JP2010013859A - Covered conduit confluence structure and method of constructing covered conduit confluence - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a covered conduit confluence structure which contributes to improved workability and cost reduction in construction of a confluence of covered conduits formed of box culverts, and to provide a method of constructing the covered conduit confluence. <P>SOLUTION: In construction of the covered conduit confluence, the covered conduit 3 is converged to the linear covered conduits 1, 2 at right angles to form a T-shaped channel at which the confluence structure 10 is constructed. The confluence structure 10 is formed almost like a quadrangular cylinder, and cylindrical structures 4 forming the covered conduits 1, 2 are connected to front and rear openings formed therein along an axial direction. Further the confluence structure includes an opening formed in a side surface, to which the cylindrical structure 4 forming the covered conduit 3 is connected. The confluence structure is divided into front and rear cylinder sections 20, 30 at a location that divides the opening formed in the side surface. The cylindrical sections 20, 30 are formed of: bottom slab members 21, 31; right and left sidewall members 23, 22, 33, 32 erected from right and left side edges of the bottom slab members 21, 31; and top slab members 24, 34 arranged on the sidewall members, respectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a structure for confluence of a culvert that becomes a three-way (for example, T-shaped road) or a four-way (for example, a crossroad) part in a culvert formed by connecting precast concrete cylindrical structures such as box culverts. The present invention relates to a culvert junction construction method for constructing a body and a merging junction of the culvert.

For example, box culverts are used to construct various underdrains such as common ditches, public sewage, drainage canals, and human roads. The box culvert is a cylindrical structure, and a culvert is constructed by connecting the cylindrical structures.
Basically, each tubular structure has the same shape and is made of precast concrete. Therefore, the tubular structure as a box culvert is manufactured in advance by placing reinforcing bars in the formwork and placing concrete in a factory or other equipment, and transporting them to the construction site of a culvert with a truck or the like. Then, a culvert is constructed by connecting a plurality of cylindrical structures.

Here, when connecting box culverts of the same shape, a culvert that is a straight line is constructed. However, depending on the culvert, a single path may be branched into two from the middle, and others. Or a merging portion where three or more roads merge together is formed. That is, for example, a T-junction or a culvert that becomes a crossroads is provided.
Here, the part where three or more roads of the culvert join cannot be constructed with the above-mentioned box culverts of the same shape. Was.

However, when constructing the confluence of multiple underdrains with cast-in-place concrete, it takes time and labor to install a formwork for constructing a confluence of a relatively complex shape, and the work at the site becomes complicated. The work cost will increase.
Therefore, a proposal has been made in advance to reduce the cost in the field work and to facilitate the work by constructing the junction structure having a T-shape, a cross shape and a tubular structure with precast concrete. (For example, see Patent Document 1).

Japanese Patent Laid-Open No. 08-120746

  By the way, the box culverts can be manufactured with the same formwork because they have the same shape, and this reduces the cost. However, when the above-mentioned junction is made of precast concrete, a plurality of underdrains are used. As a result of merging, the shape becomes more complicated than the box culvert, and the formwork becomes complicated, which increases the cost of the formwork. Furthermore, there are not necessarily many culverts having a merging portion, and even a culvert having a merging portion often has one merging portion or several places. Therefore, only a small number of precast concrete joining parts are manufactured, and the high cost of the formwork is low and the manufacturing cost of the joining part is low.

In other words, the precast concrete junctions are costly, and the T-shaped or cross-shaped junctions are larger than other precast concretes, which may hinder transportation by truck. . In addition, there is a problem that it is difficult to carry in and install the underground part where the underdrain is formed. For example, since a large joining portion is heavy, a large heavy machine is required for lifting, which causes an increase in cost.
Therefore, it is not always cheaper than the joining part constructed by the cast-in-place concrete. Further, when considering not only the installation made of precast concrete but also the manufacture, transportation and installation, there is a problem that the work is not always greatly reduced.

  The present invention has been made in view of the above circumstances, and the culvert can be made of precast concrete, and the workability from manufacture to installation can be improved and the overall cost can be reduced. An object of the present invention is to provide a method for constructing a merging portion and a method for constructing a merging portion of a underdrain.

The junction structure structure of the underdrain according to claim 1 is formed in a substantially rectangular tube shape, the tubular structures constituting the underdrain are respectively connected to the front and rear openings along the axial direction, and A confluence structure structure of a culvert having an opening on at least one side surface thereof, to which a cylindrical structure constituting a culvert is connected to the opening,
At the position where the opening formed in the side surface is divided into front and rear, it has a configuration divided into front and rear cylinder parts,
Each cylindrical portion is composed of a bottom plate member, left and right side wall members erected on the left and right side edge portions of the bottom plate member, and a top plate member that is arranged on the side wall member.
These bottom plate members, left and right side wall members, and top plate members are each made of a separate and substantially plate-like precast concrete,
A cylindrical part is constructed by assembling these bottom plate members, left and right side wall members, top plate members,
In a state where the front and rear tube portions are connected, the interval between the side wall members that respectively constitute at least one side surface of these tube portions is an opening formed on the side surface. .

