JP2553348B2 - Form support for arch concrete construction - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of use) The present invention relates to a support for a formwork applied to the construction of arch concrete in an arch bridge or the like.

(Prior Art) When constructing a concrete structure such as an arch bridge, the construction work, especially the formwork support facility required for the construction of arched concrete between bridge piers (including abutments) becomes a major problem. It is easy if it can be done only by supporting the formwork with a large number of vertical columns like the support work of a horizontal slab, but it is not as easy as a horizontal slab because it has a sloped part in the case of an arch. . Since the concrete load applied to the formwork acts in the direction perpendicular to the formwork surface in any case, the arch concrete on the slope part applies not only the vertical load but also the horizontal load to the support work. . Since the support pillars are usually erected vertically, the arch support must have a structure that can withstand the horizontal direction. This inevitably results in a truss structure or something similar, and the support work becomes a heavy structure and the construction is complicated. If the arch shape of the arch concrete changes, the supporting work must be manufactured and assembled according to the shape each time, which requires a lot of time and a lot of materials and enormous cost.

The present inventor, in view of such an actual situation, has found that Japanese Patent Application No. 60-1392
With the invention of No. 97 etc., we have been developing economical and easy-to-construct support for arch concrete formwork. According to the supporting work of this invention, a triangular unit supporting element is formed by the main rod and the pair of side rods, and a large number of them are pin-coupled to each other at the end of the main rod, and at the connecting portions of the both side rods are sub-subtracted from each other. With a structure that is connected by a rod, the support of the truss structure that supports the form is strong and easy to assemble and disassemble, and the arch shape can be changed simply by changing the length of the auxiliary rod. Therefore, it is possible to apply it again to the construction of arch concrete with various sizes and arch shapes, and it is possible to make a great improvement over the whole construction such as material saving and simplification of construction. is what happened.

(Problems to be solved by the invention) By the way, in a temporary structure such as a support work,
It is economically important to use a standardized material that can be used as a member that constitutes it.

The supporting work according to the present invention is also designed so that it can be widely applied to arch concretes of different spans by combining unit supporting elements of the same structure which are unitized. However, if a supporting structure having an arch span longer than the design standard range is to be constructed, the unit supporting elements up to that point will have insufficient strength and rigidity. Therefore, also in the support work of the above invention, there is a natural limit to the width of adaptation to the size of the span length. The present invention has been made for the purpose of expanding the range of application in the support work of the method of combining the above-mentioned unit support elements.

The supporting work of the invention applies an arch frame structure to the arch concrete, but the supporting structure of the arch structure is a state of receiving a total load (concrete load) due to the characteristics of its structural form. At, the overall deformation is very small and extremely stable, but when subjected to a partial load, wavy deformation occurs. For example, when concrete loads are applied only to both lower parts of the supporting work, the lower part is displaced inward and the arch upper part is lifted upward. When a load is applied only to the upper part, the upper part sinks and the lower part bulges outward. Therefore, if the method with the best workability, that is, sequentially piling up from below, is adopted for the placement of arch concrete, the support work will show a wavy deformation during the concrete placement process, which will result in various changes to the concrete. Unfavorable effects of. When the span length of the arch exceeds a certain limit and becomes large, this wavy deformation becomes unacceptable, and the standardized unit combination lacks rigidity and strength, and another measure is required.

According to the present invention, as a truss for arch support work, the structure of the standardized unit combination method of the above-mentioned invention, which is capable of being overturned, is left as it is, and a simple tension member (reinforcing tension member) is additionally provided inside the auxiliary rod. By utilizing the effect of increasing the height of the concrete, the strength and rigidity are increased, and the standardized unit application range is expanded to arches with long spans, resulting in easy-to-handle arch concrete construction. It aims to provide formwork support more economically.

(Means for Solving Problems) The structure of the present invention will be described with reference to the drawings corresponding to the embodiments. According to the present invention, the main rod 11 and a pair of side rods 12 and 12 are combined to form a triangle. A large number of the supporting elements 15 formed on each of the main rods 11 are connected to each other by pin couplings 17 at the ends of the main rods 11, and the connecting portions of the two side rods 12 and 12 of each supporting element 15 are formed shorter than the main rod 11. Are connected to each other by the auxiliary rods 18 and 18 to form an arch-shaped frame structure 10. Also, in the middle portions of both halves of the connected auxiliary rods 18 and 18 toward the center of the arch. Auxiliary rods 5 and 5 are provided in a protruding manner, and the projecting end portions thereof are connected to the end connecting portions 19 and 19 of the auxiliary rods 18 and 18 and the central portion of the arch by the auxiliary rods 16 and 16 to provide reinforcing tension members 7 and The outer ends of the main rods 11, 11 at both ends of the arch-shaped frame structure 10 are supported by existing structures such as piers 1, 1.

(Example) Hereinafter, an example of the present invention will be described with reference to Figs.

In the figure, 1 and 1 are leg structures constructed at a predetermined interval before placing arch concrete 8; 2 is an arch form frame laid between the leg structures; 10 is the arch The arch-shaped frame 2 is an arch-shaped frame structure that supports the mold, and the arch-shaped frame 2 is an arch-shaped flap material 3
Are arranged in parallel and are appropriately connected by a lateral flap material (not shown), and a weir plate 4 is attached to the outside of the flap material 3.

The arched frame structure 10 includes side rods 12, 12 on both ends of the main rod 11.
One end of each of these is bound by 13, 13 (see FIG. 2), and the other ends thereof are bound by a coupling plate 14 to form a supporting element 15 which is framed in a triangle. As a constituent member, a large number of them are connected to each other at the ends of the main rods 11 and 11 by a pin 17
, And the connecting plates 14, 14 of each supporting element 15 are connected 19 to each other by a sub-rod 16 shorter than the main rod 11 to form an overall arch-shaped truss structure. The sub-rod 16 may be attached to the joint plate 14 by a pin joint 19, but an auxiliary plate (not shown) may be pin-joined to the joint plate 14 so that the sub-rods 16 are fixed to the plate by welding. You may

The size of the curve formed by this arch-shaped frame structure 10 is
It will be determined by the length of the auxiliary rod 16. Therefore, the arch-shaped frame structure 10 can be flexibly changed by changing only the length of the sub-rod 16, and the arch length can be freely increased / decreased in 15 units of each supporting element. , It will also be possible to accommodate the construction of an arched frame that bends in a complicated manner.

Then, the auxiliary rods 5 and 5 are attached to the connecting plates 14 and 14 at the respective intermediate portions of both halves of the supporting elements 15 and 15 connected.
Connecting plates 14 and 14 of supporting elements 15 and 15 which are provided so as to project toward the center of the arc of the arch-shaped frame structure 10 and which are the connecting portions of the sub-rods 18 at both ends from the projecting end portions, To the connecting plates 14 and 14 of the supporting elements 15 and 15 in the central portion, the respective end portions of the reinforcing tension members 7 and 7 having the length adjusting tools 6 and 6 such as turnbuckles are connected respectively. It is stretched.

Further, the formwork 2 is provided at both ends of the outer surface of the main rod 11 of the supporting element 15.
There is provided a seat body 22 on which a contact plate 21 for directly supporting the flap material 3 is placed. The contact plate 21 is formed by stacking wedge plates 21a and 21b on top of each other, and the height of the contact plate 21, that is, the distance between the main rod 11 and the flap 3 can be adjusted by increasing or decreasing the overlapping margin. Then, connecting bolts 23 are provided at appropriate places on the flutter material 3 so as to be engaged with the main rod 11, so that it is easy to attach the formwork 2 to the support and remove the formwork 2 after placing concrete. I can do it.

The arch support structure having the above-mentioned structure is provided with support elements 15, 15 at both ends.
The end portions of the main rods 11 and 11 are fixed to the brackets 24 and 24 fixed to the bridge piers 1 and 1 or other existing structures with pins 25 and 25 to be constructed. The work on the frame is the same as for general truss structures, and this support work is installed in multiple rows in the depth direction of the arch concrete to be constructed at the required intervals and they are connected to each other with the required members. .

The formwork 2 is erected on the frame arch support. That is, the flap material 3 is applied to the outside of the arch support work 21
It is mounted on the main rod 11 with bolts 23, and the weir plate 4 is attached to the outer surface of the flap material 3.

At this time, the arc of the flap material 3 that determines the arc of the mold can be appropriately adjusted by adjusting the height of the contact plate 21 having a wedge structure.

After erection of the formwork 2, the auxiliary formwork 20 is installed between the end of the formwork 2 and the bridge pier 1, the outer formwork 9 is erected, and the concrete 8 is placed between both formworks 2 and 9. To do. Concrete 8
After hardening, remove the outer form 9 and the auxiliary form 20, then remove the seat plates 21 and 21, tighten the nuts of the connecting bolts 23, and pull the flap 3 toward the main rod 11. If done, the mold 2 will be peeled off from the concrete 8.

