of the present invention includes a weir, an upper reinforcing ring having a convex portion protruding upward, and a lower reinforcing ring having a concave portion fitted to the convex portion. Therefore, by using the formwork unit, it becomes a substantially circular formwork that can be installed quickly and has high rigidity.

Further, the method for constructing the formwork of the present invention includes a step of manufacturing the formwork unit, a step of connecting the formwork units in the circumferential direction to form a substantially circular formwork, and a substantially circular formwork using a hanging hole. The process of lifting the upper reinforcement ring, the process of fitting the concave portion of the lower reinforcement ring to the convex part of the upper reinforcement ring, and the process of overlapping the substantially circular formwork, and the process of connecting the overlapped substantially circular formwork in the vertical direction. I have. Therefore, by using the formwork construction method, it is possible to construct a substantially circular formwork that can be installed quickly and has high rigidity.

It is a flowchart which shows the whole process which constructs a caisson foundation. It is sectional drawing explaining the whole structure of a caisson foundation. It is a top view of a reinforcing bar unit. It is a side view of a reinforcing bar unit. It is a front view of a reinforcing bar unit. It is a plan view of the lower template. It is explanatory drawing of the above template. (A) is a plan view, and (b) is a side view. It is an enlarged view of the connection part of the upper and lower reinforcing bar units. It is an enlarged view of the connection point of the left and right reinforcing bar units. It is a side view of a formwork block. It is a side view of a formwork unit. It is a top view of the dam of the formwork unit. It is a top view of the reinforcing ring of a formwork unit. It is sectional drawing of the formwork unit. (A) is an overall view, and (b) is an enlarged view. It is explanatory drawing of the rod material for alignment. (A) is a cross-sectional view, and (b) is a front view. It is a detailed view of the upper and lower connection plates. (A) is a cross-sectional view, and (b) is a front view. It is an enlarged action diagram in the vicinity of the fitting portion of the concave portion and the convex portion. (A) is a diagram when the upper formwork unit FU is displaced outward from the lower formwork unit FU, and (b) is a diagram in which the upper formwork unit FU is displaced inward from the lower formwork unit FU. The figure in the case of (c) is a figure of the final state in which the positional deviation in the radial direction is corrected and the top and bottom pass through.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the components described in the following examples are examples, and the technical scope of the present invention is not limited to them. In the following, the whole process will be described in Example 1, the reinforcing bar unit (U) will be described in Example 2, and the formwork unit (FU) will be described in Example 3.

(Overall process)
First, using the flowchart of FIG. 1 and the sectional view of FIG. 2, a method for assembling the reinforcing bar of the present invention and a method for constructing a cylindrical or cylindrical reinforced concrete structure including a method for constructing a formwork will be described. do. In the following, the case of constructing a cylindrical RC structure inside a circular shaft (S) constructed by a steel open caisson method, using the caisson foundation C having a circular cross section (cylindrical cross section) as an example, has high rigidity. An example of applying a reinforcing bar unit (a method for rapidly assembling a circular or cylindrical RC structure) and a high-rigidity formwork (a method for rapidly assembling a circular formwork) will be described.

In advance, a columnar space is constructed by a press-fitting caisson method using a steel split assembly type (temporary) retaining wall S. That is, the reinforcing bar unit U and the formwork unit FU of this embodiment have a cylindrical reinforced concrete (RC) structure in the internal space of the circular retaining wall (cum-formwork) S already constructed on the outside. Used when building things.

(Step S1)
First, the gantry frame 10 is constructed in a temporary yard on the ground that is provided separately from the original position. Next, a plurality of main bars 41, ..., Reinforcing bars 42, ..., Shear reinforcing bars (not shown), ... Are attached to the gantry frame 10 by a binding wire or the like to construct a reinforcing bar unit U. ..

The reinforcing bar unit U is divided by 10 m in the vertical direction (cylindrical axis direction) and divided into four by a central angle of 90 degrees in the circumferential direction. The reinforcing bar unit U can be created for 360 degrees (4 units) by parallel work.

(Step S2)
Next, the inner scaffolding required for the reinforcing bar connection work is installed (the second and higher stages are raised). In this embodiment, a box-shaped floating body filled with urethane foam is connected, and then a frame scaffold is assembled and installed in a substantially circular shape on the box-shaped floating body. When raising the scaffolding, water is injected into the inside of the inner formwork to raise the water level, thereby raising the scaffolding.

(Step S3)
Next, after assembling each reinforcing bar unit U (including the preparation of the mechanical joint) on the ground using the gantry frame 10, the reinforcing bar units U are suspended one by one.

(Step S4)
Next, the adjacent reinforcing bar units U and U are connected to each other, and the reinforcing bars (41 and 42) are also connected in the vertical direction and the circumferential direction.

(Step S5)
Next, the formwork unit FU is installed. The mold is divided into about 1.7 m (three steps of liner plate + upper and lower reinforcing rings) in the vertical direction (cylindrical axis direction), and is divided into four in the circumferential direction. Assemble the four pieces near the installation location and hang them one by one as a circular mold unit FU, and connect them up and down.

(Step S6)
Next, a reinforcing bar spacer is installed between the formwork unit FU, which is an inner formwork, and the reinforcing bar unit U (only on the front side). The reinforcing bar spacer is installed once on the reinforcing bar near the reinforcing ring of the formwork unit FU after installing the formwork unit FU having a height of about 1.7 m for two stages to secure the cover between the reinforcing ring and the reinforcing bar. The reinforcing bar spacer has, for example, a mortar-made top having a rounded conical shape, and two steel plates for sandwiching the reinforcing bar are projected from the bottom surface. When installing, the top of the cone is in contact with the formwork to ensure the required cover.

(Step S7)
Next, the upper formwork unit FU is installed, and the scaffolding is extended and fixed.

(Step S8)
Next, concrete for one lift of the formwork and a height of 10 m is placed at one time. High-fluidity concrete is used as the concrete because it is difficult to compact the concrete by allowing the vibration of the vibrator to reach 10 m below.

(Step S9)
Finally, for example, the day after the concrete is placed, the latency on the upper surface of the concrete is removed and the construction cycle of the next lift is started (returning to step S1).

As mentioned above, in this method, in each lift, "scaffolding installation or height adjustment", "high-rigidity reinforcing bar installation", "formwork unit installation", "reinforcing bar spacer installation", "concrete" The construction is repeated in the order of "casting".

(Structure of reinforcing bar unit U)
Here, the configuration of the reinforcing bar unit U will be described with reference to FIGS. 3 to 5. In the reinforcing bar unit U, a plurality of main reinforcing bars 41, ..., A plurality of band reinforcing bars 42, ..., And a plurality of shear reinforcing bars (not shown), ... Is attached and configured. As shown in FIGS. 3 to 5, the gantry frame 10 is constructed as a highly rigid frame using equilateral angle steel (angle). The gantry frame 10 has arc-shaped reinforcing steel materials 11 and 12 in two upper and lower stages, and a vertical member 13 to which an overhang (shelf member 13a) on which the reinforcing bars are placed at intervals in the height direction is attached. It is configured by installing 5 inside and outside in the direction.

More specifically, the gantry frame 10 includes an inner arc-shaped (small arc) auxiliary steel material 11, an outer arc-shaped (large arc) auxiliary steel material 12, and upper and lower inner auxiliary steel materials 11. The five vertical members 13 connecting 11 and the five vertical members 13 connecting the upper and lower outer reinforcing steel members 12 and 12 are connected to the inner cylindrical shell and the outer cylindrical shell. It is composed of a plurality of connecting materials 14, ..., And a plurality of brace materials 15, ... That diagonally connect the auxiliary steel materials 11 and 12. Therefore, the gantry frame 10 is configured in a cylindrical piece shape (thick cylindrical shell shape) having high rigidity as a whole.

Then, the main bar 41 on the inner side of the cross section is attached to the inner auxiliary steel material 11. That is, the main bars 41, ... Are installed at equal intervals on the inner reinforcing steel material 11 by using the template (21, 22). Further, as shown in FIGS. 4, 5, and 8, the shelf members 13a project horizontally at equal intervals in the vertical direction on the five vertical members 13 extending in the vertical direction. .. Then, the reinforcing bars 42, ... Are installed so as to be bridged over the shelf members 13a, 13a at the same height.

Similarly, the main bar 41 on the outer side of the cross section is attached to the outer auxiliary steel material 12. That is, the main bars 41, ... Are installed at equal intervals on the outer reinforcing steel material 12 by using the template (21, 22). Further, as shown in FIGS. 4, 5, and 8, the shelf members 13a project horizontally at equal intervals in the vertical direction on the five vertical members 13 extending in the vertical direction. .. Then, the reinforcing bars 42, ... Are installed so as to be bridged over the shelf members 13a, 13a at the same height.

Here, the configuration of the template (21, 22) will be described with reference to FIGS. 6 and 7. The template (21, 22) is composed of an upper template 21 for positioning the upper end of the main bar 41 and a lower template 22 for positioning the lower end of the main bar 41. As shown in FIG. 6, the lower template 22 has a shape in which a plurality of holes 22a are provided at equal intervals (inscribed angles) on an arc-shaped flat steel plate. Then, it is installed and fixed on the ground below the gantry frame 10, and the lower ends of the plurality of main bars 41, ... Are fitted therein.

As shown in FIG. 7, the upper template 21 has a shape in which a plurality of short cylindrical containers 21a are provided at equal intervals (equal circumferential angles) on an arc-shaped flat steel plate. Then, the upper ends of the plurality of main bars 41, ... Are fitted above the gantry frame 10. Therefore, when the reinforcing bar unit U is suspended, the lower template 22 is left in the work yard, but the upper template 21 is fitted on the main bar 41, ... Of the reinforcing bar unit U. After that, the upper template 21 is removed before the upper reinforcing bar unit U is suspended and installed.

As shown in FIG. 8, the upper and lower reinforcing bar units U and U are connected to the reinforcing bar pin 32 attached to the upper end of the vertical member 13 of the existing lower reinforcing bar unit U and the upper reinforcing bar unit U. It is composed of a cylindrical stapler 31 attached to the lower end of the vertical member 13. That is, in the reinforcing bar unit U, the cylindrical stapler 31 is fixed to the lower end of the vertical member 13, and the reinforcing bar pin 32 is fixed to the upper end of the vertical member 13.

Then, when the reinforcing bar units U and U are overlapped, the reinforcing bar pin 32 of the lower reinforcing bar unit U is inserted into the cylindrical stapler 31 of the upper reinforcing bar unit U, so that the upper reinforcing bar unit U is highly accurate. It can be positioned with. After that, by tightening the bolts 33 and 33 to the nuts (not shown) charged in the cylindrical stapler, the relative positional relationship between the two can be fixed. The above-mentioned upper end and lower end members may be arranged in reverse.

On the other hand, as shown in FIG. 9, bolt holes are provided in advance at the ends of the reinforcing steel materials 11 (12) at the connecting points of the left and right reinforcing bar units U and U, and the adjacent reinforcing steel materials 11 (12) are butted against each other. In the state, they are connected by the splicing plates 51 and 52. That is, the vertical flange of the auxiliary steel material 11 (12) is connected to the first splicing plate 51 spanned between the adjacent auxiliary steel materials by bolts / nuts 53, ..., And the auxiliary steel material 11 (12) is connected. ) Is connected to a second splicing plate 52 spanned between adjacent auxiliary steel materials by bolts / nuts 53, ....

(Reinforcing bar assembly method)
Next, among the whole steps described in the first embodiment, each step (that is, step S1, step S3, and step S4) related to the method of assembling the reinforcing bar will be described.

(Step S1: Step of constructing the gantry frame and step of attaching the reinforcing bar)
First, the "step of constructing the gantry frame 10 and the step of forming the reinforcing bar unit U" corresponding to step 1 will be described. The reinforcing bar unit U is constructed by being divided into four parts, 10 m in the vertical direction (cylindrical axis direction) and 90 degrees in the circumferential direction.

(1-1) First, for each reinforcing bar unit U, a cylindrical shell-shaped pedestal frame 10 using equilateral angle steel (angle) to which reinforcing bars are attached is constructed.

(1-2) Next, a plurality of main bars (vertical reinforcing bars) 41, ... Are attached to the gantry frame 10. When attaching the main bar 41, dedicated templates 21 and 22 are used at the lower end and the upper end, respectively. The lower template 22 is fixed to the leveling concrete for work, and the main bar 41 is fitted into the lower template 22 for positioning. By inserting (fitting) the detachable upper template 21 into the upper end, the circumferential spacing of the main bars 41, ... At the time of assembly is made constant.

(1-3) Next, a plurality of reinforcing bars (circumferential reinforcing bars) 42, ... Are attached to the outside of the main reinforcing bars 41, ... To the gantry frame 10. The reinforcing bar 42 is placed on a shelf member (reinforcing bar pedestal) 13a that horizontally projects from the vertical member 13 of the gantry frame 10.

(1-4) After the installation of the reinforcing bars 42, ... Is completed, the shear reinforcing bars (not shown), ... Are installed to complete the assembly of the reinforcing bar unit U.

(Step S3: Suspension of the reinforcing bar unit)
Next, the "reinforcing bar unit U hanging step" corresponding to step 3 will be described.

(3-1) The completed reinforcing bar units U are suspended one by one by a lifting machine such as a crane and placed inside a circular shaft. When the reinforcing bar unit U is suspended, the upper end of the gantry frame 10 of the existing (lower) reinforcing bar unit U is previously installed in the cylinder of the cylindrical stapler 31 previously attached to the lower end of the (upper) reinforcing bar unit U to be suspended. It is installed so as to pass the attached reinforcing bar pin 32.

(Step S4: Connection of reinforcing bar units)
Next, the “reinforcing bar unit U connecting step” corresponding to step 4 will be described.

(4-1) Next, after the rebar unit U is completely suspended, the upper and lower rebar units U and U are connected and fixed by tightening the screws of the cylindrical stapler 31.

