JP2837676B2 - Underground line for distribution line - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a line for burying cables such as a distribution line for power supply, a transmission line, and a communication circuit in the ground. More specifically, the present invention relates to an underground line for embedding cables such as distribution lines in the ground, particularly in a shallow layer.
In this specification, the distribution line means not only a distribution line for supplying power but also a cable including a transmission line, a communication circuit, and other cables such as an optical fiber cable.

(Prior Art) In recent years, in particular in urban areas, there is an increasing demand for underground distribution lines in which distribution lines are laid in tubular or block-shaped lines buried underground in place of overhead distribution lines.

As a conventional underground conversion method for distribution lines, as shown in FIG. 4 (A), a pipeline 101 such as a steel pipe, a concrete pipe, or a plastic pipe is buried deep underground and a distribution line 102 is drawn in.
Or, a common method is to bury a common groove for cables and collectively underground all overhead lines other than power distribution lines such as telephone circuits. In any case, it is assumed that the burial is buried at a place considerably deeper than the road surface 103, for example, at a depth of about 1.2 m when the vehicle is under a roadway, because it is separated from the influence of the vehicle and the like. Note that reference numeral 104 indicates the underground.

As shown in FIG. 4 (B), as an exceptional method of embedding road construction methods and technical standards for electrical equipment,
2 is a cable hole 2 in a flat reinforced concrete block
Prepare a prefabricated underground pipeline forming material 203 with drilled 01,
An underground pipeline laying method has been proposed in which the underground pipeline is formed by joining and burying this so that it is substantially flush with the ground surface 205 such as a sidewalk 204 or a roadway (Japanese Patent Application Laid-Open No. Sho 61) −18310
issue). Note that reference numeral 206 in the figure is a distribution line.

(Problems to be Solved by the Invention) However, as shown in FIG. 4 (A), in the case of arranging deep underground, the amount of excavation and backfilling civil works is increased, and furthermore, the construction of safety-retaining earth retaining walls is performed thereon. And so on. In addition, when laying in an already-developed area, it is difficult to construct because it is often laid on sidewalks where gas pipes and other buried objects are buried in addition to heavy traffic. For this reason, construction costs are much higher than overhead distribution lines, for example, about 10 times in urban areas, requiring a long construction period. In addition, when an accident such as a short circuit in the distribution line occurs,
Since the excavation has to be performed again, a large amount of time and cost is required for the duplication work, and the service to the customers is deteriorated.

In addition, low-voltage lines become unnecessary gradually as the distribution lines become higher in line with urban development. However, the removal work is not easy, and large construction costs are incurred.

In the case of a common ditch, it is easy to carry out restoration work, etc., but it also requires complicated procedures for management because it also accommodates lines other than distribution lines, resulting in a significant reduction in customer service. Requires measures to protect other cables from accidents. In addition, a single company must bear enormous costs to make a dedicated groove, which is not practical.

4 (B) is effective for reducing the civil engineering cost and facilitating the confirmation of the track, but the overload is applied to the joint between the prefabricated underground pipeline forming materials 203. In addition, since the ground reaction force is concentrated, it is difficult to use it in a place where the ground is weak, or there is a problem that the settlement of the ground must be dealt with by increasing the size and strength of the block. In addition, cable holes 201 that cannot be opened and closed
Since the distribution line 206 is drawn in and buried in the ground, if a short circuit accident or the like occurs, the entire block 203 must be digged up and restoration work must be performed, and the Contains.

The present invention reduces the cost of undergrounding distribution lines, enables quick and easy restoration accidents at the time of accidents, and enables easy removal and collection of distribution lines that will become unnecessary in the future. It is intended to provide a neutralization line.

(Means for Solving the Problems) In order to achieve this object, the underground railway line for distribution lines of the present invention is provided with a partition wall lower than the side wall and has two or more grooves for accommodating one set of distribution lines. A block which is provided in parallel and forms a recessed space above the partition wall to allow another member to be fitted therein, and a bottom provided with a projection for fitting with the recessed portion of another block; and a block fitted to the recessed portion of the block. A lid having a projection at the bottom, and connecting the blocks in the groove axis direction, fitting the projection at the bottom with the recess at the top, stacking two or more layers vertically and partitioning the upper block side wall. The lid is supported by a wall, and the lid, the upper block and the lower block are arranged in a staggered manner in the axial direction and are buried in a shallow layer immediately below the pavement road surface.

