JPH11336102A - Foundation structure for underwater tunnel and its construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a crushed stone foundation and a mortar foundation by installing a base on piles provided on the water bottom, and installing support beds supporting the caisson of an underwater tunnel on the base. SOLUTION: A base 231 is supported by preceding foundation piles 233 and succeeding foundation piles 234, and support beds 232 are arranged on it. The piles 233 are positioned by an MN leader and erected and driven in the water. A crane ship is guided by a GPS and moored for installing the base 231, the base 231 is guided by the GPS, and it is hoisted via a suspension frame and lowered to the prescribed height. The reference columns of the suspension frame are held by the MN leader and installed so that the piles 233 enter the preceding foundation pile holes 235 of the base 231. The piles 234 are hoisted and inserted into succeeding foundation pile holes 236 and driven. No crushed stone foundation is required, the processing of floating mud is not required during execution, and the work on the sea can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to construction of an underwater tunnel by extruding a box.

[0002]

2. Description of the Related Art Conventionally, in the basic structure of an underwater tunnel, like a submerged tunnel, crushed stone and mortar are filled between a box and the seabed.

However, the basic structure of a conventional underwater tunnel has the following problems. <A> A large amount of crushed stone and mortar are required. <B> In order to prevent marine pollution, it is difficult to treat floating mud flowing into trenches during construction. <C> There is a possibility that a gap is formed between the box and the ground. <D> There are many operations from the sea, which affects the navigation of ships.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a basic structure and a method for constructing an underwater tunnel.

[0005]

According to the present invention, there is provided a foundation for an underwater tunnel, wherein a support is installed on a pile provided on the underwater floor, and a support for supporting a box of the underwater tunnel is installed on the support. Provide structure.

Further, a positioning pile is provided on the bottom of the water, a support for supporting the box of the underwater tunnel is installed on the positioning pile, the support is positioned, and thereafter, a post-pile is provided to support the support. And a method of constructing a basic structure of an underwater tunnel.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of construction of a submarine tunnel according to the present invention will be described with reference to the drawings.

<A> Construction of water stop wall First, a trench for installing a group of boxes is excavated at the bottom of the water area 100. After placing the earth retaining sheet pile along the edge of the excavation planning line in the land-based trench, as shown in FIG.
A double deadline 102 is constructed near the shore side of. And
The inside of the earth retaining steel sheet pile is excavated, and a groove 103 is excavated from the starting coastal area to the double deadline 102 as shown in FIG.

[0009] The shape of the groove 103 is excavated in accordance with the design shape of the underwater tunnel. In this embodiment, however, in order to explain the case of constructing a concave arc-shaped tunnel,
The groove 103 is also excavated in a concave arc shape correspondingly.

Next, as shown in FIG. 7, a water stop wall 200 is constructed at a position where the water is flooded by a predetermined distance from the starting shore. The construction position of the water stop wall 200 may be constructed at a depth where the entire housing can be submerged. For example, as shown in FIG. 1, the water stop wall 200 is formed in a gate shape by providing an opening for passing a group of boxes in the excavated groove 103, and the size of the opening is a cross section of the box. Design slightly larger than the external shape.

A water-stopping member, such as a wire brush, is provided on the inner surface of the opening to contact the peripheral surface of the box. When the water depth at the construction position is shallower than the water depth at which the entire case is immersed, the water stop wall 200 may simply be provided with column members on both sides of the case.

<B> Construction of Extruding Yard and Manufacturing Yard As shown in FIGS. 1 and 2, from the water blocking wall 200 to the land, the extruding yard 300 and the manufacturing yard 310 are sequentially arranged. The two yards 300, 310 are provided so as to be on the extension of the concave arc of the groove 103. Also, production yard 3
A temporary storage space 320 for materials and the like is provided on a flat surface portion on the land side of 10. And on those slopes, there are water casters.
And the like. In addition, extrusion yarn
In the vicinity of the boundary between the arm 300 and the manufacturing yard 310, a gate-type or other braking reaction force receiving wall 220 as shown in FIGS.
Or build beams.

Conventionally, extrusion jar 300 and fabrication jar
The yard 310 is provided on the land along the coast of the water body. However, as in the present invention, the water level is lowered by installing the water stop wall 200, and these yards are provided in the body of water to form a box group. The extrusion distance can be shortened.

<C> Installation of Sliding Bearing As shown in FIGS. 1 and 7, sliding bearings 230 are installed at predetermined intervals along the bottom surface of the groove 103. As an example of the slide bearing 230 constructed underwater, a steel-frame concrete base is supported by a steel pipe pile, and a slide plate having an iron plate or the like is attached to the surface of the base. Details of the sliding bearing 230 of the present invention will be described later.

<D> Manufacture and pre-extrusion of box In a manufacturing yard 310, a box 400 of a reinforced concrete structure or a composite structure of a steel shell type is manufactured in a dry state. In the box 400, one block is manufactured on a manufacturing yard 310 in a block-by-block manner, and concrete is sequentially joined to form a predetermined number of block groups continuously and integrally. For example, they are integrally manufactured in units of 100 blocks of 10 blocks, pre-stress is introduced, and the connection between the blocks of 10 blocks is made by a joint or the like.

1 and 2, for example, assembling and welding a bottom plate steel plate 401, assembling a bottom plate reinforcing bar 402, placing a bottom plate 403 in concrete, and side wall reinforcing bars 404, as shown in FIGS. Assembly of the side wall 405
, Concrete assembling of the upper floor slab 406, concrete laying of the upper floor slab 407, attaching of the waterproof sheet 408, and placing of the protective concrete 409.

A box 400 sequentially manufactured as described above
Until the original extrusion device 250 is installed, extrusion is performed by a temporary extrusion device. For example, the water blocking wall 20
Using a center-hole jack installed at the lower part of the box 0, the bottom plate 403 is pulled with a strand of PC steel, and pre-extrusion work is performed until the tip of the box 400 penetrates the braking reaction force receiving wall 220.

<E> Initial Extrusion of Box When the tip of the box 400 has passed through the braking reaction force receiving wall 220, the original extruder 250 is installed. As a specific example, as shown in FIGS. 1 and 7, a tip device such as a hand girder 410 is attached to the tip bulkhead. Next, as shown in FIGS. 1 and 2, a predetermined number of PC steel wires 240 are stretched between the water blocking wall 200 and the braking reaction force receiving wall 220, and the extrusion device 250 is mounted on the way. .

FIG. 3 shows a specific example of the extrusion device 250.
As shown in FIG. 5, a pair of center ball jacks 251 and 252 capable of holding and releasing the PC steel strand 240 are used. These are installed by fixing the movable gantry 253 to a recess provided in the upper floor slab 407 of the box 400.

After the box 400 has penetrated the braking reaction force receiving wall 220, the box 400 is
The initial extruding operation is performed until the tip of the pierce through the water stop wall 200. As shown in FIGS. 3 to 5, the center ball jacks 251 and 252 operate while moving one of the jacks at the same time as the other while contracting and releasing the wedges at both ends of the jacks alternately. 253 is moved to extrude the box 400. When the pushing device 250 approaches the water blocking wall 200, the pushing device 250 is replaced on the reaction force receiving wall 220 side, and the above operation is repeated.

<F> After the water injection box 400 penetrates the water blocking wall 200, as shown in FIG. 8, the seawall 101 is removed, the groove 103 is extended, and the sliding bearing 230 is installed in the same manner as described above. Do it by the way. Next, the double deadline 102 is removed and water is injected. At this time, water does not enter into the extrusion yard 300 and the manufacturing yard 310 due to the water blocking wall 200.

Next, the water blocking wall 20 is inserted into the extrusion jar 300.
Water is injected at a water level lower than the water area outside
By reducing the water pressure acting on the front surface, the force required for pushing out the box 400 group is reduced, and the box group 400 is set so as not to be pushed back to the extrusion yard 300 side. That is, the inclination of the manufacturing yard 300 and the moving box 4
Due to the coefficient of friction with the sliding bearing 230 supporting the weight of the group 00, the group of boxes 400 is stopped even when the water pressure from the outside water area acts.

<G> Box Extrusion Work The production and extrusion of the box 400 are repeated as described above, and the group of boxes 400 is extruded along a concave arc. And
As shown in FIG. 9, the tail end of the group of boxes 400
Extrude until reaching just before zero, and complete the extruder.
After that, as shown in FIG. 10, the pushing device 250 and the braking reaction force receiving wall 220 are removed. If the starting point of the underwater tunnel is different from the extrusion completion position, the tip of the group of boxes 400 is pulled in from the opposite side of the water area as necessary, and joined to a land tunnel or the like on the opposite side. The tail end of the group of boxes 400 moves to the starting point of the extrusion tunnel.

Next, the revetment 104 is restored and the backfill 105
After draining the inside of the earth retaining part, facilities such as the water stop wall 200, the friction reducing device 210, and the sliding bearing 230 on the land side from the starting point of the extrusion tunnel are removed. The sliding bearing 230 installed at the bottom of the extrusion tunnel is not removed and is left as a support for the tunnel. This completes the underwater tunnel extrusion work.

Hereinafter, the sliding bearing according to the present invention will be described.

