JPS61122371A - Mold frame apparatus for arch concrete - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a formwork apparatus applied to the construction of arch concrete in arch bridges and the like.

"Prior Art" Recently, deterioration and damage of concrete slabs constructed on bridge piers have become a major problem in bridge #It structures such as roads 1 and railways. Deterioration and damage to concrete slabs result from the material properties of concrete that are strong in compression but weak in tension.Dry shrinkage and repeated moving concentrated loads cause cracks, and water that enters through these cracks promotes rusting and expansion of reinforcing bars. It is expected that the concrete will flake off and the reinforced concrete will deteriorate further.

Therefore, in order to cope with such deterioration of concrete, bridge types that match the characteristics of concrete have been studied, and concrete arch bridges, which have been forgotten today, have been attracting attention.

This arch bridge is an excellent structural type for a concrete structure because it becomes a compressed member throughout its cross section when a dead load is applied.This type of bridge prevents concrete deterioration and greatly improves durability. It is certainly possible.

However, when constructing a concrete structure such as an arch bridge, a major problem arises in terms of its construction, especially the formwork facilities required to construct the arch-shaped concrete between the piers. Referring to the explanatory diagram in Figure 2, as a general example of construction, first, each pier 1.1 is constructed to the required height, and many arch-shaped formworks 2 are installed between the existing piers 1.1. It is conceivable to support it by vertical supports 3, 3, . . . . This allows easy and economical construction.

However, in actual construction, the concrete 5 poured between the arched formwork 2 and the outer formwork 4 set opposite to it is piled up sequentially from the bottom of both formworks 2. Therefore, at the initial stage of pouring concrete 5, as shown by the arrow in Figure 2,
The load on the formwork of concrete 5 acts at right angles to the 2m' plane of the weir plate. On the other hand, the support column 3 supporting the formwork part is almost impossible to support in the vertical direction because the angle of intersection with the formwork pattern 2b deviates greatly from the right angle direction. be. Therefore, the arch supporting butterfly 2b needs to have a structure in which horizontal members are provided to withstand horizontal loads. This necessarily results in a truss structure.

Figure 3 shows an example in which the arch support pattern 2b of the formwork has a truss structure.As can be seen from this figure, the arch-shaped formwork 2 becomes a heavy structure. Strong shoring was required to support the structure, making the work difficult and requiring a huge amount of expense.

``Problems to be Solved by the Invention'' The present invention solves the problem of constructing arch concrete formwork as described above by using a common structure of shedding boards and batten materials, without making the formwork a heavy structure. To provide an arch concrete formwork that allows the arch-shaped formwork to be supported almost only by supports, making the formwork simple and lightweight, easy to work with, easy to carry out with power wheels, and significantly reducing costs. This is what I am trying to do.

"Means for Solving the Problems" The present invention provides an arch-shaped formwork to be constructed between existing leg structures, and the upper ends of the pillars are attached at a required distance between both ends of the formwork. The lower ends of each of the pillars are supported near the center of the base between the two leg structures, and the upper ends of each of the pillars are connected to each other by a connecting rod,
Furthermore, it is characterized in that the upper end of the column at the outer end is secured to the base or an existing leg structure.

"Example" Hereinafter, an example of the apparatus of the present invention will be described with reference to FIG.

In FIG. 1, 1. 1 is a leg structure constructed at a predetermined interval before placing the arch concrete 5; 7 is an arch-shaped formwork constructed between the leg structures 1. This form body 7 has a large number of arch-shaped butter materials 7b arranged in parallel, which are connected to each other by horizontal butter materials 16, and a weir plate 7 is placed on the outside of the arch-shaped butter materials 7b
It is formed by attaching a.

On the base 6 in the center between the two leg structures 1.1, the lower ends of the plurality of columns 8m and 8b supporting the formwork body 7 are placed.
The pillars 8a, 8a, which are adjacent to each other and are grounded, and which are located at the outer ends of the pillars, have their tips connected to both ends of the form body 7 via, for example, horizontal butterfly members 16, and other The pillars 8b and 8b are extended radially upward between the pillars 8m and 8JL at the outer ends, and their upper ends are connected to the formwork body 7.
They are connected to each other at required intervals. That is, as shown in the figure, each support 8a * 8b is connected to the base 6
The formwork body 7 is formed in a radial manner with the support point near the upper center part.
The structure supports the following. In addition, each of the above-mentioned pillars 8a.

A telescopic mechanism IO is provided at the lower end of 8b, and by operating this, the length can be freely adjusted.

Each of the pillars 8a, 8'b is integrally connected to each other by connecting rods 9,9... at their upper ends, and furthermore, the pillars 8a, 8m at the outer ends connect their upper ends to the existing ones. It is secured to the leg structure 1.1. In other words, at the upper end of the outer end pillar 8m, there is a telescopic mechanism 1 such as a turnbuckle.
One end of the tension member 2 having a tension member 2 is attached, and the other end is connected to an anchor 13 buried in the leg structure 1 via a bracket 14. Note that the other end of the tensile material 11 can also be tied to the base 6 in the same manner as described above.

"Function" The present invention is constructed as described above, and the formwork body 7 may be assembled externally and brought in, or assembled on site depending on the scale of the arch concrete 5 to be constructed. It is supported by pillars 8, 8, . . . . After the form body 7 is erected, the outer form 4 is erected as shown in FIG. 2, and concrete 5 is poured through the gap 15 (see FIG. 2) formed at the top of the outer form 4.

Therefore, the load direction of the poured concrete 5 acts in a direction perpendicular to the shedding plate surface, so that the formwork body 7'. Yo,)
Tsuyu 9 lines. , Eka, Tsua horizontally facing. Although a large load will be applied to the formwork body 7, each of the radial supports 8a,
8b and the connecting rods 9, 9 form a triangular continuous support structure with good stability, and each support column 81i
Due to its radial arrangement, the L18b intersects with the form body 7 at a right angle or close to a right angle compared to only upright columns, so that the force against the horizontal load is increased. In particular, at the beginning of pouring the concrete 5, an abnormal situation occurs in which a large horizontal load is applied only to the ends of the form body 7, and the form body 7 tends to bend strongly upward; In response to the load condition, the formwork 7 is opposed to the leg structure 1 or the base 6 by the restraining force of the tensile material 11, etc., in cooperation with the respective supports 8a and 8b.

"Effects of the Invention" As explained above, the formwork device of the present invention can be applied to an arch-shaped formwork constructed between existing leg structures, with a required distance between both ends of the formwork. The upper ends of each pillar are tied together, the lower ends of each pillar are supported near the center of the base between both leg structures, the upper ends of each pillar are connected to each other by a connecting rod, and the outer ends are connected together. Since the upper end of a certain column is fixed to the base or existing leg structure, the arch-shaped formwork can be constructed using the commonly used buffing material and sheathing board. By applying a simple structure in combination with the above, it is possible to form a strong formwork device for arch concrete construction using only the restraining means of the supports and the formwork body, and the formwork is lightweight and It is easy to use, has good work efficiency, can significantly reduce costs, and has many excellent effects.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of the device of the present invention. FIG. 2 is an explanatory diagram of the construction of arch concrete formwork, and FIG. 3 is a front view showing a conventional formwork apparatus. 1... Leg structure 4... Outer formwork 5.
...Concrete 6...Foundation 7...
・・・Archid formwork body

Claims (1)

[Claims] The upper ends of the pillars are tied to the arch-shaped formwork constructed between the existing leg structures, with a required interval between both ends, and the lower ends of each of the pillars are connected to the arch-shaped formwork constructed between the existing leg structures. Support near the center of the foundation between the buildings, connect the upper ends of each pillar with a connecting rod, and further restrain the upper ends of the outer ends of the pillars on the foundation or existing leg structure. Formwork equipment for arch concrete, which is characterized by: