JP3306865B2 - Method of manufacturing precast concrete arched unit plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an arch unit plate forming an arch structure.

[0002]

Conventionally, as an arch-shaped hollow structure, Japanese Utility Model Application Laid-Open No. 59-192911 discloses three types.
There is a precast concrete snow shelter in which a hinge arch type concrete block of unit length is connected and the block group is tensioned with a PC steel material (the scope of claims in the Japanese Utility Model Registration). This shelter is made of a highly reliable precast block member, mainly composed of a 3-hinge concrete arch that does not generate bending moment at the arch member end (Microfilm, page 2, lines 10-13)
Thus, there is known a structure in which a three-hinged arch-shaped structure is buried in the ground to form a passage as an arch culvert.

FIG. 19 is an explanatory view of an arch-shaped structure having a three-hinge structure. The joints at the tops of the left and right precast plates 101, 101 are smoothened by hinges 102, and the lower portions of the precast plates 101, 101 are hinged. 103 and 103 are joined to the substructure 104. The arched hollow structure having such a three-hinged structure is a statically-determined structure. When an evenly distributed load P is applied to the arched hollow structure by earth and sand, and an equally distributed load Q is applied to the side surface thereof, the hinges 102 and 103 are used. Instead of generating a bending moment at a certain joint, the bending moment is maximized substantially at the center of each member, and the strength of the entire structure depends on the strength of the weakest member. Further, a biased load is applied to the structure, for example, the precast plate 10 on the left side in the figure.
When a load is applied to 1, the bending moment in the left precast plate 101 decreases, but the right precast plate 10
The bending moment at 1 is increased, and thus the three hinge structure has a disadvantage against an eccentric load.

In Japanese Utility Model Laid-Open No. 59-192911, the arches are connected by connecting bolts (Microfilm, page 3, lines 13 to 14 and FIG. 3). In the publications, it is described that the pieces of the segments are joined and fixed by bending bolts, but all of them are pin connections.

Incidentally, the above-mentioned Japanese Utility Model Application Laid-Open No. Sho 59-192911.
In the gazette of Japanese Patent Application Laid-Open Publication No. H11-27173, the arched structure is divided into two parts to be assembled so that transportation and installation work are facilitated. However, if the width of the inside of the arched structure changes, the radius of the arch changes according to the width, so formwork of each shape must be prepared, and the cost of the formwork in the production cost becomes large. There is.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of manufacturing an arch-shaped unit plate in which a molding frame can be shared and a product corresponding to a width can be easily manufactured.

[0007]

Means for Solving the Problems The present invention according to claim 1 comprises a pair of
When the joining surfaces at the top of the arched unit plate are
Together, the tops are joined together to form an arched structure ,
Concrete is cast on the formwork of the arched unit plate.
In the method for manufacturing a precast concrete arch-shaped unit plate to be installed and molded, a duct for inserting a joining member is provided at the top of the arch-shaped unit plate, and the duct is provided .
The mold is open at the joint surface, and the molding form is
A joint surface molding part for molding a mating surface, wherein the common molding
A plurality of arch-type unit plates in which the joint surfaces are parallel to each other by adjusting the dimension in the width direction of the top portion in accordance with the width of the arch-shaped structure by changing the joint surface molding portion in the forming frame. This is a manufacturing method for molding.

According to the first aspect of the present invention, by adjusting the size of the top, the width of the arch-shaped structure to which the arch-shaped unit plates are joined can be adjusted. In manufacturing, the joining surface of the top is molded. Since only the form plates to be formed need to be changed, it is possible to mold an arch-shaped unit plate that forms arch-shaped structures having different widths by using a common form.

Further, according to the invention of claim 2, the duct is
When the arch-shaped structure is substantially semicircular, the manufacturing method is arranged below the joint surface of the top portion.

According to the second aspect of the present invention, the PC steel bar resists the tensile force generated at the joint by the load after installation, so that the joint can be firmly joined. Can manufacture boards.

