JPH0230509Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention is related to the excavation of a trench that is intended for backfilling, and is used in the field of preventing wall collapse of the trench until the trench is backfilled. used in That is, the present invention relates to an earth retaining device that can be easily installed in the trench and removed from the trench.

[Prior art and its problems]

By the way, when it is intended to bury electrical conduits for carrying telephone lines or power lines, gas pipes, supply pipes, drainage pipes, etc. underground, it is customary to employ the so-called cut-and-cover backfill method. Therefore, in the burial work, a trench of a required depth is first excavated using an excavating machine such as a backhoe, and the above-mentioned underground objects are laid at the bottom of the trench, and then the trench is backfilled.

In the excavation and earthwork of trenches that require backfilling, in order to ensure the smooth progress of laying underground objects at the bottom of the trench and to ensure the safety of the work, only the period until backfilling is carried out. Temporary earth retaining is often required on the wall of the trench.

For this reason, in the past, as shown in Figures 1 and 2, for example, a large number of vertical sheet piles B were first laid out along both the left and right walls of the groove A, and then a horizontal upright beam C was installed inside each of the sheet piles. Align the left and right belly-up beams C,
Alternatively, as shown in Figures 3 and 4, vertical stakes E are driven at regular intervals along both the left and right walls of groove A, and the distance between each pile is A retaining structure is widely used in which a large number of horizontal partition plates F are lined up vertically on the outside, and horizontal struts G are stretched between the left and right piles E, E.

However, with such conventional earth retaining structures, construction at the time of installation and dismantling at the time of removal are all done on-site, making installation and removal time-consuming and time-consuming, and the process from the start of excavating the trench to the completion of backfilling. This unnecessarily prolongs the work period, and also causes the inconvenience of propagating tremendous noise and vibration around the site when driving the sheet piles B or piles E.

[Technical issues of invention]

Therefore, the technical problem of the present invention under the above-mentioned current situation is that it is easy to install and remove from excavated trenches with the premise of backfilling, and that it can be constructed and dismantled each time. The aim is to provide an unnecessary pre-assembled retaining device.

[Technical means of invention]

The technical means of the present invention that addresses such technical problems basically consists of 1.
A base frame 1, a total of two plates 2 attached from the outside to the left and right sides of the frame, and two plates 2 on the left and right to the front and back of the frame. It consists of a total of two or more jacks 3, at least one of which is arranged in such a way that they are stretched.

The frame 1 described above consists only of a hexahedral three-dimensional skeleton structure formed by welding together multiple beams in the vertical, longitudinal, and horizontal directions, and therefore has a large structure. Has mechanical strength. In addition, each of the left and right plates 2 corresponds to a wall plate that shields the left and right sides of the frame 1, and is similarly endowed with great mechanical strength, and has a high mechanical strength with respect to the frame 1. It is said to be movable within a finite range only in the direction away from the side. Further, each of the front and rear jacks 3 has a structure in which the overall length is variable, and is appropriately connected to the left and right plates 2 at both ends.

[Effect of invention]

The earth retaining device according to the present invention, which was realized by the above-mentioned technical means, is completely assembled in advance, and except for the time of assembly and repair after long-term use, it cannot be installed at the place of use or applied. Even when removed from a location, there is no need for construction and dismantling each time.

Such a retaining device is installed as schematically shown in FIGS. 6 and 7. First, with the left and right plates 2, 2 in contact with both sides of the frame 1 to reduce the width of the entire device as much as possible, the entire device is excavated using an appropriate crane or the like. Lower it to the bottom of groove A. Therefore, this groove A needs to be excavated to a width slightly larger than the minimum width W ₁ that can be reduced of the entire device. Next, the left and right plates 2, 2 are pulled to the left and right using the front and rear jacks 3, and moved to the positions shown by the chain lines in Figures 6 and 7, increasing the width of the entire device from W ₁ to W ₂ . Let it open.

This expanded state is maintained by the above-mentioned jacks 3, but it is a feature of the present invention to further increase the number of jacks or use multiple bolts in combination to maintain the expanded state even more firmly. This is a desirable development.

The earth retaining device installed in the trench A in this manner achieves sufficient earth retention for both the left and right wall surfaces of the trench with the left and right plates 2, thereby preventing the walls from collapsing. In this state of use, the earth pressure applied to each plate 2 can normally be sufficiently supported by the above-mentioned jacks 3 or bolts used together, but even if unexpectedly excessive earth pressure Even if the jack 3, etc. is destroyed under an abnormal situation where pressure is applied, the plate 2 pushed back by the earth pressure will be sufficiently supported by the frame 1, and the minimum width of the entire device will be maintained.
Keep W ₁ .

Note that it is actually very difficult to excavate trench A with completely the same width in the length direction and depth direction, so it is difficult to excavate trench A with completely the same width in the length direction and depth direction. It's unavoidable.

Therefore, there is a narrow part in groove A,
If there is no room to expand the width of the entire earth retaining device to _W2 , push open only the front or rear of both the left and right plates 2, 2, as shown by solid lines or chain lines in Fig. 8, or As shown by solid lines or chain lines in FIG. 9, only the top or bottom may be pushed open.

On the other hand, the above-mentioned earth retaining device installed in trench A is
It is removed as follows. First, both the left and right plates 2, 2, which had expanded the width of the entire device to W ₂ , were
By pulling it back to the original position shown by solid lines in Figures 6 and 7 and bringing it into contact with both sides of the frame 1, the width of the entire device is reduced to W ₁ , and then the entire device is moved to an appropriate position. Pull it up from inside trench A using a crane, etc. Since this pulling-up is performed after reducing the width of the entire device, it is hardly affected by earth pressure. Therefore, it is possible to easily remove the earth retaining device from within trench A, and Backfilling can begin immediately.

[Effect of idea]

Therefore, according to the technical means of the present invention as described above, when excavating a trench with the assumption that it will be backfilled, temporary earth retention can be applied to the wall of the trench only for a period until the trench is backfilled. It is possible to provide a suitable earth retaining device, and in addition, compared to conventional earth retaining devices, it eliminates the need for construction and disassembly each time it is installed in a trench and removed from the trench, thereby saving the time and effort required for this. Therefore, the earth retaining device can be installed and removed easily and quickly, and the total work period from the start of trench excavation to the completion of backfilling can be significantly shortened, and other effects can be expected.

In addition, according to this technical means, the installation and removal of the entire earth retaining device can be carried out quickly as described above, so compared to the conventional method that required a long time to construct and dismantle on-site, the collapse of the trench wall during that time can be avoided. It is possible to improve the safety of installation and removal work by avoiding the situation where the installation and removal work is carried out, and since there is no need to drive sheet piles or piles, the noise and vibration associated with this can be completely eliminated, resulting in a quiet and quiet installation. It can also be expected to have effects such as enabling earth retaining construction.

Furthermore, according to this technical means, it is possible to standardize the dimensions of earth retaining construction, and it is also possible to use the earth retaining device repeatedly under normal usage conditions, making it easy to achieve a significant reduction in earth retaining costs. In addition, workers who are engaged in work such as laying underground objects can reliably maintain the earth retention even under abnormal usage conditions where excessive and unexpected earth pressure is applied. It can also be expected to have effects such as being able to better ensure the safety of people.

〔Example〕

Next, a specific embodiment of the present invention will be described with reference to FIG. 5 and FIG. 10 and subsequent drawings.

First, the frame 1, which has a hexahedral three-dimensional skeleton structure, has a total of four vertical longitudinal beams 11 arranged on the front, rear, left and right sides, and a total of four vertical longitudinal beams 11 arranged on the front, rear, left and right sides, as most clearly shown in Fig. 5. A total of four horizontal horizontal beams 1 in the front-rear direction arranged between the upper ends and the lower ends of the longitudinal beams 11 and 11.
2, and a plurality of horizontal struts 13 (three in the illustrated example) arranged between the left and right vertical beams 11, 11 in the front and rear. These beams 11, 12, and 13 are fixedly integrated with each other in advance by welding or the like to form the frame 1 having high mechanical strength. In addition, in several places on the top surface of this frame 1,
As illustrated in FIGS. 10, 11, and 15, a lifting fitting 14 is provided for use when lifting with a crane or the like.

Each of the two left and right plates 2 has a square or rectangular shape surrounded by the left and right sides of the frame 1, that is, the front and rear two vertical beams 11, 11 and the upper and lower two horizontal beams 12, 12. It functions as a wall plate for shielding the side part. Therefore, in order to provide each of these plate bodies 2 with a large mechanical strength sufficient to withstand the earth pressure applied during use, as shown in FIG. 5 and FIG. A total of two vertical groove beams 21, 21 with a U-shaped cross section are arranged so that one side is open toward the other, and a horizontal upper beam 22 and a lower beam 23 are respectively arranged between the upper and lower ends of both groove beams. Similarly, a plurality of horizontal intermediate beams 24 are distributed at appropriate intervals between both groove beams, and the area surrounded by these groove beams 21, 21 and the upper and lower beams 22, 23 is shielded. It consists of a steel plate 25 such as a keystone plate which has a high bending strength, and is fixed and integrated with each other by welding or the like.

Each of these plates 2 is attached to the left and right sides of the frame 1 from the outside so that it can only move in the direction away from the frame, and is semi-permanently assembled with the frame 1. . For such a combination movable only in the above direction, groove beams 21 arranged at both front and rear ends of the plate body 2 are used in the illustrated example, and the groove beams are connected to the frame body 1.
The front and rear longitudinal beams 11, 11 are individually slidably engaged with each other. Therefore, the frame 1 of the plate 2
When moving in the direction away from the plate, there is no risk of shifting the position of the plate in the front-rear direction.

Furthermore, each jack 3 is arranged at the front and rear of the frame body 1.
is horizontally spanned between the front and rear ends of both plate bodies 2, 2 located on the left and right sides of the frame, and has a structure in which the overall length can be changed at any time, and at both ends. , are connected to jack receivers 26, 26 provided on the inner side of each side end of both plate bodies 2, respectively.

Therefore, in the earth retaining device configured as described above, by minimizing the total length of the jack 3, the left and right plates 2 are brought into contact with the sides of the frame 1, and the overall length of the device is reduced. The horizontal width can be minimized, and by operating the jack 3 to increase the overall length, each plate body 2 can be stretched in the direction away from the frame body 1, and the horizontal width can be gradually increased.

However, when the left and right frames 2 are stretched to increase the width of the entire device, the jacks 3
If the tension force is insufficient with just one stand at a time,
As shown by the chain line in Fig. 5, a similar jack 3'
One or more units may be added in the front and rear, and these may be arranged vertically in parallel.

On the other hand, it is easiest to use a turnbuckle as a screw jack for the jack 3, as illustrated in FIGS. The tips of the male threaded shafts 32, 33, which have opposite threads, are connected to the aforementioned jack holders 26, 26 of the left and right plates 2, respectively.

However, since the turnbuckle described above is operated manually, it takes a certain amount of effort and time to extend and contract the entire length. Therefore, instead of this, a fluid pressure cylinder unit as a fluid pressure jack is adopted, and this unit is connected to the jack receivers 26, 26 of each of the left and right plates 2 at the rear end of the cylinder and the tip of the plunger, respectively. By doing so, the entire length can be expanded and contracted more easily and quickly, although a separate fluid pressure source is required.

By the way, when installed in an excavated trench, a large earth pressure is applied to each of the left and right plates 2, which are stretched with jacks 3 to increase the width of the entire device. This earth pressure can be supported by the above-mentioned jack 3, and by adding the jack 3', it can be supported even more reliably.
There is a certain amount of anxiety in being able to support and bear such great earth pressure over a long period of time.

Therefore, in this embodiment, as illustrated in FIGS. 11 and 14, bolt receiving plates are installed at approximately equal intervals at several locations above and below the inner side of both front and rear ends of each plate body 2, including the jacking receivers 26. 27 are provided, and nuts 15 are provided in an internal state at positions facing the receiving plate 27 on each of the longitudinal beams 11 on the front, rear, left, and right sides of the frame 1, respectively. Therefore, each bolt 28 inserted into each bolt receiving plate 27 from the inside
into the nuts 15 facing each other,
By pushing the plate 2 in the direction away from the frame 1 via the receiving plate 27, the earth pressure applied to the plate 2 can be more strongly supported and received over a long period of time.

Note that the movable range of the plate 2 in the direction away from the frame 1 is limited because the entire earth retaining device is always kept in an assembled state and there is a limit to the extendable length of the jack 3. However, the range of movement required for installation and removal is actually not very large.

Therefore, in this embodiment, the depth dimension from the open end of the groove beams 21 provided at both ends of the plate body 2 is set to several times the thickness of the vertical beam 11 in the frame body 1, and the above-mentioned jack holder 26 and bolt A receiving plate 27 is arranged at the opening edge of the groove beam 21. Therefore, the movable range of the plate body 2 is relatively limited to the range in which the longitudinal beam 11 can move from side to side within the groove beam 21;
No matter how the groove beam 21 is moved within the above range, the groove beam 21 is always kept engaged with the longitudinal beam 11.
This is convenient because the movement of the plate 2 relative to the frame 1 can be made smooth.

In addition, in this embodiment, a plurality of guide plates 29 are provided that protrude inwardly from the opening edge of the groove beam 21 and come into sliding contact with each strut 13 of the frame body 1.
Therefore, when the plate body 2 moves within the above movable range, the guide plate 29 prevents vertical displacement of the plate body.
When the frame 1 is lifted by a crane or the like, the state in which the plate 2 is assembled to the frame can be well maintained.

Further, in this embodiment, a ladder 4 is attached to the inner surface of either the left or right plate 2, taking care not to impair the movability of the plate relative to the frame 1. Therefore, when the earth retaining device is installed in an excavated trench, there is no need to prepare a separate ladder, making it easy for workers to enter and exit the trench.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an example of a conventional earth retention for an excavated trench, Fig. 2 is a sectional view taken from the - line in Fig. 1, and Fig. 3 is a plan view showing another example.
Figure 4 is a sectional view taken from the - line in Figure 2;
The figure is an exploded perspective view schematically showing the technical means of the present invention.
FIG. 6 is a plan view schematically showing the usage state of the device according to the present invention, FIG. 7 is a front view taken from the - line in FIG. 6, and FIG. 8 is a plan view schematically showing another usage state. FIG. 9 is a front view schematically showing another usage state, FIG. 10 is a partially cutaway plan view showing a specific embodiment of the present invention, FIG. 11 is a partially cutaway front view, 12 is a cross-sectional view of a portion of FIG. 11 taken along the - line, FIG. 13 is a cross-sectional view of a portion of the same view taken from the − line, FIG. 14 is a cross-sectional view of a portion of the same view taken from the − line, and FIG. Figure 10 -
It is a sectional view of a part seen from a line. 1...Frame body, 11...Vertical beam, 12...Horizontal beam, 1
3... Stray beam, 14... Hanging fitting, 15... Nut, 2... Plate, 21... Groove beam, 22... Upper beam, 23... Lower beam, 24... Intermediate beam, 25...
Steel plate, 26... Jacket bracket, 27... Bolt receiving plate, 28... Bolt, 29... Guide plate, 3, 3'...
...Jyatsuki, 4...Ladder.

Claims (1)

[Claims for Utility Model Registration] (1) One frame with a hexahedral three-dimensional skeleton structure, and a finite range that extends only in the direction away from the frame to the left and right sides of the frame. It consists of two left and right plates that are movable along the outside, and at least one jack with a variable overall length that is placed in front and back of the frame so as to stretch between the two left and right plates. An earth retaining device for excavation and earthwork, characterized in that: (2) The skeletal structure of the frame consists of a total of four vertical longitudinal beams placed on each side of the front, rear, left and right, and a total of four vertical beams placed between the top and bottom ends of the front and rear vertical beams on each left and right side. It consists of horizontal horizontal beams in the front and rear direction, and horizontal cross beams that are horizontal in the left and right directions and are arranged between the left and right vertical beams in each front and rear, and that each of these beams is fixed and integrated with each other in advance. An earth retaining device for excavation and earthwork according to claim 1 of the utility model registration claim characterized by: (3) Utility model registration claim 1, which is characterized in that two or more jacks for tensioning between two plate bodies are arranged at the front and rear of the frame body.
Earth retaining device for excavated earthworks as described in . (4) The earth retaining device for excavated earthworks according to claim 1 or 3 of the utility model registration claim, characterized in that a turnbuckle is employed as a jack for tensioning between two plate bodies. (5) The earth retaining device for excavation and earthwork according to claim 1 or 3, characterized in that a hydraulic cylinder unit is adopted as a jack for tensioning between two plate bodies. .