JP4319064B2 - Construction method of split box and large section tunnel - Google Patents

Description

  The present invention constructs a tunnel lining body by arranging rectangular rectangular or square divisional boxes having a hollow cross-sectional view, and then constructs a large-section tunnel and uses the divisional box and the large divisional box. The present invention relates to a method for constructing a cross-sectional tunnel.

When building a tunnel underground, a retaining wall is constructed on both sides of the tunnel along the tunnel axis, the tunnel box is constructed by excavating the inside and then backfilled, and the retaining wall is removed. It is.
On the other hand, when constructing underground three-dimensional intersection tunnels under roads, railways, etc., construction by the shield method or propulsion method is generally used in order to avoid the obstacle to the ground traffic due to the above-mentioned open-cut method.

By the way, underground tunnels have become large sections due to the recent increase in traffic volume and diversification of applications of underground tunnels. When constructing such a large section tunnel, a large section tunnel is constructed by constructing and connecting a plurality of small section tunnels by a shield method (see Patent Document 1). In other words, after excavating a plurality of small-section rectangular tunnels, the steel plates that make up such small-section tunnels are removed, rebars for the main-section large-section tunnels are assembled, concrete is cast, and large-section box tunnels are placed Is to build. FIG. 5 shows an outline from the temporary construction to the main construction described above. After the ground improvement b such as chemical injection is performed between the parallel small cross-section tunnels a and a to stop the water, the internal plate that becomes an obstacle to the construction of the main tunnel c is removed, and then the small cross-section tunnels a and a For example, non-shrinking mortar is filled or caulked. After constructing a double and triple water stop structure by such water stop construction, the construction shifts to the construction of the main tunnel c.
JP 2001-214699 A

The conventional large-section tunnel construction method has the following problems.
<1> After constructing the lining body by arranging each divided box side by side, the construction shifts to the construction of the large section tunnel of the main construction. It is necessary to remove the outer peripheral wall. Here, if all of the divided boxes have four outer peripheral surfaces, the quantity to be removed becomes enormous, so that problems such as a longer construction period and a higher removal cost may occur.
<2> In the above problem, when the outer peripheral surface of the divided box is a steel plate (for example, a skin plate), the scrap plate is scrapped and the scrap cost increases. Problems can also arise.

In order to solve the above problems, the split box of the present invention is a split box used for construction of a large cross-section tunnel, and the outer peripheral surface of the split box having a hollow or rectangular cross section is shown. The four surfaces are composed of a plurality of plate-shaped beam members intersecting in a grid pattern, and the division box that digs in advance covers the outside of the four plate-shaped beam members with a plate-shaped surface member , The divided box that is lined up and dug is configured by covering the outside of the plate- like beam member with a plate-like surface member except for the side that contacts the divided box that was dug in advance.

The construction method of the large-section tunnel of the present invention is a construction method of a large-section tunnel in which a large-section tunnel is constructed after constructing a tunnel lining body by arranging divided boxes side by side, A plurality of divided boxes covering the plate-like surface members are installed in the tunnel direction to construct the preceding divided box row, and the preceding divided box row side crosses the plurality of plate beam members in a lattice shape. And constructing a succeeding segmented box consisting of a segmented box not provided with plate-like surface members in parallel with the preceding segmented box, It is characterized in that a large section tunnel of a main construction is constructed after sequentially constructing a lining body made up of the division box rows in parallel with the division case rows of the previous construction.

The division box and large-section tunnel construction method of the present invention can obtain at least one of the following effects by means for solving the above-described problems.
<1> In the divided boxes that are arranged side by side, since only one surface member is provided on each of the opposing side surfaces (or upper and lower surfaces), the number of removed divided box members that obstruct large-section tunnel construction Can be significantly reduced. The effect of reducing the number of removed parts becomes larger as the cross section of the tunnel becomes larger and the number of divided boxes constituting the lining body increases, and as the tunnel extension becomes longer.
<2> Since the plate-like surface member and plate-like beam member are generally made of steel, the scrap processing quantity is reduced by reducing the removal quantity as described above, which leads to a reduction in scrap cost. .

<1> Overall configuration The present invention is constructed after a plurality of divided boxes 1 are arranged in parallel by a shield method or a propulsion method to form an earth retaining structure (covering body 10) for construction of a large section tunnel 7. This relates to a construction method for constructing a large-section tunnel 7 and a split box 1 used at that time.
Hereinafter, an embodiment in the case where the lining body 10 is constructed by arranging four (row) divided boxes 1 in parallel will be described (see FIG. 1). Of course, it is possible to construct the lining body 10 by arranging five or more divided boxes 1 in parallel, the dimensions of the large-section tunnel 7 to be constructed, the dimensions of the divided box 1, and the excavation used. The collocation radix of the divided boxes 1 can be selected as appropriate from the size of the machine.

The divided box 1 used in the present invention is a rectangular or square divided box having a hollow cross-sectional view as will be described later, and a plurality of plate beam members 2 whose four outer circumferential surfaces intersect each other in a lattice shape. It is composed of. The plate-like beam member 2 can be manufactured from a thin steel plate whose thickness is relatively thin, and its width (back when used as a beam) and thickness can be determined by required strength. As described above, the purpose of forming the surface by crossing the steel plate materials in a lattice shape is better in removal workability compared to, for example, a concrete divided box, and the removal quantity (weight) is much less. It is to become. Further, as will be described later, the divided boxes 1 having different configurations are arranged in parallel with the existing divided boxes 1 according to the construction order.
First, using a machine for digging a rectangular section, one divided box is constructed while sequentially installing a plurality of divided boxes over the tunnel extension.
When constructing with a single excavator, install the divided box trains one by one over the tunnel extension one by one, and when using multiple excavators, install one split box train sideways or up and down during construction. It is also possible to carry out the construction of the divided box rows arranged in parallel at the same time. Here, the side-by-side arrangement includes not only parallel arrangement on the left and right but also the case of parallel arrangement on the top and bottom.
As shown in FIG. 1, the construction sequence when the cross section of the lining body 10 is constituted by four divided boxes 1 is, for example, an A divided box 1, a B divided box 1, a C divided box 1, and a D divided. Construction can be performed in the order of the box 1 (A divided box 1, C divided box 1, B divided box 1, D divided box 1 may be used).
After constructing the earth retaining structure (lining body 10) with the plurality of divided boxes 1, it is possible to shift to the construction of the large-section tunnel 7. In other words, after the outer wall of the lining body 10 and the water separation treatment such as ground improvement is applied to the separation part between the divided boxes 1, the reinforcing bars / framework for constructing the main large-sized tunnel 7, concrete After placing through the concrete curing period, the divisional box components exposed to the tunnel interior are removed.

Here, as the excavator to be used, it is preferable to use an excavator having a rectangular front face shape so that a propelling pipe having a rectangular cross section can be installed (not shown). The surface plate can be configured with a plurality of rocking cutters described later around the rocking axis in the direction of the excavation axis. The plurality of swing cutters can be controlled so as not to overlap each excavation range. That is, for example, two oscillating cutters are arranged in the same plane or both so as to move back and forth, and each oscillating cutter is excavated only in its own range of ownership. When excavating a rectangular cross section, the rectangular cross section can be equally divided into two, for example, and the ground can be cut while the two rocking cutters rock within each divided range. In this case, the swing of the swing cutter can be controlled so as to swing in directions opposite to each other about the swing shaft.

<2> Division box The division box 1 uses the division box 1 from which the structure differs according to the order of construction. An embodiment in which the lining body 10 is configured from four divided boxes 1 will be described below.
The divided box 1 is formed into a rectangular or square shape with a sectional view, and the four surfaces constituting the divided box 1 are formed by crossing a plurality of plate beam members 2 in a lattice shape. The plate-like beam member 2 is composed of a relatively wide surface (a surface that becomes the back of the beam when used as a beam member) and a relatively thin surface. A plurality of plate-like beam members 2 are crossed in a lattice shape while facing the outer peripheral surface. The plate-like beam member 2 is preferably made of a steel material.

  Here, the divided box 1 (A-divided box 1 in FIG. 1) first installed in the ground is plate-like on the surface of the frame of the plate-like beam member 2 intersected in a lattice pattern on all four sides. The surface member 3 is fixed (see FIG. 2). In addition, as shown in FIG. 1, a split box 1 (B-split box 1 and C-split box 1) is installed on the left and upper sides of the A-split box 1. And the groove 5 in which the protrusion 6 (refer FIG. 3) with which the C division box 1 was equipped can be engraved in the state extended in the tunnel direction in the upper surface and left side surface of the A division box 1. (See FIG. 2). Such protrusion 6 (or protrusion) is also preferably made of a steel material.

  It should be noted that the end side constituting the outline of the divided box 1 and the end side constituting the surface not covered by the plate-like surface member 3 among the end sides in the tunnel axis direction can be formed by the square tube 4. it can. Thus, by reinforcing the surface without the plate-like surface member 3 with the square tube 4, it becomes possible to transmit the thrust evenly. That is, the surface with the plate-like surface member 3 is such a surface member, and the surface without the plate-like surface member 3 is transmitted by a relatively rigid square tube 4 extending in the tunnel axis direction. The rigidity of the surface (tunnel axial rigidity) can be made substantially uniform, so that the thrust transmission performance can be made uniform.

The B-divided box 1 installed on the left side of the A-divided box 1 has three surfaces excluding the surface on the A-divided box 1 side of the surface of the frame of the plate-like beam member 2 crossed in a lattice shape. It is set as the structure which fixed the plate-shaped surface member 3 to. Out of the four surfaces of the B-divided box 1, on the surface on the A-divided box 1 side, a ridge 6 that can be fitted in the groove 5 engraved on the side surface of the A-divided box 1 is extended in the tunnel direction. The groove 5 is engraved on the upper surface on the D-divided box 1 side.
By adopting such a configuration, one plate-like surface member 3 is provided on the opposing surfaces of the A-divided box 1 and the B-divided box 1 (only the side surface of the A-divided box 1). The removal quantity of can be halved.

  The C-divided box 1 installed above the A-divided box 1 excludes the surface (lower surface) on the A-divided box 1 side from the surface of the frame of the plate beam member 2 intersected in a lattice shape. The plate-like surface member 3 is fixed to the three surfaces. Further, on the lower surface, a ridge 6 that can be fitted into the groove 5 carved on the upper surface of the A-divided box 1 is installed in a state extending in the tunnel direction.

  The D division box 1 to be installed last has a configuration in which the plate-like surface member 3 is provided on two surfaces excluding the two surfaces on the B division case 1 side and the C division case 1 side. A protrusion 6 that can be fitted into the groove 5 engraved on the upper surface is installed on the lower surface (see FIG. 3).

  Since each divided box 1 is configured as described above, the number of face members is greatly reduced because the divided box 1 and 1 that are arranged side by side do not have plate-like surface members 3 that face each other. In addition, it is possible to realize construction with high installation accuracy because the protrusions 6 of the divided box 1 to be installed downstream are fitted in the grooves 5 of the divided box 1 to be installed in advance. .

Further, as another embodiment, the divided box 1 can be manufactured by forming all the edges constituting the outline of the divided box 1 with the square tube 4. By making the outer shell all reinforced with, for example, a steel square tube 4, the extension of one split box 1 can be lengthened. In this way, if the extension of one split box 1 can be lengthened, the number of removed members of the split box 1 that becomes an obstacle when the large-sized tunnel 7 is constructed can be reduced. In addition, in FIG. 4, the division box 1 which consists of this embodiment is shown for the D division box 1 as an example.

Hereinafter, the construction method of the large-section tunnel of the present invention will be described with reference to FIG.
Using a rectangular cross-section excavator, a split box row composed of a plurality of A split boxes 1 is installed in the ground. When starting the excavator, a shaft is constructed at a point away from the railway line or road intersection on the ground, or an approach section leading from the ground to the underpass is excavated obliquely downward.
When constructing the lining body 10 with a single excavating machine, a split box body composed of the A split box 1 is completed over the extension of the tunnel. When constructing the lining body 10 with two or more excavating machines, when the construction of the split box body consisting of the A split box 1 has progressed to some extent, the split consisting of the B split box 1 juxtaposed to it Construction of a box sequence (or a divided box sequence consisting of C-divided boxes 1) can be started.

Next, the post-installed B-divided box 1 that is juxtaposed on the left side of the previously installed A-divided box 1, and the ridge 6 provided on the right side of the B-divided box 1 are connected to the A-divided box 1. Are arranged side by side while being fitted in the groove 5 provided on the right side of the.
When the construction of the split box series consisting of the B split box 1 is completed, the split box series consisting of the C split box 1 and the split box series consisting of the D split box 1 are similarly constructed. .

When the construction of the lining body 10 is completed, from the inside of the lining body 10, for example, a cement-based solidifying material or a resin-based chemical solution is filled into the outer portion of the lining body 10 and between the division boxes 1. Apply water stop treatment.
Thereafter, rebars and molds for constructing the main large-sized tunnel 7 are assembled, and concrete is placed to construct the large-sized tunnel 7.
After the curing period of the concrete has passed, the divided box 1 constituent members protruding into the tunnel are removed.

Sectional drawing which showed the state which arranged the division | segmentation box of this invention 4 units | sets (row) side by side. The perspective view which showed the division | segmentation box (A division | segmentation box) installed initially among the four division | segmentation boxes of FIG. The perspective view which showed the division box (D division box) installed last among the four division boxes of FIG. The perspective view which showed other embodiment of D division box. Explanatory drawing which was the conventional construction method, and showed the condition which is constructing the large section tunnel using the division | segmentation box of 4 units | sets (row | lines).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Divided box 2 ... Plate-shaped beam member 3 ... Plate-shaped surface member 4 ... Square tube 5 ... Groove 6 ... Projection 7 ... ..Large section tunnel 10 ... lining body

Claims (4)

A split box used for construction of large section tunnels,
The four surfaces constituting the outer peripheral surface of the rectangular or square division box having a hollow cross-sectional view are configured by intersecting a plurality of plate-like beam members in a lattice shape,
The division box which advances ahead is covered with the plate-shaped surface member outside the plate beam member of the four surfaces,
The division box that is followed and excavated is configured by covering the outside of the plate- like beam member with a plate-like surface member , except for the side that contacts the division box that has been excavated in advance.
Split box.
Provided with grooves extending in the tunnel direction on the outer peripheral surface of the preceding division box,
On the outer peripheral surface of the divided box to be placed side by side, provided with ridges or protrusions that can be fitted into the grooves of the preceding divided box,
The divided box according to claim 1.
It is a construction method of a large section tunnel that constructs a large section tunnel after constructing a tunnel lining body by arranging divided boxes,
A plurality of divided boxes formed by coating plate-like surface members on all four sides are installed in the tunnel direction to construct a preceding divided box row,
The preceding divided box row side is formed by intersecting a plurality of plate beam members in a lattice shape, and precedes a divided box row that consists of divided boxes not provided with plate-like surface members. Constructed side by side in divided box rows,
Sequentially put the divided box rows that follow into the divided box rows of the previous construction,
After constructing the lining body consisting of split box rows,
It is characterized by building a large section tunnel of the main construction,
Construction method of large section tunnel. In the construction method of the large-section tunnel according to claim 3,
In the groove extending in the tunnel direction provided on the outer peripheral surface of the preceding split box,
Install the split box that follows the preceding split box while fitting the protrusions or protrusions on the surface of the preceding split box on the outer peripheral surface of the split box that is placed side by side. It is characterized by
Construction method of large section tunnel.

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