JP7790965B2 - Jack pattern selection support method and selection support device - Google Patents

Description

The present invention relates to a method and device for supporting the selection of jack patterns for shield jacks used to propel shield tunneling machines.

Traditionally, shield tunneling machines are used in tunnel excavation work using the shield method. Shield tunneling machines are equipped with shield jacks to drive the machine forward. Multiple shield jacks are usually placed at intervals around the periphery of the machine behind it. The operator controls the excavation direction of the shield tunneling machine by selecting whether or not to use each shield jack.

Controlling the excavation direction of a shield machine to align with the tunnel plan line requires skill and is difficult. To solve this problem, the present patent applicant has already proposed a machine learning model, described in Patent Document 1, for estimating the position of the force point of the shield jack, which determines the excavation direction of the shield machine. Figure 4 shows an example of the recommended force point position recommended by AI such as this machine learning model, and the calculated target force point position of the current thrust resultant force, displayed on the operator's operation screen. As shown in this figure, the operator checks the positions of the recommended force point and target force point, and selects the shield jack to use so that it matches the target force point. This allows for appropriate control of the shield machine's thrust direction.

On the other hand, the technology described in Patent Document 2 is known as a conventional technology related to supporting the selection of shield jack patterns.

JP 2019-143385 A Japanese Patent Application Laid-Open No. 2021-042584

However, when the conventional method of Patent Document 1 is applied, the following problems arise.
First, it is difficult for the operator to determine which shield jack to set from among the many shield jacks in order to match the position of the recommended force point, and this may place a burden on the operator.

Furthermore, if all possible combinations of N shield jacks (N is an integer of 2 or more, usually several tens) installed in a shield tunneling machine are searched, the number of searches becomes a huge number, ^2N , and it is necessary to calculate ^2N possible jack patterns. For this reason, it is difficult to select a jack pattern in a realistic amount of time.

There is also a risk that the operator will select an inappropriate jacking pattern in order to match the displayed target force point. Figure 5 is a schematic diagram of jacking patterns, with shield jacks used for excavation indicated by black circles and shield jacks not used indicated by white circles. For example, a jacking pattern like Figure 5(a) may cause the stress generated by the shield jack to concentrate at the bottom, potentially damaging the segment (inappropriate jacking pattern). On the other hand, a jacking pattern like Figure 5(b) does not concentrate stress in one area (appropriate jacking pattern). Therefore, it is desirable to select a jacking pattern like Figure 5(b) rather than Figure 5(a).

The present invention was made in consideration of the above, and aims to provide a jack pattern selection support method and selection support device that can present appropriate jack patterns in a short amount of time.

To solve the above-mentioned problems and achieve the objectives, the present invention provides a method for assisting in the selection of a jack pattern that determines the operating state of each of multiple jacks provided to propel a shield tunneling machine in the excavation direction. The method outputs a jack pattern that minimizes the difference in position between the force point of the resultant thrust force and a preset recommended force point, based on the contribution of each jack to the force point of the resultant thrust force of the jacks.

The jack pattern selection support device of the present invention is a device that supports the selection of a jack pattern that defines the operating state of each of multiple jacks provided to propel a shield tunneling machine in the excavation direction, and is characterized by outputting a jack pattern that reduces the difference in position between the force point of the resultant thrust force and a preset recommended force point based on the contribution of each jack to the force point of the resultant thrust force of the jacks.

The jack pattern selection support method of the present invention supports the selection of a jack pattern that defines the operating state of each of multiple jacks installed to propel a shield machine in the excavation direction. It outputs a jack pattern that minimizes the difference in position between the force point of the resultant thrust force and a preset recommended force point based on the contribution of each jack to the force point of the resultant thrust force of the jacks. This effectively enables the operator to quickly select an appropriate jack pattern.

Furthermore, the jack pattern selection support device of the present invention is a device that supports the selection of a jack pattern that determines the operating state of each of multiple jacks provided to propel a shield tunneling machine in the excavation direction. It outputs a jack pattern that minimizes the difference in position between the force point of the resultant thrust force and a preset recommended force point based on the contribution of each jack to the force point of the resultant thrust force of the jacks, thereby achieving the effect of being able to present an appropriate jack pattern to the operator in a short amount of time.

FIG. 1 is an explanatory diagram of a jack pattern selection support method and selection support device according to the present invention. FIG. 2 is a diagram showing an example of jack arrangement. FIG. 3 is a flow chart showing an embodiment of a jack pattern selection support method and selection support device according to the present invention. FIG. 4 is a diagram showing an example of a conventional screen display of recommended emphasis points. FIG. 5 shows an example of a conventional jacking pattern, where (a) is an inappropriate jacking pattern and (b) is an appropriate jacking pattern.

Below, an embodiment of the jack pattern selection support method and selection support device according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to these embodiments.

This invention supports the selection of a jack pattern that defines the operating state of each of multiple shield jacks installed to propel a shield tunneling machine in the excavation direction. The invention takes into account the contribution of each jack's resultant thrust force to the force point, and outputs, with a small number of searches, a jack pattern that minimizes the absolute deviation between the position of the resultant thrust force force point and the position of the recommended force point (for example, an AI-predicted force point predicted by AI, etc.).

(Basic principle of the present invention)
First, the basic principle of the present invention will be explained.
It is assumed that 12 shield jacks are arranged symmetrically and at equal intervals along the inner circumference of the rear side of the cylindrical shield that makes up the shield tunneling machine. When each shield jack is turned on, it receives a reaction force from the existing segment behind it and extends, propelling the shield tunneling machine forward. The on/off state of each shield jack can be switched by the operator or by operating a control device.

Figure 1 (1) shows the jack pattern in a coordinate plane diagram. As shown in this diagram, the horizontal line passing through the shield machine center point O is taken as axis _eH , and the vertical line pointing downward is taken as axis _eV . The jacks are placed at equal intervals on the circumference of a unit circle of radius 1 centered at the shield machine center point O.

The AI predicted force point (recommended force point) predicted by the AI etc. is defined as force point 1, the line connecting force point 1 and the shield tunneling machine center point O is defined as the axis of symmetry _eM , and the axis perpendicular to the axis of symmetry _eM is defined as the axis of symmetry _eN . The four sections divided by the axes of symmetry _eM and _eN will be called the first quadrant, second quadrant, third quadrant, and fourth quadrant, in counterclockwise order from the top.

Considering the contribution of each jack to the force point of the resultant thrust force, the on/off states of the jacks in the first and second quadrants and the jacks in the third and fourth quadrants are symmetrical with respect to the axis of symmetry _eM . The entire jack pattern can be searched using the group of jacks in the first and second quadrants or the group of jacks in the third and fourth quadrants. Thinking in this way, it is possible to reduce the number of jack pattern searches from ^2N to ^2N/2 .

Furthermore, with respect to the axis of symmetry _eN , the contribution of the resultant propulsion force to the force point of the jacks at symmetrical positions that are in the on state in the first and second quadrants and the third and fourth quadrants is canceled out, so it is possible to reduce the number of jack patterns to be searched from ^2N/2 to ^2N/4 .

By applying this invention, it is possible to select a jack pattern such as that shown in Figure 1 (1). It is also possible to select a jack pattern such as that shown in Figure 1 (2), in which the combination of jacks in the on/off state is different from that shown in (1). However, the position of force point 1 in Figure 1 (1) is the same as the position of force point 2 in (2). Furthermore, from the perspective of preventing a jack pattern such as a one-sided pushing state from being output, it is desirable to select a jack pattern such as that shown in Figure 1 (2), in which the minimum number of jacks used is guaranteed to be N/2 or more.

As shown in Figure 2(1), because the jacks are placed discretely in the circumferential direction, it is desirable to place the axis of symmetry _eM , which connects the recommended force point M and the shield machine center point O, so that it passes through the actual jack position or the midpoint between two adjacent jacks. To achieve this, for example, the central angle _θM (the angle it forms with the axis _eV ) of the axis of symmetry _eM may be fine-tuned for two separate cases, as shown in Figures 2(2) and 2(3). Then, a jacking pattern may be output that reduces the absolute value of the difference between the position of the force point of the thrust resultant force and the position of the recommended force point M.

In FIG. 2, _θi is the arrangement angle of each jack, where i = 1, ..., N (total number of jacks). Δθ is the difference in arrangement angle between jacks adjacent in the circumferential direction. Axis _e'M is the axis of symmetry _eM after fine adjustment. The central angle _θM and the jack arrangement angle _θi can be set, for example, with the positive direction of axis _eV (vertically downward) as the starting line (0°) and clockwise as the positive direction.

(Embodiment)
Next, an embodiment of a method for supporting selection of a jack pattern according to the present invention will be described.
As shown in Figures 3 and 2(1), first, a line is drawn between the recommended force point M placed on the coordinate plane and the shield machine center point O to create a symmetry axis _eM (step S1). Here, the recommended force point M is assumed to be set in advance. The recommended force point M may be a force point estimated using the machine learning model described in Patent Document 1 above, for example, or a force point set by another method.

Next, the central angle θ _M of the axis of symmetry e _M from the axis e _V is calculated (step S2), for example, with clockwise as the positive direction, and the arrangement angle θ _i of each jack is compared with the central angle θ _M of the axis of symmetry e _M (step S3).

Next, it is determined whether the inequality |θ _M - θ _i |≧Δθ/4 is satisfied (step S4). If the inequality is satisfied (Yes in step S4), the process proceeds to step S5. On the other hand, if the inequality is not satisfied (No in step S4), the process proceeds to step S7.

In step S5, it is determined that no jacks are positioned on the axis of symmetry _eM , and as shown in Figure 2 (2), the axis of symmetry _eM is finely adjusted so that it passes through the midpoint between the positions of jack number i and number i+1 (step S6). The axis of symmetry after fine adjustment is designated as axis _e'M .

On the other hand, in step S7, it is determined that the jack is positioned on the axis of symmetry _eM , and as shown in Figure 2 (3), the axis of symmetry _eM is finely adjusted so that it passes through the position of jack number i (step S8). The axis of symmetry after fine adjustment is designated as axis _e'M .

Next, after fine-tuning in step S6 (or step S8) above, the contribution Δe of the resultant thrust force per jack to the force point e is calculated from the number of jacks, N/4. The contribution Δe can be calculated, for example, by Δe = cos(θ _i )/N. Then, taking this contribution Δe into consideration, a jacking pattern is calculated that minimizes (min) the distance |e-M| between the force point e of the resultant thrust force and the recommended force point M (step S9). The calculation results are displayed on the operator's screen. The operator can look at this display and select the optimal jacking pattern for propelling the shield machine in the specified planned direction.

Finally, it is determined whether or not to end the jack pattern selection (step S10). If it is determined that it is to end (Yes in step S10), the process ends. On the other hand, if it is determined that it is not to end (No in step S10), the process returns to step S1 and repeats steps S1 to S9.

According to this embodiment, a jacking pattern is output that minimizes the difference in position between the force point of the resultant thrust force of all jacks and a preset recommended force point, based on the contribution of each jack to the force point of the resultant thrust force of all jacks. In other words, the force point to be selected can be converted into a jacking pattern and presented to the operator. Furthermore, by reducing the number of jacking pattern searches from a total of ^2N to ^2N/4 , an appropriate jacking pattern can be presented in a short time. This makes it possible to select a jacking pattern in a realistic time. Furthermore, the minimum number of jacks used is guaranteed to be N/2 or more, preventing the output of a jacking pattern that results in a one-sided pushing state.

In this way, this embodiment takes into account the contribution of each jack to the force point of the resultant thrust force, making it possible to select a highly reliable jack pattern and control the excavation direction of the shield machine with increased accuracy and stable precision.

Next, an embodiment of a jack pattern selection support device according to the present invention will be described.
The jack pattern selection support device according to this embodiment is a device that embodies the above-described jack pattern selection support method, and is composed of, for example, an input unit, an output unit, and a calculation unit. The input unit inputs the positional relationship between the recommended force point and the center point of the shield machine, the number of jacks, the jack placement angle, etc. The output unit outputs jack patterns such as those shown in Figures 1 (1) and 1 (2) on a display screen in the operator's room, etc. The calculation unit performs each of the processes in steps S1 to S10 above.

The input unit, output unit, and calculation unit can be configured using hardware such as a computer with a CPU, memory, and a display, as well as software such as a computer program that runs on this hardware.

According to this embodiment, a jacking pattern is output that minimizes the difference in position between the force point of the resultant thrust force of all jacks and a preset recommended force point, based on the contribution of each jack to the force point of the resultant thrust force of all jacks. In other words, the force point to be selected can be converted into a jacking pattern and presented to the operator. Furthermore, by reducing the number of jacking pattern searches from a total of ^2N to ^2N/4 , an appropriate jacking pattern can be presented in a short time. This makes it possible to select a jacking pattern in a realistic time. Furthermore, the minimum number of jacks used is guaranteed to be N/2 or more, preventing the output of a jacking pattern that results in a one-sided pushing state.

As described above, the jack pattern selection support method of the present invention supports the selection of a jack pattern that defines the operating state of each of multiple jacks provided to propel a shield tunneling machine in the excavation direction. Based on the contribution of each jack to the force point of the resultant thrust force of the jacks, the method outputs a jack pattern that minimizes the difference in position between the force point of the resultant thrust force and a preset recommended force point. This allows the operator to quickly find an appropriate jack pattern.

Furthermore, the jack pattern selection support device of the present invention is a device that supports the selection of a jack pattern that determines the operating state of each of multiple jacks provided to propel a shield tunneling machine in the excavation direction. Based on the contribution of each jack to the force point of the resultant thrust force of the jacks, the device outputs a jack pattern that minimizes the difference in position between the force point of the resultant thrust force and a preset recommended force point, thereby enabling the operator to quickly select an appropriate jack pattern.

As described above, the jack pattern selection support method and selection support device of the present invention are useful for setting jack patterns to control the jacks equipped on shield tunneling machines used in shield tunneling, and are particularly suitable for presenting appropriate jack patterns in a short period of time.

Claims (2)

A method for supporting selection of a jack pattern that defines the operating state of each of a plurality of jacks that are provided to propel a shield machine in an excavation direction and are arranged at equal intervals on the circumference of a circle centered on a center point of the shield machine, comprising:
In a coordinate plane formed by a horizontal axis passing through the center point, a vertical axis, and the position of the jack, a symmetry axis is set by a line connecting a preset recommended force point and the center point;
A method for supporting selection of a jack pattern, characterized in that the axis of symmetry is fine-tuned so that it passes through the position of the jack or the midpoint between two circumferentially adjacent jacks, and by utilizing the fact that the on/off states of the jack on one side of the two parts divided by the axis of symmetry and the jack on the other side are symmetrical with respect to the axis of symmetry, the jack pattern is searched for using either a combination of the on/off states of the jack on one side or a combination of the on/off states of the jack on the other side . A device for assisting in the selection of a jack pattern that defines the operating state of each of a plurality of jacks that are arranged at equal intervals on the circumference of a circle centered on the center point of the shield machine and that is provided for propelling the shield machine in the excavation direction, comprising:
a means for setting an axis of symmetry by a line connecting a preset recommended force point and the center point on a coordinate plane formed by a horizontal axis passing through the center point, a vertical axis, and the position of the jack;
A jack pattern selection support device characterized by comprising a means for fine-tuning the axis of symmetry so that it passes through the position of the jack or the midpoint between two circumferentially adjacent jacks, and by utilizing the fact that the on/off states of the jack on one side of the two parts divided by the axis of symmetry and the jack on the other side are symmetrical with respect to the axis of symmetry, searching for the jack pattern using either a combination of the on/off states of the jack on one side or a combination of the on/off states of the jack on the other side .