  In the first aspect of the present invention, the junction structure of the culvert is not provided integrally, but is divided into two divided portions, and each divided portion is a separate body and is substantially plate-shaped. Since the bottom plate member, the left and right side wall members, and the top plate member, which are precast concretes, are joined, the formwork does not have a complicated structure at the time of manufacturing, and the manufacturing cost can be reduced.

  In addition, even if the entire junction structure is larger than the box culvert used to construct ordinary underdrains, it can be used as a plate when transporting from the manufacturing site to the site, or when transporting it underground to the site. Since it can be handled, transportation and carry-in become easy. For example, since each member that becomes the junction structure is generally plate-shaped, it can be easily placed on the truck bed, and by placing it on top of each other, space efficiency in the bed improves, and depending on the weight of each member, It is also possible to carry many members.

In addition, each member is lighter than the entire merging section structure, so if it is lifted for each member and carried into the installation location, a large heavy machine that lifts the entire merging section structure is not required. The box culvert can be lifted sufficiently by heavy equipment that can be lifted.
In addition, by dividing the substantially rectangular cylindrical confluence structure front and rear at the opening portion on the side surface, it is not necessary to provide an opening portion on the side wall member constituting the side surface, and the side surface of the front cylindrical portion is configured. By setting it as the structure which has a space | interval between a side wall member and the side wall member which comprises the side surface of a rear cylinder part, the opening part to which the branched culvert is connected can be comprised.

Thereby, it becomes possible to make a side wall member into a simple structure without an opening part, and the manufacturing cost of a side wall member can be reduced.
Since the junction structure is composed of multiple members and needs to be assembled on site, the work on the site is more than installing an integral junction structure. Work on site is easier than building the entire structure, and forming, forming, transporting, carrying in, and the like are facilitated, improving workability as a whole.

The culvert merge section construction method according to claim 2 is a culvert merge section construction method using the culvert merge section structure according to claim 1,
In the installation space of the merging section of the culvert previously constructed underground, when constructing one of the front and rear cylinders in the merging section of the culvert, the bottom plate member of the cylinder section is installed,
Next, left and right side wall members are respectively installed on the left and right side edges of the bottom plate member,
Next, after installing the top plate member on the side wall member, it is joined using the PC steel material from the bottom plate member through the side wall member to the top plate member,
Similarly, after constructing the other cylinder part, these cylinder parts are joined using PC steel materials arranged across these cylinder parts,
A cylindrical structure that forms a culvert is connected to the opening at the front end of the front cylinder part, the opening at the rear end of the rear cylinder part, and the opening on the side surface of the front and rear joined cylinder parts. It is characterized by that.

  In invention of Claim 2, there can exist the same effect as the invention of Claim 1.

  According to the culvert junction structure and the culvert junction construction method of the present invention, the culvert junction can be constructed at a low cost by a relatively easy operation.

Hereinafter, a culvert junction structure 10 and a culvert junction construction method according to an embodiment of the present invention will be described with reference to FIGS.
The merging junction structure 10 of the culvert in this example is installed at a portion that becomes a T-junction of the culvert. For example, as shown in FIG. 17, another culvert is perpendicular to the straight culverts 1 and 2. 3 are joined.

Each undercarriage 1, 2 and 3 is constructed by connecting a rectangular precast concrete tubular structure 4 serving as a box culvert in a row.
In this example, the three culverts 1, 2 and 3 that join together have the same cross-sectional shape including the size, and the cylindrical structure 4 used is the same, Each culvert may have a different shape or size, or only one culvert may have a different size or shape from the other two culverts.

And the culverts 1 and 2 are arranged on the same axis, and if the culvert 3 does not join, it is a part constructed as a single culvert. The junction structure 10 is arranged between the two culverts 1 and 2 and may be interpreted as one culvert.
And the confluence | merging part structure 10 of the undercarriages 1,2,3 is formed in the substantially square cylinder shape as shown in FIGS. 13-17, and the undercarriages 1,12 in the axial direction are respectively in the undercarriages 11,12. 2 is connected, and has an opening 13 on at least one of the right and left side surfaces, and the cylindrical structure 4 forming the underdrain 3 is connected to the opening 13. It is for use.

And the confluence | merging part structure 10 has the structure divided | segmented into the front and rear cylinder parts 20 and 30 in the position which divides the opening part 13 formed in the said side surface into the front and back.
Further, the front and rear tube portions 20 and 30 are respectively composed of bottom plate members 21 and 31, left and right side wall members 22, 23, 32, and 33 erected on left and right side edges of the bottom plate members 21 and 31, It consists of top plate members 24 and 34 arranged on the side wall members 22, 23, 32 and 33.

The bottom plate members 21 and 31, the left and right side wall members 22, 23, 32, and 33, and the top plate members 24 and 34 are each made of a separate plate-like precast concrete.
The cylindrical portions 20 and 30 are constructed by assembling the bottom plate members 21 and 31, the left and right side wall members 22, 23, 32 and 33, and the top plate members 24 and 34.

  In a state where the front and rear tube portions 20 and 30 are connected, an opening formed between the side wall members 23 and 33 constituting at least one side surface of the tube portions 20 and 30 is formed on the side surface. 13 Therefore, the junction structure 10 is composed of a substantially plate-like member, and a member having an opening on the plate surface is not used.

  The bottom plate member 21 of the front cylinder part 20 is in a state in which left and right side edges on which the left and right side wall members 22 and 23 are placed protrude upward. Then, plate-like side wall members 22 and 23 are placed on the portion protruding upward to constitute the side surface of the cylindrical portion 20 that is continuous with the portion protruding above the left and right side edge portions of the bottom plate member 21. Yes.

That is, the corners 26 and 27 between the bottom plate and the side wall are formed on the bottom plate member 21 side, and the side wall members 22 and 23 are flat, whereas the bottom plate member 21 has the left and right side edges thereof. It is formed so as to protrude upward, and constitutes corners 26 and 27 between the bottom plate and the side wall. Further, the inner corner sides of the corner portions 26 and 27 are tapered surfaces. Moreover, in the corner | angular part 27 by which the opening part 13 is formed among the corner | angular parts 26 and 27, it will be in the state where the part used as the opening part 13 became one step lower than the part used as the outer side (front side) from it. Yes.
In addition, on the upper surfaces of the corner portions 26 and 27 of the bottom plate member 21, as shown in FIG. 2, a state in which the positioning pins 41 of the side wall members 22 and 23 project the tips upward on the portions on which the side wall members 22 and 23 are placed. It is buried in.

  Further, side wall members 22 and 23 disposed on the corner portions 26 and 27 of the bottom plate member 21 are fixed to the upper surface of the portion inside the corner portions 26 and 27 of the bottom plate member 21 with PC steel as will be described later. Until then, an insert 43 having a female screw hole that is screwed into a male screw portion on the lower end side of the pipe-like temporary support member 42 that supports the side wall members 22 and 23 is embedded.

  Further, as shown in FIG. 4, the upper surface of the bottom plate member 21 to which the side wall members 22 and 23 of the left and right corner portions 26 and 27 are joined is embedded in a state where a bolt 44 is fixed, and the coupler 45 is a bolt. In the state of being screwed to 44, it is exposed to holes opened in the upper surfaces of the corner portions 26 and 27, and the end of the PC steel material 50 can be joined to the coupler 45. A plurality of bolts 44 and couplers 45 are arranged in the left and right corner portions 26 and 27 so as to be spaced apart from each other in a line along the axial direction of the cylindrical portion 20.

  Further, as shown in FIG. 5, the bottom plate member 21 includes a sheath tube 47 for inserting a PC steel material in the corner portions 26 and 27 along the axial direction of the cylindrical portion 20 in the axial direction (front-rear direction). It is buried along. Further, a fixing portion 49 for fixing the front end portion of the PC steel material 48 inserted through the sheath tube 47 is provided in the central portion before and after the corner portions 26 and 27. In addition, a bearing plate is embedded and fixed to the fixing portion 49, and an end portion of the PC steel material in a state of passing through the supporting plate is fixed by a nut.

  Similarly, the bottom plate member 31 of the rear cylinder portion 30 is also provided with corner portions 36 and 37 having the same shape as that of the front cylinder portion 20. However, the rear cylinder part 30 and the front cylinder part 20 are reverse in the front-rear direction (the left-right direction is opposite) and have a mirror image relationship. Therefore, in the corner part 37, the part used as the opening part 13 is in the state which became one step lower than the back side. The bottom plate member 31 is also provided with positioning pins 41, inserts 43, bolts 44, a coupler 45, a sheath tube 47, and a fixing portion 49 as other configurations, similarly to the above-described bottom plate member 21.

  The side wall members 22 and 32 of the cylindrical portion 20 and the cylindrical portion 30 constitute the side wall on the side where the opening 13 is not provided, and the front and rear widths thereof are substantially equal to the bottom plate member 21 and the top plate member 24. . That is, the side wall members 22 and 32 have the same width as the axial width of the cylindrical portion 20. On the other hand, the front and rear widths of the side wall members 23 and 33 on the side where the opening 13 is formed are about half of the cylindrical portions 20 and 30, that is, the bottom plate members 21 and 31 and the top plate members 24 and 34. And this side wall member 23 (33) is arrange | positioned at the cylinder part 20 (cylinder part 30), ie, the front half side (rear half side) of the bottom plate member 21 (31) and the top plate member 24 (34), and is a cylinder. It arrange | positions so that the side surface used as the rear half (front half) of the part 20 (30) may be in the open state. This open part becomes the first half part (second half part) of the opening 13.

In addition, a plurality of sheath tubes 51 are embedded in the side wall members 22, 23, 32, and 33 along the vertical direction through which the PC steel material 50 is inserted.
Further, on the inner surface side of the side wall members 22, 23, 32, 33, a female screw that is screwed into a male screw portion on the upper end side of the pipe-like temporary support member 42 that supports the side wall members 22, 23, 32, 33 described above. An insert 52 having a hole is embedded. The upper end portion of the temporary support member 42 is screwed and connected to the insert 52 of the side wall members 22, 23, 32, and 33, and the lower end portion of the temporary support member 42 is screwed to the insert 43 of the bottom plate members 21 and 31. Connected. The temporary support member 42 whose upper end is fixed to the left side wall members 22 and 32 has a lower end connected to the insert 43 on the right side of the bottom plate members 21 and 31 and an upper end on the right side wall members 23 and 33. The fixed temporary support member 42 is connected at its lower end to the insert 43 on the left side of the bottom plate members 21 and 31.

Thereby, these temporary support members 42 and 42 are arranged obliquely intersecting in an oblique manner.
Further, the side wall members 22, 23, 32, and 33 have positioning holes in which the positioning pins 41 protruding from the upper surfaces of the corner portions 26, 27, 36, and 37 of the bottom plate members 21 and 31 are inserted in the lower end surfaces thereof. The hole member 54 is embedded with the hole opened on the lower surface.
Further, the side wall members 22, 23, 32, and 33 are provided with positioning pins 55 that are inserted into positioning hole members 63 provided in the top plate members 24 and 34 described later on the upper end surfaces thereof.

  The basic structure of the top plate member 24 is substantially the same as that of the bottom plate member 21, and the mirror image is in a relationship where the vertical direction is reversed (the horizontal direction is reversed). Therefore, the bottom plate member 31 of the rear cylinder portion 30 that is in a mirror image relationship with the bottom plate member 21 of the front cylinder portion 20 has the same shape as the top plate member 24 of the front cylinder portion 20, and has the same formwork. Manufacturable.

Similarly to the bottom plate member 21, corner portions 56 and 57 are provided on both side edges of the top plate member 24. Then, the corner portions 56 and 57 are placed on the side wall members 22 and 23. In addition, in the corner 57 on the opening 13 side, the portion on the opening 13 is one step higher than the portion on the side wall member 23. As a result, the upper side of the opening 13 is higher than the side wall members 22 and 23, and the lower side is lower than the side wall members 22 and 23, and the vertical length is longer than the side wall members 22 and 23.
In addition, the positioning hole member 63 described above is embedded in the lower surface of the corner portions 56 and 57 facing the side wall members 22 and 23 with the holes open to the lower surface.

However, as shown in FIG. 4, the top plate member 24 is not embedded with the above-described insert 43, and is opened to the upper surface side instead of the bolt 44 and the coupler 45 to which the lower end portion of the PC steel material 50 is connected. And the fixing | fixed part 62 which fixes the upper end part of PC steel material 50 is provided. Note that a hole is formed at the fixed portion 62 so that the PC steel material 50 can penetrate the top plate member 24.
Further, the top plate member 34 of the rear cylinder portion 30 is basically in a mirror image relationship in which the front-rear direction is reverse (the left-right direction is reverse) with respect to the top plate member 24 of the front cylinder portion 20. The other configurations are the same and have corner portions 58 and 59.

Therefore, the top plate member 34 of the rear cylinder part 30 has substantially the same shape as the bottom plate member 21 of the front cylinder part 20, and can be manufactured in the same formwork.
Similarly to the relationship between the top plate member 24 and the bottom plate member 31 described above, the top plate member 34 is not embedded with the above-described insert 43, and the bolt 44 to which the lower end portion of the PC steel material 50 is connected, and Instead of the coupler 45, a fixing portion 62 that opens to the upper surface side and fixes the upper end portion of the PC steel material 50 is provided. Further, a positioning hole member 63 is provided instead of the locating pin 41.
Further, as shown in FIG. 5, the top plate members 24 and 34 have sheath tubes 47 for inserting PC steel materials into the corner portions 56, 57, 58 and 59, respectively, similarly to the bottom plate members 21 and 31. It is embedded along the axial direction (front-rear direction). Further, a fixing portion 49 for fixing the front end portion of the PC steel material 48 inserted through the sheath tube 47 is provided in the central portion before and after the corner portions 26 and 27.

Each cylindrical part 20 and 30 which consists of each of the above members is made into the state which mounted the side wall member 22,23,32,33 on the right-and-left side edge part of the bottom plate members 21 and 31, and on these bottom plate members 21 and 31 The top plate members 24 and 34 are placed in a cylindrical shape.
Moreover, what joined these cylinder parts 20 and 30 in the state which faced along the axial direction becomes the junction structure 10.

A method for constructing a junction of culverts using such a merging junction structure 10 will be described.
Underground construction will be performed by excavation work. Here, under construction at a crossing portion of a culvert that becomes a T-junction, the culvert 1 and the culvert 2 are joined in a straight line, and the culvert 3 is perpendicular to the culverts 1 and 2 at the joint between the culvert 1 and the culvert 2. Are to be joined.
As shown in FIGS. 1 and 9, the underdrain 1 is constructed up to a portion excluding the cylindrical structure 4 joined to the junction structure 10. That is, it is in the state joined to the junction structure 10 by adding another cylindrical structure 4 to the culvert 1 connected with the cylindrical structure 4 already installed.

Note that a foundation 71 made of split stone and concrete or mortar is constructed below the underdrain 1.
And, with respect to the current underdrain 1, it is the installation position of the merge part structure 10 with an interval of one cylindrical structure 4, but the installation position of the merge part structure 10 is also A concrete base 72 is made of mortar.

The base portion 72 is one step lower than the base portion 71. That is, the installation position of the junction structure 10 is in a state in which a shallow hole is provided that is one step lower than the installation positions of the other culverts 1, 2, and 3. Note that the shallow hole, that is, the portion of the base portion 72 is longer than the axial length of the merging portion structure 10. This is because, as will be described later, to secure a space for the jack 81 used when joining the cylindrical portion 20 and the cylindrical portion 30 constituting the merging portion structure 10 with the PC steel material 48, and an end plate 73 described later is disposed. It is to do.
Further, the depth of the hole is slightly shallower than the height of the corner portions 26, 27, 36, 37 of the bottom plate members 21, 31.

  Then, the bottom slab member 21 of the cylinder part 20 is suspended from the ground side by a crane and installed in a portion adjacent to the foremost culvert 1 of the foundation part 72. At this time, an end plate 73 made of precast concrete is disposed at the boundary with the underdrain 1. In addition, since the bottom plate member 21 and the end plate 73 are arranged on the base portion 72, the height positions of these lower surfaces are the same. The end plate 73 is substantially the same height (slightly lower) as the corners 26 and 27 of the bottom plate member 21, and has substantially the same lateral width as the bottom plate member 21.

The end plate 73 has an opening portion because the junction structure 10 is longer than the tubular structure 4 of the underdrain 1 and the opening 11 is vertically longer than the tubular structure 4 of the underdrain 1. 11 is installed to prevent a part of the lower side from being exposed.
In addition, it arrange | positions in the state in which the edge part of the cylindrical structure 4 was mounted on the end plate 73. FIG.

  In addition, in the junction part structure 10, it joins in the state by which the edge part of the tubular structure 4 of the underdrain 3 of the same size as the tubular structure 4 of the underdrains 1 and 2 was inserted in the opening part 13 of the side surface. Therefore, the vertical length of the junction structure 10 is longer than the vertical length of the tubular structure 4, and the openings 11, 12 are longer than the culverts 1, 2. It has become. Therefore, it is necessary to close the upper end portion and the lower end portion of the openings 11 and 12 with the end plate 73.

  As shown in FIGS. 2 and 10, after the bottom plate member 21 is installed, the side wall members 22 and 23 are then suspended and placed on the corners 26 and 27 of the bottom plate member 21. At this time, as shown in FIG. 2, the alignment plate 41 protruding from the upper surfaces of the corner portions 26 and 27 is inserted into the alignment hole member 54 provided on the lower surfaces of the side wall members 22 and 23. The positions of the member 21 and the side wall members 22 and 23 are aligned. Accordingly, the positions of the sheath tube 51 of the side wall members 22 and 23 and the coupler 45 of the bottom plate member 21 are accurately aligned, and the PC steel material 50 passing through the sheath tube 51 can be coupled to the coupler 45.

  Further, when the side wall members 22 and 23 suspended from the bottom plate member 21 are installed, the temporary support member 42 is disposed between the side wall members 22 and 23 and the bottom plate member 21, and the lower end of the bottom plate member 21. The upper end of the insert 43 is screwed into the female screw, and the upper end is screwed into and joined to the female screw of the insert 52 of the side wall members 22 and 23. As a result, the oblique temporary support members 42 prevent the side wall members 22 and 23 from falling due to an earthquake or the like.

  Next, as shown in FIGS. 3 and 11, the top plate member 24 is installed on the side wall members 22 and 23. At this time, the positioning pins 55 projecting on the side wall members 22 and 23 are inserted into the holes of the positioning hole members 2 provided on the lower surfaces of the corners 56 and 57 of the top plate member 24 to insert the side wall members 22 and 23. The position of the top plate member 24 with respect to is adjusted. Thereby, the position of the fixing portion 62 of the top plate member 24 and the sheath tube 51 of the side wall members 22 and 23 are aligned.

  Next, as shown in FIG. 4, the bottom plate member 21, the side wall members 22 and 23, and the top plate member 24 are connected and fixed with a PC steel material 50. First, the PC steel material 50 is passed through the top plate member 24 from the opening of the fixing portion 62 of the top plate member 24 and the sheath tube 51 of each of the side wall members 22 and 23 is inserted, and the PC steel material is inserted. The lower end portion of 50 is screwed into the coupler 45 fixed to the bottom plate member 21. Note that male screws are formed on the upper and lower ends of the PC steel material 50, and female screws are formed on the coupler 45.

  Then, in a state where the lower end portion of the PC steel material 50 is fixed to the bottom plate member 21, a jack 82 (Devi dark jack) is connected to the upper end portion of the PC steel material 50 at the fixing portion of the top plate member 24, and the PC steel material is tensioned. A force is introduced, and then the upper end portion of the PC steel material 50 is fixed to the fixing portion 62. Thereby, the bottom plate member 21, the side wall member 22, and the top plate member 24 are connected by the PC steel material 50 on the left side of the cylindrical portion 20, and the bottom plate member 21, the side wall member 23, and the top plate member 24 are connected to the PC steel material on the right side of the cylindrical portion 20. 50 are connected.

  Next, as shown in FIGS. 5 and 12, the cylindrical portion 30 after the front and rear directions are reversed is assembled in the same manner as the front cylindrical portion 20. That is, the bottom plate member 31 is installed, the side wall members 32 and 33 are placed on the left and right on the bottom plate member 31, and the top plate member 34 is placed thereon. And these are connected by the PC steel material 50 similarly to the case of the cylinder part 20. When the bottom plate member 31 of the rear cylinder portion 30 is installed on the base portion 72, the PC steel material 48 for connecting the cylinder portion 20 and the cylinder portion 30 is previously placed in the sheath tube 47 of the bottom plate member 31. It is preferable to insert it. Since the PC steel material 48 has a length that is arranged from the central portion of the cylindrical portion 20 to the central portion of the cylindrical portion 30, the length is substantially the same as the longitudinal length of the bottom plate member 31. When inserted into the sheath tube 47 of the member 31, it does not extend greatly from the bottom plate member 31.

Here, since the bottom plate members 21 and 31 are arranged on the base portion 72 in the hole having a depth substantially the same as the vertical length of the bottom plate members 21 and 31, the bottom plate members 21 and 31 having two front and rear widths. If the PC steel material 48 is inserted into the bottom plate member 21 through the bottom plate member 31 from the rear end side of the bottom plate member 31, the PC steel material must be inserted from the outside of the hole. However, if it does so, PC steel 48 will become slanting and PC steel 48 cannot be inserted well.
Therefore, the PC steel material 48 is inserted into the rear bottom plate member 31 in advance, and after the bottom plate member 31 is installed, approximately half of the PC steel material 48 is moved from the rear bottom plate member 31 to the front bottom plate member 21 side. In addition, by this, even if it does not lengthen the hole used as the foundation part 72 very much, the connection by the PC steel material of the cylinder part 20 and the cylinder part 30 is attained.

  Next, after the bottom plate member 31, the side wall members 32 and 33, and the top plate member 34 of the rear cylinder portion 30 are connected, in the corner portions 26, 27, 36, and 37 of the two front and rear bottom plate members 21.31, The distal end portion of the PC steel material 48 inserted into the sheath tube 47 is fixed to the fixing portion 49 of the previous bottom plate member 21. Further, an extension steel material 46 is connected to the rear end portion of the PC steel material 48 via the coupler 45, and is connected to the PC steel material 48 via the extension steel material 46 from the rear end side of the bottom plate member 31 to the extension steel material 46. The tension is introduced by the jack 81 (center hole jack), and then the rear end portion of the PC steel material 48 is fixed to the fixing portion 49 of the rear cylinder portion 30. Thereby, it is set as the state which connected the cylinder part 20 and the lower part of the cylinder part 30. FIG.

The PC steel material 48 is inserted into the corner portions 56 and 57 of the front top plate member 24 and the corner portions 58 and 59 of the rear top plate member 34 in the same manner as the bottom plate members 21 and 31. Thus, the cylindrical portion 20 and the cylindrical portion 30 are connected to each other at the top plate member 24 and the top plate member 34.
Next, a grout material is injected into the sheath tubes 47 and 51. In this state, the junction structure 10 is almost completed as a single structure, but the underdrains 1, 2, and 3 need to be joined.

Next, as shown in FIG. 13, an end plate 73 is installed adjacent to the rear side of the cylindrical portion 30 in the same manner as the front side of the cylindrical portion 20. Next, as shown in FIG. 6 and FIG. 14, concrete is placed in a portion on the rear side of the cylindrical portion 30 of the hole of the base portion 72. The placed concrete portion 75 becomes a foundation part for the undercarriage 2 that is continuous with the foundation part 74 for the undercarriage 2.
Next, the tubular structure 4 that connects the undercarriage 1 and the tubular part 20 is suspended between the tubular part 20 and the undercarriage 1, and the tubular structure 4 is installed in the undercarriage 1 already. 4 and the cylindrical portion 20 are connected. In addition, joint members for fastening bolts are respectively embedded in end surfaces (joint surfaces) of the tubular portion 20 and the tubular structure 4 that are in contact with each other. By fastening these joint members with bolts, the tubular portion 20 and the cylindrical structure 4 adjacent to the cylindrical portion 20 of the underdrain 1 are connected.

In addition, the coupling member is in a state of being opened in the underdrain 1 and the merging portion structure 10, and can be fastened from the inside.
Next, as shown in FIGS. 15 and 6, the tubular structure 4 of the underdrain 2 is connected to the rear end side of the tubular portion 30. The connection is performed in the same manner as the case where the tubular structure 4 of the culvert 1 is connected to the front end side of the cylindrical portion 20.

Next, as shown in FIGS. 16 and 6, the end plate 73 is adjacent to the junction structure 10 on the cylindrical structures 4 and 4 adjacent to the junction structure 10 of the underdrain 1 and underdrain 2 respectively. Install in the part. These end plates 73 are also arranged to block the portions of the openings 11 and 12 that are longer in the vertical direction than the cylindrical structures 4 and 4 and exposed on the upper side of the cylindrical structures 4 and 4.
Next, as shown in FIGS. 7, 8, and 17, linear underdrains 1 and 2 are formed in the opening 13 formed by connecting the cylindrical portion 20 and the cylindrical portion 30 of the junction structure 10. The cylindrical structure 4 adjacent to the junction part structure 10 of the underdrain 3 joined at a right angle is joined.

  At this time, the distal end portion of the cylindrical structure 4 is inserted into the opening 13 by the thickness of the side wall members 23 and 33. In addition, the opening 13 is formed slightly wider than the outer shape of the cylindrical structure 4, and between the outer peripheral surface of the distal end portion of the cylindrical structure 4 and the inner peripheral surface of the opening 13, There is a gap, and a non-shrink mortar is placed in the gap, and the gap is closed, and the non-shrink mortar is used to prevent the gap from shrinking after curing.

Further, in this example, the joint structure 10 is in contact with the side surface where the opening 13 is provided, and at the position around the cylindrical structure 4 into which the tip end in the opening 13 is inserted. Concrete is placed.
That is, as shown in FIG. 7 and FIG. 8, on-site wound concrete 78 is provided around a portion adjacent to the joining portion structure 10 of the tubular structure 4 that becomes the underdrain 3.

Thereby, although the water-stopping and the intensity | strength improvement of the junction part of the junction part structure 10 and the underdrain 3 are aimed at, it is not necessarily required to provide the winding concrete 78.
Moreover, in the junction part structure 10, since the floor surface is lower than the culverts 1, 2, and 3, concrete is laid on the floor side in the junction part structure 10 as shown in FIG. The floor 79 may be formed so that the height of the floors of the underdrains 1, 2, and 3 and the height of the floor in the junction structure 10 are substantially equal.

  Basically, each bottom plate member 21. 31, side wall members 22, 23, 32, 33 and top plate members 24, 34 of the joining portion structure 10, and the joining between the tubular portion 20 and the tubular portion 30. In a joint portion between the joint portion 10 and the tubular structure 4 of the underdrains 1 and 2 excluding the underdrain 3, a water-stopping material such as rubber is disposed between the joining end surfaces of these members. It is like that.

  According to the culvert merging section structure 10 and the culvert merging section construction method as described above, the joints between the culverts are not on-site concrete, but by connecting substantially plate-shaped precast concrete members to each other. Since it is configured, it is possible to improve workability on the site and shorten the construction period.

  In addition, there is no cost for a complex-shaped formwork as in the case where the entire junction is made of a single precast concrete, and the cost for the formwork is reduced because a substantially plate-shaped precast concrete is manufactured. In addition, by forming the junction structure 10 in a state of being divided into two portions at the side opening portions, members having openings are not required, and each member is formed of a member having no opening, A part is comprised by each member. Therefore, it is not necessary to manufacture a complicated shape precast concrete having an opening, and the cost can be reduced.

  Further, the bottom plate members 21 and 31 and the top plate members 24 and 34 have a slightly complicated shape due to the corners, but the above-described bottom plate members 21 and 31 and the top plate members 24 and 34 that are not mirror images are the same. It becomes possible to manufacture with the same mold as the shape member. Further, by forming the opening only on one side surface, a mirror image-related member is generated. However, when the cross plate is used as described later, all the bottom plate members 21 and 31 and the top plate members 24 and 34 are the same. It becomes possible to manufacture with a mold, and further cost reduction can be achieved. Moreover, when it is set as a crossroad, the same member can be used also for the side wall members 22,23,32,33.

  In addition, in this example, although the junction part structure 10 used as a T-junction and the merging part construction method of a culvert were demonstrated, the side wall members 22 and 32 of the junction part structure 10 are used as the side wall member 23 of the side surface which has the opening part 13, 33, and in the bottom plate members 21, 31 and the top plate members 24, 34, the corner portions 26, 36, 56, 58 are stepped like the corner portions 27, 37, 57, 59. In the case where the opening 13 is formed on the side surface opposite to the side where the opening 13 is provided, the cylindrical structure 4 constituting the fourth underdrain is formed in the opening 13. It is good also as what forms a crossroad as what joins similarly to.

Although the cross-sectional shapes of the underdrains 1, 2, and 3 are the same, for example, the underdrains 1, 2, and 3 may include other underdrains that differ in width and height. In this case, the junction structure 10 is basically configured in accordance with the largest culvert, and when a gap or the like is generated at a joint portion with the small culvert, for example, the same as the end plate 73 or the like. The gap may be closed with a precast concrete plate.

It is a side view which shows the confluence | merging part structure in the middle of the construction for demonstrating the confluence | merging part construction method of the underdrain which concerns on embodiment of this invention. It is a front view which shows the confluence | merging part structure in the middle of construction for demonstrating the confluence | merging part construction method of the said culvert. It is a front view which shows the confluence | merging part structure in the said construction middle. It is a front view which shows the confluence | merging part structure in the said construction middle. It is a side view which shows the confluence | merging part structure in the middle of the said construction. It is a side view which shows the junction part structure in the middle of the said construction. It is a side view which shows the said junction part structure. It is a front view which shows the cylinder part of the said confluence | merging part structure. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the confluence | merging part structure in the said construction middle. It is a perspective view which shows the said junction part structure.

Explanation of symbols

1, 2, 3 Underdrain 4 Tubular structure 10 Junction structure 11, 12, 13 Opening 20, 30 Tubing 21, 31 Bottom plate member 22, 23, 32, 33 Side wall member 24, 34 Top plate member

Claims (2)

A cylindrical structure that is formed in a substantially rectangular tube shape, is connected to front and rear openings along the axial direction, and has an opening on at least one of the left and right side surfaces, and A merging section structure of a culvert connected to a cylindrical structure that forms a culvert in an opening,
At the position where the opening formed in the side surface is divided into front and rear, it has a configuration divided into front and rear cylinder parts,
Each cylindrical portion is composed of a bottom plate member, left and right side wall members erected on the left and right side edge portions of the bottom plate member, and a top plate member that is arranged on the side wall member.
These bottom plate members, left and right side wall members, and top plate members are each made of a separate and substantially plate-like precast concrete,
A cylindrical part is constructed by assembling these bottom plate members, left and right side wall members, top plate members,
In a state where the front and rear tube portions are connected, the interval between the side wall members that respectively constitute at least one side surface of these tube portions is an opening formed on the side surface. Underground confluence structure. A method for constructing a junction of underdrains using the junction section structure of underdrains according to claim 1,
In the installation space of the merging section of the culvert previously constructed underground, when constructing one of the front and rear cylinders in the merging section of the culvert, the bottom plate member of the cylinder section is installed,
Next, left and right side wall members are respectively installed on the left and right side edges of the bottom plate member,
Next, after installing the top plate member on the side wall member, it is joined using the PC steel material from the bottom plate member through the side wall member to the top plate member,
Similarly, after constructing the other cylinder part, these cylinder parts are joined using PC steel materials arranged across these cylinder parts,
A cylindrical structure that forms a culvert is connected to the opening at the front end of the front cylinder part, the opening at the rear end of the rear cylinder part, and the opening on the side surface of the front and rear joined cylinder parts. A method for constructing a junction of culverts characterized by the above.

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