JPH1136338A - Construction method of underground structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the occupied area of the ground surface and prevent noise and vibration, by excavating ground down to a specified depth to form an underground space and covering the upper part of the space with a covering body and then, excavating downward the ground from the underground space by an excavating means arranged in the space. SOLUTION: A shaft H excavated from the road face R is covered with a covering body 5. A crane frame 10 is installed after the shaft has been excavated and an underground space A has been formed. And further, the underground space A is excavated down to a specified depth and a pressing-in device 20 is set. Subsequently, a clamshell 25 is fitted to the attachment 13 of the crane frame 10 and caisson bodies C2, C3 are constructed on a caisson body C1 while excavating the inside ground G of a caisson C in water and discharging excavated soil. And the pressing-in device 20 is settled. In this way, an underground space covered with a covering body 5 to construct an underground structure can be obtained. And the occupied area of the road face can be minimized and diffusion of noise and vibration to the surrounding zone can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing an underground structure suitable for use in, for example, starting a shield tunnel, reaching a shaft, or constructing a bridge foundation.

[0002]

2. Description of the Related Art As is well known, underground structures that are continuous in the vertical direction, such as starting and arriving shafts for shield tunnels for sewerage, foundations of bridges, etc., must be excavated from the ground surface with a drilling machine. Has been built by. As one of the construction methods of such an underground structure, there is a so-called open caisson method in which a caisson having a predetermined shape is sunk into the ground and the ground inside is excavated.

[0003]

However, the conventional method of constructing an underground structure as described above has the following problems. In recent years, shield tunnel construction has been widely adopted in urban areas, and the above-mentioned shafts have been forced to be constructed on arterial roads with heavy traffic or in residential areas where private houses are lined up around. In such a case, there is a problem that complaints about the occurrence of traffic congestion due to occupation of the road surface and noise and vibration caused by the construction work cannot be avoided.

When an open caisson method is used to construct an underground structure, a clam shell attached as an attachment such as a crawler crane is used for excavating earth and sand inside the caisson. Then, there is a problem in that a work yard covering a wide area is required on the ground surface, and the occupied area on the ground is further increased.

The present invention has been made in consideration of the above points, and reduces the occupied area on the ground while reducing noise and noise.
An object of the present invention is to provide a construction method of an underground structure capable of minimizing the influence on the surroundings while suppressing the occurrence of vibration and the like.

[0006]

The invention according to claim 1 is
This is a method of constructing an underground structure that is continuous in the vertical direction, such as a shaft, where the ground is excavated to a predetermined depth to form an underground space, and the upper part of the underground is covered with a lining body. The underground structure is constructed by excavating the ground downward from the underground space with the arranged excavating means.

According to a second aspect of the present invention, in the method of constructing an underground structure according to the first aspect, a cylindrical caisson is submerged in the ground for constructing the underground structure downward from the underground space. An open caisson method is used to excavate the ground inside the caisson, and the caisson subsidence means is also arranged in the underground space.

According to a third aspect of the present invention, in the method of constructing an underground structure according to the second aspect, a hydraulic jack is used as the sinking means of the caisson.

The invention according to claim 4 is the invention according to claims 1 to 3
The method of constructing an underground structure according to any one of the above, further comprising disposing a horizontally movable overhead crane below the lining body.

According to a fifth aspect of the present invention, in the construction method of an underground structure according to the fourth aspect, the overhead crane is provided with a clamshell, and the ground is excavated by the clamshell.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a method for constructing an underground structure according to the present invention; FIG. Here, a shaft of a shield tunnel will be described as an example of an underground structure to which the method of constructing an underground structure according to the present invention is applied.

As shown in FIG. 1, to construct a shaft,
First, a predetermined number of parent piles 1 are cast from the ground surface into, for example, a rectangular shape in plan view. Next, the ground G inside the portion surrounded by the parent pile 1 is excavated from the road surface R by the excavator 2. This excavation work is basically performed only at night when traffic volume is low, and during the daytime, the lining girder 3
And a lining plate 4 of the same level as the road surface R laid on the lining girder 3
The excavated pit H is covered with a lining body 5 composed of the following so as not to hinder traffic.

As shown in FIG. 2, when the excavated pit H reaches a depth at which the backhoe (digging means) 6 and the like can work therein, the backhoe 6 and the anchor driving machine 7 Etc. are put into the pit H. Thereafter, the pit H is always covered with the lining body 5.

Thereafter, below the lining body 5, the pit H is dug further downward by the backhoe 6, and the ground anchors 8,
8 …… is placed and the mountain is secured.

As shown in FIG. 3, when a pit H is excavated to a predetermined depth and an underground space A is formed below the lining body 5, a portal crane mount (overhead crane) is formed in the underground space A. 10 is installed. The crane gantry 10 has legs 11, 11 that can move in a horizontal direction along a rail (not shown) laid on the bottom surface of the underground space A, and is orthogonal to the moving direction of the legs 11 below the lining body 5. It comprises a guide rail 12 extending in the horizontal direction, and an attachment 13 movably provided along the guide rail 12.

In addition, below such a crane base 10, a ground anchor 15 is driven by the anchor driving machine 7 from the bottom surface of the underground space A into the ground G below.

Next, as shown in FIG. 4, the bottom surface of the underground space A is excavated to a predetermined depth, and the replacement sand is laid there to construct a mound 16. Subsequently, on the mound 16, for example, a blade port C0 of a caisson C and a first lot caisson body C1 corresponding to the shape of a vertical shaft to be constructed, each having a rectangular shape in plan view, are constructed.

Subsequently, as shown in FIGS. 5 and 6, a press-fitting device (subsidence means) 20 for press-fitting the constructed caisson C into the ground G is set. This press fitting device 20
B-shaped support plate 21 set on caisson C in plan view
And a supporting girder 22 disposed at each of the four corners on the supporting plate 21 and a hydraulic press-fitting jack 23 such as a center hole jack. Each bearing girder 22 has a pair of two girder members 22a arranged diagonally so that both ends protrude from the supporting plate 21. At each end, two girder members 22a, The upper end of the ground anchor 15 is inserted between the 22a, and a press-fit jack 23 is attached to the upper end of each ground anchor 15.

In such a press-fitting device 20, the press-fitting jacks 23 and the support plate 21 are obtained by simultaneously operating the press-fitting jacks 23 to obtain a reaction force on the ground anchor 15.
, The caisson C is lowered and sinks into the ground G.

As shown in FIG. 7, after the press-fitting device 20 is set, the ground G inside the caisson C is excavated with the backhoe 6, and the soil is discharged by the steel bucket 24 attached to the attachment 13 of the crane gantry 10. The caisson C is sunk into the ground G by the press-in jack 23 of the press-in device 20.

Thereafter, the above operation is continued, and the press-fitting device 20
The ground G is excavated with the backhoe 6 inside the caisson C while the caisson C is sinking, and the excavation by the backhoe 6 is stopped when the ground G is excavated to the groundwater level L.

Subsequently, as shown in FIG.
A clamshell (digging means) 25 is attached to the attachment 13 of the crane gantry 10. After that, while the ground G inside the caisson C is excavated and excavated by the clamshell 25, the caisson body C2 of the second lot and the caisson body C3 of the third lot are put in the underground space A in the first lot. Are sequentially constructed on the caisson frame C1 of the
And let it sink.

When the caisson C has been laid down to a predetermined depth and the ground G has been excavated to a predetermined depth in this way, the press-in device 20 and the like are removed, and as shown in FIG. The outer periphery of caisson C projecting upward from the bottom surface of A is backfilled to its upper end level. Then, concrete 29 is poured into the bottom of the shaft (underground structure) V with a tremy tube 28 underwater to form a bottom plate, and the inside of the shaft V is dried up. As a result, the shaft V having a predetermined depth is constructed. Thereafter, the shaft V is started and the tunnel is excavated by the shield method or the like as the reaching shaft.

In the construction method of the shaft V described above, the shaft V is constructed by the open caisson method from the underground space A whose upper part is covered with the lining body 5. This minimizes the occupation of the road surface even when there are roads on the ground, and suppresses the occurrence of traffic congestion and the spread of noise and vibration due to construction work to the surroundings, thus affecting the surrounding environment. Can be minimized. Moreover, by performing the work in the underground space A covered with the lining body 5, the construction of the shaft V can be advanced day and night, thereby shortening the construction period and reducing the cost.

Since the blade C0 and the caisson skeletons C1, C2,... Constituting the caisson C are also constructed in the underground space A, concrete can be cast in the air, and quality control can be performed easily and reliably. it can. In addition, such a caisson C has an advantage of being excellent in water stoppage.

Further, since the hydraulic press-in jack 23 is used for the press-in device 20 for sinking the caisson C, the generation of noise and vibration can be suppressed in this respect as well.

In addition, since the portal crane base 10 is provided below the lining body 5, the space in the underground space A can be used more effectively than when a crawler crane or the like is used. . And this crane stand 1
With 0, it is possible to excavate earth and sand and carry in equipment and materials. Moreover, since the ground G below the groundwater level is excavated by the clamshell 25 provided on the crane gantry 10,
Even when the ground G is a cobble ground where it is usually difficult to apply the open caisson method, it is possible to construct the shaft V by excavating the ground G without any problem. In addition, by performing underwater excavation, it is possible to suppress the occurrence of problems caused by groundwater such as bulging and boiling.

In addition to this, the underground space A is formed by the parent pile 1 and the earth anchor 8, so that there is no support for cutting beams and the underground space A can be secured to the maximum.

In the above embodiment, the caisson C has a rectangular shape in cross section, but the shape may be any shape. In addition, although the parent pile 1 and the earth anchor 8 are used to form the underground space A, it goes without saying that, for example, an underground continuous wall or a self-standing sheet pile may be used. Furthermore, in the said embodiment, although the construction method of the underground structure which concerns on this invention was made into the structure applied to the shaft V, for example, if it is an underground structure continuous in the up-down direction, for example, a bridge foundation etc. It is also possible to apply the same to the above structure.

Other than this, any configuration may be adopted as long as it does not depart from the gist of the present invention, and it is needless to say that the above-described configurations may be appropriately selectively combined. No.

[0031]

As described above, according to the method of constructing an underground structure according to the first aspect, the ground is excavated to a predetermined depth to form an underground space, and the underground space is covered with a lining body. After the construction, the underground structure is constructed by digging the ground downward with the digging means arranged in the underground space. In this way, by setting the working space for constructing the underground structure as an underground space covered with a lining body, even when there is a road on the ground, the occupation of the road surface can be minimized, The occurrence of traffic congestion and the diffusion of noise and vibration to the surroundings can be suppressed, and the influence on the surrounding environment can be minimized. Moreover, by performing the work in the underground space covered with the lining body, it is possible to shorten the construction period and thereby reduce the cost.

According to the construction method of the underground structure according to the second aspect, the open caisson method is used for the construction of the underground structure, and the caisson subsidence means is also arranged in the underground space. Since the caisson skeleton can be constructed in the underground space using the open caisson method in this way, concrete can be cast in the air, and quality control can be performed easily and reliably. Further, such a caisson body has an advantage that it is also excellent in waterproofness. Furthermore, according to the construction method of the underground structure according to the third aspect, since the hydraulic jack is used as the caisson sinking means, it is possible to suppress the generation of noise and vibration in this respect as well.

According to the construction method of an underground structure according to claim 4, an overhead crane movable in a horizontal plane is provided below the lining body. By using the overhead crane in this way, the space in the underground space can be effectively used. And this overhead crane
It can also be used for excavating earth and sand and carrying in equipment and materials.

According to the construction method of the underground structure according to the fifth aspect, the overhead traveling crane is provided with the clamshell, and the ground is excavated by the clamshell. By using a clamshell, the above method can be applied to a cobblestone ground where it is usually difficult to apply the open caisson method. In addition, underwater excavation can be performed, and occurrence of problems such as bulging and boiling caused by groundwater can be suppressed.

[Brief description of the drawings]

FIG. 1 is a view showing a method of constructing a shaft by applying a method of constructing an underground structure according to the present invention, and is an elevational sectional view showing a process of forming an underground space.

FIG. 2 is an elevational sectional view showing a state where a lining body is installed.

FIG. 3 is a vertical sectional view showing a state where the overhead crane is installed.

FIG. 4 is an elevational sectional view showing a state in which the sinking means is installed in the caisson constructed in the underground space.

FIG. 5 is a plan view of FIG. 4;

FIG. 6 is a sectional view taken along the line II of FIG. 5;

FIG. 7 is a view showing a method of constructing the shaft,
It is an elevation sectional view showing the state where the ground was excavated to the groundwater level.

FIG. 8 is an elevational sectional view showing a state where the caisson is sunk and the ground inside the caisson is being excavated with a clamshell.

FIG. 9 shows a state where the sinking of the caisson is completed and concrete is poured into the bottom of the caisson.

[Explanation of symbols]

 Reference Signs List 5 lining body 6 backhoe (excavation means) 10 crane base (overhead crane) 20 press-in device (subsidence means) 25 clamshell (excavation means) A underground space C caisson G ground V shaft (underground structure)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI E21D 1/03 E21D 1/08 1/08 9/06 301E 9/06 301

Claims (5)

[Claims] 1. A method for constructing an underground structure, such as a shaft, continuously extending in a vertical direction, wherein the ground is excavated to a predetermined depth to form an underground space, and the underground space is covered with a lining body. A method for constructing an underground structure, wherein the underground structure is constructed by excavating the ground downward from the underground space using excavating means arranged in the underground space. 2. The method of constructing an underground structure according to claim 1, wherein, in the construction of the underground structure downward from the underground space, a cylindrical caisson is settled in the ground while the caisson is set in the ground. An underground structure construction method, wherein an open caisson method for excavating the ground is used, and the caisson subsidence means is also arranged in the underground space. 3. The method of constructing an underground structure according to claim 2, wherein a hydraulic jack is used as the caisson subsidence means. 4. The underground structure according to claim 1, further comprising a horizontally movable overhead traveling crane below the lining body. The construction method of things. 5. The method of constructing an underground structure according to claim 4, wherein the overhead crane is provided with a clamshell, and the ground is excavated by the clamshell.