JPH0244962B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for constructing a prefabricated manhole constructed by stacking a plurality of concrete blocks such as frame blocks, straight wall blocks, and slant wall blocks. It is.

[Prior Art] This type of manhole is constructed by, for example, placing a chestnut foundation or the like at the bottom of excavated ground, laying a bottom slab block on this foundation, and placing a column block or a straight wall block on top of the bottom slab block. It is generally constructed by stacking a plurality of concrete blocks, such as sloping wall blocks, and then backfilled with soil around the blocks for use.

However, recent backfilling work is carried out using heavy equipment such as bulldozers, so that uneven earth pressure tends to act on the stacked blocks during the work. Therefore,
If the blocks are not firmly joined together, there is a problem in that the blocks may become misaligned during backfilling.

In order to solve this problem, we can wrap a strip around the joints of vertically adjacent blocks,
Alternatively, a method has been proposed in which a connecting plate is attached to the outer periphery of the upper block to the lower block to directly connect each block to prevent misalignment between the blocks. However, when the upper and lower blocks are joined by such a method, misalignment is likely to occur between the two blocks when they are stacked up. As a result, problems arise in that both blocks are joined while their relative positions remain misaligned, and that it becomes difficult to attach the connecting plate, etc., and that it takes time and effort to correct the positions of the blocks.

[Problems to be Solved by the Invention] As described above, the present invention solves the problem caused by the misalignment of the blocks that occurs when the blocks are stacked together, that is, the problem that occurs when the blocks are stacked together in the completed manhole. This is intended to solve the problem that the efficiency of the construction work is adversely affected due to residual positional deviations in the circumferential direction or the need to correct the positional deviations of the blocks before tightening the joint.
In other words, the present invention aims to provide a construction method that can easily and reliably position and stack blocks, and can efficiently construct a manhole.

[Means for Solving the Problems] In order to achieve the above-mentioned objects, the present invention constructs a manhole by stacking a plurality of concrete blocks such as frame blocks, straight wall blocks, and inclined wall blocks. In this case, one of the joint surfaces of the blocks that are to be adjacent to each other above and below with the joint surfaces butted against each other has a shaft portion and a guiding taper portion having a diameter larger than the shaft portion and tapered at least on the tip side thereof. A fastener comprising a head is erected in such a way that it cannot be pulled out with a gap left between the head and the joint surface, and an end wall with a hole is attached to the joint surface on the other hand. A box, which is exposed at the bottom, is opened on the circumferential surface of the block, and by butting the two blocks together, the head of the fastening tool is inserted into the box through the hole, using the guiding action of the tapered part. A washer having a notch through which the shaft of the fastener can be inserted is inserted between the head of the fastener and the end wall of the box from a direction perpendicular to the axis of the fastener. It is characterized in that the two blocks are attached to each other, thereby connecting the two blocks to each other.

[Function] According to such a means, when stacking blocks, the fixing tool provided upright on one joint surface of the blocks serves as a positioning pin, and the blocks are prevented from shifting. . Moreover,
A tapered part is provided at the tip of the head of the fastening tool, and the guiding action of this tapered part is used to insert the head into the box through the hole. There is no problem such as time consuming engagement between the fastener and the box when stacking the boxes.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 5.

The manhole 1 shown in FIG. 1 is constructed by sequentially stacking a plurality of concrete blocks, namely, a bottom block 2, a frame block 3, a straight wall block 4, and an inclined wall block 5. Specifically, the bottom block 2 is a disc-shaped one laid on a chestnut foundation 6 with a mortar layer 7 interposed therebetween, and has an annular joint surface 2a at the outer peripheral edge of its upper surface. At the same time, a protrusion 2b for positioning is provided in an annular shape on the outer peripheral edge of the joint surface 2a. The frame block 3 is a cylindrical body whose lower end is fitted inside the protrusion 2b of the bottom block 2 and whose joint surface 3a on the lower end side is joined to the joint surface 2a of the bottom block 2. A pipe 8 constituting a sewerage system is connected to the required portions of the surrounding wall.
An invert 11 having an inverted arch-shaped groove 9 continuous with the tube 8 is installed at the bottom of the rod block 3. Further, the straight wall block 4 is a cylindrical body placed on the body block 3 with the joint surface 4a on the lower end side abutted against the joint surface 3b on the upper end side of the body block 3. be. Further, the slanted wall block 5 is placed on the straight wall block 4 with the joint surface 5a on the lower end side abutting against the joint surface 4b on the upper end side of the straight wall block 4. It is formed into an eccentric cylindrical body having a substantially truncated conical shape. A receiving frame 13 for holding the lid 12 in an openable and closable manner is placed on the joint surface 5b on the upper end side of the slanted wall block 5 via a concrete adjustment ring 14 and a plurality of adjustment rubbers 15, and the receiving frame bolts. It is fixed using 16.

When constructing a manhole by stacking a plurality of blocks 2, 3, 4, and 5 in this way, the following construction method is adopted. That is, on one of the blocks 4 and 5 which are to be adjacent to each other above and below with their joint surfaces facing each other, for example, the straight wall block 4, cap nuts 17 which open at the joint surface 4b are spaced equiangularly apart in the circumferential direction. At the same time, a bolt 18 serving as a fastener is screwed into each of these cap nuts 17 so as to be unable to be pulled out, leaving a gap 20 (FIG. 2). The bolt 18 has a cylindrical head 18c having a tapered part 18a at the tip and a hexagonal column wrench hook 18b in the middle, and a thread with a smaller diameter than the head 18c carved on the outer periphery. A shaft portion 18d is provided. In addition, iron boxes 19 are buried in three locations corresponding to the respective cap nuts 17 of the other block, that is, the inclined wall block 5. The box 19 is a housing-shaped box that opens on the inner circumferential surface of the inclined wall block 5, and has an end wall 1.
The outer surface of the block 9a is exposed on the joint surface 5a of the block 5. This end wall 19a has an oval-shaped hole 1 through which the head 18b of the bolt 18 can pass.
9b is drilled (Fig. 2). An anchor 21 for firmly embedding the box 19 in the straight wall block 4 is fixed to the outer surface of the other end wall 19c of the box 19 by welding or the like. Then, when placing the inclined wall block 5 on the straight wall block 4 with the joining surfaces 5a and 4b abutting against each other, the head 18b of each bolt 18 is guided by the tapered portion 18a. and protrude into the corresponding box 19 through each hole 19b (FIG. 3). After that, a washer 2 is inserted into the gap 20 existing between the head 18b of each bolt 18 and the inner surface of the end wall 19a of the box 19.
Enter 2. (Figure 4). The washer 22 has a wedge-shaped cross section with a circular outer periphery, and has a long hole-shaped notch 22a opening at the outer periphery. That is, this washer 22 has a tapered shape in which the opening end side of the notch 22a is thinner. The opening width w of this notch 22a is set to an intermediate dimension between the diameter of the shaft 18d and the diameter of the head 18c of the bolt 18, and the shaft 18d is inserted into the notch 22a. I'm trying to make it possible. Therefore, by driving the washer 22 in a direction perpendicular to the axis of the bolt 18 with the notch 22a corresponding to the gap 20 portion of the shaft 18d, the washer 22 is inserted into the bolt 18. The straight wall block 4 and the inclined wall block 5 can be firmly joined by being wedged between the head 18c of the box 19 and the inner surface of the end wall 19a of the box 19. In this embodiment, the same construction method as described above is adopted when stacking the straight wall block 4 and the frame block 3, and when stacking the frame block 3 and the bottom plate block 2. are doing.

In addition, 23 indicates each box 1 after the wedge fixation.
9 is filled with mortar. Also, 24 is
The seal groove 25 provided in an annular manner on the upwardly facing joint surfaces 2a, 3b, 4b is connected to the downwardly facing joint surfaces 3a, 4a, 4b.
This is a protrusion provided in an annular manner on 5a. This protrusion 25 is adapted to fit into the seal groove 24 when the blocks 2, 3, 4, and 5 are joined together. The seal groove 24 and the protrusion 25 are omitted only in the portion where the cap nut 17 and the box 19 are provided. Also, 26
is a foothold for inspection.

However, according to the construction method described above,
When stacking blocks 2, 3, 4, and 5, the bolt 18 screwed into the nut 17 engages with the hole 19b of the corresponding box 19 and functions as a positioning pin. ,3
and 4, and positional deviations between 4 and 5 are reliably prevented. Furthermore, the bolt 18 is provided with a tapered portion at its tip, and the bolt 18 is inserted into the hole 19b of the box 19 by utilizing the guiding action of the tapered portion 18a. The bolt 18 and the box 19 when stacking blocks
This makes it easier to engage with the

Then, by simply driving the washer 22 into the gap 20 and wedging it, adjacent blocks can be firmly joined together.

Therefore, after stacking the blocks, there is no need to correct misalignment of the blocks, attach strips and connecting plates to the required locations, and screw bolts into designated nuts. , it is possible to construct manholes efficiently and reliably. Furthermore, there is no need for the operation of rotating and tightening bolts for connection, and from this point as well, the effect that each block can be connected quickly and easily can be obtained. The manhole 1 constructed in this way consists of blocks 2 and 3, blocks 3 and 4,
Since blocks 4 and 5 are firmly connected to each other by bolts 18, there will be no possibility of displacement between blocks 2, 3, 4, and 5 due to uneven pressure generated during backfilling work. Of course.

Note that the present invention is not limited to the above embodiments, and the following modifications are possible.

First, the fastening device provided on one block is not limited to a bolt, but for example, as shown in FIGS. 6 and 7, a pin with large diameter heads 27b and 28b provided at the tips of shaft portions 27a and 28a. 27, 28, etc. may be used. The pin 27 is fixed by embedding the proximal end of the shaft portion 27a within the block 4. Further, the pin 28 is
A hole 29 is drilled in the block 4, and the shaft portion 28a is inserted into the hole 29 and fixed with an adhesive such as epoxy resin 30, so that the block 4 is vertically attached so that it cannot be pulled out. And these pins 2
Tapered portions 27c and 28c for guiding are also provided at the tips of the heads 27b and 28b of 7 and 28, respectively.

In addition, when using bolts as fasteners,
Instead of a wedge-shaped washer, a flat washer 122 may be used as shown in FIGS. 8 to 11. That is, in this case, a nut 17 that opens to the joint surface 4b is provided on one 4 of the blocks 4 and 5 which are to be adjacent above and below with the joint surfaces 4b and 5a abutted against each other, and a tightening bolt is attached to the nut 17. 18 is screwed in with a margin left, and a hole 19 is inserted in the other side.
A box 19 with an end wall 19a attached with b exposed on the joint surface 5a is provided with an opening on the inner peripheral surface of the block 5, and the head 18c of the bolt 18 is inserted by abutting both the blocks 4 and 5. protrudes into the box 19 through the hole 19b, and connects the head 18c of the bolt 18 and the end wall 19 of the box 19.
A flat washer 122 having a notch 122a through which the shaft 18d of the bolt 18 can be inserted is inserted from a direction perpendicular to the axis of the bolt 18,
Thereafter, the bolts 18 are tightened to connect the blocks 4 and 5.

Furthermore, it goes without saying that the shape of the head of the fastener including the tapered part is not limited to that of the above embodiment.
For example, it may be as shown in FIGS. 12 and 13. That is, the fastener 1 shown in FIG.
The entire head 118c of No. 18 is tapered by the tapered portion 11.
8a. Further, the head 218c of the fastening tool 218 shown in FIG. 13 consists of a large diameter portion 218e that locks the washer, and a tapered portion 218a having a smaller diameter than the large diameter portion 218e. Further, the shape of the taper part itself is not necessarily limited to a conical shape, and for example, the shape of the taper part itself is not limited to a conical shape, and for example, a tapered part 318a shown in FIG. It may also be a truncated conical shape with no edges.

Further, in the above embodiment, a case was explained in which a fixing device is provided in the lower block of the upper and lower adjacent blocks, and a box is provided in the upper block, but conversely, a box is provided in the lower block. In addition, the present invention also includes a device in which a fastening device is provided on the upper block.

