JP2863940B2 - Apparatus and method for calculating void volume in shield method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an apparatus and a method for calculating the volume of a void in a shield method, and more particularly, to a shield method for injecting into a void generated outside a shield machine. And a method for calculating the volume of voids.

(Prior art) Conventionally, in underground excavators such as shield moat machines,
In order to prevent land surface subsidence, backfilling work is underway to fill voids created by excavation with fast-acting concrete or the like. This backfilling operation is performed simultaneously with or immediately after shield propulsion so that the ground around the tail does not collapse, and the tail void is completely filled. At this time, the backfill injection operation is performed with the injection pressure and the injection amount as management items.

(Problems to be Solved by the Invention) However, according to the backfill injection of the above-mentioned conventional shield method, since the size of the void is not included in the control item, backfill injection may not be performed accurately. . For example, when controlling the injection source pressure, injection may be performed in an amount smaller than the required specified amount due to clogging of the tip of the injection nozzle. Further, when controlling the injection amount, if the injection pressure is higher than necessary, there is a problem that the backfill material wraps around the face and excavation becomes difficult.

The present invention focuses on the above problem, and an object of the present invention is to provide an apparatus and a method for calculating the volume of a void in a shield method capable of performing a backfill injection operation more accurately.

(Means for Solving the Problems) In order to achieve the above object, in the first invention according to the present invention, a transmitting / receiving antenna is arranged on a main body of a shield excavator, and electromagnetic waves are radiated from the shield main body to the ground. In a shield excavation machine for detecting the state of the ground, a detecting means for detecting a reflected signal larger than a predetermined value, a detecting means for detecting a zero cross of the reflected signal, and transmitting a transmission signal Time measuring means for measuring the time from detection to zero crossing, calculating means for calculating the distance between the shield body and the ground from the measured time, forward measuring means for measuring the forward distance of the shield body, The calculation unit is configured to calculate the volume of the void of the backfilling injection amount based on the distance of the mountain and the forward distance of the shield body, and display means for displaying the volume of the void. In the second invention, a transmission / reception antenna is arranged on the main body of the shield excavator, and the shield excavator detects the state of the ground by radiating electromagnetic waves from the shield main body to the ground. Detects a large reflected signal, measures the zero-crossing time from transmitting the transmitted signal of the reflected wave to receiving it, obtains the distance between the shield body and the ground, and calculates the distance and the forward distance of the shield body. The void volume of the backfill injection amount is determined from the equation.

(Operation) According to the above configuration, a transmission / reception antenna is disposed on the shield excavation machine, the distance between the ground and the shield excavation machine is obtained, and the distance between the ground and the shield excavation machine is used. Is calculated by calculation and included in management items such as comparison with the actual backfill injection amount, so that backfill injection can be performed accurately.

(Example) Hereinafter, an example of an apparatus for calculating the volume of a void in the shield method and an example of the calculation method according to the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall configuration diagram of an apparatus for calculating the volume of a void in a shield method showing a first embodiment of the present invention, FIG. 2 is a flowchart showing one embodiment of the present invention, and FIG. 3 is an operation in the present invention. It is an example figure of the reflection signal of description. Fig. 1 shows shield moat 2 while moating ground 1.
A cutter head 3 that is driven by a motor (not shown) and rotates is disposed at a front portion, and the cutter head 3 moves forward while excavating by a pressing force of a shield jack 4. In the tail part behind the shield moating machine 2, the segment 5 is usually assembled, and the backing material is filled into the backside of the segment 5 and the tail void (U) of the ground 1 by backfilling. The tail void is a gap obtained by subtracting the segment outer diameter from the skin plate outer diameter, that is, the inner diameter (Ds) of the skin plate 2a of the shield drilling machine 2 and the segment 5
The difference between the outer diameter (Dr) of the tail plate (E) and the thickness (T) of the skin plate 2a required for construction,
The gap generated between the outer periphery of the skin plate 2a and the ground after propulsion of the shield is added. The shield tunnel is constructed by repeating the assembly operation (L) of these segments. An antenna device 10 is provided on the skin plate 2a of the shield moat 2. Further, a control device 20 and a display device 30 are provided on a main body 2b of the shield moating machine 2. The antenna device 10 includes a transmitting antenna 11 for transmitting electromagnetic waves toward the ground 1, a receiving antenna 12 for receiving electromagnetic waves reflected on the ground 1, and a transmitting antenna for transmitting electromagnetic waves.
The trigger circuit 13 includes a trigger circuit 13 for generating an electromagnetic wave, a pulser 14, a sampler 15 for transmitting a received electromagnetic wave to the control device 20, and a signal processing circuit 16. The control device 20 includes a storage device 21 such as a ROM and a RAM (not shown) and an arithmetic device 22 such as a CPU.
And an interface (not shown) and an input device, and calculates the distance between the ground 1 and the shield body 2b or the backfill injection amount. The backfill injection amount calculated by the control device 20 is sent to the display device 30 that displays the result,
Display the result. A position detector 40 is mounted on the shield jack 4 to detect the amount of movement of the skin plate 2a, and sends the detected amount to the control device 20 via the signal processing circuit 16. Further, a device such as a known popper type measurement for measuring the backfill injection amount, a measurement using a flow meter, and the like, which are not shown, are arranged in the shield moating machine 2 to measure the backfill injection amount Q.

Next, the operation of the above configuration will be described. The pulse signal generated at a fixed timing by the trigger circuit 13 is controlled by the pulser 14 so as to have a predetermined pulse oscillation frequency component and power, and is sent to the transmission antenna 11. The electromagnetic wave radiated from the transmitting antenna 11 is reflected on a boundary surface of the medium such as the ground 1 and is received by the receiving antenna 12 as a reflected wave. As shown in FIG. 3, the reflected wave received by the receiving antenna 12 includes a signal component which is transmitted directly from the receiving antenna 11 to the receiving antenna 12 and interferes with target detection. That is, FIG. 3 shows an example of a signal received by the receiving antenna 12, in which the horizontal axis indicates time and the vertical axis indicates the magnitude of the reception level. 5 shows a direct wave of the emitted electromagnetic wave. Therefore, as shown in FIG.
Includes a direct wave a, it becomes difficult to detect the reflected wave b from the object. In order to cancel the direct wave a of the interference signal,
During a predetermined time t ₀ from the trigger signal in the sampler 15, as shown in (c) FIG, with masking the received signal, the predetermined reflection to improve the SN ratio by adjusting the reception level by sampler 15 Signal. The signal processing circuit 16 converts the signal into a signal corresponding to the functional characteristics of the transmission cable and transmits the signal to the control device 20. The control device 20 calculates the distance between the skin plate 2a and the ground 1 from the arrival time of the reflected wave by means described later.

Next, the operation of the present invention will be described with reference to the flowchart of FIG. 2 and the time chart of FIG. The trigger signal output from the trigger circuit 13 is a pulser 14
To start the operation of the pulser 14 and to the controller 20 via the signal processing circuit 16 to start the controller 20 (step 1). In step 2, the timer circuit is activated by the trigger signal output from the trigger circuit 13. The signal received by the arithmetic unit 22 receives a reflected signal, which is masked for a certain period of time from the trigger signal and follows after a zero signal. In step 3, a continuously input received signal is constantly checked by a zero-cross detection function to detect a rising signal passing through a zero level. When there is a rising signal, the timer value at the time of passing through the zero level is stored in the storage device 21 in step 4. Also records in step 5 the reception level S _i in the storage device 21. In step 6, the storage device
Comparing a predetermined reference value Sk and S _i that has been predetermined to 21.
If S _s −Sk <0, the process returns to step 3 to process the next reception level. If S _i −Sk> 0, the distance (M) between the ground 1 and the outer diameter of the skin plate 2 a is calculated in step 7 and recorded in the storage device 21.

Next, the sectional area of the void (step 8) is calculated using the measured distance. For example, as shown in FIG. 4, the distances Ma, Mb, and Mc between the measurement points A, B, and C are obtained, and as shown in FIG. 5, voids are developed and simplified to obtain areas N ₁ , N ₂ , N ₃ , and N. _{4 is obtained} by the following equation.

N ₁ = (πr−Wa) · Ma / 2 = (π−Θa) · r · Ma / 2 N ₂ = (Ma + Mb) · Wa / 2 = (Ma + Mb) · r · Θa / 2 N ₃ = (Mb + Mc) · Wc / 2 = (Mb + Mc) · r · Θc / 2 N ₄ = (πr-Wc) · Mc / 2 = (π-Θc) · r · Mc / 2 In the above formula, Wa = 2 Θ a · r Wb = 2 Θ c Rr = (Ds + 2T) / 2, where r is the radius of the skin plate 2a. From the above formula, the cross-sectional area Nv of the void is Here, assuming that Θa = Θc = pr, the cross-sectional area Nv of the void in the space between the ground 1 and the skin plate 2a is obtained by Nv = (Ma + Mc + 2p · Mb) rπ / 2.

Next, the cross-sectional area Nt of Teruboido the outer diameter (2r) and the outer diameter of the segment (Dr) of the skin plate 2a is ^{Nt = π (r 2 -Dr 2} /4).

Next, the volume of the void Vv and the volume of the tail void Vt are obtained in order to obtain the backfill amount when one segment (length L) is excavated.

Void volume Vv is when data sampling number per ring is 256 Here, Nv _i = (Ma _i + Mc ₁ + 2p · Mb _i ) πr / 2.

The volume of Teruboido is ^{Vt = L · π (r 2} -Dr 2/4) Therefore, the total void volume V of one segment (length L) is, Is required.

Using the total void volume V and the actual implanted injection amount Q, a ratio of the total void volume V / the actual implanted injection amount Q (step 9) is obtained. When the ratio exceeds a predetermined value, be careful. Take measures such as issuing a signal. The obtained total void volume V and the actually implanted injection amount Q are displayed on the display device 30 (step 10).

In the above-described embodiment, the injection is performed after the forward movement of one segment. However, the injection may be performed in a finer section, or the section may be divided into four sections, but may be further increased.

(Effects of the Invention) As described above, according to the present invention, the transmitting and receiving antennas are provided, the distance between the ground and the shield excavator is obtained, and the distance is used to determine the size of the void volume. Is included in the control items, so that backfill injection is performed accurately. In addition, if there is an abnormality in the backfill injection amount, it can be visually observed, so that an excellent effect that an appropriate treatment can be taken can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an apparatus for calculating the volume of a void in a shield method showing an embodiment of the present invention. FIG. 2 is a flowchart showing an embodiment of the present invention. FIG. 3 is an example of a reflected signal for explaining the operation in the present invention. FIG. 4 is a view for explaining the dimensions of the shield body and the ground in the present invention. FIG. 5 is a diagram showing the development of FIG. FIG. 6 is a view for explaining dimensions for obtaining the volume of a void. 1 ... ground mountain, 2 ... shield moat driving machine, 4 ... shield jack, 5 ... segment, 10 ... antenna device, 11 ... transmitting antenna, 12 ... receiving antenna, 13 ... trigger circuit, 14 ... Pulsa, 15 ... Sampler, 16 ... Signal processing circuit, 20 ... Control device 20, 21 ... Storage device, 22 ... Computing device, 30 ... Display device, 40 ... Position detector

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahiko Yamamoto 1200 Manda, Hiratsuka, Kanagawa Prefecture, Komatsu Ltd.Laboratory (72) Inventor Tomoyuki Abe 1200, Manda, Hiratsuka, Kanagawa Komatsu Ltd. References JP-A-63-183504 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) E21D 9/06 301 E21D 11/00

Claims (2)

(57) [Claims] 1. A shield excavator in which a transmitting / receiving antenna is provided on a main body of a shield excavator and an electromagnetic wave is radiated from the shield main body to the ground to detect a state of the ground. Detecting means for detecting a reflected signal that is also large, detecting means for detecting a zero cross of the reflected signal, time measuring means for measuring a time from transmitting a transmission signal to detecting a zero cross, and a shield body based on the measured time. Calculating means for calculating the distance between the ground and the ground; forward measuring means for measuring the forward distance of the shield body; and calculating for calculating the void volume of the backfill injection amount based on the distance between the shield body and the ground and the forward distance of the shield body. And a display means for displaying a volume of the void. 2. A shield excavator in which a transmitting / receiving antenna is provided on a main body of a shield excavation machine and an electromagnetic wave is emitted from the shield main body to the ground to detect a state of the ground. Also detects a large reflected signal,
The distance between the shield body and the ground is measured by measuring the zero-crossing time from transmitting the reflected wave transmission signal to receiving it, and the volume of the backfill injection volume is calculated from the distance and the shield body advance distance. A method for calculating the volume of voids in the shield method, wherein