Further, in the underground distribution line according to the present invention, the side wall and the partition wall of the block are slopes such that a groove formed therebetween becomes narrower toward the bottom. .

Further, in the underground distribution line according to the present invention, unevenness is formed on an end surface of the block in the axial direction so as to be fitted to a mating side in an axial direction and a direction orthogonal thereto.

(Operation) Accordingly, the upper wheel load or the like acting from above is supported by the side wall and the partition wall of the block with a short span, and a sufficient load bearing function is exhibited. Further, the upper load, the ground reaction force, and the ground load are dispersed by the upper block, the lower block, and the lid arranged in a staggered manner, and do not concentrate on the joint. Further, the lid, the block, and the blocks have a structure in which they are joined only by fitting the concave and convex portions of each other.

(Examples) Hereinafter, the configuration of the present invention will be described in detail based on examples shown in the drawings.

1 (A) and 1 (B) show an embodiment of a line structure for underground distribution lines of the present invention. This underground line structure for distribution lines has a structure in which blocks 1, 1 'having two or more grooves 11 for accommodating one set of distribution lines and a cover 2 for closing the blocks 1 are several times closer to a pavement surface 7 of a sidewalk or a roadway. It is buried just below cm.

The blocks 1, 1 'are provided with a partition wall 13 lower than the side wall 12, and two or more grooves 11 for accommodating a set of distribution lines 8 are formed in the groove axial direction (longitudinal direction) in parallel. This groove 11 is preferably narrower toward the bottom, i.e.
The slope 12 and the partition wall 13 are formed so that the width of the groove 11 formed therebetween decreases toward the bottom. This increases the pressure resistance to horizontal earth pressure. Further, since the smaller the groove portion 11 is, the smaller the whole block can be made and the construction scale can be reduced, it is sufficient to secure at least a sufficient space for accommodating one set of distribution lines.
On the other hand, it is necessary to take a balance between the maximum value of the internal pressure rise at the time of cable short-circuit and the block strength, and it is preferable to appropriately select a minimum width based on these balances. At this time, the high-voltage distribution line 8 'is accommodated in the lower block 1',
If the low-voltage distribution line 8 is accommodated in the upper block 1 side, the upper block 1 functions as a shield, so that the explosion pressure at the time of the short circuit accident of the high-voltage distribution line 8 'can be confined.
The public can be effectively protected by preventing the road surface from blowing away.

The upper portion of the block 1 is open, and a concave space 14 surrounded by the side wall 12 is formed above the partition wall 13. The recessed space 14 allows other members such as the lid 2 or the other block 1 to be fitted therein, and simultaneously supports the other members to be fitted into the space 14 on both side walls 12 and the partition wall 13 of the block, and has a groove shaft for these members. Block movement in the horizontal direction perpendicular to the direction.
As a result, since the lid 2 is correctly positioned with respect to the upper block 1 and the upper block 1 is correctly positioned with respect to the lower block 1 ', the support of the lid 2 or the block 1 is performed symmetrically and evenly. Prevents wind from leaking toward the road surface.

Further, a projection 15 is provided at the bottom of each of the blocks 1 and 1 'so as to fit into the recessed space 14 of another block. This protrusion
The height of 15 is the same as the height difference between the block side wall 12 and the partition wall 13, that is, the height of the concave space 14, and the width is equal to or smaller than the distance between the inner wall surfaces of the block side walls 12. In the case of this embodiment,
The protrusion 15 has a rectangular shape, but may have a trapezoidal shape corresponding to the slope of the side wall and the partition wall 13.

In addition, unevennesses 16 and 17 are formed on the axial end surfaces of the blocks 1 and 1 'so as to be fitted to each other in the axial direction and the direction orthogonal to the other blocks 1 and 1'. These irregularities 16,17
As shown in FIG. 2, one end face has a convex portion 1 of another block.
When the concave portion 16 into which the 7 'is inserted is formed, a convex portion 17 which is inserted into the concave portion 16' of another block is formed on the other end surface. The side walls 12 of the blocks 1 and 1 'are provided with knockout portions (thin portions that can be broken by hitting) 18 for drawing in the two distribution lines 8. Reference numeral 23 denotes a wrecker embedding nut for convenience of transportation.

The lid 2 is provided in a plate shape having a thickness enough to withstand the overload. At the bottom of the lid 2, a projection 21 that fits into the recessed space 14 of the block 1 and a seating surface 22 that contacts the side wall 12 are formed.
22 is provided so as to be simultaneously supported by the side wall 12 and the partition wall 13 of the block.

The blocks 1, 1 'constructed as described above are
It is formed by the concrete which was given. For example, it is made of prestressed concrete to make it easy to transport and handle, for example, about 1 m long.
1 'is provided with two grooves 11 of about 130 × 130 mm.
In this case, the reinforcing bars 24 in the blocks 1 and 1 'are cut, so that the flow of the stray current can be hindered and corrosion can be prevented. Left and right seats 19 of the projection 15 at the bottom of this block and the projection of the lid
The left and right seating surfaces 22 have a working margin of 2 mm or more, preferably 2 to 5 mm, and are provided wider than the thickness of the corresponding side wall 12. As a result, a lid or the like having a considerable weight can be easily overlapped by two workers without displacement. In addition, the lid 2 and the blocks 1, 1 'are not limited to reinforced concrete, and may be made of other materials, for example, plastics decoded and reinforced by, for example, polyvinyl chloride plastic, glass fiber, carbon fiber, metal fiber, or the like. It is also possible to reduce the weight.

(Embodiment 1) For example, in a structure as shown in FIGS. 1 (A) and 1 (B), when two 6.6V cables and two 100V: 200V class cables are laid 5 cm below a sidewalk (asphalt) 7, wheel load of T20 as a design load (wheel load after total load 20t), taking into account the impact pressure of the static soil pressure (asphalt pavement 2.0 t / m ²⁾ and at the cable fault (6.6KV3 phase short circuit), manufactured by reinforced concrete The specifications of the lid 2 and the blocks 1, 1 'in this case are as follows.

When the block width is 380 mm, the minimum block side wall thickness is 40 mm,
The minimum partition wall thickness is 40 mm, the dimensions of the groove 11 are 130 × 130 mm, the block height is 230 mm, and the maximum lid thickness is 90 mm. In addition, a reinforcing bar having a diameter of 10 mm is used.

Here, the internal pressure of the impact was 3 kg / cm ² for 0.4 seconds at the time of the accident, but did not cause harmful damage to other healthy cables and road structures.

Using the blocks 1 and 1 'and the lid 2 configured as described above, underground distribution lines are performed as shown in FIGS. 1 (A) and 1 (B).

As shown in FIG. 1 (A), the distribution line
1 'is buried immediately below a pavement road surface, covered with a cover 2, sanded and backfilled soil 6 is thinned, and asphalt pavement 7 is formed.

That is, after digging the groove 5 by taking an extra dug space of about 200 mm left and right in the width of the blocks 1 and 1 ′, the rubble stone 4 and the mortar 3 are laid on the ground 9, and the lower block 1 is laid thereon.
Place 1 '. Block 1 ′ is composed of axial end surface irregularities 16,
17 are combined in a straight line in the axial direction. In each groove 13, one set or one line of cables, for example, high-voltage distribution lines 8 'are laid. Next, the upper block 1 is placed on the lower block 1 'so as to be staggered in the groove axis direction. This disperses the load on the ground and the ground reaction force and prevents concentration on these block connecting portions, thereby preventing land subsidence. When the upper block 1 is fitted to the lower block 1 ', the projection 15 at the bottom of the upper block 1 is inserted into the concave space 14 of the lower block 1'.
This is performed by fitting. Since the upper block 1 and the lower block 1 'are overlapped by the fitting of the projections 15 and the recesses 14, the distribution block 8' in the lower block 1 'is freely exposed by removing the upper block 1. I can make it. After the upper block 1 is installed, the low-voltage distribution line 8 is laid in each groove 11. Then, after the cover 2 is placed on the upper layer block 1, sand or soil 6 of about 5 cm is covered, and paved with asphalt 7 or the like. The block is preferably 2
The cable accommodation capacity can be increased by stacking more layers than necessary, but depending on the case, even one layer can be constructed. In this case, by arranging the lid 2 and the blocks 1 in a staggered manner, the load on the ground and the reaction force of the ground are dispersed, and the ground does not sink.

