JPS6028977B2 - Construction method and device for underground structures - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The invention of this application uses a tunnel of a structure in the ground, such as a water-stop wall formed in the ground, when constructing a low-temperature liquefied gas tank as an underground tank. This invention relates to a construction method and a construction device directly used in the construction method, and in particular, to backfilling of the trailing shaft with sand from a leading shaft to a trailing shaft excavator mixed with a coagulating material in the process of digging a shaft. This invention relates to a method for constructing an underground structure in which the structure is built intrinsically in the ground, and a rhombus thin film directly used therein.

(Prior Art) As is well known, there are various construction methods for constructing structures in the ground, but as structures have recently become larger, various new problems have arisen.

For example, in storage tanks for low-temperature liquefied gas such as LMG, underground tanks are sometimes constructed as a countermeasure against pollution, scenery, and scenery, but underground water flows between the impermeable layer deep underground and between the tank bottom plate and side slope. Frost heave occurs due to the inevitable drop in temperature, which poses a problem in design and construction.

<Problems to be Solved by the Invention> Therefore, in order to solve this problem, by constructing a water-stop wall up to the impermeable layer on the side of the tank, the gap between the water-stop wall, the impermeable layer, and the tank bottom plate is improved. It is sufficient to dehydrate the groundwater, but it is not practical to construct a cutoff wall that reaches the impermeable layer that exists in the depths of more than 100 layers underground using the current continuous underground wall construction method due to the large scale of the construction work. This is close to possible, and as a result, in reality, only about 30 tanks can be built underground, which means that the tank capacity is also restricted due to the water-stop wall.

However, as mentioned above, there is a need for larger tanks to increase storage capacity, etc., so increasing the size of the tank makes the design conditions difficult.
It has become desirable to construct an impermeable layer with a depth exceeding zero skin.

Therefore, in the above-mentioned conventional technology, there are various technical difficulties in dealing with the problem simply by scaling up.
Of course, the techniques for dealing with underground structures are not limited to the above-mentioned cut-off walls, but as long as they are constructed from the ground surface, they can reach ultra-deep depths, and when constructing large-sized walls, excavation precision is required. However, it is inevitable that there will be problems with excavation equipment, construction methods, excavated soil, etc.

The purpose of this invention is to solve the problems of construction of underground structures based on the above-mentioned prior art as a technical problem to be solved. It is an object of the present invention to provide an excellent method and apparatus for constructing an underground structure that can be stacked to form a water-stopping wall, etc., and that is useful in the field of underground excavation technology application in the construction industry.

Means and operation for solving the above-mentioned problems In accordance with the above-mentioned object, the structure of the present invention, which is summarized in the above-mentioned claims, always achieves the above-mentioned problems by utilizing the known tunnel construction method. A work point is placed near the face, and a horizontal tunnel is excavated into the ground. Between the leading shaft and the trailing shaft, the excavated soil is mixed with a coagulating material such as cement from the leading shaft to the trailing shaft. The basic method is to build structures using the ground tunnel walls as a type of formwork by backfilling them, and furthermore, using this construction process, various underground structures can be stacked vertically. This technology takes technical measures to allow the formation of

<Example> Next, an example of the invention of this application will be described below with reference to the drawings.

The embodiment shown in Figures 1a and 1b is an embodiment showing the basic embodiment of the invention of this application, in which a predetermined excavator 3 is used to dig into the ground 2 of the ground 1 from the ground surface G by the existing tunnel construction method. Lead shaft 4 will be excavated.

In principle, the trailing portion can be immediately backfilled with the excavated soil generated in the leading tunnel 4, but this remains the so-called "earthworm ecology" and does not form a structure. Therefore,
The excavator 3 is made up of an excavator 5 at the tip, a transport mechanism section 6 at the center, and a backfilling section 7 at the rear filling section. Process earth and sand to make it suitable for structural materials.

Of course, it is also possible to supply concrete from outside in conjunction with the removal of earth and sand.

After the leading tunnel 4 has completed a predetermined length while removing the excavated earth and sand from the rear part and partially forming the structure,
The same excavator 3 is operated to excavate and form the following tunnel 8 in the next stage as close to and parallel to the leading tunnel 4 from the level indicated by ○ in the same manner as described above. Then, the excavated earth and sand of the following tunnel 8 is mixed with cement as aggregate in the filling section 7 by the conveyor of the conveyance mechanism section 6, and is turned into soil concrete etc. as shown in FIG. It is filled as a filler while backfilling, forming part 9 of the underground structure, and the process is continued.