(4-2) Next, the gantry frames 10 and 10 at the connection points between the reinforcing bar units U and U in the circumferential direction are connected to each other by using the splicing plates 51 and 52.

(4-3) Subsequently, using a mechanical joint that has been assembled in advance, the reinforcing bars are connected to each other at the joints between the main reinforcing bars 41 and 41 and between the reinforcing bars 42 and 42. Further, by the time the next (upper) reinforcing bar unit U is suspended, the upper template 21 is removed and a mechanical joint is installed at the upper end of the main reinforcing bar (axial reinforcing bar) 41.

(4-4) When the installation of the reinforcing bar unit U is completed, the installation process of the formwork unit is started.

(effect)
Next, the effects of the reinforcing bar unit U will be described while enumerating them.
(1) As described above, the reinforcing bar unit U of the present embodiment is a reinforcing bar unit U arranged in a cylindrical or cylindrical reinforced concrete structure, and includes a gantry frame 10 configured in a cylindrical shell shape. It is provided with a main bar 41, which is a plurality of vertical reinforcing bars attached to the gantry frame 10, and a band reinforcing bar 42, which is a plurality of circumferential reinforcing bars. Therefore, by constructing the reinforcing bar unit U having high rigidity and high mounting accuracy of the reinforcing bar, it is possible to reduce the number of spacers that are troublesome to install.

The inner formwork construction method of the present invention is particularly effective for a substantially circular inner formwork on which hydraulic pressure acts at the time of placing concrete, such as when high-fluidity concrete is used. Further, when the formwork has a high rigidity, when used in combination with the high-rigidity reinforcing bar unit U, the effect of suppressing the movement / deformation of both the formwork and the reinforcing bar unit U at the time of placing is large. Compared with the above, it is possible to greatly reduce the number of reinforcing bar spacers.

(2) Further, the main bars 41, ... Which are a plurality of vertical reinforcing bars, are positioned by being fitted into the lower template 22 whose lower end is fixed below the gantry frame 10, and the upper end thereof is the gantry frame 10. Since it is fitted into the upper template 21 and positioned above the frame 10, the main reinforcing bars 41, which are vertical reinforcing bars, can be installed with high accuracy on the gantry frame 10. In addition, since the frame 10 has high rigidity, the position accuracy of the main bars 41, ... Can be maintained even when the reinforcing bar unit U is suspended and installed.

(3) Further, the band reinforcing bars 42, ... Which are a plurality of circumferential reinforcing bars, are placed on the plurality of shelf members 13a, ... Attached to the vertical member 13 of the gantry frame 10 in the substantially horizontal direction. Since it is positioned so that the reinforcing bar 42, which is a circumferential reinforcing bar, can be installed with high accuracy on the gantry frame 10. In addition, since the frame 10 has high rigidity, the position accuracy of the reinforcing bars 42, ... Can be maintained even when the reinforcing bar unit U is suspended and installed.

(4) Further, the method of assembling the reinforcing bars of the present embodiment is a method of assembling the reinforcing bars arranged in a cylindrical or cylindrical reinforcing bar concrete structure, and is a step of constructing a frame 10 having a cylindrical shell shape. A process of attaching a plurality of vertical reinforcing bars 41, ..., And a plurality of circumferential reinforcing bars 42, ... To the gantry frame 10 to form a reinforcing bar unit U, and a reinforcing bar unit U. The step of suspending and arranging the reinforcing bars 42, the step of connecting the gantry frames 10 of the reinforcing bar units U adjacent to each other in the circumferential direction, and the reinforcing bar 42 which is the reinforcing bar in the circumferential direction of the reinforcing bar unit U adjacent to the circumferential direction.・ ・ It is equipped with a process of connecting to each other. Therefore, by constructing the reinforcing bar unit U having high rigidity and high mounting accuracy of the reinforcing bar, it is possible to reduce the number of spacers that are troublesome to install.

(5) Further, in the step of attaching a plurality of vertical reinforcing bars 41, ... To the gantry frame 10, the lower ends of the plurality of vertical reinforcing bars 41, ... Are fixed below the gantry frame 10. It includes a step of fitting into the lower template 22 to be fitted, and a step of fitting the upper end into the upper template 21 above the gantry frame 10. Therefore, the main reinforcing bars 41, ..., Which are vertical reinforcing bars, can be installed with high accuracy on the gantry frame 10. In addition, since the frame 10 has high rigidity, the position accuracy of the main bars 41, ... Can be maintained even when the reinforcing bar unit U is suspended and installed.

(6) Further, in the step of attaching a plurality of circumferential reinforcing bars 42, ... To the gantry frame 10, the plurality of circumferential reinforcing bars 42, ... Are attached to the gantry frame 10. It includes a step of placing on a plurality of shelf members 13a, ... Attached in a substantially horizontal direction. Therefore, the band reinforcing bars 42, ..., Which are the reinforcing bars in the circumferential direction, can be installed with high accuracy on the gantry frame 10. In addition, since the frame 10 has high rigidity, the position accuracy of the reinforcing bars 42, ... Can be maintained even when the reinforcing bar unit U is suspended and installed.

(7) Further, a step of connecting the frame 10, 10 of the reinforcing bar units U and U adjacent in the vertical direction to each other, and a main bar 41 which is a vertical reinforcing bar of the reinforcing bar units U and U adjacent in the vertical direction, ... Further include a step of connecting the two to each other. Therefore, the relative positions of the gantry frames 10 and 10 can be positioned with high accuracy. As a result, the main bars 41, which are installed on the upper and lower gantry frames 10 and 10 with high accuracy, can be connected to each other by using a mechanical joint or the like.

(Structure of formwork unit FU)
Here, the configuration of the formwork unit FU, which is an element constituting the formwork, will be described with reference to FIGS. 10 to 17. That is, as shown in FIG. 10, the formwork is composed of a plurality of formwork units FU stacked vertically. For example, assuming that the driving lift is 10.2 m, the driving lift is divided into 6 blocks in the vertical direction by 1.7 m in height to form one block in the height direction. That is, as shown in FIG. 10, six stages of the form unit FU are set as one block (height 10.2 m).

In each formwork unit FU, the reinforcing rings 72 to 74 are inserted between the liner plates 71 as a weir to increase the rigidity of the formwork unit FU in the circumferential direction. That is, as shown in FIGS. 11 and 14, the formwork unit FU is attached to the liner plates 71, 71, 71 for three stages configured in the shape of a cylindrical piece and the upper edge of the uppermost liner plate 71. 72 with an arc-shaped upper reinforcing ring, an arc-shaped lower reinforcing ring 74 attached to the lower edge of the lowermost liner plate 71, and intermediate reinforcing rings 73, 73 attached between the liner plates 71, 71, 71. , Consists of.

As shown in FIG. 12, the liner plate 71 as a weir plate has, for example, an arc shape divided into 16 in the circumferential direction. Conversely, a circular dam is formed by connecting 16 liner plates 71 in the circumferential direction. The rigidity of the liner plate 71 is increased by fixing the upper and lower edges of the liner plate 71 to the reinforcing rings (72, 73, 74) with bolts. It is preferable that the liner plates 71, ... As the weir plate, have a staggered arrangement in which the connection positions in the circumferential direction are shifted with respect to the adjacent upper and lower liner plates 71, ....

As shown in FIG. 13, the upper reinforcing ring 72, the intermediate reinforcing ring 73, and the lower reinforcing ring 74 are made of H-shaped steel, and have, for example, an arc shape divided into eight in the circumferential direction. Conversely, a circular reinforcing ring is formed by connecting eight reinforcing rings (72, 73, 74) in the circumferential direction.

As shown in FIGS. 14A and 14B, the upper reinforcing ring 72 is provided with a semicircular plate-shaped convex portion 75 that protrudes upward and is orthogonal to the circumferential direction. That is, the convex portion 75 is fixed to this concave shape by welding by utilizing the concave shape inside the flange of the upper reinforcing ring 72 which is H-shaped steel. Further, a suspension hole 75a is formed in the vicinity of the center of the convex portion 75. The shape of the convex portion 75, which is an upward protruding portion, is a semicircle, an inverted U-shape, a semi-arc shape, or an acute triangle, and an oblique side such as a jump box and an upper base project laterally from the lower base. It may be a trapezoid, a polygon such as a pentagon whose diagonals do not protrude laterally from the base, such as a piece of shogi.

On the other hand, as shown in FIG. 14A, the lower reinforcing ring 74 is formed with a recess 76 that opens downward. That is, the concave shape inside the flange of the lower reinforcing ring 74, which is H-shaped steel, is used as it is as the concave portion 76.

Further, as shown in FIGS. 15A and 15B, the upper reinforcing ring 72 and the lower reinforcing ring 74 are provided with the alignment rod 84 for facilitating the connection work between the formwork units FU. There is. This alignment rod 84 is realized by inserting a guide pin 83 in common with the sheath pipe 81 attached to the upper reinforcing ring 72 and the sheath pipe 82 attached to the lower reinforcing ring 74.

That is, in the vertical connection between the formwork units FU and FU, the flange of the lower reinforcing ring 74 at the lower end of the upper formwork unit FU is placed on the flange side surface of the upper reinforcing ring 72 at the upper end of the lower formwork unit FU. The side surfaces are line-joined, but the flange side surface is unstable because the width is as narrow as about 1 to 2 cm.

Therefore, by having a "precision-setting and slip-preventing steel material" devised to prevent radial deviation, the radial position during suspension becomes accurate, and the rotation position in the circumferential direction should be aligned. Just do it. Further, the sheath pipes 81 and 82 are welded to the upper and lower reinforcing rings 72 and 74 so that the circumferential and radial deviations do not occur between the installation and the connection by the splicing plate 85, and the upper and lower pipes 81 and 82 are welded after the installation. The misalignment can be prevented by inserting the guide pin 83 so as to pass through the sheath pipes 81 and 82.

Then, as shown in FIGS. 16A and 16B, the upper and lower formwork units FU and FU are connected by bolts by the splicing plate 85. In this construction example, in order to secure the rigidity in the vertical direction, flat plates are added in the vertical direction at three locations in the circumferential direction (not shown), and the vertical connection (connection) is reinforced by this flat plate. It is carried out at the position.

Specifically, the upper reinforcing ring 72 of the lower formwork unit FU and the lower reinforcing ring 74 of the upper formwork unit FU were accurately positioned, and the flange end faces of the H-shaped steel were overlapped with each other. In this state, the splicing plate 85 is tightened and fixed by bolts and nuts 86. Since the formwork units FU and FU are installed with high accuracy by the above-mentioned "convex portion (precision and slip prevention steel material)", the adjustment work of the position in the radial direction is almost unnecessary in this embodiment. ..

(How to build the formwork)
Next, among the whole steps described in the first embodiment, the steps related to the method of constructing the formwork (that is, step S5) will be described. As described below, the method of constructing the formwork includes a step of constructing the formwork unit FU, a step of lifting the formwork unit FU, a step of superimposing the formwork units FU and FU, and a formwork unit FU. It includes a step of connecting FUs and the like.

(5-1) In the process of constructing the formwork unit FU, as shown in FIGS. 11 to 14, first, the liner plate 71 and the reinforcing rings 72 to 74 are connected to form an arc divided into four in the circumferential direction. It is carried out by manufacturing a formwork piece in a factory and assembling four formwork pieces into a circular formwork unit FU. In this way, the formwork unit FU, which is a circular formwork having a predetermined height (for example, 1.7 m), is constructed.

(5-2) The step of lifting the formwork unit FU is performed by suspending the upper formwork unit FU, which is formed in a circular shape, by a crane. For the suspension, the suspension hole 75a provided in the convex portion 75 of the upper reinforcing ring 72 of the formwork unit FU is used.

(5-3) In the step of superimposing the formwork units FU and FU, as shown in FIG. 17, the recess 76, which is the flange portion of the lower reinforcing ring 74 of the upper formwork unit FU, is the lower formwork unit. It is carried out by automatically descending to an appropriate position in the radial direction along the arc shape of the convex portion 75 of the upper reinforcing ring 72 of the FU. That is, if the relative position is displaced in the radial direction (horizontal direction in the figure), the concave portion 76 comes into contact with one side of the arc of the convex portion 75, and a drag force is applied in the diagonal direction (including the lateral component). To receive it, if you lower it slowly, the position will be forced.

That is, as shown in FIG. 17A, if the upper formwork unit FU is radially outside the lower formwork unit FU, the flange inside the upper formwork unit FU in the radial direction goes up first. It is in contact with the inner side of the radial center of the upper reinforcing ring of the convex portion 75 of the reinforcing ring 72. The inside of the upper reinforcing ring of the convex portion 75 from the center in the radial direction is inclined so that the outside in the radial direction is high and the inside is low. As a result, of the flanges at the lower end of the lower reinforcing ring 74 of the upper formwork unit FU, only the inner flange in the radial direction comes into contact with the convex portion first. At this time, the inner flange of the lower end flange of the lower reinforcing ring 74 of the upper formwork unit FU receives a force from the convex portion inward in the radial direction due to the weight of the upper formwork unit FU, and the upper mold. The entire frame unit moves inward in the radial direction.

On the other hand, as shown in FIG. 17B, if the upper formwork unit FU is inside the lower formwork unit FU in the radial direction, the flange on the outer side in the radial direction of the upper formwork unit FU goes up first. The convex portion 75 of the reinforcing ring 72 is in contact with the outer side of the radial center of the upper reinforcing ring. The outside of the center of the upper reinforcing ring of the convex portion 75 in the radial direction is inclined so that the inside in the radial direction is high and the outside is low. As a result, of the flanges at the lower end of the lower reinforcing ring 74 of the upper formwork unit FU, only the flange on the outer side in the radial direction comes into contact with the convex portion first. At this time, the outer flange of the lower end flange of the lower reinforcing ring 74 of the upper formwork unit FU receives a force from the convex portion to the outer side in the radial direction due to the weight of the upper formwork unit FU, and the upper mold. The entire frame unit moves outward in the radial direction.

As a result, the radial position of the formwork unit FU suspended from above due to the presence of the convex portion 75 may be radially inside or radially outside of the lower formwork unit FU. By the act of hanging, as shown in FIG. 17 (c), it is automatically installed at a predetermined position in the radial direction.

As shown in FIG. 15, the upper and lower formwork units FU and FU are connected by using the positioning rod 83 in order to prevent the upper and lower formwork units FU and FU from being displaced due to unexpected earthquake motion or the like until the connection (connection) of the upper and lower formwork units FU and FU. Temporarily fix.

(5-4) As shown in FIG. 16, the step of connecting the mold units FU and FU is performed by attaching a splicing plate 85 to the inside of the reinforcing rings 72 and 74 in both the vertical direction and the circumferential direction to reinforce the mold units. This is carried out by sewing the reinforcing rings 72 and 74 and the splicing plate 85 using bolts and nuts 86 while putting a hand in the gap between the rings 72 and 74 and the liner plate 71 which is a weir and pressing the nut.

(effect)
Next, the effects of the formwork unit FU of this embodiment will be described while enumerating them.

(1) As described above, the formwork unit FU of this embodiment is a formwork unit FU of a cylindrical or cylindrical reinforced concrete structure. The formwork unit FU is a liner plate 71 which is a weir plate formed in a cylindrical piece shape, and an arc-shaped upper reinforcing ring 72 attached to the upper edge of the liner plate 71, and is a convex portion protruding upward. It comprises an upper reinforcing ring 72 having a 75 and a lower reinforcing ring 74 having an arcuate lower reinforcing ring 74 attached to the lower edge of the liner plate 71 and having a recess 76 that fits into the convex portion 75. ing. Therefore, by using the formwork unit FU, a circular formwork that can be quickly installed and has high rigidity can be obtained.

Therefore, if the formwork unit FU is used, it is possible to realize the rapid speed of the skeleton construction site and to secure the roundness accuracy. In addition, since the formwork unit FU has high rigidity, it can be used for the large lateral pressure (concrete hydraulic pressure) generated when high-fluidity concrete is placed, which is necessary to enable concrete placement with a lift height of 10 m. It has a structure that can withstand. In other words, since the circular formwork can be constructed in advance with the groundwork, the amount of work at the skeleton construction site can be reduced, and the entire process can be reduced to about 1/2 or less.

Furthermore, since it is possible to increase the rigidity of the formwork unit FU, when used in combination with the highly rigid reinforcing bar unit U, the effect of suppressing the movement and deformation of both the formwork and the reinforcing bar body during casting can be suppressed. It becomes possible to increase the number, and it becomes possible to reduce the number of reinforcing bar spacers as compared with the conventional technique.

In addition, in order to divide the formwork unit FU into cylindrical piece-shaped formwork pieces, one side of the three sides of the formwork piece is 2.5 m or less, and one side is approximately 3.5 m or less. It will be possible to manufacture pieces at the factory and transport them using public roads. In addition, by standardizing the formwork piece itself, the man-hours in the factory can be reduced compared to simple manufacturing.

(2) Further, the convex portion 75 of the upper reinforcing ring 72 is formed in a semicircular shape, an inverted U shape, or a semicircular arc shape, so that when the upper and lower formwork units FU and FU are overlapped with each other, the upper and lower formwork units FU and FU are overlapped. The convex portion 75 is easy to position and easy to manufacture.

(3) Further, by providing the hanging hole 75a for hanging in the convex portion 75 of the upper reinforcing ring 72, the precision-improving and slip-preventing steel material can be used as a hanging ring. Further, since the hanging holes 75a are dispersedly arranged in each formwork piece, the hanging holes 75a can be lifted in a well-balanced manner when the hanging holes 75a are used.

(4) Then, the method for constructing the formwork of this embodiment is a method for constructing a formwork using any of the above-mentioned formwork units FU, and is a step of constructing the formwork units FU and FU and suspension. The formwork unit FU is lifted by using the hole 75a, and the concave portion 76 of the lower reinforcing ring 74 is fitted to the convex portion 75 of the upper reinforcing ring 72, and the formwork unit FU and FU are overlapped with each other. It is provided with a step of connecting the formwork units FU and FU in the vertical direction. Therefore, by using the formwork construction method, it is possible to construct a circular formwork that can be installed quickly and has high rigidity.

(5) Further, the sheath pipes 81 and 82 are attached to the upper reinforcing ring 72 and the lower reinforcing ring 74 of the formwork unit FU, and the step of superimposing the formwork units FU and FU is the sheath pipe of the lower reinforcing ring 74. A step of communicating the guide pin 83 with the sheath pipe 81 of the upper reinforcing ring 72 and the 82 is included.

Although Examples 1 to 3 of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to these Examples 1 to 3, and the design does not deviate from the gist of the present invention. Modifications are included in the present invention.

For example, the concrete used is not limited to high-fluidity concrete.

Further, the weir plate is not limited to the liner plate, and a steel plate other than the liner plate may be used as long as the lateral pressure acting on the formwork from the concrete can be supported without leaking the concrete.

Further, the direction of the convex portion 75 is not limited to the radial direction, and may be convex in the circumferential direction or may be convex in both the radial direction and the circumferential direction such as a spherical surface or a cone.

Among the sheath pipes, the sheath pipe 82 attached to the upper reinforcing ring 74 does not have to have a hole penetrating to the bottom. That is, the guide pin 83 penetrates the sheath pipe 81 provided in the lower reinforcing ring 74 of the upper formwork unit FU, and enters the hole of the sheath pipe 82 provided in the upper reinforcing ring 72 of the lower formwork unit FU. As long as it is communicated, the hole of the sheath tube 82 does not have to penetrate to the bottom.

Further, the material used for the gantry frame 10 is not limited to equilateral angle steel (angle) as long as the rigidity required for the gantry frame can be realized, and channel steel, H-shaped steel, flat bars, square pipes and the like can be used. May be good. Furthermore, the material is not limited to steel, but it has a sufficient Young's modulus to realize the rigidity required for the frame, and the linear expansion coefficient is almost the same as that of concrete so as not to induce cracks in concrete due to temperature changes. For example, it may be another metal or material such as stainless steel.

11: Supplementary steel material 12: Supplementary steel material 13: Vertical member 13a: Shelf member 14: Connecting material 15: Brace material 21: Upper template 21a: Short cylindrical container 22: Lower template 22a: Hole 31: Cylindrical stapler 32: Reinforcing bar pin 33 : Bolt 41: Main bar 42: Reinforcing bar 51: Stapler plate 52: Stapler plate 53: Bolt / nut 71: Liner plate 72: Upper reinforcing ring 73: Intermediate reinforcing ring 74: Lower reinforcing ring 75: Convex part (precision) Anti-slip steel material)
75a: Suspension hole 76: Recess 81: Sheath pipe 82: Sheath pipe 83: Guide pin 84: Alignment rod 85: Splicing plate 86: Bolt / nut C: Caisson foundation FU: Formwork unit S: Reinforcing bar U: Reinforcing bar unit

Claims (4)

Cylindrical, elliptical columns, or substantially circular columns including columns with an oval cross section, or cylindrical, elliptical cylinders, or substantially cylindrical reinforced concrete having the contour of an oval cylinder with a flat cross section. It is a frame unit of a structure,
A weir plate constructed in the shape of a substantially cylindrical piece,
An arc-shaped upper reinforcing ring attached to the upper edge of the dam, which has a convex portion protruding upward, and an upper reinforcing ring.
An arcuate lower reinforcing ring attached to the lower edge of the dam, comprising a lower reinforcing ring having a recess that fits into the convex portion .
A formwork unit in which a hanging hole for hanging is provided in the convex portion of the upper reinforcing ring . Cylindrical, elliptical columns, or substantially circular columns including columns with an oval cross section, or cylindrical, elliptical cylinders, or substantially cylindrical reinforced concrete having the contour of an oval cylinder with a flat cross section. It is a frame unit of a structure,
A weir plate constructed in the shape of a substantially cylindrical piece,
An arc-shaped upper reinforcing ring attached to the upper edge of the dam, which has a convex portion protruding upward, and an upper reinforcing ring.
An arcuate lower reinforcing ring attached to the lower edge of the dam, comprising a lower reinforcing ring having a recess that fits into the convex portion .
The convex portion of the upper reinforcing ring is formed into a semicircle, an inverted U shape, a semicircular arc shape, or a polygon including a triangle, a trapezoid, and a pentagon in which the hypotenuse and the upper base do not project laterally from the lower base. And
A formwork unit in which a hanging hole for hanging is provided in the convex portion of the upper reinforcing ring . The method for constructing a formwork using the formwork unit according to claim 1 or 2 .
The process of constructing the formwork unit and
The process of lifting the formwork unit using the suspension hole and
A step of fitting the concave portion of the lower reinforcing ring to the convex portion of the upper reinforcing ring and superimposing the formwork unit.
The process of connecting the stacked formwork units in the vertical direction and
How to build a formwork. A sheath pipe is attached to the upper reinforcing ring and the lower reinforcing ring of the formwork unit.
The step of overlapping the formwork units according to claim 3 , wherein the step of superimposing the formwork units includes a step of communicating a guide pin with the sheath pipe of the lower reinforcing ring and the sheath pipe of the upper reinforcing ring. How to build.

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