JPH0583103U - External member for the formwork of concrete structures - Google Patents

Abstract

(57) [Summary] [Purpose] It is possible to build a beam or column with excellent strength by increasing the bonding force between the formwork external member using precast concrete and the concrete placed inside it. [Structure] An outer shape member 1 that matches the outer shape of a beam or a column is formed by using precast concrete, and a stripe-shaped concave portion 5 is provided on the entire inner surface of the outer shape member 1, and concrete cast into the inside forms the concave portion 5. By embedding it, it is possible to increase the bonding force between the two and form a beam or column with excellent strength.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an outer shape member also used as a formwork of a concrete structure, which is used for constructing a beam or a pillar of a concrete structure.

[0002]

[Prior Art]

 Conventionally, in the construction of concrete structures, beams and columns were formed by assembling formwork on site and placing concrete after arranging concrete.

However, since the conventional construction methods as described above require a lot of materials and take a long construction period, in recent years, in the construction of beams and columns of concrete structures, beam and column construction methods have been used. An external member that also serves as the formwork for the pillar is made of precast concrete, and after this external member is brought to the site and placed, the reinforcement is laid inside the external member to pour the concrete into the beam or pillar. A construction method for forming the is proposed.

By the way, in the construction of beams and columns using the above-mentioned construction method, in order to obtain the one having excellent strength, it is necessary to improve the bonding strength between the inner surface of the outer shape member and the concrete cast inside the outer member. There is.

Conventionally, as the external member used in the above-mentioned construction method, precast concrete is used, and the external shape is formed into a groove-shaped or tubular cross-sectional shape that is the external shape of a beam or a column. It has a structure that can be set.

[0006]

[Problems to be solved by the device]

 However, since the inner surface of the conventional external member is a flat surface, the adhesive strength between the concrete cast inside and the precast concrete is low, and it is difficult to improve the strength of the beam or column.

Therefore, the present invention is directed to a concrete structure capable of forming a beam or column having excellent strength by improving the adhesive bond strength between the external member using precast concrete and the concrete placed on the inner surface side thereof. The challenge is to provide an external member that also serves as a formwork for an object.

[0008]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention has a structure in which an outer shape member that also serves as a mold for molding a concrete structure is formed of precast concrete, and a striped concave portion is provided on the entire inner peripheral surface of the outer shape member. Is adopted.

[0009]

[Action]

 An external member that also serves as a formwork for forming beams and columns of a concrete structure is formed by using a precast concrete, and by placing concrete in this external member, the external member will be the external shape as it is. Pillars are formed.

Since the striped concave portion is provided on the entire inner surface of the precast concrete, the adhesive force between the precast concrete and the concrete is improved, and the strength of the beam or column can be improved by increasing the bonding force between the two. it can.

[0011]

【Example】

 An embodiment of the present invention will be described below with reference to the accompanying drawings.

The first example shown in FIGS. 1 and 2 shows a beam formwork / exterior member 1 for forming a beam of a concrete structure, which is made of precast concrete and is formed from the bottom wall 2 and the side walls 3 and 3. The star-shaped straps 4 projecting above the upper surface opening are fixed to the outer shape member 1 at regular intervals in the longitudinal direction.

Stripe-shaped recesses 5 are provided on the entire inner surfaces of the bottom wall 2 and the side walls 3 and 3 of the outer member 1.

The outer member 1 is formed by using precast concrete so that the outer surfaces of the bottom wall 2 and the side walls 3 and 3 become the outer shape of the beam as it is, and the stripe-shaped concave portion 5 provided on the entire inner surface has an outer shape. The inner die used for forming the inner surface of the member 1 can be easily provided by forming a striped steel plate.

Although not shown, the inner die used for forming the inner surface uses striped steel plates on the lower surface and the three surfaces on both sides so that the striped convex portions project outward, and the lower portion can be folded in two. However, a structure that can be removed from the mold without any problem may be adopted.

Next, a second example shown in FIG. 3 shows an outer shape member 1a which also serves as a pillar formwork for forming a pillar of a concrete structure, and which is made of precast concrete and formed into a rectangular tube shape having four surrounding walls. A striped concave portion 5 is provided on the entire inner peripheral surface of the outer shape member 1a.

Also in the case of this pillar form, the outer member 1a is formed so that the outer surface is the outer shape of the pillar as it is, and the striped concave portion 5 on the entire inner peripheral surface uses a striped steel plate for the inner die. Can be formed by

The outer shape member 1a is reinforced by embedding hoop muscles.

The external member of the present invention has the above-described structure, and when the concrete structure is constructed, the external member 1 also serving as the beam form is formed on the beam forming portion, and the column forming portion is formed on the column forming portion. The outer member 1a which also serves as a frame is arranged, and a predetermined reinforcing bar is incorporated into the outer members 1 and 1a, and then concrete is placed to form a beam or a pillar having the outer members 1 and 1a as an outer shape.

Since the outer shape members 1 and 1a are provided with stripe-shaped recesses 5 on the entire inner surface, the outer shape members 1 and 1a made of precast concrete and the concrete cast therein are not recessed. By filling 5 with concrete, the adhesive strength is improved, and by increasing the binding strength between the two, it is possible to form beams and columns with excellent strength.

[0021]

【effect】

 As described above, according to the present invention, since the striped concave portion is provided on the entire inner surface of the external member formed using precast concrete, the bonding force between the external member and the concrete cast inside the external member is It is possible to improve the strength of the beam or column formed by the external member and the concrete cast inside the external member.

Further, the striped concave portion provided on the inner surface of the outer member can be easily formed by using a striped steel plate for the forming frame.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an external member for a beam according to the present invention.

FIG. 2 is an enlarged vertical sectional view of an essential part of the above.

FIG. 3 is a perspective view showing an example of an external member for a pillar.

[Explanation of symbols]

 1, 1a External member 5 Striped recess

Claims (1)

[Scope of utility model registration request] 1. An external member that also serves as a formwork for a concrete structure, in which an external member that also serves as a molding frame for the concrete structure is formed of precast concrete, and a striped recess is provided on the entire inner peripheral surface of the external member.