Furthermore, the number of locations connected by the fasteners and boxes is not limited to three, but may be two or four or more.

Furthermore, the box is not limited to being made of iron, and the method of fixing it to the block is not limited to burying an anchor. The hole formed in the end wall is not limited to an oval shape and may be circular, but if the hole is oval, engagement with a fastener such as a bolt becomes easier.

Further, the shape of the washer is not limited to the above-mentioned shape, and various modifications such as a rectangular outer shape are possible.

[Effects of the Invention] As described above in detail, according to the present invention, when stacking blocks, the fastening tool protruding from one block engages with the hole of the corresponding box and functions as a positioning pin. Therefore, problems caused by misalignment of blocks that occur when blocks are stacked together, such as circumferential misalignment between blocks remaining in the completed manhole, or It is possible to reliably solve the problem that the efficiency of construction work is adversely affected due to the need for work to correct the positional deviation of the blocks, and the problem that it takes time and effort to connect each block. Moreover, since the head of the fastener is provided with a tapered portion for guiding, the fastener can be easily inserted into the hole of the block. Therefore, the work of stacking blocks can be carried out smoothly, and the manhole can be constructed efficiently.

[Brief explanation of the drawing]

Figures 1 to 5 show an embodiment of the present invention, Figure 1 is a sectional view, Figures 2 to 4 are process explanatory diagrams of block joint tightening work, and Figure 5 is an exploded view showing the main parts. FIG. FIGS. 6 and 7 are partial sectional views showing other embodiments of the fastener according to the present invention. FIGS. 8 to 11 are process explanatory diagrams showing still other embodiments of the present invention. FIGS. 12 to 15 are schematic explanatory diagrams showing other embodiments of the tapered portion according to the present invention. 1... Manhole, 2... Bottom block, 2a
...joint surface, 3...body block, 3a, 3b...
...joint surface, 4...straight wall block, 4a, 4b...
Joint surface, 5... Slanted wall block, 5a... Joint surface,
6... Chestnut stone foundation, 7... Mortar layer, 8...
Pipe, 9... Groove, 11... Invert, 12... Lid, 13... Receiving frame, 14... Adjustment ring, 15...
... Adjustment rubber, 16 ... Receiving frame bolt, 17 ... Nut (cap nut), 18 ... Fastening tool (bolt), 18
a...Tapered part, 18b...Wrench hook, 18c
...Head, 18d...Shaft, 19...Box,
19a... End wall, 19b... Hole, 19c... End wall, 20... Gap, 21... Anchor, 22...
Washer, 22a... Notch, 23... Mortar, 2
4... Seal groove, 25... Projection, 26... Footrest,
27, 28... Fastening tool (pin), 27a, 28a
...Shaft, 27b, 28b...Head, 27c, 2
8c...Tapered part, 29...Hole, 30...Epoxy resin, 31...Washer, 118...Fixing tool, 11
8a...Tapered portion, 118c...Head, 122...
...Washer, 122a...Notch, 218...Fixing tool, 218a...Tapered part, 218e...Large diameter part, 318a...Tapered part, 418a...Tapered part.

Claims (1)

[Claims] 1. When constructing a manhole by stacking multiple concrete blocks such as wall blocks, straight wall blocks, slanted wall blocks, etc., the joint surfaces of the blocks should be butted against each other, and the joint surface of one of the blocks that should be adjacent above and below, A fastener comprising a shaft portion and a head portion having a diameter larger than the shaft portion and having a tapered guiding taper portion at least on the distal end side, leaving a gap between the head portion and the joint surface. At the same time, a box with an end wall with a hole exposed on the joint surface is opened on the circumferential surface of the block, and both blocks are The head of the fastener is projected into the box through the hole using the guiding action of the tapered part, and the fastener is secured between the head of the fastener and the end wall of the box. Construction of a manhole characterized in that a washer having a notch through which the shaft of the fixture can be inserted is attached from a direction perpendicular to the axis of the fastening fixture, thereby connecting both blocks. Method.