(Effects of the Invention) As is clear from the above description, the underground distribution line according to the present invention has one distribution line with a partition wall lower than the side wall.
Since two or more grooves for storing each set are provided and two or more blocks which can be vertically fitted are arranged in a staggered manner, and the lid and the upper layer block are supported by the side wall and the partition wall with a short span. Despite having the same cable capacity, it can be made compact, road usage fees can be reduced, and it can withstand land subsidence and mechanical strength even when buried in shallow places, and shallow places directly under paved road surfaces Can be filled in.

Therefore, since the burial depth (crown) is almost only the asphalt part (about 5 cm), only a small excavation work to dig a groove 30 to 50 cm deep from the road surface is sufficient, and no earth retaining wall construction is required Further, since backfilling work is extremely reduced, the construction cost and the construction period can be greatly reduced.
For example, simply comparing the excavated area ratio results in about 1/6.

Moreover, in the event of an accident, the track can be opened simply by cutting the asphalt surface and removing the lid, and the restoration work can be performed extremely quickly and easily. On the other hand, although it is shallow, it is buried under the paved road surface, which can prevent tampering by outsiders, and in the event of a cable accident such as an explosion due to a short circuit accident on the high voltage distribution line, the upper block, Lid, backfill soil, asphalt, etc. are shielded, so public safety can be maintained.

In addition, since it is buried immediately below the pavement road surface, the amount of backfill soil is extremely small, and there is no road collapse after construction.

In addition, since the cable can be taken out only by cutting the asphalt, the distribution lines can be easily increased or decreased, or the cable can be replaced in response to increase or decrease in power demand or unnecessary or aging.

In addition, since it is buried in the shallow part of the road, there is no possibility that other buried objects already buried, such as gas pipes and communication lines, will be disturbed.

In addition, since it is housed in a groove for one set and one line,
High reliability with no construction errors. In addition, since it is possible to reduce the cost, it is not necessary to form a common groove, and the safety in management is improved.

[Brief description of the drawings]

1 (A) and 1 (B) show an embodiment of a line structure for underground distribution lines according to the present invention, wherein (A) is a side view and (B) is a II line of (A). It is an expanded sectional view. FIG. 2 (A),
(B) and (C) show an embodiment of the block of the present invention, wherein (A) is a perspective view, (B) is a front view, and (C) is a side view of a longitudinal joint. FIG. 3 is a front view showing another embodiment of the block. FIGS. 4A and 4B are explanatory views showing an example of a conventional underground line for distribution lines. 1, 1 '... block, 2 ... lid, 7 ... paved road surface, 8 ...
... distribution line, 9 ... ground, 11 ... groove, 12 ... side wall, 13 ...
Partition wall, 14: recessed space, 15: projection, 16, 17 ... unevenness.

Continuation of the front page (56) References Japanese Utility Model Showa 60-162155 (JP, U) Japanese Utility Model Showa 61-54049 (JP, U) Japanese Utility Model Showa 55-43340 (JP, U) Japanese Utility Model Showa 62-111728 (JP, U.S.A.) , U) Actually open sho 59-145225 (JP, U) Actually open sho 59-145226 (JP, U) Actually open sho 60-22585 (JP, U) Real public sho 60-31373 (JP, Y2) Real public hei 3-29959 (JP, Y2) (58) Field surveyed (Int. Cl. ⁶ , DB name) H02G 9/00-9/12

Claims (3)

(57) [Claims] 1. A partition wall lower than a side wall is provided, two or more grooves for accommodating a set of distribution lines are provided in parallel, and a concave space is formed above the partition wall to allow other members to be fitted therein. A block provided with a projection at the bottom that fits into the recess of the other block, and a lid having a projection at the bottom that fits into the recess of the block, connecting the block in the groove axis direction; The bottom protrusion and the upper recess space are fitted to each other, and two or more layers are vertically overlapped, and the lid is supported by the side wall and the partition wall of the upper layer block. The lid, the upper layer block, and the lower layer block are staggered in the groove axis direction. An underground railway line for distribution lines, which is arranged in a shape and is buried in a shallow layer portion immediately below a pavement road surface. 2. The underground power distribution system according to claim 1, wherein the side wall and the partition wall of the block are slopes such that a groove formed therebetween becomes narrower toward the bottom. Track. 3. An arrangement according to claim 1, wherein said block has an axial end face formed with concavities and convexities on an end face in the axial direction, which are fitted to each other in an axial direction and a direction orthogonal thereto. Underground line for electric wire.