JPH09177318A - Form device for construction of postlike concrete structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To contrive to simplify the construction of a form of a postlike concrete structure and enhance construction efficiency and economical efficiency. SOLUTION: Brackets 4 and 5 are projectingly provided on the inside (concrete placement side) on both sides of each of lateral batter materials 1 of plane forms ranging from A1 to A4 along the peripheral surface of a post-like concrete structure to be constructed, thereby binding the plane forms A1 to A4 with brackets 4 and 5 respectively with pins or the like at a binding area 8. When concrete 8 is placed and the lateral batter materials are subjected to a side pressure, a deviated load accompanied by the distance L between the longitudinal axis of the lateral batter materials 1 and the binding area 8 interacts upon each other, thereby producing reversed deflections of the lateral batter materials 1, which serve to reduce the deflection of the forms attributable to the placement of concrete.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a formwork apparatus used to reinforce a columnar concrete structure or an existing columnar structure with concrete.

[0002]

2. Description of the Related Art In order to construct a concrete structure having a columnar shape, conventionally, a concrete form is placed by connecting surface formwork along the outer peripheral surface of the structure to be constructed. For example, as shown in FIG. 4, in the surface form A, usually, horizontal flap materials 1, 1 arranged at intervals in the vertical direction are joined by vertical flap materials 2, 2 arranged at intervals in the horizontal direction, It is formed by attaching a dam 3 to the inside of the vertical flaps 2 and 2 (concrete pouring side), and four such surface molds A are projected from the ends of the horizontal flaps 1 and 1 with respect to each other. Connections 8 and 8 are made by pins or the like via the brackets 4 and 4.

[0003]

In the conventional formwork as described above, the formwork tends to bulge outward and flex as shown by the chain line in FIG. 4 due to a large lateral pressure due to the pouring of concrete. In order to prevent such bending, many formwork clamp bolts have been conventionally used or a large cross-section flap material has been used.Both of them have poor construction efficiency or a large amount of consumable materials. Formwork construction could not be carried out economically.

In recent years, as a countermeasure against earthquakes and the like, reinforcement work has been performed by placing concrete of a required thickness around a deteriorated columnar structure or a columnar structure requiring reinforcement. In such a mold construction, it is very troublesome to use the mold tightening bolts.

As a method of solving such a problem, for example, as described in Japanese Patent Publication No. 61-56745, a flexure adjusting device is provided on a mold body, and the flexure (concrete placement) is preliminarily set on the mold frame. It has become possible to pour concrete by giving a flexure in the direction opposite to the flexure in which the mold swells outward under pressure). However, even with this method, since a special bending adjusting device having a truss structure is provided on the form, the form is complicated and expensive, and the operation is troublesome and requires skill.

The present invention has been made in order to solve the above-mentioned conventional problems, and does not use mold clamping bolts or complicated flexure adjusting devices, etc. An object of the present invention is to provide a formwork apparatus for constructing a columnar concrete structure, which is capable of economically performing highly accurate construction by applying a frame.

[0007]

The structure of the present invention for achieving the above object will be described with reference to the drawings corresponding to the embodiments. Along with this, in a formwork apparatus formed by joining a plurality of surface formworks A _{1 to} A ₄ to each other at their ends, the lateral flap material 1 of at least one surface formwork It is characterized in that it is connected 8 to the lateral flap material 1 of the adjacent surface form at a position displaced inward from the axis of the concrete.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention. The formwork apparatus of this embodiment is intended for a columnar concrete structure having a quadrangular plane cross section, and is formed by connecting _four surface formworks A _{1 to} A ₄ along the outer periphery of the structure in a frame shape. ing.

The surface molds A _{1 to} A ₄ are composed of a plurality of horizontal flap materials 1, 1 arranged vertically at a required interval, and vertical flap materials 2, 2 arranged at a required lateral distance. Are connected to each other, and the weir plate 3 is attached to the inside of the vertical flaps 2 and 2 (concrete pouring side). Then, each surface type frame A ₁ to A ₄
The first brackets 4 projecting inward are provided inside one end (concrete pouring side) of each of the horizontal flaps 1, 1 and are slightly smaller than the other ends of the horizontal flaps 1, 1. The second brackets 5 are provided on the inner sides of the inner sides.

The four surface molds A _{1 to} A ₄ have the other end portions of the horizontal buttery members 1, 1 of the other surface molds adjacent to the end faces on one end side of the lateral buttery members 1, 1. The first bracket 4 and the second bracket 5 are combined so as to be close to each other on the inner side surfaces thereof, and are coupled 8 and 8 by a pin or the like.
As a result, the joint portions 8 and 8 of the horizontal mold members A _{1 to} A ₄ with respect to the horizontal flap members 1 and 1 are biased inward by a considerable distance L from the center line of the plane of the horizontal flap members 1 and 1. It is in the position where

The formwork apparatus of the present invention comprises the connecting portions 8 and 8 of the lateral butter members 1 and 1 which resist the lateral pressure caused by pouring concrete.
However, since they are located inside the center lines of the lateral flap materials 1 and 1, lateral pressure (solid arrow) acts on each lateral flap material 1 and 1 to bulge outward, as shown in FIG. When the bending is caused to occur, the lateral flap materials 1, 1 are adjacent to each other.
The eccentric load with the distance L from the center line of the lateral flap material 1 to the connecting portion 8 by the force transmitted from
Acts on the joint portion 8 to cause reverse bending (chain line b) to bulge inward (concrete pouring side),
This offsets the bending due to the lateral pressure, and the bending of the lateral flap material 1 is reduced.

FIG. 3 shows an embodiment suitable for a concrete structure having a rectangular cross section. In this case, the two facing surface molds A _{1 to} A ₃ are formed to have a lateral width longer than the other two facing surface molds A ₂ and A ₄ , so that the surface molds A ₁ and A ₄ are inevitably formed. The horizontal flap materials 1a, 1a of A ₃ are formed longer than the horizontal flap materials 1b, 1b of the surface formwork A ₂ , A ₄ .

In the case of this embodiment, the horizontal flaps 1a, 1a, which are long, have the horizontal flaps 1a on the inner sides of both ends thereof.
Corresponding to the length, the brackets 6, 7 longer than the brackets 6, 6 projecting inside both ends of the short horizontal flaps 1b, 1b are provided so as to project, and the connecting portion 8 of both brackets 6, 7 is provided.
Is the distance L ₁ from the center line of the short horizontal flaps 1b, 1b.
Distance L ₂ from the center line of the longer horizontal flap 1a, 1a
Is going to be large. As a result, an eccentric load according to the increased distance L ₂ acts, and a large amount of reverse bending occurs. Therefore, the long lateral flap material 1a can be made to have the same cross section as the short lateral flap material 1b.

The formwork apparatus of the present invention can be used not only for construction of a new columnar concrete structure, but also for formwork construction for reinforcing an existing columnar structure with concrete. In this case, as shown in FIGS. 1 and 3, four surface molds A _{1 to} A ₄ are assembled with a required space from the peripheral surface of the existing columnar structure (shown by a chain line) B.
At that time, the space between the existing columnar structure B and the surface molds A _{1 to} A ₄ can be maintained by a simple method in which a rod or the like is appropriately arranged between them.

It should be noted that the present invention is not limited to the construction of a columnar concrete structure or a reinforced concrete having a quadrangular cross section as in each of the above-mentioned embodiments, and the plane cross section is polygonal, circular or elliptical. It can be widely applied to various shapes and the like.

When it is not necessary to provide a structure in which the eccentric load is generated in all the transverse flaps of the _four surface formwork A _{1 to} A ₄ , only the required surface formwork has this structure, and the other ones have eccentric load. It can be assumed that it does not occur. For example, a column having a long and narrow rectangular cross section, in which only the lateral flap material on the long side thereof has an eccentric load structure, and the lateral flap material on the short side does not have an eccentric load.

[0017]

As described above, according to the present invention,
When the concrete is placed, the surface formwork also causes the bending in the opposite direction due to the lateral pressure of the placed concrete, so the reverse bending causes the normal bending of the formwork in the forward direction due to the lateral pressure of the concrete. Since they cancel each other out, the bending of the mold is extremely reduced.

Therefore, the lateral flap material in the formwork apparatus does not have to be a member having a large cross section to counter the lateral pressure of the cast concrete as in the conventional case, or the lateral flap material is prevented from bending due to the lateral pressure. Therefore, it is not necessary to provide a bending adjustment device that applies reverse bending, the mold can be economically manufactured using inexpensive members, and the handling such as set / reset of the mold and transportation is simplified, and the mold construction can be performed. It is possible to improve efficiency and economic efficiency.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the device of the present invention.

FIG. 2 is an explanatory diagram of the same operation.

FIG. 3 is a plan view showing another embodiment of the device of the present invention.

FIG. 4 is a plan view showing a conventional device.

[Explanation of symbols]

A, A _{1 to} A ₄ surface form B B Existing columnar structure 1, 1 a, 1 b Horizontal flap material 2 Vertical flap material 3 Weir plate 4,5, 6, 7 Bracket 8 Connection part

Claims (1)

[Claims] Along with the peripheral surface of the columnar concrete structure to be constructed, in a formwork device formed by joining a plurality of surface formwork to each other at their end portions, at least one surface formwork horizontal flap material,
A formwork apparatus for constructing a columnar concrete structure, characterized in that the formwork is connected to a horizontal spread material of an adjacent surface formwork at a position displaced inwardly from the axis of the horizontal spread material, where concrete is placed.