After the construction of the arch concrete 8 is completed, it is usual to dismantle and remove the formwork 2 and the supporting works, but in this case,
The bracket 24 to which the main rod 11 is attached is not fixed to the pier 1, a long rail is laid in the pier 1 in the depth direction, and a moving vehicle is attached to the end of the main rod 11 for arch support. If the mold 2 is moved along the rail, it can be moved to the next construction site without disassembling the mold 2 in a state of being separated from the concrete 8.

In the arch support work of the present invention, when the concrete 8 is cast, a compressive force is applied to the main rods 11 and 11, and a tensile force mainly acts on the auxiliary rods 18 and 18, but the tensile force is assisted. It is also shared by the reinforcing tension member 7 via the rod 5. Therefore, both the auxiliary rod 18 and the reinforcing tension member 7 oppose the tensile force, and an extremely high rigidity is obtained in synergy with the effect of increasing the height of the truss. It is desirable to adjust the degree of tension of the reinforcement tensioning member 7 by operating the turnbuckle 6 so that the stress distribution between the auxiliary rod 18 and the reinforcement tensioning member 7 exactly matches the design value.

FIG. 3 shows another embodiment in which the reinforcing tension members 7 are provided. As in the above-described embodiment, the end crossing shape of the reinforcing tension members 7, 7 on both sides in the central portion of the arch support structure 10 is crossed. Alternatively, as shown in the drawing, the ends of the reinforcing tension members 7, 7 on both sides can be bound to the joining plates 14, 14 at the top end which are not connected by the auxiliary rod 18.

In addition, the reinforcing tension member 7 is not limited to the linear member as shown in the drawing, and the auxiliary rod 5 can be formed by using a rod member that can resist the compressive stress.
You may make it a truss structure. Further, the means for connecting the arch support 10 and the mold 2 is not limited to the above embodiment, and for example, the butter member 3 of the mold 2 is connected to the bolt provided on the main rod 11 so as to be movable back and forth. You may do it.

(Effects of the Invention) As described above, according to the present invention, the unit supporting element is formed by the main rod and the pair of side rods, and a large number of them are pin-coupled to each other at the end of the main rod, and both sides are connected. Since the arch supports are constructed by connecting the rods to each other at the connecting part of the rods by the auxiliary rods, and further by reinforcing reinforcements inside the arcs of the connected auxiliary rods, the support of the truss structure supporting the formwork is constructed. The work can be done easily and easily by disassembling and assembling, and the shape of the arch can be changed only by changing the lengths of the auxiliary rod and the reinforcing tension material. Therefore, the construction of arch concrete of different sizes is possible. It is possible to apply it again, and it is possible to save the material and save labor.

In addition, the reinforcement tensioning material has a reinforcing effect by increasing the height of the arch truss, and the effect of suppressing the wavy deformation of the support work during the concrete placing process when the arch span is large is remarkable, and the standardized support The application range of the engineering unit can be expanded to a long span, and as a result, the economical efficiency of arch support work can greatly reduce the high-cost construction cost, and many other excellent effects are exhibited.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a construction mode using a supporting work according to an embodiment of the present invention, FIG. 2 is an enlarged side view showing an essential part of the supporting work, and FIG. 3 is another embodiment of the same. It is a sectional side view shown. 1 ... Bridge pier, 2 ... Arched formwork 5 ... Auxiliary rod, 7 ... Reinforcing tension material 8 ... Concrete, 9 ... Outer formwork 10 ... Arch support, 11 ... Main rod 12 ... Side rod, 15 …… Unit support element 17 …… Pin, 18 …… Sub rod 20 …… Auxiliary formwork

Claims (1)

(57) [Claims] 1. A large number of supporting elements formed in a triangle by connecting a main rod and a pair of side rods to each other are connected to each other by pin connection at the ends of each main rod, and at the same time, on both side rods of each supporting element. The connecting rods are connected to each other by the auxiliary rods formed shorter than the main rods to form an arch-shaped frame structure, and the center of the arch is formed in the middle part of each half of the arches by the connected auxiliary rods. Auxiliary rods projecting in the direction, and the projecting end of the auxiliary rod is joined to the end connecting part of the sub rod and the center of the arch by the sub rod to provide a reinforcing tension member. Form support for arch concrete construction, characterized in that the outer end of the rod is supported by existing structures such as bridge piers.