During this time, the excavator's sand is thoroughly mixed with cement and make-up water (or using nearby groundwater, etc.) to compress it, and its cross section is made as shown in Figure lb.

Incidentally, the expression of the ground mass 1 in the right half of the figure shows an embodiment in which it is formed as a retaining wall of a structure, and the dotted line portion 1' is an excavated portion.

The embodiment shown in FIG. 2 explains an embodiment according to the above-mentioned basic embodiment, and includes the leading tunnel 4 and the following tunnel 8.
This can be considered as a series of operations in which two stages are set as one set, and the construction is further streamlined by one backfilling at the rear part in the above embodiment.

That is, in the above embodiment, the rear part of the leading tunnel 4 is simultaneously
Since it is also a replenishment section for materials from the ground, it is not practical as it overlaps with backfilling work.

Therefore, if these two operations are treated as one set, the lead tunnel 4
is temporarily made into a cavity, and as the subsequent tunnel 8 is excavated, it is possible to construct a backfilling mechanism with excavated earth and sand without having to worry about replenishing from the rear part.

Here, in the leading tunnel 4, segment supports 10 are installed to prevent the cavity from collapsing before the construction of the structure, and to support the excavator 3 above the leading shaft 4, and to replace the segment supports 10. and continue enforcement.

When the second succeeding tunnel 8 is excavated in this way, a third succeeding tunnel 8' is dug into the upper stage of the second succeeding tunnel 8 by similarly operating the excavator 3 and backfilling the same as described above. Then, the lower tunnel 8 is filled with a mixture of excavated earth and sand and a coagulating material such as cement, and the parts 9 of the underground structure are connected and constructed.

In addition, in the above-mentioned process, in addition to cement and water, power, water, air, etc. for the excavator 3 in the tunnels 8 and 8' in the second and higher stages are provided by connecting cables (pipes) 11, and in some cases Excess earth and sand are also discharged to the ground surface G from the uppermost succeeding tunnel 8' through a connecting pipe in a mixed state with water.

In addition, the advance of the excavator 3 follows the usual method, and the rear support 101
The reaction force may be taken from this reaction force, the reaction force may be taken from friction with the surrounding ground, or the propulsion reaction force of the hydraulic jack may be taken from the part 9 of the lower structure that has already been constructed. .

Further, it is preferable that soil concrete or the like used as a construction material contains a waterproofing agent, but a water stop plate 12 may be inserted into the pouring joint as shown in FIG.

The reinforcement of each part 9 as an underground structure is carried out using mesh reinforcements 12' as main reinforcements in the horizontal direction and secondary reinforcements in the vertical direction, and is supplemented and incorporated before backfilling with concrete. or,
In order to reduce the number of vertical saddles, it is effective to use a crimp net, and by simply adding horizontal striations, it is possible to connect the top and bottom without lap loss.

In this way, the vertical connection of each part 9 is formed as shown in FIG. 4, but of course the structure is not limited to a vertical structure, and a cross-section having an oblique curve shape is also possible.

The above embodiment is the most basic aspect of the invention of this application,
The possibilities have been explained in the order in which they occurred in principle. Next, regarding a third invention that is more practically embodied from the above-mentioned two inventions, the excavator 3, the excavation process, and the backfilling process will be explained based on FIGS. 5 and 6a to 6d. It is preferable to use a shield type excavator, which is equipped with an excavator 15 installed in front of the cylindrical casing 13 of the main body via a hydraulic jack 14, and excavates in a state where it can advance and retreat. The cement is put into a concrete mixer 17 by the conveyor 16 of the rear conveyance mechanism section 6, and the cement and water are mixed and then thrown from the backfilling mechanism section 7 to the rear of the leading tunnel 4 below.

Therefore, in response to the combination of the leading tunnel 4 and the trailing tunnel in the second invention, the third invention provides a process and equipment in the lower stage for the work in the upper stage. In detail, a sub-casing having the same diameter as the casing 13 is installed as a connecting mechanism part 18 at the starting end of the first-stage leading tunnel 4, and when the trailing shaft 8 starts, a sub-casing is installed at the lower end of the casing 13 of the excavator 3. The upper and lower parts are integrally connected via the connecting portion 19 provided.

Here, the connecting portion 19 does not directly circumscribe the two cylindrical bodies of the casing, but has a dimension that allows a distance required for connection with the previous stage.

Further, the sub-casing of the connecting mechanism section 18 communicates with the casing 13 of the main body of the excavator 3 on the upper surface, and the front working chamber 20 and the rear molding section 21 are connected to the partition wall 2 so that vertical work can be performed.
It is composed of 2.

Note that 23, 23 is a work floor having a desired entrance.

Then, the segments 24 and 11 used as supports, which had been rolled up in the leading shaft 4 by hanging down in the shaft in advance in the previous stage process, are dismantled in the front work room 20, and installed on the upper part of the casing 13 along the axial direction. The dismantled segment 24 is lifted and transported by the trolley hoist 26 on the rail 25,
In the working chamber 27 at the rear of the main body casing 13, it is transferred to the tunnel 8' following excavation and rolled up as a support 18.

In this way, the transport mechanism section 6 performs three operations: transporting excavated soil from the upper front to the lower rear, moving equipment from the lower front to the upper rear, and kneading construction materials. . In addition, a hydraulic jack 28 at the rear of the casing body 13 is used to take a propulsion reaction force to the shoring 11,
Furthermore, the hydraulic jack 2 at the bottom 29 of the sub-casing 18
8, the underground structure portion 9 below is subjected to a reaction force, and the excavation is carried out in a manner that prevents the vertically biased propulsion of all the equipment from occurring.

Next, "Concrete casing 8 whose main aggregate is the excavated soil mixed by the mixer 17"
Rear filling section 7' which is the backfilling section of trowel front working chamber 2
The mesh strips 12' supplied from the 0 side are inserted into the molded part 30' in the latter half of the sap casing turtle light, and a temporary square member 31 is buried in the upper surface.

Then, the partition wall 22 of the sub-casing 18 is used as a front formwork to be filled and connected to the lower preceding existing underground structure part 9,
In that case, the rack portion 32 of the existing underground structure portion 9 is reliably engaged and connected.

Note that 33 is a working floor, which is used for the lower segment and reinforcing mesh inside the front working chamber 20.

In addition, in the filling section 7, a pair of parallel formworks 34, 34 are provided at a predetermined interval as shown in Fig. 6c, and soil concrete filling material is placed only between the formworks 34, 34. may be backfilled to form the underground structure part 9, and the gap between the subcasing 18 and the subcasing 18 may be backfilled with excavated soil 35 to form the 6th d
It is preferable to use the structure as shown in the figure, or depending on the design, only one formwork 34 may be provided, as shown in FIG. 14, as shown in FIG. It is also possible to form the upper surface joint part of the underground structure part 9 into a concave-convex type rack by removing the square timber 31 from the mold before the soil concrete hardens. The propulsion reaction force of the excavator 3 can be reliably taken.

In this way, all the construction work in the leading tunnel 8 and the trailing tunnel 8'' using the shield type excavator 3, that is, the excavation of the upper and lower two stages, segment replacement, and backfilling, are carried out at the same time on site. This will be done simultaneously and in parallel.

The fourth invention for constructing an underground water wall structure up to an ultra-deep impermeable layer when constructing a low-temperature liquefied gas underground tank based on the above-mentioned principle invention will be described below. As shown in Figures 7 and 8, an access shaft 38 of a predetermined size is installed at a predetermined distance away from the underground tank formation site 36 that is planned to be constructed in the ground 2 until it reaches an impermeable layer located sufficiently below and deep. As shown in Fig. 7, in order to excavate the water cut-off wall appropriately from the bottom 39,
The first stage leading tunnel 4 is excavated in a circular shape by the excavator 3,
The access shaft 38 is used as a communication and starting part to connect the upper trailing shaft 8' of the second stage to the eighth stage.
As shown in the figure, excavation is carried out in parallel, and using the process described above, the support A1 is rolled up, dismantled, replaced, excavated,
Soil concrete backfilling is carried out, and the underground structure portion 9 of the water stop wall 40 is successively added upward to construct a circular structure.

During this time, power, water, air, replenishment connections for concrete, etc.
Excess earth and sand is discharged from the subsequent tunnel 8 to the access shaft 3.
8 to perform relay processing.

At this time, the tunnel excavator 3 may be raised at the starting point since the bending and stretching work returns to the starting point after each lap. It is more realistic to bend and stretch 8 in a spiral shape. That is, in this embodiment, the excavation tunnel is the only tunnel that circulates continuously in a spiral, and the above-mentioned relationship between leading and trailing is eliminated, so it can be referred to as leading part, trailing part, first stage, rear stage, etc. Become.

Of course, in each process of spiral excavation, backfilling, and pouring, the access pit 38 itself may be sequentially hardened and buried. The shield type excavator used in the above process is constructed with front and rear parts articulated around the main body, or
Alternatively, it may be bent with a predetermined curvature.

Although one excavator may be used, it is preferable to operate a plurality of excavators in a parallel state with their phases shifted.

Of course, the above-mentioned method is used for construction of waterproof concrete, reinforcement, etc., and operations such as jack reaction force due to bending and stretching, repositioning of segments, and mixing of worship services are performed by substantially the same operations.

By constructing in this way, as shown in FIG. 9, the bottom 39 of the access shaft 38 is used as a starting part and a connecting part, and the leading part and the trailing part are connected in parallel and formed in a spiral shape by the excavator 3. Finally, the 10th
As shown in the figure, a water stop wall 40 that completely surrounds the planned underground tank site 36 can be formed to reach the impermeable layer 37 and extend above ground.

Further, in the above-mentioned embodiment, one access tunnel 38 was drilled and constructed, but as shown in FIG. A first-stage starting part 41, 41, . Diagonal excavation is carried out at an angle to form the trailing shaft 8 of the adjacent leading shaft 4 until reaching the shaft 38, and then the trailing shaft 8 of the next upper stage is dug.
, 8... are excavated in parallel, so that multi-stage spiral construction can be carried out efficiently as shown in Fig. 12.

To understand this, let's take a common example: think of a three-color spiral signboard for a barber shop.

In this embodiment, when constructing a large-diameter water stop wall 40, etc., there are multiple access tunnels 38, 38, etc., so normal mining technology and tunnel technology can be applied to provide power and air supply. ,
Concrete can be brought in and replenished, and excess earth and sand can also be efficiently discharged.

In this way, by backfilling and filling each access tunnel 38, 38..., it is possible to reliably construct the underground wall 40 as shown in the exploded view in Figure 13. becomes. Note that the embodiments of the invention of this application are not only used for constructing water-stop walls for underground tanks of low-temperature liquefied gas, but can also be applied to other underground structures such as rectangular structures having access pits at the four corners. Of course there is.

In addition, if the access shaft is used as a connecting shaft during construction, it is possible to communicate with multiple locations by using a spiral rampway to the extent permitted to allow trucks and heavy equipment to be brought in and out, rather than a direct shaft with the ground. This eliminates the need for multiple access lines.

It goes without saying that the construction process, such as excavation and backfilling by vertical double connection excavation of the leading tunnel and the trailing tunnel, is not limited to only the spiral construction method.

As described above, according to the invention of this application, basically when constructing a structure in the ground, a tunnel is excavated in the ground, and the excavated soil accompanying the excavation is mixed with a coagulating material at the rear of the excavated tunnel. It is possible to partially form structures within the shaft itself by backfilling and therefore by repeating it, conventional techniques such as excavating the construction area from the surface to the crest and filling it with concrete can be achieved. The concept is completely different from that of the previous process, and it is extremely simple to launch and construct a tunnel, which uses the ground as a type of frame, and it is possible to construct underground structures without being affected by above-ground structures. A pure effect is produced.

In addition, as a further development of this construction, a subsequent tunnel is excavated above the leading tunnel by connecting it to the leading shaft in an overlapping manner, and the soil excavated in the trailing shaft is mixed with coagulation material and backfilled at the rear of the leading shaft. Based on the principle invention, underground structures can be built more rationally by simply carrying out tunnel excavation in a repeated process, and furthermore, underground structures can be constructed using only adjacent leading and trailing shafts. This has the advantage that excavated earth and sand can be used as a bone structure, making construction extremely efficient.

In addition, at least one access hole was once established in the ground, and the spiral tunnel was excavated in close proximity to each other as the leading tunnel and the following tunnel, and the backfilling work was performed as described above to excavate the access shaft. After that, just by digging a spiral shaft, just like digging from the ground surface, an underground structure will be built under a kind of automatic reflection condition.

In addition, shoring was provided for the leading shaft, and the connecting transport section between the leading shaft and the following shaft was used as a working section to backfill the excavated earth and sand from the connecting shaft with coagulation material into the rear of the leading shaft, and the shoring was replaced to construct the trailing shaft. By using the rear shoring, both tunnels are continuously reinforced by approximately one stage of shoring, making it possible to carry out work safely.

Therefore, a normal shield type excavator can be used as the construction equipment for the underground structure used for the above-mentioned construction. By having a shoring replacement mechanism and a shoring mechanism at the rear, it is set as one compact type with upper and lower tiers ~ The work of the upper and lower functions is achieved organically in parallel, and the It takes force and enables reliable excavation, and has the effect of forming and ejecting underground structures using only this device.

Furthermore, by attaching a formwork to the backfilling mechanism, there is an advantage that a structure with a designed thickness can be formed underground.

In conclusion, the invention of this application connects the horizontal work vertically instead of continuing the vertical work horizontally in order to completely eliminate the influence of the depth of underground structures constructed from the ground surface. By constructing the structure, it was possible to use basic tunnel excavation techniques from above and carry out construction work at the edge of the excavation work site. This technology can provide a completely revolutionary technology in that it can handle difficult deep-depth work using only elements in the length direction of excavation.

[Brief explanation of drawings]

The drawings show embodiments of the invention of this application, and are
Figures a, lb, and 2 are partial longitudinal cross-sectional views of Fujiri's embodiment;
Figure lb is a sectional view taken along line bb of Figure la, Figure 3 is Figure 1 m.
-m sectional view, Figure 4 is a sectional view of the underground structure shown in Figures 1 and 2, Figure 5 is a sectional view of the shield type excavator and construction, and Figures 6a, 6b, 6c, and 6d are respectively shown in Figure 5. A-A, B
-B, C-C, D-D sectional views, Figures 7 and 8 are explanatory diagrams of the underground tank water stop wall structure, Figures 9 and 10 are sectional views of the same process and underground water stop wall formation, and Figures 11 and 12 The figure is a schematic diagram of the process of constructing water stop walls for other underground tanks.
Figure 14 is a development explanatory diagram of construction, and Figure 14 is a partial sectional view of another underground structure. 2... Ground, 47 8... Mine shaft, 9...
・Structure part, 40... Structure, 4... Leading tunnel, 8
, 8'...Following tunnel, 18...Communication part, 7...
...Backfilling work section, 38...Access pit, 11
... Shoring, 13 ... Excavator body, 5 ...
... Excavation equipment, 25, 26 ... Shoring transfer mechanism, 16 ... Transport mechanism, 17. ．． ．． ... Backfilling mechanism, 14, 28, 29... Jack mechanism, 34...
...Formwork. Fig. la Fig. lb Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6a Fig. 6b Fig. 6c Fig. 6d Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Figure 14

Claims (1)

[Scope of Claims] 1. To form a tunnel in the ground, a leading shaft and a trailing shaft that can overlap and communicate with the leading shaft are excavated in parallel, and the communicating part of the trailing shaft to the leading shaft is used as a backfilling work part. 1. A method for constructing an underground structure, which comprises backfilling the rear part of a leading tunnel with soil mixed with a coagulating material from excavation of a subsequent shaft to construct a structure within the shaft itself. 2. To form a tunnel in the ground, excavate a leading shaft and a parallel trailing shaft that can overlap and communicate with the leading shaft, construct a shoring at the rear of the leading shaft, and then connect the trailing shaft to the leading shaft. At this point, the shoring is dismantled and reassembled at the rear of the trailing shaft, and the communicating section is used as a backfilling work area, and the rear of the leading shaft is backfilled with soil excavated in the trailing shaft mixed with coagulant. A method for constructing an underground structure, characterized in that the structure is constructed within the excavation shaft itself. 3. Excavate at least one access hole from the ground surface to a predetermined depth in the ground, use the access hole as a communication passage to excavate a spiral tunnel from deep underground, construct a support at the rear of the excavation, and After making a predetermined circuit, the spiral shafts overlap and communicate with each other as parallel trailing parts with the existing part of the shaft as the leading part, and in these overlapping upper and lower shafts, the shoring of the leading part is dismantled and installed in the trailing part. At the same time, the leading part is backfilled with solidified material mixed with the excavated soil of the succeeding part, and this is repeated up and down to build a cylindrical structure within the excavation shaft itself. A method for constructing an underground structure characterized by the following. 4. An underground structure construction device, the excavator body having an excavator at the tip and a shoring mechanism at the rear,
The central part is equipped with an excavated soil transport mechanism and a subsequent tunnel backfilling mechanism, and further has a propulsion mechanism for the ground, and a communication section for shoring replacement and subsequent tunnel backfilling work can be connected to the central part. An underground structure construction device characterized by comprising: 5. A device for constructing underground structures, in which the excavator body has an excavator at the tip, a shoring mechanism at the rear, and an excavated soil conveyance mechanism and a subsequent tunnel backfill mechanism in the middle. It has a propulsion mechanism for the shaft, and a communication section for shoring replacement and subsequent tunnel backfilling can be connected to the middle part, and a formwork is attached to the backfilling work section in the communication section. An underground structure construction device characterized by comprising: