JPS6085195A - Shield drilling apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to an earth pressure type shield excavator.

Hereinafter, an earth pressure type shield tunneling machine will be described with reference to FIG. 1, which shows an embodiment of the shield tunneling machine of the present invention.

This top-pressure type shield tunneling machine has a cutter wheel 2 rotatably attached to the front opening of a cylindrical shield hull 1, and a parque head I"10 is disposed behind the cutter wheel 2 to perform a cutter. A chamber 17 is formed between the wheel 2 and the bulkhead ■0.In the shield hull 1, a shield luster 3.A screw conveyor 4 is formed.
．． Cutter wheel drive motor 5 and liquid injection device 14
is installed, and the injection g9 is piped from the liquid injection device 14 to the chamber 17. In addition, 6 in the figure is a bearing for bearing the cutter wheel 2 on the bulkhead 10.

The above-mentioned earth pressure type shield excavator is operated by the drive motor 5.
The ground is excavated by driving the shield jack 3 and extending the shield jack 3 while rotating the cutter wheel. This excavated earth and sand is temporarily stored in the chamber 17 of the cutter wheel 2, and then water or a bath liquid that increases fluidity (hereinafter simply referred to as water) is poured into the chamber 1 from the injection f9.
The water, etc. and earth and sand are mixed and stirred and discharged from the chamber 17 to the outside by the screw conveyor 4.

In such a Tonosho-type shield excavator, chamber 1
7. It is serious to have vomiting and vomiting due to mud and sand inside the body.

That is, if the chamber 17 is not filled with earth and sand and there is a gap filled with water or air in the upper part, the ground at the upper front of the cutter wheel 2 will collapse and flow into the chamber 17, creating a cavity in the ground. There is a risk that the ground surface will collapse. For this reason, it is necessary to determine whether the chamber 17 is filled with earth and sand or whether the above-mentioned gap exists. However, since the chamber 17 and the inside of the shield hull 1 are shielded by the bulkhead 10, ,
The chamber 17 cannot be visually observed from inside the shield hull 1. That is, it is not possible to grasp the degree of filling of the chamber 17 with earth and sand.

Therefore, two pressure gauges, an earth pressure gauge and a pore water pressure gauge that detects only water pressure, are attached to the bulkhead 10, and the chamber 1
A method has been developed to determine the degree of soil filling within This means of understanding is based on the fact that an earth pressure gauge detects both earth pressure and water pressure caused by earth and sand, and a pore water pressure gauge detects only water pressure. , the detection value of the soil pressure gauge is larger than the detection value of the pore water pressure gauge due to the pressure valve caused by the earth and sand, whereas when the pore water pressure gauge is filled only with water, the detection value of the pore water pressure gauge and the detection value of the soil pressure gauge are larger. The values become equal, and when there is a void, the detected values of the pore water pressure gauge and the soil pressure gauge will both be zero.

However, pore water pressure gauges that only detect water pressure
A filter is attached to the front that allows only water to pass through, but
This fill is severely clogged, and in this case, it becomes impossible to accurately detect only the water pressure, resulting in a problem that the device lacks reliability.

The present invention aims to provide a shield excavator that solves the above-mentioned problems.

The present inventor has discovered that when pressure detection means, which are provided in correspondence with the bulkhead and the cutter wheel sandwiching the chamber, face each other as the cutter wheel rotates, the chamber is filled with earth and sand. We focused on the fact that the pressure fluctuations inside are large, and the pressure fluctuations are small when there is water or voids. Then, the present inventor provided a pressure detection means in correspondence with the bulkhead and the cutter wheel, sandwiching the chamber, and used the pressure means to detect pressure fluctuations in the chamber due to rotation of the cutter wheel. The above problem was solved by detecting the degree of filling of earth and sand.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the shield tunneling machine of the present invention will be described with reference to the accompanying drawings.

The shield excavator of the present invention in this embodiment has a detection rod 7 protruding into the chamber 17 on the rear surface of the cutter wheel 2, and a pressure detector 8 on the front surface of the pulp head 10.
is provided corresponding to the detection rod 7, and a suitable distance is provided between the detection rod 7 and the pressure detector 8.

A computing unit is connected to the pressure detector 8.

FIG. 2 is a block diagram from the pressure detector 8. In the figure, 8 is a pressure detector, and 18 is an amplifier connected to the pressure detector 8, which amplifies the pressure signal from the pressure detector 8.

19 is a comparator connected to the amplifier 18 and the setting device; 21 is an alarm generator connected to the comparator 19; The pressure fluctuation from 8 is calculated and compared with the set value from the setting device, and when the pressure fluctuation becomes smaller than the set value, a signal is issued to the alarm generator 21. When the alarm generator 21 receives the signal from the comparator 19, it can issue an alarm by itself using a lamp, a flash drive, etc., and can also issue an alarm signal to the outside of the alarm generator 5.

The shield tunneling machine of the present invention in this embodiment has the above-mentioned configuration, and its operation will be explained below.

3 and 4 are diagrams showing the shield excavator during excavation, in which the shield jack 3 is extended while the drive motor 5 is driven to rotate the cutter wheel 2.
to dig. This excavated earth and sand is collected in the channels 17 from the -H cutter wheel 2, and then is poured into the injection pipe 9.
Water or the like is injected into the chamber 17, and the water, etc. and earth and sand are mixed and stirred, and then discharged backward from the channels 17 by the screw conveyor 4.

At this time, the detection rod 7 rotates in the chamber 17 as the cutter wheel 2 rotates, and the detection rod 7 is connected to the pressure detector 8.
pass just in front of. Here, as shown in FIG. 3, when the inside of the chamber 17 is filled with excavated soil 13 excavated from the ground 12, when the detection rod 7 passes in front of the pressure detector 8, The earth and sand are consolidated between the tip of the detection rod 7 and the pressure detector 8, resulting in a higher pressure than at other times.

FIG. 5 shows the pressure when the chamber 17 is filled with excavated soil, where PO is the normal pressure detection value and P is the maximum pressure detection value, that is, the detection rod 7 passes just in front of the pressure detector 8. It is the value of the hour. As shown, the normal pressure detection value P.

The detector detects a pressure waveform that is significantly different from the maximum pressure detection value P. However, as shown in FIG.
7 is not filled only by excavation ± 13, and the area just in front of the pressure detector 8 is filled with water 22, etc., when the detection rod 7 passes just in front of the pressure detector 8, consolidation by earth and sand may occur. It doesn't happen. FIG. 6 shows the pressure when the chamber 17 is filled with water 22 and the like. As shown in the figure, the normal pressure detection value Po and the maximum pressure detection value P' are detected as substantially the same pressure waveform. Note that when there is a gap immediately in front of the pressure detector 8, the normal pressure detection value PO1 and the maximum pressure detection value P are both zero.

The value detected in the above manner is
The value of (maximum pressure detection value p, p' - normal pressure detection value Pa) can be calculated by n. Here, the calculated value (P, P'-P
o) is larger when filled with only excavated soil than when there is water or voids.

The calculated value (p, p' - Po) is then compared with the set value set appropriately by the setting device, and this set value is compared to the calculated value (p - P, ) when only excavated soil is used. is also small, and the calculated value when there is water or voids (P' Po
), the calculated value (p
, p'-po) is large or small, it can be distinguished whether there is only excavated soil or water or voids. Calculated value (P' Pa
) is smaller than the set value, that is, when there is water or a void, a signal is sent from the comparator 19 to the alarm generator 21, and the alarm generator 21 is activated.

This alarm lets the operator know that there is a gap caused by water or air, and take necessary action! You can avoid danger by doing so.

As is clear from the above embodiments, the shield excavator of the present invention can accurately determine whether there is a gap in the chamber based on the pressure inside the chamber, and the conventional means for determining whether there is a gap or not using a pore water pressure gauge. It can be grasped more accurately. For this reason, it is possible to detect that the ground is in a state where it is likely to collapse due to the gaps, and since a warning is issued in the event of this dangerous state, a quick response can be taken and construction is safe.

[Brief explanation of the drawing]

The attached drawings show an embodiment of the shield tunneling machine of the present invention,
Figure 1 is a vertical cross-sectional view, Figure 2 is a block diagram of the alarm generator, Figure 3 is a vertical cross-sectional view of the vicinity of the chamber when the chamber is filled with excavated soil, and Figure 4 is a vertical cross-sectional view of the chamber where the chamber is excavated. A vertical cross-sectional view of the vicinity of the chamber filled with soil and water,
FIG. 5 is a pressure detection waveform diagram when the chamber is filled with excavated soil, and FIG. 6 is a pressure detection waveform diagram when the chamber is filled with excavated soil and water. 1... Shield hull, 2... Cutter wheel, 3.
...Shield gloss, 4...Screw conveyor,
5... Drive motor, 7... Detection rod, 8... Pressure detector, 9... Injection pipe, 10... Bulkhead, 14
...Liquid injection device, 18...Amplifier, 19...Comparison calculator, Adder...Setter, 21...Alarm generator. Patent Applicant Hitachi Construction Machinery Co., Ltd. Agent Patent Attorney Tadashi Akimoto Figure 1 Figure 2 Figure 3 Figure 2 Figure 4

Claims (1)

[Claims] 1. A cutter wheel is rotatably mounted on the front opening of the shield hull, and a bulkhead is arranged behind the cutter wheel, so that a chamber is provided between the cutter wheel and the bulkhead. A shield jack, an earth and sand discharge device, a cutter wheel drive source, and a liquid injection device are arranged in the shield hull. A shield excavator characterized in that a pressure detecting means is provided correspondingly, and the pressure detecting means is capable of detecting pressure fluctuations in the chamber due to rotation of a cutter wheel to detect light temperature of earth and sand in the chamber. 2. The shield excavator according to claim 1, characterized in that the shield excavator is configured so that a warning signal is issued when the detected pressure fluctuation value is less than a set value.