<A> Sliding Bearing (Basic Structure of Underwater Tunnel) The sliding bearings 230 are installed at predetermined intervals along the bottom surface of the groove 103 as shown in FIG. The slide bearing 230 to be constructed in the water serves as a foundation structure of the underwater tunnel. Specifically, as shown in FIGS. 11 to 14, the support body 231 is supported by the preceding foundation pile 233 and the following foundation pile 234, The support 232 is arranged on the support 231.
The leading foundation pile 233 and the trailing foundation pile 234 may be any as long as they can support the foundation structure of the underwater tunnel. For example, a steel pipe pile is used, and a rib is provided on the outer surface of the head. The support body 231 may be provided with a support base 232 at an upper portion thereof and capable of supporting a submerged tunnel.
The precedent foundation pile hole 233 is formed, for example, by an extracorporeal tube 501 or the like. The temporary receiving cross beam 502 is provided at the upper part, and the rubber packing 503 is provided at the lower part. The trailing foundation pile hole is formed by, for example, an outer tube 501, and a rubber packing 503 is provided at a lower portion. The rubber packing 503 includes the support 231 and the foundation pile 2.
When the concrete is poured between 33 and 234, the concrete is prevented from leaking.

<B> Construction of Sliding Bearing (Basic Structure of Underwater Tunnel) In a method of constructing the sliding bearing 230 in water, for example, first, the preliminary foundation pile 233 is driven. For that purpose, mooring a piled-in boat, adjusting the position, suspending the preliminary foundation pile 233,
Positioning is performed using an MN reader (extendable guide). The precedent foundation pile 233 is erected, driven into the water bottom with a vibratory hammer, and a hydraulic hammer with a yatco is attached to the precedent foundation pile 233 to perform submerged driving. When a predetermined number, for example, four, of the preceding foundation piles 233 is driven, the mooring of the pile driving boat is released. Next, in order to install the support 231, the crane ship is guided by the GPS to moor it, and the support 231 is
The position is guided by S, suspended through the suspension frame, and the support 231 is suspended down to about 2 m above the planned height. The reference pillar of the suspension frame is held by the MN leader,
It is set accurately so that 33 enters the precedent foundation pile hole 235 of the support 231. After installation, detach the suspension frame with the quick release joint. Thus, the precedent foundation pile 23
By inserting 3 into the precedent foundation pile hole 235 of the support, the precedent foundation pile 233 also has a function of positioning the support. Next, in order to drive the trailing foundation pile 234, the pile driving ship is moored, the position is adjusted, the trailing foundation pile 234 is suspended, and the support 231 is put into the trailing foundation pile hole 236. Then, a hydraulic hammer with a Yatco is attached to the following foundation pile 234 with a vibratory hammer, and the underwater casting is performed. When a predetermined number, for example, 12, of the trailing foundation piles 234 are driven, the mooring of the piled-in boat is released. In addition, concrete is cast into the steel shell of the support to build a sliding bearing.

Although the above description has been made of the case where a concave arc-shaped tunnel having a height difference is constructed, the case where the tunnel is constructed on the same horizontal plane is also conceivable. In these cases, when it is necessary to construct the bottom surface of the box production jar 310 and the extrusion yard 300 on a horizontal plane, water is provided at both front and rear ends of the extrusion jar 300 to perform extrusion. As an example, it can be considered that the water level in the yard can be adjusted.

[0029]

As described above, the underwater tunnel foundation of the present invention has the following effects. <B> Compared with a continuous support type foundation such as a submerged tunnel, crushed stone foundation and mortar foundation are not required. <B> There is no need to treat floating mud flowing into the trench during construction. <C> Since a foundation pile is used, there is no structural problem even if a gap is formed between the housing bottom and the ground. <D> Work on the sea is reduced, and the effect on the navigating ship is reduced.

[Brief description of the drawings]

Fig. 1 Explanatory drawing of the entire excavation work of a submarine tunnel

FIG. 2 is an explanatory view of an extrusion yard and a manufacturing yard.

FIG. 3 is an explanatory view of an extrusion device.

FIG. 4 is an explanatory view of an extrusion device.

FIG. 5 is an explanatory view of an extrusion device.

FIG. 6 is an explanatory diagram of an extrusion process.

FIG. 7 is an explanatory diagram of an extrusion process.

FIG. 8 is an explanatory diagram of an extrusion process.

FIG. 9 is an explanatory view of an extrusion process.

FIG. 10 is an explanatory diagram of an extrusion process.

FIG. 11 is a top view of a sliding bearing support.

FIG. 12 is a sectional view taken along the line XII-XII of FIG. 11;

FIG. 13 Layout diagram of precedent foundation pile

FIG. 14 Layout plan of the post foundation pile

Continued on the front page (72) Inventor Satoru Nagase 1-25-1, Nishishinjuku, Shinjuku-ku, Tokyo Taisei Corporation

Claims (2)

[Claims] 1. A substructure for an underwater tunnel, wherein a support is installed on a pile provided on the underwater floor, and a support base for supporting a box body of the underwater tunnel is installed on the support. 2. A positioning pile is provided on the bottom of the water, a support for supporting the box of the underwater tunnel is installed on the positioning pile, and the support is positioned. Thereafter, a post-pile is provided to support the support. The construction method of the foundation structure of the underwater tunnel.