JP4116381B2 - Shield tunnel and shield excavator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a shield tunnel with a low earth covering, which is constructed on the seabed or under a riverbed, and used as a road, for example, and a shield excavator for excavating the tunnel.
[0002]
[Prior art]
As a technique for creating a tunnel such as a road tunnel under the seabed or under the riverbed, there are conventionally a submerging method and a shield method.
[0003]
In the subsidence method, a seabed or a riverbed is dug down from the sea or the river, and a plurality of reinforced concrete boxes having a required cross section (mostly a rectangular cross section) are set therein. Next, this reinforced concrete box is backfilled with earth and sand and covered with chestnut.
[0004]
In this subsidence method, the tunnel is installed in a shallow place under the seabed or under the riverbed. Therefore, when the application is a road tunnel, the road alignment can be shortened compared to a shield tunnel.
[0005]
The shield method is advantageous in that it does not pollute sea areas and river areas and does not cause destruction of the ecosystem because tunnel construction work is performed underground.
[0006]
[Problems to be solved by the invention]
However, in the subsidence method, tunnels are excavated from the sea or river, so there is a risk of destroying the marine and river ecosystems due to contamination of seawater and river water.
[0007]
Moreover, since the rectangular cross section is often employed in the submerging method, it is necessary to increase the thickness of the member, and a large amount of materials such as reinforcing bars and concrete are used.
[0008]
Furthermore, if the tunnel has a circular cross-section in the subsidence method, it will excavate deeply under the seabed or under the riverbed, making it difficult to excavate from the sea or upstream, resulting in a longer construction period. Therefore, it is difficult to adopt a circular cross section that is advantageous against earth pressure and water pressure.
[0009]
On the other hand, when a circular cross section is adopted in the shield method, it is necessary to increase the depth of the ground compared to the submerged method in order to prevent the shield excavator and the lining segment from being lifted by buoyancy. For this reason, in the use as a road tunnel, the shield tunnel becomes deeper in road alignment than the submerged tunnel, and the total length of the tunnel becomes longer.
[0010]
Furthermore, the shield method requires a certain amount of earth covering to stabilize the face, and it is generally necessary to increase the earth covering as compared to the submerged tunnel. For this reason, road alignment becomes deep.
[0011]
Furthermore, in recent years, tunnels having a vertically-symmetrical section with a rectangular section or an elliptical section have been made by the shield method. Since such a shield tunnel is flatter than a circular cross section, the earth covering can be reduced. However, in order to counter buoyancy, it is necessary to refill the bottom of the road surface with soil or fill with concrete. As a result, the space of the tunnel becomes small, and it becomes difficult to secure an evacuation passage, an emergency vehicle passage, and the like.
[0012]
The present invention has been made in view of the above circumstances, and the object of the present invention is to take advantage of the shield method, and to be strong against water pressure, earth pressure and buoyancy, and to be used as a road tunnel. It is another object of the present invention to provide a shield tunnel with a low earth covering that can secure an evacuation passage and an emergency vehicle passage.
[0013]
Another object of the present invention is to provide a shield excavator capable of accurately excavating the shield tunnel.
[0014]
[Means for Solving the Problems]
To achieve the above object, an invention according to claim 1, formed in the road shield tunnel, to form the bottom of the tunnel substantially arcuate second large curvature, the upper arcuate small curvature, the parabolic The overall cross-sectional shape is an inverted horseshoe shape having a larger horizontal diameter than the vertical diameter, the left and right sides of the tunnel are formed in an arc shape having a larger curvature than the lower part, and a road bed 5 is formed at the lower part of the tunnel. A roadbed concrete 6 is formed thereon.
According to the second aspect of the present invention, in the road shield tunnel, the lower portion of the tunnel is formed in a substantially circular arc shape 17 having a large curvature, the upper portion is formed in a substantially flat shape 18, and the overall cross-sectional shape is a horizontally long semicircular shape. The roadbed 5 is formed in the lower part of the tunnel, and the roadbed 16 is formed on the roadbed 5.
According to a third aspect of the present invention, in the shield tunnel according to the first or second aspect, a passage space is formed in the road bed 5.
In the invention of claim 4, the lower part of the shield tube 21 is formed in a substantially circular arc shape 25 having a large curvature, the upper part is formed in a substantially arc shape 26 having a linear or small curvature, and a parabolic shape, and the left and right sides are lower than the lower part. The cutter head 35 is formed so as to have an arc shape with a large curvature, and the tunnel cross-section has a substantially reverse horseshoe shape or a substantially semicircular shape whose lateral diameter is larger than the longitudinal diameter. It is characterized in that it is connected to and driven by a rotational drive unit 27 arranged in an appropriate number with a required interval.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0016]
[Example 1]
FIG. 1 is a cross-sectional view showing a first embodiment of the shield tunnel of the present invention.
[0017]
Shield tunnel 1 of the first embodiment shown in FIG. 1, the lower portion of the tunnel cross section is formed in a substantially arcuate 2 large curvature, the upper is formed in a substantially arcuate third small curvature, the overall cross-sectional shape It has a reverse horseshoe shape with a horizontal diameter larger than the vertical diameter .
[0018]
The outer shell of the shield tunnel 1 is constructed by connecting segments 4 formed in a shape suitable for the lower and upper portions of the tunnel cross section in the circumferential direction and the axial direction of the tunnel.
[0019]
The road bed 5 in the shield tunnel 1 is formed by backfilling excavated earth and sand, landfilled sand made of solidified soil obtained by mixing excavated earth and solidification material such as cement, or fluidized soil.
[0020]
A roadbed concrete 6 is placed on the upper surface of the roadbed 5 via a connecting member 7 that reinforces the tunnel.
[0021]
Further, below the roadbed concrete 6, the center portion of the roadbed 5 is divided by a column wall 8 provided on both sides, and a girder 8 ′ provided above between the column walls 8 on both sides. An emergency vehicle passage is secured, and an evacuation passage floor 10 is formed below the evacuation passage 9.
[0022]
Further, a pavement 11 is laid on the upper surface of the roadbed concrete 6.
[0023]
A road 12 is secured above the pavement 11 in the shield tunnel 1.
[0024]
In FIG. 1, reference numeral 12 ′ indicates a vehicle construction limit, and reference numeral D indicates a soil covering between the water bottom and the top surface of the shield tunnel.
[0025]
Shield tunnel 1 shown in the first embodiment, the lower portion of the tunnel cross section because it is formed substantially arcuate 2 large curvature, it is possible to increase the strength against the earth pressure, water pressure. Moreover, the escape passage 9 and the emergency vehicle passage can be secured below the roadbed concrete 6. Furthermore, it is possible to stabilize the tunnel by refilling the earth and sand in the unnecessary portion in the lower part of the shield tunnel 1 to create the road bed 5, increasing the weight of the tunnel, countering the buoyancy applied to the tunnel. .
[0026]
Next, FIG. 2 is a diagram showing the longitudinal linear depth of the shield tunnel 1 according to the first embodiment of the present invention and the shield tunnel 19 having a circular cross section when the earth covering is the same. Corresponding members are indicated by the same reference numerals. FIG. 3 is a diagram showing a comparison between the longitudinal linear depth of both shield tunnels shown in FIG. 2 and the road extension of the approach portion of the tunnel.
[0027]
When the shield tunnel 1 of the first embodiment of the present invention and the shield tunnel 19 having a circular cross section, as shown in FIG. 2, when the earth covering D is the same, the shield tunnel 1 of the first embodiment of the present invention, With the shield tunnel 19 having a circular cross section, a difference H is generated in the longitudinal linear depth direction. Due to the difference H, a road extension difference 2L is generated in the approach portion of the tunnel. This road extension difference 2L is obtained by the following equation.
