JPH07317315A - Self-rising type formwork construction method - Google Patents

Abstract

PURPOSE:To prevent a connection cutting sheet from rising together so as to prevent wear of the surface of concrete without accompanying a troublesome operation. CONSTITUTION:In a self-rising type formwork construction method constructing a concrete structure by arranging a formwork 15 along the sectional form of the concrete structure, providing an connection cutting sheet 26 generating a relative slide against the formwork 15 inside the formwork, placing concrete C inside the connection cutting sheet 26, raising the formwork 15 after hardening the concrete, and repeating these processes, the formwork 15 is made movable in the direction of separating from the connection cutting sheet. Before raising the formwork 15, the formwork 15 is moved in the direction of separating from the sheet 26, and the surface pressure between the formwork 15 and the sheet 26 is reduced. After raising the formwork 15 in this condition, the formwork 15 is moved up to t.he placing position of concrete C interposed with the sheet 26 so as to prepare for placing concrete.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-propelled formwork method suitable for constructing concrete structures such as high piers.

[0002]

2. Description of the Related Art A sliding formwork method has been developed as a method of continuously constructing a concrete structure of this type. The sliding formwork method is a concrete structure in which concrete is placed in the formwork while raising the formwork arranged according to the cross-sectional shape of the structure in small increments by taking a reaction force to the structure with a lifting jack. It is to build objects continuously in the upper direction, placing concrete, assembling and dismantling formwork,
Compared with the method of repeating the work cycle of reassembly, the concrete structure can be constructed in a short time.

In this construction method, however, the formwork rises while it is in contact with the surface of the concrete before the strength of the concrete is sufficiently expressed, so that the surface of the concrete may be uneven in color due to scratches or rust. Not only
Since the mold is raised while cutting the adhesion to the concrete while the mold is in contact with the entire outer surface of the concrete, the sliding resistance is large, and the capacity of the jack must be set large. Had to do.

Therefore, the applicant of the present invention intervenes an edging sheet that causes relative sliding with the formwork inside the formwork, so that when the formwork is raised, the inner surface of the formwork is the surface of concrete. We have already proposed a method to prevent direct rubbing.

[0005]

However, in the construction method in which the edging sheet is placed inside the mold, the frictional force generated between the mold and the sheet is the frictional force generated between the sheet and concrete. If it is larger, a so-called co-climbing phenomenon occurs, in which the sheet is dragged by the lifting of the formwork, and as a result, there is a fear that rubbing marks may remain on the concrete surface.

On the other hand, in order to prevent the edge-cutting sheet from rising up, it is conceivable to preliminarily set an anchor at an appropriate position of the concrete structure and connect the edge-cutting sheet to the anchor. Not only is the work of striking the anchors interlockingly cumbersome, but also the work of removing the connection with the anchors when removing the edging sheet from the surface of the concrete structure is troublesome.

The present invention has been made to solve the above problems, and an object thereof is to prevent the edge-cutting sheet from rising up and to improve the surface finish of concrete without any troublesome work. It is an object of the present invention to provide a self-elevating formwork construction method capable of performing the above.

[0008]

In order to achieve the above-mentioned object, the invention according to claim 1 arranges a mold along the cross-sectional shape of a concrete structure, and forms a mold inside the mold. A self-climbing process for constructing a concrete structure by providing a rimming sheet that causes relative slippage between the rimming sheets, placing concrete inside the rimming sheet, and raising the formwork after the concrete is hardened. In the formwork method, it is possible to move the mold in the separating and contacting direction of the edging sheet, and move the form in a direction of separating from the edging sheet before the mold is raised to move the surface of the form and the edging sheet. After reducing the pressure and raising the formwork in this state,
It is characterized in that the mold is moved to a concrete pouring position where an edge cutting sheet is interposed to prepare for concrete pouring.

According to a second aspect of the present invention, the formwork is composed of a plurality of formwork panels connected through joint flanges, and the joint flanges are fastened by horizontal bolts and nuts. , By loosening the bolts and nuts to expand the form in a horizontal cross-sectional direction to reduce the surface pressure with the edging sheet, while tightening moves the form to the concrete pouring position. To do.

Further, in the invention according to claim 3, the form is composed of a plurality of form panels which are supported by a support work through an expansion and contraction drive mechanism, and the respective forms are expanded and contracted by the expansion and contraction operation of the drive mechanism. The panel is expanded in the horizontal cross-sectional direction to reduce the surface pressure with the edging sheet, while the panel is moved to the concrete pouring position by reducing the surface pressure.

[0011]

According to the above self-elevating formwork construction method, when the formwork is moved in the direction of separating from the edging sheet before the formwork is raised,
When the surface pressure between the mold and the edging sheet is reduced, or when the form moves so that a gap is formed between the frame and the edging sheet, the surface pressure of both is reduced. Therefore, when the mold is raised, it is possible to prevent the edging sheet from being raised together with the rise of the mold.

Moreover, since the surface pressure between the formwork and concrete is reduced, the sliding resistance when the formwork is raised is reduced, and the capacity of the raising means such as the raising jack can be reduced, so that the entire apparatus is improved. The size can be reduced.

In the case of the structure of claim 2, the surface pressure can be reduced only by loosening the bolts and nuts when the mold is raised.

Further, in the case of the constitution of claim 3,
The surface pressure can be adjusted by expanding and contracting the drive mechanism, which is suitable for automation.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 4 show a first embodiment of the present invention and exemplify a case where the construction method of the present invention is applied to the construction of a high pier.

In the Takahashi pier 1 shown in FIGS. 1 and 2, for example, four hollow steel pipes 3 are erected on a foundation 2 constructed above the ground,
A large number of main reinforcements 5 are arranged around the hollow steel pipe 3 and concrete strands C are placed on the inner side surrounded by the self-elevating formwork device 7 while the PC strands 6 forming horizontal reinforcements are further wound around the main reinforcements 5. By doing so, it is constructed in the upward direction.

The H-shaped steel materials 8 are installed on the top of the hollow steel pipe 3 in a state of being combined in a cross beam shape.
It is hung by a large number of PC steel wires 9 which are reaction forces received from the H-shaped steel material 8.

The formwork device 7 includes a formwork 15 arranged along the cross-sectional shape of the high pier 1, a large number of support bars 16 connected to the rear side of the formwork 15, and the outside of the formwork 15. A support 18 that surrounds the support bar 16 and fixes the other end of each support bar 16, and work platforms 19, 20 arranged around the support 18 in three stages.
21 is provided. An ascending jack 24 for inserting the PC steel wire 9 is installed on the upper work platform 19, and by driving the jack 24, a reaction force is applied to the PC steel wire 9 to form the frame device 7
Rises like a scale.

The form 15 is, as shown in FIGS. 2 and 3,
Four formwork panels 15a to 15d surrounding the cross section of Takahashi Pier 1
The frame 26 is divided into four parts, and like the formwork 15, four edge-dividing sheets 26 are arranged vertically in three stages. Each sheet 26 is made of a slightly thick sheet material having smoothness such as polyethylene and polypropylene, and causes relative sliding with the formwork 15. A plurality of sheet pieces 26a constituting each sheet 26
The joints between the horizontal joining ends of ~ 26d and the upper and lower sheets 26 are connected by an adhesive tape or the like, and are assembled into the inner shape of the form 15.

In this embodiment, the joint edges of the form panels 15a to 15d forming the form 15 are provided at the corners, and the corners form an angle of 45 ° from the surface of the form panel. Is integrally formed with the joint flange 28,
Bolts 3 are provided in a plurality of connecting holes formed in the flange 28.
0a is inserted, and the nut 30b on the other side is screwed in, so that the mold 15 is fastened while being reduced in the cross-sectional direction.

The support bar 16 is used for each form panel 1
5a to 15d are supported, but they are loosely coupled with respect to the horizontal cross-section direction, or are connected to the form panel panels 15a to 15d through an appropriate expansion and contraction mechanism to fasten and loosen the bolts and nuts 30a and 3b. Each formwork panel 1 by operation
5a to 15d can be moved back and forth in the horizontal sectional direction.

Further, in the drawing, the form 15 and each sheet 26 are divided into four for simplification, but the number of these divisions is appropriately determined according to the sectional size of the concrete structure to be constructed and the curvature of the corner portion. Set to the number of sheets. Although the seat 26 has three stages, the number of stages can be arbitrarily set according to the rising stroke of the formwork device 7. In this embodiment, the joint flange 28 of the formwork panel 15 is provided at the corner portion so as to project at an angle of 45 ° from the surface of the formwork panel, but the joint flange 28 is not provided at the corner portion. The straight portion may be provided at an angle of 90 °. In this case, it is not possible to reduce the surface pressure with the sheet 26 with respect to the entire cross section of the form 15, but it is possible to contribute to the reduction of the surface pressure as a whole by reducing a part of the surface pressure.

Next, a construction procedure in the above configuration will be described. First, as shown in FIG. 4 (a), with the sheet 26 provided inside the assembled formwork 15, concrete C is poured inside the sheet 26 and spliced on top of the existing concrete C1. .

The seat 26 is installed in the middle work platform 2
It is performed at 0. Each sheet 26 comes into close contact with the inside of the form 15 by the placing pressure of the concrete C, and the concrete C is cured in this state. During this curing period, a work of adding a new sheet 26 on the uppermost sheet, a slime removal, a work of arranging the main bar and the PC strand, and the like are performed.

If the concrete C exhibits a certain level of strength, loosening the bolts and nuts 30a and 30b fastening between the form panel panels 15a to 15d will result in the structure shown in FIG. 4 (b).
As shown in FIG. 5, the formwork panels 15a to 15d are separated from each other and move in a direction away from the surface of the sheet 26, so that the formwork 15 as a whole spreads in a horizontal section.

On the other hand, the sheet 26 is left as it is attached to the concrete C. In the figure, the form 15 and the sheet 2
The mold 15 is moved until a gap is formed between the mold 6 and 6, and the surface pressure between the mold 15 and the sheet 26 is 0. However, in reality, the two are completely separated from each other in this way. Alternatively, the surface pressure may be reduced when the two are in contact with each other.
Next, as shown in FIG. 4C, the lifting jack 24 is driven to drive the formwork device 7 together with the formwork 15 and the support work 18.
The entire top of the concrete C that has already been cast is the formwork 1
Raise to the extent that it is supported at the lower end of 5.

At the time of this ascent, a gap is formed between the mold 15 and the sheet 26 (actually, the sheet 2 for the concrete C is reduced by the reduction of the surface pressure between them).
6 is high), the sheet 26 can be kept on the outer surface of the concrete C without being dragged by the form 15, and the sheet 26 can be reliably prevented from rising together.

After the raising operation of the formwork device 7 is completed, if the flanges 28 are fastened again via the bolts and nuts 30a and 3b, the formwork 15 is contracted and newly installed as shown in FIG. 4 (d). Closely adheres to the outer surface of the sheet 26 that has been added to
Prepare for the next concrete placement.

In parallel with this placing work, the sheet 26 exposed from the lower part of the formwork 15 is dismantled on the lower work platform 21 and peeled off from the surface of the concrete C, whereby the exposed surface of the concrete C is removed. The sheet 26 is smooth according to the smoothness of the sheet 26, and good surface properties can be obtained. Further, the disassembled sheet pieces 26a to 26d are conveyed to the work platform 20 in the middle stage and sequentially diverted.

Therefore, the high pier 1 having the required height can be completed by sequentially repeating the above work cycle.

FIGS. 5A and 5B show a second embodiment of the present invention. In the figure, the form frame panels 15a to 15d that form the form frame 15 are supported inside the supporting structure 18 via an expansion and contraction drive mechanism, that is, a plurality of support jacks 40, instead of the support bars 16, and each of the support jacks 40 is supported. The seat 26 can be brought into and out of contact with the forward / backward movement. Therefore, in this embodiment, if the form jack panels 15a to 15d are in contact with the seat 26 as shown in (a), as shown in (b), if the support jacks 40 are simultaneously moved backward, the seat 26 is released. Since they are separated from each other, the work of fastening and loosening the bolts and nuts 30a and 30b as in the first embodiment is unnecessary, and the work can be automated.

In each of the above embodiments, the sheet 26 is installed at a predetermined position and then the mold 15 is raised. However, it is also possible to raise the mold 15 and then install the sheet 26 inside thereof.

Furthermore, it goes without saying that the present invention can be applied to concrete structures other than Takahashi piers.

[0034]

As described above in detail with reference to the embodiments, in the self-elevating formwork method according to the present invention, it is not necessary to hit an anchor to the concrete structure, so that the work is easy, Since the surface pressure between the formwork and concrete is reduced when the formwork is raised, it is possible to prevent the edge cutting sheet from being raised together with the rise of the formwork,
You can get a beautiful concrete surface.

Further, since the frictional force when the mold is raised is reduced, it is possible to reduce the driving power of the jack or the like that raises the mold, and thus it is possible to downsize the entire apparatus. .

Furthermore, since the formwork is configured to move in the contacting / separating direction of the edging sheet, as described in the embodiment, the concrete structure has a closed cross section or a shape having a corner portion. Even if there is, it is possible to prevent the edge cutting sheet from rising up together, and it can be applied to concrete structures of various shapes.

[Brief description of drawings]

FIG. 1 is an overall explanatory view according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is an exploded perspective view showing a mold and a sheet in the same apparatus.

FIG. 4A to FIG. 4D are half cross-sectional explanatory views of a work procedure in the same construction method.

5 (a) and 5 (b) are half cross-sectional explanatory views showing a second embodiment of the present invention.

[Explanation of symbols]

 1 Takadashi (concrete structure) 5 Vertical main bar 6 PC strand 7 Formwork device 15 Formwork 15a to 15d Formwork panel 16 Support bar (support) 18 Support work 24 Lifting jack 26 Edge cutting sheet 28 Flange 30a, 30b Bolt Nut 40 Support Jack C Concrete

Claims (3)

[Claims] 1. A formwork is arranged along the cross-sectional shape of a concrete structure, and an edging sheet that causes relative sliding with the formwork is provided inside the formwork, and the inside of the edging sheet is provided. In a self-elevating formwork method of constructing a concrete structure by placing concrete on the concrete and repeating the step of raising the formwork after hardening of the concrete, the formwork can be moved in the direction of separation and contact of the edging sheet. Before moving up the mold, the mold is moved in a direction away from the edging sheet to reduce the surface pressure between the mold and the edging sheet, and after raising the mold in this state, the form A self-elevating formwork method, characterized by moving to a concrete pouring position where an edge cutting sheet is interposed to prepare for concrete pouring. 2. The mold is composed of a plurality of mold panels connected via joint flanges, and the joint flanges are fastened together by bolt nuts in a horizontal direction, and the bolt nuts are loosened. The self-elevation system according to claim 1, wherein the form is expanded in a horizontal cross-sectional direction to reduce the surface pressure with the edging sheet, and the form is moved to the concrete pouring position by tightening. Formwork method. 3. The form frame is composed of a plurality of form frame panels supported by a support mechanism through an expansion and contraction drive mechanism, and the expansion and contraction operations of the drive mechanism expand each of the form frame panels in a horizontal sectional direction. While reducing the surface pressure with the edge cutting sheet,
The self-elevating formwork method according to claim 1, wherein the formwork is moved to a concrete pouring position by being reduced.