JPS63226460A - Mold frame timbering for executing 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 (Industrial Field of Application) The present invention relates to formwork support applied to the construction of arch concrete in arch bridges and the like.

(Prior Art) When constructing a concrete structure such as an arch bridge, a major problem arises in terms of its construction, especially the formwork support facilities required for constructing the arch-shaped concrete between the piers (including the abutments).

It would be easy if it could be done by simply supporting the formwork with a large number of vertical supports, like shoring for horizontal slabs, but
In the case of an arch-shaped slab, it has a sloped surface, so it is not as simple as a horizontal slab. In any case, the concrete load applied to the formwork acts in a direction perpendicular to the formwork surface, so arch concrete on a slope will apply a load not only vertically but also horizontally to the shoring. .

Since shoring columns are normally erected vertically, arch shoring requires the addition of horizontal support structures. This inevitably results in a truss structure or something similar, and the shoring becomes a heavy structure, making construction complicated.

If the shape of the concrete arch changes, the shoring must be manufactured and assembled to match the shape each time, which requires a lot of time, a lot of materials, and a huge amount of expense.

In view of the actual situation, the present inventor has made a patent application filed in 1986-13
No. 9297 and other inventions have led to the development of economical and easy-to-implement arch concrete formwork supports. In the shoring of the present invention, a triangular unit support element is formed by a main rod and a pair of side rods, a large number of which are connected to each other with pins at the ends of the main rod, and the supporting rods are connected to each other at the connecting portions of both side rods. The structure is connected by rods, and the truss structure supporting the formwork is strong and easy to assemble and dismantle, and the shape of the arch can be changed by simply changing the length of the secondary rods. Therefore, it is possible to apply the method six times to the construction of concrete arches of various sizes and arch shapes, making it possible to make significant improvements in overall construction, such as saving on materials and simplifying construction. is what happened.

(Problem to be solved by the invention) By the way, for temporary structures such as shoring, it is economically important to use standardized members that can be used for other purposes. .

The shoring according to the invention is also designed to be widely applicable to large and small concrete arches with different spans by combining unit supporting elements of the same configuration. However, when constructing a support with a span considerably longer than the design standard, the strength of the existing unit support elements becomes insufficient. Therefore, even in the shoring of the invention, there is a natural limit to the extent to which it can be adapted to the size of the span length.

The present invention was made for the purpose of greatly expanding the scope of application of the shoring system in which the above-mentioned unit support elements are combined. Focusing on the fact that compressive stress (compressive stress) acts on the main rod, we decided to make the main rod a combination of upper and lower two-stage rods, doubling the strength of the main rod, and increasing the applicable range of formwork support using unit support elements. The aim is to spread the word widely.

If the main rod is constructed in a two-stage combination, there will be a large error in the overall length of both the upper and lower rods. This is caused by manufacturing errors and assembly errors in each main rod, errors in the height of the base on which the main rod's support part is mounted, and errors in both sides when deformed (compressive strain) under the load of concrete. Due to the difference in the amount of deformation of the main rods, an imbalance occurs in the stress that the two main rods receive. This is a big problem, and in extreme cases, for example, the upper rod (reinforced main rod) may bear most of the stress, while the lower rod (main rod) bears almost no stress. . The present invention aims to solve this problem and provide a standardized and economical formwork support for arch concrete construction that has a wide range of applications.

(Means for Solving the Problems) The configuration of the present invention will be explained with reference to FIGS. 1 and 2 corresponding to embodiments.
A large number of support elements 15 formed into a triangle by combining the
1 each main rod for each other! are connected by a bottle joint I7 at the end of each supporting element 15, and reinforcing main rods 22 are connected to the outside of each main rod If in each supporting element 15, and linked to each main rod 11 to form a semi-arched truss. Forming a structure, the pair 10a and lOb are pin-coupled at their top ends via end connecting rods 31, 31 that connect the respective end portions of their main rods 11 and reinforcing main rods 22. 30, and the main rods 11 and reinforcing main rods 22 forming a part of each half-arch truss structure 10a, 10b are separated by the spacing member 2.
0, each half-arch truss structure 10a
, 10b, the center portions of the terminal connecting rods 18.18 that connect the main rods 11 and the reinforcing main rods 22 at the lower ends of each of the rods 10b are connected to the brackets 24.24 provided on the pier 1.1 by means of bins 26°26.
It is characterized by the fact that

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 and 2.

In the figure, l and I are leg structures constructed at predetermined intervals before placing the arch concrete 8, 2 is an arch formwork constructed between these leg structures, and IO is the arch. It is an arch-shaped shoring that supports the formwork, and the arch-shaped formwork 2 is made of butter material 3 formed in an arch shape.
A large number of these are arranged in parallel and connected as appropriate by horizontal butterfly members (not shown), and a weir plate 4 is attached to the outside of the butterfly members 3.

The arch-shaped shoring 10 has side rods 12 at both ends of the main rod 11.
, 12 are tied together at one end 13.13, and their other ends are tied together via a coupling plate 14 to construct a triangular supporting element! 5, which are used as unitary components, and a large number of them are connected to each other by pins I7 at the ends of the main rods 11.11, and the connecting play of each supporting element 15.15), 14.14 is They are connected by a sub-rod 16 shorter than the main rod 11, forming a semi-arge-like truss structure as a whole. The installation of this sub-rod 16 is done by connecting plate I.
Alternatively, an auxiliary plate (not shown) may be coupled to the coupling plate 14 using a vial connection 19, and an auxiliary rod may be attached to this plate. 6 may be fixed by welding. The pair of semi-arched truss structures 10a and Job are then joined together at their ends to form an arch support lO, as will be described later.

The size of the curvature formed by this arch support lO will be determined by the length of the sub-rod 6. Therefore, the degree of curvature of the arch support 10 can be freely changed by changing only the length of the sub-rod 16.
Furthermore, the degree of curvature can be freely increased or decreased in units of 15 for each supporting element, making it possible to cope with the construction of arch formwork with complex curvature.

Additionally, a truss structure 10a formed on the half arch
, 10b, reinforcing main rods 22, 22 formed in the same manner as the main rods 11 are arranged at required intervals on the outside of the main rods 11, 11 of each support element 15, and the main rods 11, 11 One end of the connecting rods 21, 21 of a required length is pivotally connected to the mutual connection point via a pin I7, and each end of the reinforcing main rods 22, 22 is pivotally connected to the other end, so that the connecting rod 21 and The reinforcing main rods 22, 22 are connected to each other by pins 23.

The terminal portions of the reinforcing main rods 22, 22 located on the respective top end sides of the respective truss structures 10a, 10b are dogleg-shaped top end connecting rods with one end pivotally connected to the terminal portion of the main rod 11 by a pin 32. It is pivotally connected to the other end of 31 by a pin 33. In addition, the main rod 1 located at the lower end side of each truss structure 10a, lOb
1 and each end portion of the auxiliary main rod 22 are connected to both ends of a terminal connecting rod 18 formed wider than the connecting rod 21 by pins 25 and 25.

The half arch support 10a configured in this way.

10b are the end connecting rods 31.3 on the top end sides of each other.
1 are joined and connected by pins 30, thereby forming a shoring lO made of an arch-shaped truss frame as a whole. This arch support lO is constructed by fixing the center portions of each terminal link 18.18 to brackets 24.24 fixed to the pier 1.1 using pins 26.26.

As mentioned above, each main rod 11.11 and reinforcing main rods 22, 22 of the arch support 10 are connected to the connecting rod 21.21 and the top connecting rod 31.
, 31 and terminal links 18 and 18, they are linked together. In this case, since the lengths of the main rod 11 and the reinforced main rod 22 are almost the same, there will be some deviation in the length direction between the main rod 11 and the reinforced main rod 22; , the connecting rods 21, 21 and the terminal connecting rod 18 as shown in the figure.
．． It can be adapted by changing the slope and length of 18.

In addition, if the deviation is large, it can be conveniently formed by inserting an appropriate number of reinforcing main rods of irregularly shaped tools into appropriate positions.

In this way, the arch support ■0 has the reinforcing main rods 22, 22 connected to each other via the connecting rods 21.2I and 31. , 31 and the terminal connecting rods 18.degree. 18, so that by changing the lengths of the sub-rods 16, 16, the degree of curvature of the arch can be changed to some extent. Even if the degree of curvature is changed significantly, it has excellent versatility as it can be handled by changing the length of the sub-rod 16゜16 and by changing the lengths of the small number of reinforcing main rods 22 and connecting rods 21, 21. ing. Note that with only the above configuration, the main rods 11, 11 and the reinforcing main rods 22, 22 as a whole move in parallel and are not stable, so a structure is provided in which the spacing member 20 stops the parallel movement of both main rods. That is, each half-arch truss structure 10a, 1
A rod-shaped spacing member 20 is attached to one end of the pair of main rods II and the other end of the auxiliary main rod 22 at the top or middle part of 0b.
．． 20 are passed to each other, tied together with bottles 17 and 33, and constructed.

Note that the spacing member 20 is constructed not only by the means shown in the drawings but also by any means that can relatively fix the main rod 11 and the auxiliary main rod 22.

A plurality of arch supports 1O having the above configuration are installed at required intervals in the depth direction of the arch concrete to be constructed, and each of these supports is a side beam! 2, the main rod 13 and the reinforcing main rod 22 are three-dimensionally connected to each other by depth direction connecting rods (not shown) to form the entire shoring structure.

Screw rods 27 and 27 are attached to the reinforcing main rods 22 of each supporting element 15 by penetrating through the reinforcing main rods 22, and a pair of nuts 2 are screwed onto the screw rods 27 with the reinforcing main rods 22 in between.
It is fixed by tightening 8.28,
By adjusting the screwing relationship position with this nut 28, the length of protrusion from the reinforcing main rod 22 can be adjusted.

The formwork 2 is constructed on a constructed arch support. That is, the butterfly material 3 is placed on the outside of the reinforcing main rods 22, 22 of the arch support, and the pin 7 is inserted into the pre-provided bottle hole of the butterfly material 3 and the bottle hole at the end of the threaded rod 27.
It is fixed to the reinforcing main rod 22 via this threaded rod 27, and the weir plate 4 is attached to the outer surface of the butterfly material 3. At this time, the position and arc of the formwork can be adjusted as appropriate by adjusting the protruding length of the threaded rod 27 with respect to the reinforcing main rod 22.

After the formwork 2 is erected, the auxiliary formwork 6 is installed between the end of the formwork 2 and the pier I, the outer formwork 5 is erected, and concrete 8 is poured between both formworks 2.5. do. concrete 8
After hardening, remove the outer formwork 5 and the auxiliary formwork 6, then loosen one nut 28 and tighten the other to shorten the protruding length of the threaded rod 27. The frame 2 will be drawn towards the reinforcing main rods 22, thereby causing the formwork 2 to be separated from the concrete 8.

After the construction of the arch concrete 8 is completed, the formwork 2 and the support IO are normally dismantled and removed.
is not fixed to the pier 1, and a long rail is laid in the depth direction on the pier I. Moving wheels are attached to the ends of the main rods 11, and the arch support lO is moved along the rails. In this way, the formwork 2 can be moved to the next construction site without being dismantled with the formwork 2 separated from the concrete 8.

(Effects of the Invention) As explained above, according to the present invention, a main rod and a pair of side rods form a unit support element, a large number of which are connected to each other at the end of the main rod, and The rods are connected to each other by sub-rods at the connecting portions, and reinforcing main rods are arranged outside the main rods of each supporting element in parallel with the main rods, so that the reinforcing main rods are connected to each other and the main rods to each other. Connected in a link shape by
Since half-arched supports are formed and a pair of them are connected to each other at the top end to form an arched support, the truss-structured support supporting the formwork can be made strong and easy to assemble and dismantle. The shape of the arch can be changed mainly by changing the length of the secondary rods, and therefore it can be applied repeatedly to the construction of arch concrete of various sizes, resulting in material savings and savings. Labor saving can be achieved.

In addition, the main rod, which receives most of the stress, is additionally connected to a reinforcing main rod via a connecting rod, thereby doubling its strength.

The connected reinforcing main rods in the arch support are linked to the main rods connected by the connecting rods, the top connecting rods, and the terminal connecting rods, and are attached to the brackets provided on the piers at the center of the connecting rods. In addition, since the pair of main and auxiliary main bars in each half-arch structure are fixed by the spacing member, relative translation between the main and reinforcing main bars is suppressed, resulting in stability. At the same time, there is an imbalance in the stress applied to both main rods due to errors in the length of both main rods after assembly, errors in the height of the mounting base of the support at both ends of the main rod, and differences in shrinkage caused by the load of arch concrete. is eliminated, and the mechanism is changed so that both main rods always share the stress equally, making it extremely reliable that the design calculated stress and the actual stress of the shoring accurately match. The practical implementation of the configuration becomes possible, and the scope of application of standardized unit support elements is thus greatly expanded. As a result, arch shoring can be constructed by reusing and combining almost the same parts for arch spans of various sizes, which significantly increases the economic efficiency of arch shoring and greatly reduces construction costs. It has many excellent effects such as saving money.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a construction mode using a shoring according to an embodiment of the present invention, and FIG. 2 is an enlarged side view showing the main part of the shoring. 1... Pier 2... Arch formwork 5... Outer formwork 6... Auxiliary formwork 8... Concrete IO... Arch shoring IQ
a, 10b...Semi-arched truss structure 11...Main rod 12...Side rod I5...Unit supporting element IO...Sub-rod I7...
Pin 18... Terminal link 20... Spacing retaining member
2I... Continuous rod 22... Reinforcement main rod 23... Pin 24... Bracket 25... Pin 27...
Screw rod 28...Nut 31...Top connecting rod Patent applicant Okabe Co., Ltd. (1 other person)

Claims (1)

[Claims] A large number of support elements formed into a triangular shape by joining a main rod and a pair of side rods are connected to each other by pin connections at the ends of each main rod, and further, a number of supporting elements are connected to each other by pin connections at the ends of each main rod, and A half-arch truss structure is formed by connecting reinforcing main rods and linking them to each main rod. Pin-coupled via an end link connecting the distal ends, and
Some pairs of main rods and reinforcing main rods in each half-arch truss structure are fixed by a spacing member, and the main rods and reinforcing main rods at the lower end of each half-arch truss structure are fixed. A formwork support for arch concrete construction, characterized in that the central part of the terminal connecting rod is connected with a pin to the bracket provided on the pier.