[Expression 1]
2L = 2H / sinΘ
Here, Θ is the road gradient from the ground to the tunnel approach.
[0028]
According to the shield tunnel 1 of the first embodiment of the present invention, the road extension can be shortened by 2 L compared to the shield tunnel 19 having a circular cross section. Therefore, equipment and materials for tunnel construction can be saved and the construction period can be shortened.
[0029]
Further, according to the shield tunnel 1 of the first embodiment, since tunnel construction work is performed in the ground, the advantage of the shield construction method that can eliminate pollution of the sea area and the river area can be utilized as it is.
[0030]
[Example 2 ]
FIG. 4 is a cross-sectional view showing a second embodiment of the shield tunnel of the present invention.
[0031]
Shield tunnel of Example 2 shown in FIG. 4, the lower portion of the tunnel cross section is formed in a substantially arcuate 17 large curvature, the upper is formed in a substantially planar 18, the overall cross-sectional shape substantially semicircular oblong I am doing.
[0032]
Further, the road bed 5 is formed by backfilling excavated earth and sand.
[0033]
In the shield tunnel of Example 2 , the upper part of the tunnel cross section is formed in a flat shape 18, but when the soil covering load is small, there is no problem in strength.
[0034]
The other configuration of the shield tunnel of the second embodiment is the same as that of the shield tunnel 1 of the first embodiment, and the operation is the same as that of the shield tunnel 1 of the first embodiment.
[0035]
Incidentally, the shield tunneling according to the present invention, the upper part of the shape of the tunnel section has been substantially arcuate third small curvature in Figure 1 may be a parabolic, or linearly as shown in FIG. 4 It is good if it is in these ranges.
[0036]
[Example 3 ]
Next, FIGS. 5 to 7 show an embodiment of a shield excavator for excavating a shield tunnel of Example 1 of the present invention, FIG 5 is a vertical sectional side view, FIG. 6 is a front view, FIG. 7 FIG.
[0037]
The shield excavator 20 of the embodiment shown in FIGS. 5 to 7 includes a shield tube 21, a partition wall 22, a hood portion 23, a tail portion 24, a rotary drive portion 27 for a cutter head, and a parallel crank motion mechanism 30. And a cutter head 35, a chamber 39 for excavating earth and sand, a soil removal device 40, a propulsion jack 43, and the like.
[0038]
And the shield tube 21, a partition wall 22, the hood portion 23, and the tail portion 24, the lower portion of the cross section perpendicular with respect to the axial direction of the shield excavator 1 is formed in a substantially arcuate 25 large curvature, upper small curvature Are formed in a substantially arc shape 26.
[0039]
As shown in FIG. 5 , the cutter head rotary drive unit 27 includes a drive motor 28 and a pinion 29 connected thereto.
[0040]
The parallel crank motion mechanism 30 for the cutter head includes an internal gear 31 meshed with the pinion 29, a rotating body 32 that is integrally formed with the internal gear 31 and is rotatably supported by the partition wall 22. It has an eccentric distance e with respect to the center of the rotating body 32 and an eccentric shaft 33 provided eccentrically.
[0041]
The rotary drive unit 27 and the parallel crank motion mechanism 30 are arranged in five sets in this embodiment at a required interval, and the five sets of rotary drive unit 27 and the parallel crank motion mechanism 30 are arranged. The cutter head 35 is configured to be able to perform a parallel crank movement in cooperation.
[0042]
A mud clay material inlet 34 is provided in the center of the rotating body 32 from the inside of the machine toward the chamber 39.
[0043]
The cutter head 35 has a cutter frame 36 and a number of cutter bits 37 implanted in the cutter frame 36. As can be seen from FIG. 4 , the cutter frame 36 is formed in an approximate shape to the shield tube 21, the partition wall 22, the hood portion 23, and the tail portion 24 .
[0044]
A plurality of stirring blades 38 are provided on the surface of the cutter frame 36 on the chamber 39 side.
[0045]
The chamber 39 is formed in a space surrounded by the partition wall 22, the hood portion 23, and the cutter head 35.
[0046]
In this embodiment, a screw conveyor is used for the earth removing device 40. The earth removing device 40 includes a drive unit 41 and an earth discharging port 42, and is installed with the inlet portion facing the chamber 39.
[0047]
A plurality of the propulsion jacks 43 are installed at predetermined intervals in the circumferential direction inside the shield tube 21.
[0048]
In the shield cylinder 20 in this embodiment, when a plurality of sets of rotary drive units 27 are driven simultaneously and in the same direction in the ground, parallel crank motion mechanisms 30 connected to the respective rotary drive units 27 are interlocked, The cutter head 35 performs a parallel crank motion by the pair of parallel crank motion mechanisms 30.
[0049]
As the cutter head 35 performs a parallel crank motion, the face is excavated by the cutter bit row 37, and the excavated soil is taken into the chamber 39.
[0050]
As described above, the excavated mud material is injected into the excavated soil taken into the chamber 39 from the mud clay material inlet 34, and the excavated mud material and the mud mud material are agitated by the stirring blades 38 provided in the cutter frame 36. The earth and sand having plastic fluidity is created.
[0051]
Then, the earth removal device 40 is driven along with the excavation, and the earth and sand in the chamber 39 is taken into the earth removal device 40 while preventing the face from collapsing, and is discharged to the rear of the shield excavator 20 through the earth discharge port 42. The
[0052]
Further, the segment 44 is assembled at the rear part in the shield excavator 20.
[0053]
As described above, the earth and sand in the chamber 39 is discharged and the segment 44 is assembled. Then, a plurality of propulsion jacks 43 are simultaneously extended, and the reaction force is applied to the segment 44 to propel the entire shield excavator 20.
[0054]
Next, each propulsion jack 43 is contracted, and the segment 44 is assembled at the rear part of the shield excavator 20 again.
[0055]
Repeat the above work to dig a shield tunnel.
[0056]
According to the shield excavator 20 described above, the shield tube 21, partition wall 22, the lower portion of the cross-section perpendicular with respect to the axial direction of the hood portion 23 and the tail portion 24 is formed in a substantially arcuate 25 large curvature, the small curvature of the top The cutter head 35 is formed in an approximate shape to the right-angle cross-sectional shape of the shield cylinder 21, the partition wall 22, the hood portion 23 and the tail portion 24, and the cutter head 35 is formed into a parallel crank motion mechanism 30. The shield tunnel 1 of the first embodiment shown in FIG. 1 can be excavated accurately.
[0057]
In the shield excavator for excavating the shield tunnel of Example 2 shown in FIG. 4 , the shield cylinder 21, the partition wall 22, the hood portion 23, and the tail portion 24 are each formed in a shape corresponding to the tunnel cross section to be excavated, The cutter head 35 is formed in a shape approximate to the tunnel cross section.
[0058]
【The invention's effect】
Or a shield tunneling of the present invention is described, since the formation of the lower tunnel section substantially arcuate 2, 1 7 of large curvature, there is an effect that can make a large strength against water pressure-earth pressure, in the tunnel It has the effect of embedding earth and sand underneath to increase the weight of the tunnel, counteracting the buoyancy applied to the tunnel, and stabilizing the tunnel. It has the effect capable of ensuring the vehicle traffic channel further tunnel section substantially arcuate 3 the upper small curvature, since the formed almost flat 18, in the case of road tunnels, the shield tunnel circular section Compared to this, there is an effect that can shorten the road extension, and in addition to saving equipment and materials for tunnel construction, there is also an effect that can shorten the construction period, tunnel construction work in the ground Is performed, being able to eliminate the pollution of waters and river area, also has the advantage to be taking advantage of as it is the effect of the shield method.
[0059]
Further, the shield tube 21 is a shield excavator of the present invention, the partition wall 22, the lower portion of the cross-section perpendicular with respect to the axial direction of the hood portion 23 and the tail portion 24, and formed in a substantially arcuate 25 large curvature, linear or upper substantially arcuate 26 small curvature, is formed in a parabolic shape, and the cutter head 35 the shield tube 21, partition wall 22, receptacle 23 and is formed in the approximate shape perpendicular cross-sectional shape of the tail portion 24, the cutter head 35 Since it is connected to the rotational drive unit 27 via the parallel crank motion mechanism 30, there is an effect that the shield tunnel according to the present invention can be excavated accurately.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of a shield tunnel of the present invention.
FIG. 2 is a view showing a comparison of longitudinal linear depths of a shield tunnel of Example 1 of the present invention and a shield tunnel having a circular cross section when the earth covering is the same.
FIG. 3 is a diagram showing a comparison between the longitudinal linear depth of both shield tunnels shown in FIG. 2 and the road extension of the approach portion of the tunnel.
FIG. 4 is a cross-sectional view showing a second embodiment of the shield tunnel of the present invention.
FIG. 5 is a longitudinal side view showing an embodiment of the shield excavator of the present invention.
FIG. 6 is a front view of the shield excavator.
FIG. 7 is a rear view of the shield excavator.
[Explanation of symbols]
1 Shield Tunnel 2 Tunnel substantially arcuate 3 substantially arcuate fourth segment 5 subgrade 6 subgrade concrete 7 connecting member 8 Hashirakabe 8 'spar 9 evacuation passage of small curvature at the top of the tunnel cross-section of the large curvature at the lower portion of the cross section in the lower planar 20 shield excavator 21 shield tube 22 partition wall 23 hood portion 24 tail portion 25 shield tube or the like in the upper portion of the substantially arc-shaped 18 tunnel cross section of the large curvature at the bottom of 12 the road D soil overburden 16 roadbed 17 tunnel section almost chamber 40 dumping device arcuate 27 rotary drive unit 30 parallel crank motion mechanism 35 the cutter head 39 excavated soil 43 propulsion jacks 44 segments of small curvature at the top, such as a substantially arcuate 26 shield tube of large curvature

Claims (4)

In the shield tunnel for roads, the lower part of the tunnel is formed in an almost arc shape (2 ) with a large curvature, and the upper part is formed in an arc shape with a small curvature, a parabolic shape
The overall cross-sectional shape is a reverse horseshoe shape whose horizontal diameter is larger than the vertical diameter,
The left and right sides of the tunnel are formed in an arc shape with a larger curvature than the lower part,
A roadbed (5) was formed at the bottom of the tunnel, and roadbed concrete (6) was formed on the roadbed (5).
Shield tunnel characterized by that. In shield tunnel for road,
The lower part of the tunnel is formed in a substantially circular arc shape (17) with a large curvature, the upper part is formed in a substantially flat shape (18), and the overall cross-sectional shape is a horizontally long semicircular shape,
A roadbed (5) was formed at the lower part of the tunnel, and a roadbed (16) was formed on the roadbed (5).
Shield tunnel characterized by that. The shield tunnel according to claim 1 or 2, wherein a passage space is formed in the road bed (5).
Shield tunnel characterized by that. The lower part of the shield tube (21) is formed in a substantially curved arc shape (25) with a large curvature,
The upper part is formed in a substantially arc shape (26) or parabola with a linear or small curvature,
Form the left and right arcs with a larger curvature than the bottom,
The cutter head (35) is formed so that the tunnel cross-section has a substantially reverse horseshoe shape or a semi-circular shape whose horizontal diameter is larger than the vertical diameter,
A shield excavator characterized in that the cutter head (35) is connected to and driven by a rotational drive unit (27) arranged in an appropriate number at a predetermined interval, which constitutes a parallel crank motion mechanism (30). .

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