Further, according to a third aspect of the present invention, there is provided a method of manufacturing a semiconductor device, wherein a thick portion is provided on an outer surface side of the top portion, and the duct linearly connects a joining surface of the top portion and an outer surface of the top portion. It is.

According to the structure of the third aspect, even if the top is shortened for size adjustment, the duct can be made relatively long due to the thick portion of the outer surface of the top.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 12 show a first embodiment of the present invention. As shown in FIG. 1, a basic arch-shaped unit plate 1 made of precast concrete is made of high-strength concrete 2 and has an unpounded PC steel material in its bending direction. 3 and the PC steel material 3 is the arch-shaped unit plate 1
As shown in FIG. 5, an embedding fixing device 3A is fixed to the top side of the base plate, and the unpounded PC steel material 3 is tensioned to apply a tension, as shown in FIG. The image is fixed by the fixing device 3B. The basic arch-shaped unit plate 1 is bent in a fold line at bending positions 4 provided at substantially equal intervals, and has a large number of flat surfaces 5N and 5G on the inner surface and the outer surface. 5
.. Form a continuous bent surface as the inner angle θN of N, 5N, and a line connecting the inner surfaces at the bent position 4 in the basic arched unit plate 1 is an arc. The adjacent flat surfaces 5G on the outer surface of the basic arch-shaped unit plate 1 also form a continuous bent surface. In addition, the basic arched unit plate 1
The top portion 6 is formed with a thick portion 7 that makes the top portion 6 thicker than the lower portion, and an upper surface 7U of the thick portion 7 is formed to be nearly horizontal and flat. The arch-shaped unit plate 1 is formed so as to become gradually thicker toward the side. That is, as shown in FIG. 2, the thicknesses T1, T2, T3, and T4 at the bending position are T1 <T2 <T3 <T4.
In this example, T1 is 300 mm, T2 is 330 mm, T3 is 360 mm, and T4 is 390 mm. In addition, the thickness of the joining surface 9 is equal to T4, and the thickness of the lower part of the bending position 4 described with the symbol T1 is equal to T1. A duct 8 is formed at the top 6, and one end of the duct 8 is opened at the joining surface 9 of the top 6, and the other end is opened at a step 10 formed on the outer surface side at the end of the thick portion 7. ing. The duct 8 is arranged on the lower side of the joint surface 9 of the basic arched unit plate 1. Further, a plurality of ducts 11 in the longitudinal direction are formed in the basic arched unit plate 1. In addition, a reinforcing bar (not shown) is embedded in the basic arched unit plate 1.

[0014] Then, butt joint surfaces 9, 9 of the top portions of the pair of the base arched unit plate 1,1, inserting the P C steel bar 12 Ru joining member other duct 8, in the step portion 10,
Insert the anchor plate 13 into the end of the PC rod 12
The tension is applied to the steel bar 12 and the nut 14 is fastened and fixed to the threaded portion formed at the end of the PC steel bar 12 so that the tops 6 and 6 of the basic arched unit plates 1 and 1 are mutually connected. Rigidly joined to form an arched structure 15. Further, the lateral tightening PC steel material 16 is inserted into the ducts 11 of the arched structures 15, 15...

The thick portion 7 is provided on the arch-shaped unit plate 1.
The upper surface 7U of the upper surface 7U is a flat surface that forms a gradual or inclined horizontal or nearly horizontal direction from the bonding surface 9 to the outside in the width direction. Forms a corner 17 and is inclined upward from the corner 17 to the outside.
18 are provided. Further, the step portion 10 is provided at the corner portion 17.
And a vertical surface which is a locking surface on which the nut 14 is locked.
19 and a lateral bottom surface 20.

The lower part of the arched structure 15 is a substructure.
The substructure 21 in this example is made of reinforced concrete made of cast-in-place concrete, and has a flat plate portion 22 having a substantially constant thickness and cradle portions 23 provided on both sides of the flat plate portion 22.
23, and the upper part of the cradle part 23 has the arched structure.
A recess 24 into which the lower part of the 15 is inserted is formed. And
Insert the lower part of the arched structure 15 into the recess 24,
And the arched structure 15 is rigidly joined to the substructure 21. An arch culvert 25 as a hollow structure is formed by the substructure 21 connecting the arched structure 15 and a lower portion of the arched structure 15. In the figure, 26 is a road surface provided on the substructure 21 and 27 is a sidewalk. Then, in the arched structure 15 using the basic arched unit plate 1, the arched unit plates 1 on both sides at the joint surfaces 9, 9.
The inner angle θ of the top formed by the inner surfaces 5N, 5N is equal to the other inner angle θN, the radius R of the arched structure 15 is, for example, 6 meters, the inner space width H is 12 meters, and the pedestal portion is formed.
The width, which is the inside dimension of 23, 23, is 11.1 meters.

In assembling the arch-shaped unit plates 1 and 1, since the top surface of the arch-shaped unit plates 1 and 1 is flat, a joining operation or the like using the PC steel rod 12 can be easily performed. In addition, the thick portion 7 is formed, the step 10 is formed on the outer surface of the thick portion 7, and the horizontal duct 11 is formed between the step 10 and the joint surface 9, so that it is extended to the arch structure. The length of the duct 11 can be made relatively long without providing any portion, and the necessary tension can be introduced by using the relatively long PC steel rod 12, so that the joining surfaces 9, 9
Can be firmly and rigidly contacted. Further, since both ends of the PC steel bar 12 are fixed to the step portion 10 of the thick portion 7, the position of the PC steel bar 12 on the joint surface 9 can be arranged on the inner surface side.

When the arch-shaped culvert 25 thus formed is buried, a load is applied. This will be described with reference to the drawing of FIG. 4. FIG. 4 shows that an evenly distributed load P is applied to the arched culvert 25 formed from the basic arched unit plate 1 by earth and sand, and an equally distributed load Q is applied to a side surface thereof. When these loads P and Q are applied, a bending moment M is generated in the arched culvert 25 as shown in FIG. In this specification, a positive bending moment M is a moment in a direction in which the member is concaved,
The negative bending moment M is a moment in a direction that makes the member convex. In this manner, by forming the arch-shaped culvert 25 as an indeterminate structure having three rigid members, positive and negative bending moments M are generated in the arch-shaped unit plate 1, and negative bending moments such as three hinges are generated. Unlike the case where only the bending occurs, the maximum value of the bending moment M generated in the arch-shaped unit plate 1 can be reduced. Also, a positive bending moment M is generated at the top of the arched structure 15, and a tensile force is generated at the lower part of the top 6, that is, a force is generated in the direction of opening the lower part of the joint surfaces 9, 9, but PC steel is used. Since the rod 12 is arranged below the joint surface 9, it is possible to effectively resist the tensile force.

When an unbalanced load is applied to the arched structure 15, for example, when a load greater than one arched unit plate 1 is applied to the other arched unit plate 1, the other arched unit plate 1 becomes negative. However, in the case of three rigid bodies, positive and negative bending moments M are generated with equally distributed loads as shown in FIG. 19, so that even if the negative bending moment M increases due to the unbalanced load, The bending moment M generated by the three hinges is small, which is structurally advantageous against an eccentric load.

As described above, in the arched hollow structure having the arched structure 15 in which the tops 6, 6 of the pair of precast concrete arched unit plates 1, 1 are joined to each other,
A horizontal duct 8 is formed at the top 6 of the arched unit plate 1, and the joining surfaces 9, 9 of the pair of arched unit plates 1, 1 are formed.
Since the straight PC steel rods 12 inserted into the ducts 8 and 8 are rigidly joined by applying tension to each other, the tops 6 and 6 of the arched unit plates 1 and 1 are joined together. Butts, and a straight P
By inserting the C steel rod 12 and tensioning and fixing the PC steel rod 12 to apply tension, the tops 6 and 6 of the arch-shaped unit plates 1 and 1 can be rigidly joined to each other, and approximately half An indeterminate arch can be formed by using the arch-shaped unit plates 1 and 1 obtained by dividing the circular arch, and a precast concrete product can form an arch having a large span, and can be easily transported and constructed. Further, when the hollow structure using the arched structure 15 is subjected to load after installation, the arcuate unit plate 1 occurs positive and negative bending moments and maximum bending moment applied to the arcuate unit plate 1 This is approximately one-half that of the three-hinged structure, the cross section of the member is reduced, and the structure is advantageous even when an eccentric load is applied to the arched structure 15.

The top 6 has a substantially flat upper surface 7U,
Arch-shaped unit plate 1 extending outward from joining surface 9 in the width direction
The upper surface 7U of the top becomes a flat surface that is horizontal or nearly horizontal compared to the arch because the thick portion 7 is formed to make the wall thicker, so that the structure is stable and the flat surface is used. Thus, the joining operation using the PC steel rod 12 can be easily performed.

Further, the thick portion 7 is formed thick on the outer surface side, and the nut 14 serving as a fixing tool of the PC steel rod 12 is locked on the outer surface on the width direction end side of the thick portion 7. A step 10 having a vertical surface 19 is provided, and the duct 8 is opened in the vertical surface 19, so that a PC steel rod 12 to which a tension is applied by fixing a fixing tool such as a nut 14 to the vertical surface 19 is fixed. can do.

Next, a modified example of the arched unit plate will be described. In order to make the width smaller than that of the arched culvert 25, the arched unit plates 1A and 1B in which the top 6 of the basic arched unit plate 1 is shortened. , 1C. These arched unit plates 1A, 1B, 1C
The length of the top portion 6 in the width direction is different from that of the basic arch-shaped unit plate 1, and respective joining surfaces 9 A, 9 B, 9 C are formed in parallel with the joining surface 9. The step 10 is
The arched unit plates 1 and 1A are the same, and the arched unit plates 1B and 1C include a step 10A that is longer in the width direction than the step 10. Also, arched unit plate 1, 1A
The relative height positions of the ducts 8 are the same, and the relative height positions of the ducts 8 of the arched unit plates 1B and 1C are the same. And these arch-shaped unit plates 1A, 1B, 1
C, the inner angles θA, θB, θC of the tops of the arched structures 15A, 15B, 15C, and the basic arched unit plate 1
The relationship with the inner angle θN of the top of the arched structure 15 formed as follows is θ>θA>θB> θC.

As described above, the length of the top 6 in the width direction was changed, and the thickness TS of the joint surface and the center position of the duct 8 were set as shown in Table 1 below. As shown in FIG. 2, in Table 1, Gt and Nt indicate the center positions of the duct 8 from the inner and outer surfaces, respectively. Also, arched structures 15A, 15B, 15 formed by the respective arched unit plates 1A, 1B, 1C.
The inner space widths Ha, Hb, Hc of C are 11 meters, 10 meters, and 9 meters.

[0025]

[Table 1]

As shown in Table 1 above, at the joint surfaces, the PC steel bars 12 are connected to the joint surfaces 9, 9 at the arched structures 15, 15A, 15B.
On the inner surface side of A and 9B, the arched structure 15C, the PC steel rod 12 was on the outer surface side of the joining surface 9C. Then, similarly to the arched structure 15, in the arched structures 15A and 15B, when a load is applied at the time of installation, a force is applied in a direction to open the lower part of the joint surfaces 9, 9A and 9B, and on the other hand, on the inner surface side The top portion can be firmly joined by the resistance of the PC steel rod 12 thus formed. On the other hand, in the arched structure 15C, the inside angle θC of the top becomes small,
Since the top has a pointed shape, the loads P and Q shown in FIG.
Is applied, a negative bending moment is generated at the top 6, a tensile force is generated at the top of the top 6, and a force is generated in a direction to open the top of the joint surfaces 9 </ b> C, 9 </ b> C. 9C
Because it is arranged on the upper side, it is possible to effectively resist the tensile force.

The case where the dimension of the top portion 6 in the width direction is adjusted as described above will be described. As shown in FIG. 13, the molding form 51 of the arch-shaped unit plates 1, 1A, 1B, 1C is An outer surface molding portion 52 for molding the outer surface, an inner surface molding portion 53 for molding the inner surface, a side surface molding portion (not shown) for forming the side surface in the longitudinal direction of the structure, and a lower end surface molding portion for forming the lower end surface (FIG. (Not shown). Then, the joining surface molding portions 54, 54 for molding the respective joining surfaces 9, 9A, 9B, 9C.
A, 54B and 54C are selectively used, and preferably at the position of the duct 8, a sheath is formed to form the duct 8.
A plurality of arch-shaped unit plates 1, 1A, 1B, 1C are formed by placing the concrete 55 in the formwork 51, removing the mold, and removing the mold by adjusting the size of the top 6 to the width.

Further, in order to cope with a curved road or a slope road, it is necessary to form the side surface in the longitudinal direction of the structure obliquely. Although it was necessary to form a complicated side surface forming portion every time, the arched unit plate 1 of the present invention has a large number of flat surfaces 5N and 5G on the inner surface and the outer surface,
Since the N and the plane 5G form a continuous bent surface, a flat plate having a straight edge can be used for the side surface forming portion, and accordingly, an arch shape corresponding to a curved road or a slope road can be used. The form of the unit plate 1 is simplified.

As described above, according to the present embodiment, the tops 6 and 6 of the pair of arch-shaped unit plates 1 and 1 correspond to the first aspect .
The joining surfaces 9 are abutted and the tops 6, 6 are joined together to form an arched structure 15, and the arched unit plates 1, 1
In the method for manufacturing a precast concrete arch-shaped unit plate in which concrete is poured into a molding frame 51 for molding, a PC steel rod 12 as a joining member is inserted through the top 6 of the arched unit plate 1. the duct 8 provided with, said ducts
8 is opened at the joint surfaces 9, 9A, 9B, 9C,
The frame 51 includes a joint surface molding portion 54 for molding the joint surface 9.
The joining surface molding parts 54, 54A, 54B, 54
By changing C, the width of the top 6 in the width direction is adjusted according to the width of the arched structure 15, and the joining surfaces 9, 9A, 9
Since B and 9C form a plurality of parallel arched unit plates 1, by adjusting the dimensions of the top 6, the width of the arched structure 15 to which the arched unit plates 1 are joined can be adjusted. Are the joining surfaces 9, 9A, 9B,
Since only the mold plate for molding 9C needs to be changed, the arch unit plates 1, 1A, 1B, 1C forming the arch structures 15 having different widths can be molded by the common mold 51 .

As described above, according to the present embodiment, claim 2
When the arched structure 15 is substantially semicircular, the duct 8 is disposed below the joint surface 9 of the top portion 6. When the PC steel bar 12 resists, the arched unit plate 1 that can firmly join the joints can be manufactured.

Further, according to the third aspect of the present invention, the top portion 6 is provided with a thick portion 7 on the outer surface side, and the duct 8 linearly connects the joining surface 9 of the top portion 6 and the outer surface of the top portion 6. Therefore, even if the top portion 6 is shortened for dimensional adjustment, the duct 8 can be made relatively long due to the thick portion 7 on the outer surface of the top portion.
This is advantageous when setting 12 with tension.

FIG. 14 shows a second embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. Structure
An enclosing block 31 is erected on one side of the top of 15, and the mountain side of the enclosing block 31 is backfilled to form an inclined surface 32.

By backfilling one side of the arched structure 15 in this way, even if an unbalanced load is applied to the arched structure 15, the arched culvert 25 is an indeterminate structure with three rigid joints. A high strength can be obtained against a load, and the same operations and effects as those of the first embodiment can be obtained according to the first to third aspects.

FIGS. 15 to 18 show a third embodiment of the present invention. The same parts as those of the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. In the unit plates 1, 1A, 1B, 1C, the length of the top portion 6 in the width direction is different, but the shape of the step portion 10 is the same. Also, each of the arch-shaped unit plates 1, 1A, 1B, 1
The inner widths H, Ha, Hb, Hc of the arched structures 15, 15A, 15B, 15C formed of C are 12 meters, 11 meters, 10 meters, and 9 meters.

As described above, the length of the top 6 in the width direction was changed, and the thickness TS of the joint surface and the center position of the duct 8 were set as shown in Table 2 below. Note that, in this example, the thickness T at the bending position of the arch-shaped unit plates 1, 1A, 1B, 1C is set.
1, T2, T3, T4 are 400mm, 440mm, 4
80 mm and 520 mm.

[0036]

[Table 2]

Also in this example, the arched structure is formed at the joint surface.
In 15, 15A and 15B, the PC steel rod 12 is connected to the joint surfaces 9, 9A and 9B.
On the inner surface side of B, the arched structure 15C, the PC steel rod 12 was on the outer surface side of the joining surface 9C. Then, similarly to the arched structure 15, in the arched structures 15A and 15B, when a load is applied at the time of installation, a force is applied in a direction to open the lower part of the joint surfaces 9, 9A and 9B, and on the other hand, on the inner surface side The top portion can be firmly joined by the resistance of the PC steel rod 12 thus formed. On the other hand, in the arched structure 15C, since the inside angle θC of the top is small and the top is pointed, a negative bending moment is generated at the top when the loads P and Q shown in FIG. A tensile force is generated on the joint surface 9C, and a force in the direction of opening the upper part of the joint surface 9C is generated. However, since the PC steel bar 12 is disposed on the upper side of the joint surface 9C, the tensile force is effectively resisted. According to the first to fourth aspects, the same operations and effects as those of the above-described embodiment can be obtained.
Since A, 1B, and 1C have the same shape of the step portion 10, they can be more easily manufactured.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. For example, although the example in which the substructure is formed by cast-in-place concrete has been described, part or all of the substructure may be made of precast concrete. Also,
The PC steel in the bending direction may be tensioned by a pretension method. Further, in the embodiment, the arch-shaped unit plate whose plane is continuously bent is shown, but the inner surface of the arch-shaped unit plate may be formed in an arc.

[0039]

Effect of the Invention The process of claim 1, a pair of arched
With matching the bonding surface of the top portion of the unit plate, by joining the <br/> top cross to form an arcuate configuration, the arched
Casting concrete into the molding form of the unit plate and molding
In the method for producing a precast concrete arch-shaped unit plate, a duct for inserting a joining member is provided at the top of the arch-shaped unit plate , and the duct is
Opening at the joint surface, the molding form molds the joint surface
With a joint surface molding part
Wherein by adjusting the width dimension of the top to fit the width of the arcuate structure by changing the serial junction surface molding portion
Provided is a method of manufacturing an arch-shaped unit plate, in which a plurality of arch-shaped unit plates having parallel joining surfaces are molded, so that a molding frame can be shared and a product corresponding to a width can be easily manufactured. be able to.

According to a second aspect of the present invention, in the manufacturing method according to the second aspect of the present invention, when the arch-shaped structure is substantially semicircular, the duct is arranged below the joint surface of the top portion. It is possible to provide a method of manufacturing an arch-shaped unit plate which can be manufactured easily and can easily manufacture a product corresponding to a width.

Further, in the manufacturing method according to the third aspect, the thick portion is provided on the outer surface side at the top portion, and the duct communicates the joining surface of the top portion and the outer surface of the top portion linearly. In addition, it is possible to provide a method of manufacturing an arch-shaped unit plate in which a molding frame can be shared and a product corresponding to a width can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a front view of a hollow structure having an inner space width H showing a first embodiment of the present invention.

FIG. 2 is a plan view of the arched structure;

FIG. 3 is a cross-sectional view of the top of the arched structure.

FIG. 4 is a moment diagram of the same.

FIG. 5 is a cross-sectional view of the top of the arched unit plate.

FIG. 6 is a cross-sectional view of a lower portion of the arch-shaped unit plate.

FIG. 7 is a front view of the hollow structure whose inner space width is Ha.

FIG. 8 is a cross-sectional view of the top of the arched structure.

FIG. 9 is a front view of the hollow structure whose inner space width is Hb.

FIG. 10 is a cross-sectional view of the top of the arched structure.

FIG. 11 is a front view of the hollow structure whose inner space width is Hc.

FIG. 12 is a cross-sectional view of the top of the arched structure.

FIG. 13 is a cross-sectional view of a main part of a mold for forming the arched unit plate according to the third embodiment.

FIG. 14 is a sectional view of a hollow structure showing a second embodiment of the present invention.

FIG. 15 is a cross-sectional view of the top of an arch-shaped unit plate of a hollow structure having an inner space width of H showing a third embodiment of the present invention.

FIG. 16 is a cross-sectional view of the top of an arch-shaped unit plate of a hollow structure having an inner space width of Ha.

FIG. 17 is a cross-sectional view of the top of an arch-shaped unit plate of a hollow structure having an inner space width of Hb.

FIG. 18 is a cross-sectional view of the top of an arch-shaped unit plate of a hollow structure having an inner space width of Hc.

FIG. 19 is a moment diagram of an arched structure having a three hinge structure.

[Explanation of symbols]

1, 1A, 1B, 1C Arch-shaped unit plate 6 Top 7 Thick part 8 Duct 9, 9A, 9B, 9C Joining surface 12 PC steel rod 15, 15A, 15B, 15C Arch-shaped structure 51 Forming form 54, 54A , 54B, 54C Joint surface molding part

Continuation of the front page (56) References JP-A-6-136723 (JP, A) JP-A-5-171626 (JP, A) JP-A-5-138639 (JP, A) Nikkei Construction, Nikkei BP, Japan , February 9, 1996, 36-37 Abstract of the 48th Annual Meeting of the Japan Society of Agricultural Engineers Kanto Chapter, 92, 100 (58) Fields surveyed (Int. Cl. ⁷ , DB name) E21D 11 / 04 E01F 7/04

Claims (3)

(57) [Claims] 1. The joining of the tops of a pair of arched unit plates
With matching faces, by joining said top cross to form an arcuate configuration, mold frame of the arched unit plate
In a method for manufacturing a precast concrete arch-shaped unit plate in which concrete is poured into a mold and molded, a duct for inserting a joining member is provided at the top of the arch-shaped unit plate , and the duct is opened to the joint surface, and the duct is opened.
The mold form has a joint surface molding part for molding the joint surface.
For example, changing the joint surface molding portion with the common molding mold
By adjusting the width dimension of the top portion in accordance with the width of the arch-shaped structure, a plurality of joint surfaces are parallel.
A method for producing a precast concrete arched unit plate, comprising molding an arched unit plate. 2. The precast concrete arched unit plate according to claim 1, wherein the duct is disposed below the joint surface of the top when the arched structure is substantially semicircular. Manufacturing method. 3. The duct according to claim 2, wherein a thick portion is provided on the outer surface side of the top portion, and the duct communicates the joining surface of the top portion and the outer surface of the top portion linearly. Method of manufacturing precast concrete arched unit plate.