JP3472953B2 - Tunnel digging device and tunnel digging method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel excavating device which enables excavation while grasping the condition of rock mass.

[0002]

2. Description of the Related Art A tunnel excavator called a TBM (tunnel boring machine) is suitable for excavating a hard rock with a self-supporting face at high speed. However, in bad rock, if the face collapses, it may be difficult to excavate. This is because the excavated face, crown, and side walls are collapsing, and the rock around the excavated cavity is deformed by ground pressure and tightens the fuselage. Before such a situation is reached, it is necessary to grasp the signs early on and take appropriate mechanical operations and rock reinforcement measures to avoid troubles that make it difficult to excavate. For this reason, conventionally, the TBM driver's intuition has been used to predict the state of the face, the crown, and the side wall. In order to investigate the geology in front of the face in more detail, methods such as seismic reflection method and advanced horizontal boring have been adopted.

[0003]

However, the above-mentioned conventional method is uneconomical because it is necessary to stop the tunnel excavation work. Apart from the above method, there is a research example of an attempt to judge the strength of rock mass using data such as torque, thrust, and excavation speed obtained from an excavator during excavation, but the range of application is good rock mass. Limited, in bad bedrock that does not stand alone, such as a face,
Proper assessment was difficult.

The present invention has been made in order to solve the above-mentioned conventional problems, and provides a tunnel excavation device capable of performing an optimum excavation work by utilizing data obtained during the excavation work. The purpose is to

[0005]

In order to achieve the above-mentioned object, the tunnel excavator of the present invention is a tunnel excavator for excavating in a rock mass, in which a cutter torque, a thrust, an excavation speed, and a cutter head rotation speed. A tunnel excavator equipped with a sensor that detects the power consumption of the cutter rotation motor, and a parameter related to torque and a parameter related to thrust are extracted from the detected values of each sensor and a display device that illustrates the correlation between both parameters is provided. It is characterized by.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the tunnel excavation device of the present invention will be described below with reference to the drawings.

<A> Installation of sensor. A tunnel excavator which is called a TBM for excavating in a rock is divided into a front body 1 and a rear body 2, which are connected by a jack 4 and which is provided with a cutter head 3 on the front surface. This excavator is equipped with a sensor that can detect the following numerical values. Cutter torque, thrust, excavation speed, cutter head rotation speed, power consumption of the cutter rotation motor.

<B> Relationship between strength and thrust in solid rock. Rock strength S. It is known that the following proportional relationship is recognized between the thrust F, the torque T, and the cut amount P. ("Resources and Materials" Vol12, N
o. 5, pp303-308, 1996)

S = a · F / P (1) S = b · T / P ^c (2) P = v / N (3) where v: excavation speed (eg, excavation length per minute). N: Number of rotations of the cutter head (for example, number of rotations per minute). a, b: proportional constants. c: Parameter. There is a research example with 1 and 1.5.

Further, the excavation volume specific energy is defined as the energy required to excavate a unit volume of rock mass. This has long been used as an index of excavation efficiency of excavating machines. This is considered to be directly proportional to the rock mass strength.

Further, it is known that most of excavation energy in TBM is energy for rotating the cutter head. For that purpose, the drilling volume specific energy E
s can be approximately calculated by the following equation. Es = W /
(VtπD ^2/4) where, W: the cutter head rotating motor power consumption. D: Excavation diameter. t: excavation time. Thus, the drilling volume specific energy is
It is a parameter related to the cutter head rotation torque.

<C> Relationship between strength and thrust in poor rock mass. T / P ^c (or Es) is adopted as a parameter related to torque, and F / P ^c (or Es) is adopted as a parameter related to thrust.
If P is adopted, both parameters will increase as the rock mass strength increases in a solid rock mass. However, previous studies have shown that this relationship does not always hold in a collapsing poor rock mass where the face and crown are not self-sustaining. The reason is that if the face collapses, the excavator will not be able to keep up with the fallen rock fragments. This causes the cutter head face plate to be pushed, and the cutter head rotation torque rises abnormally. (Fig. 3) Alternatively, even if the face is self-supporting, if the top of the rock collapses and the rock mass is added as the top load of the excavator, or the rock cavity is greatly deformed due to the ground pressure, and as a result the excavator is tightened, The friction between the excavator and the rock mass increases rapidly. Then, the thrust increases abnormally. (Figure 3)

<D> Application on defective rock mass. As described above, it is difficult to grasp the situation only by the torque and the thrust. Therefore, as shown in Fig. 4, let us show the relationship between the data distribution and the rock mass condition on the correlation diagram of both parameters. Then, it can be seen that when the bedrock is soft, that is, when the compressive strength is small, the data are collected in the lower left area of the figure, and when the bedrock is hard, that is, when the compressive strength is large, the data are collected in the upper right area of the figure. Therefore, when excavation is carried out smoothly, the data moves in the strip-shaped region (normal excavation region) from the lower left to the upper right of the figure according to the hardness of the bedrock.

On the other hand, when the face is collapsing or the slit is closed, the rate of increase of the cutter head rotation torque is larger than the increase of thrust. Then, the data deviates from the normal excavation region and moves to the lower right region of FIG.

On the other hand, when the top end collapses and a large load is applied to the excavator or the deformation of the wall surface due to ground pressure becomes large and the body of the excavator is tightened, the rate of increase in thrust compared to the increase in torque is increased. Grows larger. In this case, the data moves to the upper left area of FIG.

When both the face and the crown are severely collapsed, both thrust and torque increase. The data in this case moves to the upper right area of FIG. 4 and does not deviate from the normal excavation area.
However, in this case, it is possible to distinguish from the case where the rock is hard and normal excavation is performed from other information, such as visually observing the state of excavation deviation with a belt conveyor or the like.

In actual excavation, the absolute values of torque and thrust vary depending on the operation of the excavation speed of the excavator. However, based on the above equations (1) and (2), T / P ^c (or Es) is adopted as a parameter related to torque,
If F / P is adopted as a parameter related to thrust,
These effects can be offset.

<E> Feedback to excavation work. The excavating device of the present invention displays the correlation diagram as shown in FIG. 4 on a personal computer in real time. Then, from the distribution of the data on the figure and the movement trajectory thereof, the condition of the rock mass during the excavation is judged based on the relationship of FIG. In particular, it is possible to continue excavation under optimum conditions while accurately judging the condition of the bedrock currently being excavated. The device for displaying the correlation diagram as shown in FIG. 4 can be installed inside the excavator or outside the fuselage.

[0019]

INDUSTRIAL APPLICABILITY The tunnel excavator of the present invention is an excavator capable of detecting data such as thrust, cutter head rotation torque, and excavation speed currently being excavated and displaying the correlation diagram thereof in real time on a personal computer. Therefore, the following effects can be obtained. <a> It is possible to grasp and display changes in the rock condition during excavation in units of cm. Therefore, by operating according to the display, it is possible to continue the efficient excavation by selecting the optimum condition. <B> For example, when the rock face condition of the face has changed to collapse, the operator reduces the rotation speed of the cutter head,
By taking measures such as reducing the excavation speed, it is possible to continue excavation while avoiding the blockage of the cutter head's misalignment inlet. <C> Furthermore, by displaying a correlation diagram of average data for each stroke of the excavator (up to about 1 to 2 m until the propulsion jack is fully extended), the degree of collapse etc. can be grasped and sprayed concrete, steel frame It can be used to judge the selection of support work such as liners. For example, if there is no sign of recovery when the bedrock condition shifts to catchability, it is judged that the thrust may be insufficient with the main gripper alone,
It is a method to put a liner and take measures to remove the propulsive reaction force of the shield jack.

[Brief description of drawings]

FIG. 1 is an explanatory view of a situation of a tunnel excavating device when a face is collapsed.

FIG. 2 is an explanatory view of the situation of the tunnel excavating device when the top end is collapsed.

FIG. 3 is a correlation diagram of parameters related to torque and parameters related to thrust.

FIG. 4 is a correlation diagram for determining the condition of rock mass shown on the screen of a personal computer.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takuya Tani               1-25-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo               Naru Construction Co., Ltd.                (56) References JP-A-9-112185 (JP, A)                 JP-A-8-101191 (JP, A)                 JP-A-8-234831 (JP, A)                 JP-A-9-233700 (JP, A)

Claims (6)

(57) [Claims] 1. In a tunnel excavator for excavating in rock, a sensor for detecting cutter torque, thrust, excavation speed, cutter head rotation speed, and power consumption of a cutter rotation motor is installed, and torque is detected from the detected value of each sensor. A tunnel excavator equipped with a display device for extracting parameters related to thrust and parameters related to thrust and displaying data on a correlation diagram of both parameters . 2. The tunnel excavation device according to claim 1, wherein {torque / (cut amount to the c-th power)} is adopted as a parameter relating to torque . 3. The tunnel excavation device according to claim 1, wherein the amount of power consumption of the cutter rotation motor per unit excavation volume is adopted as the parameter relating to torque . 4. The tunnel excavating device according to claim 1, wherein (thrust / dividing amount) is adopted as a parameter relating to thrust . 5. The tunnel according to any one of claims 1 to 4.
Using a drilling rig, the movement trajectory of the data displayed on the display device
It is special to adjust the rotation speed and excavation speed of the rotary head.
How to excavate a tunnel. 6. The tunnel according to any one of claims 1 to 4.
Using the drilling rig, the flatness for each stroke of the excavator accumulated in the display device
Correlation diagram of average data shown Table, characterized in that the selection of shoring on the basis of the display results
How to excavate a tunnel.