JP2001280080A - Shield machine and shield excavating facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield machine capable of stabilizing a working face without obstructing the other work in a tunnel. SOLUTION: A sediment improving agent is injected into a pressure chamber 14 formed at the front of a shield body 11 by a bulkhead 13, and a screw type soil removing device 17 discharging the sediment in the pressure chamber to an atmospheric pressure chamber 16 side is provided in this soil pressure type shield machine 1. A soil removing pipe 42 having the length of ten times the inner diameter or above is connected to the discharge port 31a of the tubular casing 31 of the soil removing device 17, and the pressure at the outlet of the soil removing pipe 42 is set to the atmospheric pressure by the control of the rotating speed of a screw vane 33 provided in the tubular casing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth pressure shield excavator and a shield excavation equipment.

[0002]

2. Description of the Related Art Generally, in an earth pressure type shield machine, a soil improvement material is added and kneaded as needed to excavated earth and sand taken into a pressure chamber. It was conveyed to the rear side of the atmospheric pressure chamber, and was pressure-fed by a concrete pump from a work vehicle arranged behind the shield main body to a sediment transport device arranged further rearward through a pipe.

[0003] Conventionally, concrete pumps have
The two pistons for concrete extrusion are each operated alternately by a cylinder device, so that earth and sand are intermittently sent out.

[0004]

According to the above-mentioned conventional concrete pump, the pistons are alternately operated to suck the earth and sand in the earth removal device into the cylinder chamber. Pressure pulsates, causing the problem of unstable drilling,
Since a concrete pump having a relatively large volume is arranged below the discharge port of the earth removal device, there is also a problem that it interferes with other operations in a narrow tunnel.

Accordingly, an object of the present invention is to provide a shield excavator and a shield excavation facility which can stabilize a face and do not hinder other operations in a tunnel.

[0006]

According to a first aspect of the present invention, there is provided a shield machine comprising a pressure chamber formed in a front portion of a shield body by a partition wall. An earth-pressure shield excavator equipped with a screw-type discharge device that is filled and discharges the earth and sand in the pressure chamber to the atmospheric pressure chamber side, wherein a long end is provided at a rear end discharge port of the screw-type discharge device. Is connected to a discharge pipe made 10 times or more the inner diameter.

A shield machine according to a second aspect of the present invention is the shield machine according to the first aspect, wherein the rotation speed of the screw blades of the screw-type earthing device is controlled so as to reduce the speed at the outlet of the earth discharging pipe. The pressure is set to approximately the atmospheric pressure.

According to a third aspect of the present invention, a pressure chamber formed in a front portion of a shield body by a partition wall is filled with plasticized earth and sand, and the earth and sand in the pressure chamber is increased. An earth-pressure shield excavator provided with a screw-type discharging device for discharging to a pressure chamber side, wherein a discharging end whose length is at least 10 times the inner diameter is provided at a rear end discharge port of the screw-type discharging device. An earth pipe is connected, and pressure gauges are arranged at two places before and after the discharge pipe, and the measured values from these two pressure gauges are inputted to calculate the shear stress of the earth and sand based on a predetermined arithmetic expression. Part.

According to a fourth aspect of the present invention, there is provided a shield excavator, wherein a sediment improving agent is injected through a sediment improving material injection pipe into a pressure chamber formed by a partition at a front portion of the shield body. An earth-pressure shield excavator equipped with a screw-type earthing device for discharging earth and sand in the pressure chamber to the atmospheric pressure chamber side. An earth excavation pipe that is 10 times or more is connected, and a flow meter is provided in the middle of the above-mentioned soil improvement material injection pipe and the earth removal pipe. Is provided.

In the shield machine according to a fifth aspect of the present invention, a soil improving agent is injected through a soil improving material injection pipe into a pressure chamber formed by a partition wall at a front portion of the shield body. An earth-pressure shield excavator equipped with a screw-type earthing device for discharging earth and sand in the pressure chamber to the atmospheric pressure chamber side. Connecting a discharge pipe that is 10 times or more, and providing a flow meter and a density meter in the middle of the earth and sand improving material injection pipe and the discharge pipe, respectively, and inputting the measured values from these flow meters and the density meter, It is provided with a calculation unit for calculating the amount of dry sand actually excavated.

According to a sixth aspect of the present invention, there is provided a shield machine according to the present invention, wherein a screw-type conveying device is provided in the middle of an earth removal pipe of the shield machine. According to a seventh aspect of the present invention, there is provided a shield excavator according to the sixth aspect, wherein the screw excavator of the screw type excavator and the screw blade of the screw type conveyer are controlled by controlling the rotation speed of the screw excavator. The pressure at the outlet is approximately equal to the atmospheric pressure.

According to the configuration of each of the shield excavators described above, since the discharging pipe is directly connected to the screw type discharging apparatus,
For example, there is no need to provide a large-volume device such as a concrete pump at the exit of the earth removal device, so that it does not interfere with other operations in a narrow tunnel.
Also, no pulsation occurs.

In addition, by providing a flow meter and a density meter in the middle of the soil improvement material injection pipe and the earth removal pipe, the actual excavated soil amount of the ground or the actually excavated dry sand amount can be obtained. Therefore, it is possible to accurately know the state of the face of the ground.

Further, according to an eighth aspect of the present invention, there is provided a shield excavating machine according to any one of the first to seventh aspects, wherein the sediment discharged from the discharge pipe is transported outside the tunnel to the shield machine. A shield excavating equipment equipped with a kneading machine for kneading the earth and sand transporting device with the earth and sand discharged from an earth removal pipe and the earth and sand improving material supplied from an earth and sand improving material injection pipe; and a kneading machine using the kneading machine. And a pumping pipe for transporting the soil and soil to the outside of the tunnel by a pumping pump.

According to the construction of the shield excavating equipment, the earth and sand discharged from the outlet of the earth discharging pipe in the earth pressure type shield excavator and the pumping pipe for pumping the earth and sand to a predetermined place outside the tunnel are separated. Since the kneading machine for kneading the improving material is provided, it is possible to adjust the earth and sand properties suitable for the pumping, and therefore it is possible to efficiently pump the earth and sand out of the tunnel.

According to a ninth aspect of the present invention, there is provided a shield excavating machine according to any one of the first to seventh aspects, wherein the sediment discharged from the earth discharging pipe is transported outside the tunnel to the shield machine. A shield excavation equipment equipped with a device, wherein the earth and sand transport device is separated by a sieve device for separating solid matter such as gravel mixed in earth and sand discharged from an earth discharging pipe, and separated by the sieve device. A crushing device for crushing the solid material, and a kneader for guiding and kneading the fine-grained soil obtained by the sieving device and the crushed soil crushed by the crushing device, and the earth and sand kneaded by the kneader, And a pressure feed pipe for transporting outside the tunnel by a pressure feed pump.

According to the construction of the shield excavating equipment, the sieve is separated between the outlet of the earth discharging pipe in the earth pressure shield excavator and the kneader for kneading the earth improving material with the earth and sand. By installing a crushing device that crushes solids such as gravel, for example, when the drainage pipe is thickened, even if solids such as gravel are mixed in the soil, the earth and sand can be pumped out of the tunnel without any problem. Can be.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a shield excavation facility according to a first embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 1, this shield excavation equipment transports an earth pressure type shield excavator 1 propelled by pushing a segment S and earth and sand discharged from the shield excavator 1 to a predetermined location, for example, a shaft or the ground. And the earth and sand conveying device 2 for performing the operation.

The earth pressure shield excavator 1 has a cutter head 12 rotatably provided at a front portion of a shield body 11 and a partition wall 1 provided in the shield body 11.
Between the cutter head 3 and the cutter head 12, a pressure chamber 14 for taking in excavated earth and sand is formed.

The sediment improving material (also referred to as an additive) such as water, bentonite, or a polymer substance is injected into the partition 13 to plasticize the sediment taken in the pressure chamber 4. Injection device (hereinafter referred to as injection device) 15
Is connected, and a screw type discharging device (hereinafter, referred to as a discharging device) for discharging the earth and sand in the pressure chamber 14 to the atmospheric pressure chamber 16 side.
17 is connected. In addition, when the earth and sand itself is in a plasticized state due to the excavation of the cutter head, it is not necessary to inject the earth and sand improving material.
Reference numeral 18 denotes a head rotation driving device for rotating the cutter head 12 via a gear mechanism, 19 denotes a kneading device provided on the cutter head 12 side, and 20 denotes a pressure chamber provided on the partition 13. This is a pressure chamber pressure gauge that measures the pressure in the pressure chamber 14.

The injection device 15 is provided with a first soil improvement material storage tank (hereinafter referred to as a first soil improvement material storage tank) for adjusting and storing the soil improvement material.
A first storage tank 21 and a partition 13
And a first soil improvement material injection pipe (hereinafter, referred to as a first injection pipe) 22 for injecting the soil improvement material in the first storage tank 21 into the pressure chamber 14. A flow meter 23 and a density meter 24 are provided in the middle of the first injection pipe 22.

The discharging device 17 has a cylindrical casing 31 having one end connected to the partition wall 13 and the other end inclined obliquely upward and having a discharge port 31a formed at the other end. Opening / closing gate 32 for opening / closing exit 31a
And a screw blade 33 with a shaft rotatably disposed in the cylindrical casing 31, and an annular plate 34 provided near the rear end of the cylindrical casing 31 and attached to the outer periphery of the screw blade 33. And a rotation driving device 35 for discharging the earth and sand.

A discharge pipe 42 is connected to a discharge port 31a of the cylindrical casing 31 of the discharge device 17, that is, to the opening / closing gate 32 via a reducer 41. Is at least ten times as long as its inner diameter, and the other end extends to the earth and sand transport device 2. Further, a first pressure gauge 43 and a second pressure gauge 44 are provided at the upstream and downstream positions of the discharge pipe 42, and a flow meter 45 and a density meter 46 are provided.

The above-mentioned earth and sand transporting device 2 has a second earth and sand improving material storage tank (hereinafter, referred to as a second storage tank) for storing the earth and sand improving material.
51, the earth and sand discharged from the discharging pipe 42 and the second
A kneader 53 for kneading the soil improvement material injected from the second storage tank 51 via a soil improvement material injection pipe (hereinafter, referred to as a second injection pipe) 52, and a kneaded earth and sand kneaded by the kneader 53. For example, a pressure feed pipe 55 provided with a pressure feed pump 54 for feeding pressure to an earth discharging tank 56 provided on the ground. A flow meter 57 and a density meter 58 are provided in the middle of the second injection pipe 52.

In addition, the shield machine 1 controls the above-mentioned devices, inputs a measurement value from each measuring device, performs a predetermined calculation, and, based on the calculation result, determines a predetermined device, for example, a discharge device. A control operation device (not shown, but also an example of an operation unit) for controlling the rotation speed of the screw blade 33 of the earth device 17 is provided.

For example, in this control operation device, each pipe 2
Flow meter provided midway between 2, 42 (electromagnetic flow meter, specifically, speed is detected and flow rate is determined)
23 and 45 and the measurement values from the densitometers 24 and 46 are input to calculate the flow rate and mass of the soil improvement material injected into the earth discharging system, and to calculate the first and second parts provided in the earth discharging pipe 42. The measured value of the earth pressure by the pressure gauges 43 and 44 is inputted, and the shear stress τ of the earth and sand transferred in the earth discharging pipe 42 is obtained. In addition, the flow rate and the dry sand amount of the soil improvement material injected from the second storage tank 51 can be known by the flow meter 57 and the density meter 58 provided in the middle of the second injection pipe 52. Of course, the pressure gauge 20 provided on the partition wall 13 is also input to the control arithmetic unit and used for excavation management.

In the above configuration, the excavated earth and sand enters the pressure chamber 14 by the rotation of the cutter head 12, where it is kneaded with the soil improvement material, and is rotated obliquely rearward by the rotation of the screw blade 33 of the earth discharging device 17. Is transferred to the discharge port 31a having a predetermined height, and then to the earth and sand transporting device 2 disposed rearward by a predetermined distance via the discharge pipe 42.

At this time, the screw blade 3 of the discharging device 17
By controlling the rotation speed of 3, the pressure at the outlet of the discharge pipe 42 is controlled so as to be substantially equal to the atmospheric pressure, preferably, just equal to the atmospheric pressure.

Here, the principle of this control will be described. The pressure of the face, that is, the pressure at the inlet of the cylindrical casing 31 in the pressure chamber 14 is P ₀ , the pressure drop value generated in the earth removal device 17 is ΔP _s , and the cylindrical casing 3
The pressure difference (density pressure of earth and sand) based on the difference (height) between the inlet and the outlet of No. 1 is ΔP _h , and the pipe resistance is ΔP _p based on the pipe length of the discharging pipe 42. In the graph,
As shown in FIG. 2 (a) shows a schematic configuration of the earth discharging device, and FIG. 2 (b) shows the pressure at each position.

Hereinafter, the pressure generated in the earth discharging system will be described in more detail. Assuming that the pressure at the outlet of the discharge pipe 42 is P _L , the following equation (1) is established. P _L = P ₀ − (ΔP _s + ΔP _h + ΔP _p ) (1) In the expression (1); ΔP _s = (τ × L _s / D _b ) × U (2) ΔP _{h = γ × L s × sinφ ···} (3) ΔP p = (4τ / D p) × L p ··· (4) Further, tau is the shear stress, gamma is the density of soil, L _s is tubular casing , L _p is the length of the discharging pipe, D _b is the outer diameter of the screw blade, D _p is the inner diameter of the discharging pipe, φ is the inclination angle of the cylindrical casing, and U is the pressure drop number.

Here, the pressure drop number U will be briefly described. The present inventor has already derived the following equation (5) for obtaining a pressure drop value ΔP in a screw type soil discharging device in Japanese Patent Application Laid-Open No. 9-296691.

[0033]

(Equation 1) By modifying the above equation (5), the following equation (6) is obtained.

[0034]

(Equation 2) In the above equation (6), the part of (D _b / H) × bracket {...} Is the pressure drop number U shown in the following equation (7).

[0035]

(Equation 3) However, the symbols and subscripts used in the above formulas (5) to (7) are as follows.

P _LL : Pressure at an arbitrary position in the screw axial direction P ₀ : Inlet pressure of the cylindrical casing (earth pressure / water pressure in the pressure chamber) L: Length in the axial direction of the cylindrical casing H: Screw blade groove depth D: Screw blade diameter, tubular casing inside diameter C _1: coefficient _{[D b / (D b -H} )] C 2: factor _{[(D b -2H) / (} D b -H)] e: screw blade thickness t: screw Blade pitch α: Torsion angle of screw blade θ: Discharge angle of earth and sand γ: Density of earth and sand τ: Shear stress (generated between earth and sand, screw blade and casing) φ: Angle of inclination of cylindrical casing Meaning of each subscript above Is as follows.

[0037] b: screw diameter portion m: screw mean (center) diameter r: screw root diameter (diameter of the central axis) as described above, the pressure P _L just zero at the outlet of the exhaust drainpipe 42 The above-mentioned ΔP
_h and ΔP _p are values based on the inclination angle of the cylindrical casing 31 and the length and diameter of the discharge pipe, and therefore, the inlet pressure P ₀ of the cylindrical casing 31 in the pressure chamber 14, which is the pressure of the face, changes. when it is seen that may be adjusted [Delta] P _s.

For example, when P ₀ = 0.15 MPa, an appropriate earth removal amount is obtained as follows. However,
τ = 0.7 kPa, screw blade diameter D _b = 30 cm,
Screw pitch t = 0.8D _b , γ = 2g / cm ³ , L
_{Let s} / _Db = 5, _Lp / _Dp = 30, and .phi. = 25 degrees.

From equation (3), ΔP _h = 2 × 150 × si
n25 ≒ 12.7 kPa, and from equation (4), Δ
P _p = 4 × 0.7 × 30 = 84 kPa, and from equation (1), ΔP _s = 150− (84 + 12.7) = 53.3.
kPa.

By the way, ΔP _s = τ × 5 × U, so that U = 53.3 / (0.7 × 5) = 15.2. Here, the relationship between the pitch of the screw blades and the pressure drop number U with the discharge efficiency (the amount of excavated soil of the shield machine / the amount of discharge of the earth removal device) η as a parameter is as shown in the graph of FIG. From FIG. 3, η = 1.04 is obtained.

Accordingly, in this case, it can be seen that the amount of soil discharged from the earth discharging device should be 1 / 1.04 of the amount of soil excavated by the shield machine. That is, screw blade 3
The third rotation speed, is controlled so that this value, the pressure drop value [Delta] P _s commensurate with the inlet pressure P ₀ of the cylindrical casing of the pressure chamber 14 is obtained. The maximum value of the pressure drop value [Delta] P _s of dumping device is when the rotational speed of the screw vanes is zero. Further, in FIG. 1, the earth discharging pipe 42 is provided horizontally, but when the earth discharging pipe 42 is inclined, the same density pressure as in the equation (3) is considered.

As described above, the discharge pipe 42 having a length of 10 times or more the diameter (inner diameter) is connected to the discharge port of the cylindrical casing 31 of the screw type discharge apparatus 17 provided in the earth pressure type shield machine 1. With screw blade 33
Is controlled so that the pressure at the outlet of the discharge pipe 42 becomes equal to the atmospheric pressure, so that the sediment taken into the pressure chamber 14 and to which the soil improvement material is added is discharged.
And the earth and sand unloading device 2 through the discharge pipe 42 smoothly.
To the kneading machine 53 for further unloading.
After the soil improving material from the second storage tank 51 is injected and kneaded into the soil to have a predetermined property, the soil and sand are carried out from the pressure feed pipe 55 to the earth discharging tank 56 outside the tunnel.

When it is desired to know the properties of the earth and sand discharged from the earth discharging pipe 42, the measured values from the two pressure gauges 43 and 44 provided on the way are input to the control and arithmetic unit. By using the measured values, the shear stress can be obtained using an arithmetic expression.

For example, the two pressure gauges 4 in the discharge pipe 42
Pressure difference ΔP measured by 3 and 44, distance Δ between both measurement points
The relationship between L and the inner diameter D of the discharge pipe 42 and the shear stress τ is expressed by the following equation (8) using the above equation (4). Therefore, if the pressure difference ΔP is obtained, the shear stress τ is calculated as You can know. That is, since the properties of the earth and sand can be known, the injection amount of the earth and sand improving material can be controlled so as to obtain the optimum soil quality for discharge.

ΔP = (4τ / D) × ΔL (8) Also, the measured values from the flow meter 23 provided on the first injection pipe 22 and the flow meter 45 provided on the discharging pipe 42 are input to the control arithmetic unit, where the discharging pipe is used. It is possible to obtain the actual excavated earth and sand amount by obtaining the amount of earth excavated from the first injection pipe 22 and the injection amount of the soil improvement material injected into the pressure chamber 14 from the first injection pipe 22 and obtaining the difference between these. it can.

Further, the measured values from the flow meter 23 and the density meter 24 provided on the first injection pipe 22 and the flow meter 45 and the density meter 46 provided on the discharging pipe 42 are input to the control arithmetic unit. The amount of dry sand of the soil improvement material injected into the pressure chamber 14 from the first injection pipe 22 and the amount of dry sand of the earth and sand transferred through the discharge pipe 42 are obtained, and the difference between these is actually obtained. You can know the amount of excavated dry sand.

As described above, since the actual excavated soil amount of the ground and the amount of dry sand actually excavated can be obtained, the state of the face of the ground can be known with high accuracy. That is, excavation management can be performed accurately, which leads to safety management of construction.

In particular, the discharging pipe 42 is directly connected to the discharging apparatus 17.
As in the past, there is no need to provide a large volume device such as a concrete pump directly at the exit of the earth removal device, as in the past.Therefore, in narrow tunnels, for example, curving and segment assembly, etc. This does not hinder the operation and does not generate pulsation, so that the excavation operation can be performed stably.

In the first embodiment, the soil improving material has been described as being injected into the pressure chamber 14 and the kneader 53. However, if necessary, the earth discharging device 17 and / or
Alternatively, it is also injected into the discharge pipe 42. In this case, the downstream side of the density meter 24 of the first injection pipe 22 and the earth discharging device 17 and the earth discharging pipe 42 are connected via the branch injection pipes 22A and 22B. That is, the purpose is to detect the mass and the amount of dry sand of the soil improvement material injected into the earth discharging device 17 and the earth discharging pipe 42.

Next, an earth pressure shield machine according to a second embodiment of the present invention will be described with reference to FIG. In the embodiment described below, the earth and sand transport device in the shield excavation equipment described in the first embodiment is provided with a device for sorting solids such as cobblestones and gravel. Accordingly, a description will be given of a portion of the earth and sand transport device which is a main part of the configuration, and the same members as those in the first embodiment will be assigned the same reference numerals and description thereof will be omitted.

As shown in FIG. 4, the earth-pressure shield excavator 1 according to the second embodiment increases the diameter of the discharge pipe 42 of the shield excavator according to the first embodiment, Rotary sieving apparatus 6 having a rotary drum 61 having a mesh capable of passing a predetermined particle size before
2 and a crushing device (for example, a jaw crusher) 63 for crushing a solid having a particle size equal to or more than a predetermined particle size discharged from the sieving device 62 to a size smaller than the predetermined particle size.

Therefore, according to this configuration, the discharge pipe 4
If the diameter of 2 is increased, relatively large solids such as boulders and gravel may be transported,
When such solid matter is discharged from the discharge pipe 42, first, fine sediment smaller than a predetermined particle diameter falls in the sieving device 62 and directly falls into the kneading machine 53, but the solid matter remaining in the sieving device 62 is removed. The material is guided to the crushing device 63, where it is finely crushed and enters the kneader 53.

Therefore, the earth and sand that has come out of the discharging pipe 42 is
All of them can be conveyed to the outside of the tunnel, for example, to the earth discharging tank 56 via the pressure feeding pipe 55 without any trouble. Next, a shield excavation facility according to a third embodiment of the present invention will be described with reference to FIG.

The shield excavating equipment according to the third embodiment further provides a conveying force to the earth and sand during the discharge pipe of the earth-pressure shield excavator described in the first or second embodiment, thereby providing pressure. Therefore, this portion will be described, and the same members as those in the above embodiments will be assigned the same reference numerals and description thereof will be omitted.

That is, as shown in FIG. 5, the earth pressure type shield machine 1 according to the third embodiment includes a screw type transport device ( (Also referred to as a screw conveyor) 71.

The screw-type transfer device 71 has a cylindrical casing 72 having both ends connected to a front discharge pipe 42a and a rear discharge pipe 42b, and a central shaft rotatably disposed in the cylindrical casing 72. A transport for rotating the ribbon-shaped screw blade 73 via an annular screw blade 73 that is not provided and an annular plate 74 provided at a position near the rear end of the cylindrical casing 73 and provided on the outer periphery of the ribbon-shaped screw blade 73 And a rotation driving device 75.

According to this configuration, in addition to the operation and effect of the screw-type discharging device 17 in each of the above-described embodiments, when the discharging pipe 42 is long and the pressure drop due to the resistance in the pipe is large, the screw-type transfer device is used. Pressure is applied to the earth and sand in the casing by the ribbon-shaped screw blade 73 of 71, and the pressure is controlled to be substantially zero at the outlet portion of the discharge pipe 42.

As described above, by controlling the rotation speeds of the screw blades 33 and 73 in the screw-type discharging device 17 and the screw-type transporting device 71, for example, even when the discharging tube 42 is long, the discharge at the outlet of the discharging tube 42 is possible. The pressure can be approximately at atmospheric pressure. Of course, depending on the situation, it is also possible to control the screw blade of either the screw type discharging device 17 or the screw type conveying device 71. In addition, the screw-type transfer device 7
The functions and effects other than the pressure control by No. 1 are the same as those of the above-described embodiments.

Further, in the first to third embodiments, the screw blade 3 of the screw type discharging device 17 is used.
Although the one with a shaft is shown as 3, a ribbon-shaped screw blade without a central axis, such as the screw blade 73 of the screw-type transfer device 71 described in the third embodiment, may be used.

Hereinafter, a case where the ribbon-shaped screw blade is used will be described. It should be noted that the difference from the above embodiments is basically whether or not the screw blade has a shaft. Therefore, when the screw blades are the same as the members of the above embodiments, the same numbers are assigned. The description is omitted.

That is, as shown in FIG.
A ribbon-shaped screw blade 33 'having no center axis is rotatably arranged in a cylindrical casing 31 of 7', and a reducer 4 is provided at an outlet 31a of the cylindrical casing 31.
Diameter (inner diameter) of earth discharging pipe 42 'connected via 1'
Is sized to transport solids such as gravel and boulders by the ribbon-shaped screw blades 33 '.

Then, the inner diameter of the screw blade with a shaft is made larger than that of the discharging pipe connected in the case of a screw blade with a shaft. More specifically, the diameter is set to about 2/3 of the outer diameter of the screw blade 33 '.

Of course, this ribbon-shaped screw blade 17 '
Is also rotated by a rotary driving device 35 for discharging earth and sand through an annular plate 34 attached to the outer periphery thereof. In the first embodiment, the pressure drop value ΔP and the pressure drop number U shown in the equations (6) and (7) are the shear stress caused by the earth and sand filling the hole at the center of the ribbon-shaped screw blade. Since τ does not act, the following equation (9) and (1)
It is expressed as in equation (0).

[0064]

(Equation 4) FIG. 7 shows the relationship between the screw blade pitch and the pressure drop number U in which the discharge efficiency η is a parameter in this case.

In the region where the pressure drop number U is negative, the pressure drop value ΔP becomes negative, and the screw-type earth discharging device rather exerts the function of increasing the pressure and functions as a pump.
Therefore, since the pressure drop value changes depending on the selection of η, it is possible to cope with a change in the earth and sand in the pressure chamber of the shield main body, and at the same time, the resistance at the time of earth and sand transport in the earth discharging pipe 42 ′ becomes too large. If it is not possible to discharge only by the earth pressure, the pump may be operated by the ribbon-shaped screw blade 33 'and pushed out by the ribbon-shaped screw blade 33'. That is, the pressure can be reduced or increased by driving the ribbon-shaped screw blade 33 '.

When a ribbon-shaped screw blade is used, solids such as large gravel and boulders can be discharged as compared with the case of a screw blade with a shaft. For example, the discharge pipe 42 'is clogged. In order to cope with such a case, as shown in FIG. 8, it is formed in an arbitrary direction (the lower part in the drawing) before the outlet 31a at the rear end of the cylindrical casing 31 at a location different from the outlet 31a. A spare discharge pipe 81 may be connected to another discharge port 31b, and a spare gate 82 may be provided at this discharge port 31b. In this case, one of the gates 32 and 82 is opened. Of course, such a preliminary discharge pipe 81 can also be provided in the screw-type discharge apparatus 17 described in the first to third embodiments.

In each of the above embodiments,
Although only one pressure pump is provided in the pressure feed pipe in the earth and sand transfer device, a plurality of pressure pumps may be arranged in the middle according to the transfer distance.

Further, in each of the above-described embodiments, the present invention is applied to the shield method in which the segment S is pushed by pushing. However, the present invention can be applied to, for example, an extruded pipe type shield method instead of the segment.

[0069]

As described above, according to the construction of the shield machine according to the present invention, since the discharging pipe is directly connected to the screw-type discharging apparatus, it is necessary to connect the discharging pipe directly to the outlet of the discharging apparatus as in the prior art. There is no need to install large-volume equipment such as concrete pumps, so in a narrow tunnel, it does not interfere with other work and there is no pulsation,
Excavation work can be performed stably.

Also, by providing a flow meter and a density meter in the middle of the soil improvement material injection pipe and the earth removal pipe, the actual excavated soil amount of the ground or the actually excavated dry sand amount can be obtained. Therefore, it is possible to accurately know the state of the face of the ground. That is, excavation management can be performed accurately.

Further, according to the construction of the shield excavating equipment of the present invention, the earth and sand discharged from the outlet of the earth discharging pipe in the earth pressure type shield excavator is discharged between the pumping pipe for pumping to a predetermined place outside the tunnel. Since the kneading machine for kneading the earth and sand and the soil improving material is provided, it is possible to adjust the earth and sand properties suitable for the pumping, and thus to efficiently pump the earth and sand out of the tunnel.

Further, according to another construction of the shield excavating equipment of the present invention, a sieving device and a sieve are provided between an outlet of an earth removal pipe in an earth pressure type shield excavator and a kneader for kneading earth and sand with a soil improving material. By providing a crushing device that crushes solids such as gravel separated by a sieving device, for example, when the drainage pipe is thickened, even if solids such as gravel are mixed in Can be pumped out of the tunnel.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a schematic configuration of an earth pressure type shield machine according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a state of earth pressure in an earth removal device of the shield machine.

FIG. 3 is a graph showing a relationship between a pitch of a screw blade and a pressure drop number in the earth discharging device.

FIG. 4 is a sectional view showing a schematic configuration of an earth pressure shield machine according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing a schematic configuration of an earth pressure shield machine according to a third embodiment of the present invention.

FIG. 6 is a sectional view illustrating a schematic configuration of an earth pressure shield machine according to a fourth embodiment of the present invention.

FIG. 7 is a graph showing the relationship between the pitch of screw blades and the number of pressure drops in the earth removal device of the shield machine.

FIG. 8 is a cutaway side view of a main part of the earth discharging device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 earth pressure shield excavator 2 earth and sand transport device 11 shield body 13 partition wall 14 pressure chamber 15 earth and sand improving material injection device 17 screw type earth discharging device 17 ′ screw type earth discharging device 22 first earth and sand improving material injection pipe 23 flow meter 24 density Total 31 Cylindrical casing 31a Discharge port 33 Screw blade 33 'Ribbon screw blade 42 Discharge pipe 42' Discharge pipe 43 First pressure gauge 44 Second pressure gauge 45 Flow meter 46 Density meter 51 Second soil improvement material storage tank 52 No. 2 Soil improving material injection pipe 53 Kneading machine 54 Pumping pipe 57 Flow meter 58 Density meter 62 Sieve device 63 Crushing device 71 Screw-type transfer device 72 Tubular casing 73 Ribbon screw blade

Claims (9)

[Claims] A pressure chamber formed at a front portion of a shield body by a partition is filled with plasticized earth and sand.
An earth-pressure shield excavator equipped with a screw-type earthing device for discharging earth and sand in the pressure chamber to the atmospheric pressure chamber side, wherein a length of the screw-type earthing device at the rear end of the screw-type earthing device is A shield excavator to which an earthen pipe made ten times or more is connected. 2. The shield excavating device according to claim 1, wherein the pressure at the outlet of the discharge pipe is set to substantially the atmospheric pressure by controlling the rotation speed of the screw blade of the screw type discharge device. Machine. 3. A plasticized earth and sand is filled in a pressure chamber formed in a front part of a shield main body by a partition.
An earth-pressure shield excavator equipped with a screw-type earthing device for discharging earth and sand in the pressure chamber to the atmospheric pressure chamber side, wherein a length of the screw-type earthing device at the rear end of the screw-type earthing device is Connect the drain pipe made 10 times or more, and place pressure gauges at two places before and after the drain pipe, input the measured values from both pressure gauges, and based on a predetermined arithmetic expression, A shield machine comprising a calculation unit for calculating shear stress of earth and sand. 4. A soil improving agent is injected into a pressure chamber formed by a partition wall at a front portion of a shield body through a soil improving material injection pipe, and the earth and sand in the pressure chamber is discharged to an atmospheric pressure chamber side. An earth-pressure shield excavator equipped with a screw-type earthing device, wherein a length of the earthing pipe is at least 10 times the inner diameter of the screw-type earthing device at a rear end outlet thereof, and A flow meter is provided in the middle of the soil improvement material injection pipe and the discharge pipe, and a calculation unit for inputting a measured value from the flow meter and calculating an actual excavated amount of excavated soil is provided. Shield machine. 5. A sediment improving agent is injected into a pressure chamber formed by a partition wall at a front portion of a shield main body through a sediment improving material injection pipe, and sediment in the pressure chamber is discharged to an atmospheric pressure chamber side. An earth-pressure shield excavator equipped with a screw-type earthing device, wherein a length of the earthing pipe is at least 10 times the inner diameter of the screw-type earthing device at a rear end outlet thereof, and A calculation unit that installs a flow meter and a density meter in the middle of the soil improvement material injection pipe and the earth removal pipe, respectively, and inputs the measured values from these flow meters and the density meter to calculate the amount of dry sand actually excavated. A shield machine equipped with: 6. The shield machine according to claim 1, further comprising a screw-type transfer device provided in the middle of the discharge pipe. 7. The pressure at the outlet of the discharge pipe is set to approximately atmospheric pressure by controlling the rotation speed of the screw blades of the screw-type discharge device and the screw blades of the screw-type transfer device. A shield machine according to claim 6. 8. A shield excavation equipment comprising the shield machine according to any one of claims 1 to 7, further comprising a sediment transporting device for transporting earth and sand discharged from an earth discharging pipe to outside the tunnel. A kneading machine that kneads the earth and sand discharged from the earth discharging pipe and the earth and sand improving material supplied from the earth and sand improving material injection pipe, and conveys the earth and sand kneaded by the kneading machine out of the tunnel by a pressure pump. A shield excavation facility, comprising: 9. A shield excavation equipment comprising the shield machine according to claim 1, further comprising a sediment transporting device for transporting earth and sand discharged from an earth discharging pipe to outside the tunnel. A sifter for separating solids such as gravel mixed in earth and sand discharged from an earth removal pipe, a crushing device for crushing the solids separated by the sieving device, and A kneader for guiding and kneading the fine-grained soil obtained by the device and the crushed soil crushed by the crusher, and a pressure pipe for conveying the earth and sand kneaded by the kneader to the outside of the tunnel by a pressure pump. And a shield excavation facility comprising: