JP4941861B2 - Device for measuring the competition in the tail section of a shield machine - Google Patents

Description

  In the shield machine, the segment is assembled in the tail portion of the shield machine to extend the lining, and when digging while pushing the digging machine by taking a reaction force against this, the center line direction of the lining is The present invention relates to a competition situation measuring device in a tail part in a shield machine for measuring a competition situation between a lining and an inner surface of a tail part caused by a deviation in a center line direction of the shield machine.

  In general, in the shield method, the segments are assembled in a ring shape on the inner surface of the tail portion of the shield machine to extend the lining, and a reaction force is applied to this to dig while pushing the machine. Since the outer diameter of the lining to be assembled in the shield machine is smaller than the inner diameter of the skin plate of the shield machine, there is a gap (hereinafter referred to as tail clearance) according to the construction situation.

  For this reason, in the tail portion, in order to prevent the underground water and the back material from entering the shield machine from the tail clearance, as shown in FIG. A tail seal 3 that is in sliding contact with the surface is provided. The tail seal 3 is generally provided with ring-shaped wire brushes 4, 4 that are continuous in the circumferential direction in two to three stages, a protective spring 6 is installed on the front side of each wire brush 4, and In each wire brush 4 and between both wire brushes 4, 4, a tail grease 5 is used.

  In tunnel construction in such a shield machine, when the vertical and horizontal curves are constructed, the shield machine 7 is assembled in the center line direction X1 and inside thereof by controlling the shield direction of the shield machine 7 as shown in FIG. An angle is generated in the center line direction X2 of the lining 2, and the rear end of the lining is biased in any of the circumferential directions within the tail clearance, but the bias is absorbed by the elasticity of the tail seal 3, Curve construction is possible within the allowable absorption range.

  In the conventional shield machine as described above, curved construction is possible within the range of friction of the tail seal, but it is impossible to visually check how the tail seal collapses, Tail grease leaks during digging construction, the backing material is clogged between the wire brushes, the friction range of the tail seal is often smaller than the original, and it can not withstand the preset curve construction, If the excavation is continued forcibly, the propulsion power of the shield excavator will increase and the lining and tail seal will be damaged.

  As a result, the damaged segment cannot be replaced, and a large-scale repair work occurs as a subsequent work. In addition, when the secondary lining omission segment is adopted, in addition to repairing the damaged portion, significant design changes such as the equipment and the layout thereof are required.

  For this reason, in actual curve construction, a. Measurement of clearance between lining and face by segment assembly b. Shield survey machine direction surveying and lining work type surveying c. Estimate the degree of competition between the tail seal and the lining pushed out from the operating data such as the thrust of the shield machine, and judge whether the next drill direction control instruction and segment allocation plan are appropriate However, since the work will be at one end (half day) or at the end of the day work, lack of real-time performance, if sufficient work type and direction control effect could not be obtained, subsequent segment allocation, A major review is necessary for linear management in the direction of excavation.

  Also, if management concentrates only on the direction control during excavation, the lining on the segment assembly side competes strongly against the tail seal, making it impossible to assemble the segments prepared for the next assembly operation. There were problems such as being unable to deal with the base inventory segment and being forced to produce a separate segment for correction.

  In view of such a conventional problem, the present invention prevents excessive competition with the lining in the tail portion in real time, so that damage to the tail seal and lining and the situation where the segments cannot be assembled can be avoided. It is an object of the present invention to provide a competition situation measuring device in the tail part of a shield machine that can know in real time the competition state between the tail seal and the lining pushed inside.

In order to solve the conventional problems as described above and achieve the intended purpose, the feature of the competition situation measuring device in the tail part in the shield machine of the present invention is that the shield machine machine has a predetermined part in its circumferential direction. A plurality of strain cages are installed at intervals, and when digging while pushing out the excavator by taking a reaction force against the lining by the segment assembled in the tail portion, the tail seal in the shield excavator tail portion is interposed. The strain in the tail due to the applied pressure is measured by the strain gauge.

In addition, a large number of elongated strained cages in the axial direction are embedded in the skin plate thickness at regular intervals in the circumferential direction, and the tail fixed to the inner surface of the shield machine tail section. the seal, the strain cage at regular intervals toward the circumferential direction, it is preferable to embed a number at regular intervals in the circumferential direction.

As described above, in the competing situation measuring device in the tail portion of the shield machine according to the present invention, a plurality of pressure sensors are provided at a predetermined interval in the circumferential direction at the tail seal attachment portion of the shield machine tail portion. When digging while pushing out the lining by the segment assembled in the tail portion, measuring the distribution of strain data of the strain cage in the tail portion has the following effects.

That is, during the excavation, it is possible to estimate the degree of competition between the skin plate tail portion and the segment, and it is possible to effectively contribute to the determination of the appropriateness of the segment allocation that matches the enforcement state at an early stage and the direction control.
B) Since the stress distribution can be grasped in real time, it is possible to prevent the occurrence of cracks and breakage of segments due to competition and excessive thrust increase.
C) By analyzing the measurement data for each construction, it is possible to contribute to the determination of the optimum design clearance amount.

In addition, by embedding a number of slender rod-shaped strain cages in the axial direction in the skin plate wall thickness of the tail seal attachment part in the shield machine tail part, the skin is fixed by spacing a certain distance in the circumferential direction. The stress distribution of the entire plate tail portion can be measured, and the strain cage is not exposed to the inner surface of the tail portion, so that damage during excavation work is prevented.

Further, the tail seal fixed to the shield machine tails inner surface, by embedding a large number of strain cage at regular intervals toward the circumferential direction, it is possible to accurately grasp the variations situation of the tail seal, In addition to being able to know the exact competition situation, it is possible to properly grasp changes in the flexibility of the tail seal.

Next, embodiments of the present invention will be described with reference to the drawings.

1 to 3 show reference embodiments for explaining the present invention . In the figure, 10 is a skin plate of a shield excavator. On the inner surface of the tail portion of the skin plate 10, a large number of sensor support rods 11 directed in the axial direction are provided at regular intervals in the circumferential direction.

As shown in FIG. 2, each sensor support rod 11 is embedded with a strain cage 12 made up of a number of ultra-thin load cells (foil strain gauges) at regular intervals on the surface side. A groove-shaped wiring duct 13 is formed on the back surface of the sensor support rod 11 in the longitudinal direction, and lead wires 14 connected to the respective strain cages 12 are embedded in the duct.

  As shown in FIG. 3, each sensor support rod 11 is fitted in a concave groove 16 formed on the inner surface of the tail portion of the skin plate 10, and is installed so that the strain of the skin plate 10 due to earth pressure is not transmitted. . On the outer surface of each concave groove position of the skin plate 10, a reinforcing overlay 15 is provided.

  In this way, a large number of strain cages 12 are installed on the inner peripheral surface of the tail portion of the skin plate 10 at intervals in the axial direction and the circumferential direction. As shown in FIG. A tail seal 19 composed of 18 is installed.

  In this apparatus, the pressure from the lining 20 applied to the tail portion of the shield machine through the tail seal 19 is detected by each strain cage 12, and the data is tabulated, and the lining situation of the lining against the skin plate 10 I am trying to judge.

FIG. 5 shows a first embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the part same as a reference form, and detailed description is abbreviate | omitted. In this embodiment, a so-called bar-shaped strain gauge 21 having an elongated bar shape is embedded in the thickness of the tail portion of the skin plate 10 in the axial direction. Although not shown in detail in the drawing, a large number of strain cages 21 are arranged at substantially equal intervals in the entire circumferential area of the skin plate at regular intervals in the circumferential direction.

  The tail seal 19 is fixed to the inner surface of the tail portion of the skin plate 10 in which a large number of strain cages 21 are embedded in the same manner as in the prior art.

  Once the shield machine has entered the ground, the segments are assembled continuously, so that the tail part is placed on the outer peripheral surface of the lining 20 as shown in FIG. 5 until the planned point is reached. When the wire brush 17 is in contact, the tail grease 18 permeates the wire brushes 17 and 17 on both sides, and maintains the water stop effect to prevent the inflow of groundwater and backing material and the rust preventive effect of the wire brush and the like. I am doing so.

  However, in combination with the penetration into the wire brush 17, the outflow to the outside and the adhesion and solidification of mud and backing material from the outside to the wire brush 17 occur at the same time. The effect of can not be expected. Moreover, in sharp curve construction, the clearance is extremely small, and the lining competes with the skin plate. Under such circumstances, the force that the lining 20 acts on the skin plate 10 also increases, resulting in cracking and breakage of the segments.

  In this apparatus, the pressure applied to the skin plate tail portion via the tail seal 19 is measured by detecting the strain of the skin plate 10, the pressure data is aggregated, Thus, a decrease in flexibility of the wire brush of the tail seal 19 is estimated.

FIG. 6 shows a second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the part same as a reference form, and detailed description is abbreviate | omitted. In this embodiment, the tail seal 19 is fixed in the tail portion of the skin plate 10 as in the conventional case, and the strain gauge 23 is fixed to the inner surface of the protective spring 22 on the front side of the first-stage wire brush 17. Although not shown in detail in the drawing, a large number of strain gauges 23 are arranged in the entire circumferential area of the skin plate at regular intervals in the circumferential direction.

In this apparatus, the wire brush 17 becomes flexible within the clearance between the lining 20 and the skin plate 10 and follows the clearance amount. However, as shown in FIG. 6, the solid material 24 such as the backing material flows into the base portion of the wire brush 17, and as the solidification starts, the wire brush 17 gradually becomes large and the bending margin of the wire brush 17 disappears. Then, stress is applied to the lining 20 and a strong competition occurs. At this time, the wire brush 17 and the protection spring 22 are stressed more than the normal bending state, and this is detected by each strain cage 23, and the pressure data is aggregated to measure the pressure distribution over the entire circumference. And determine the state of competition.

It is a perspective view which shows schematic structure of the reference form for demonstrating this invention . It is a perspective view which shows a sensor support rod same as the above. It is a partial expanded sectional view which shows the sensor support state with respect to a skin plate same as the above. It is sectional drawing of a use condition same as the above. It is a fragmentary sectional view showing a first embodiment of the present invention. It is a fragmentary sectional view showing a second embodiment of the present invention. It is sectional drawing which shows the tail seal of the conventional shield machine. It is a top view which shows the curve construction state of the conventional shield machine.

DESCRIPTION OF SYMBOLS 10 Skin plate 11 Sensor support rod 12,21,23 Strain gauge 13 Wiring duct 14 Lead wire 15 Concave groove 16 Overlay 17 Wire brush 18 Tail grease 19 Tail seal 20 Covering 22 Protection spring 24 Solid matter

Claims (3)

A plurality of strain cages are installed at a predetermined interval in the circumferential direction on the shield excavator tail, and the excavation machine is pushed out by pushing the excavator against the lining by the segments assembled in the tail. In the meantime , a competition state measuring device in the tail part in the shield machine, wherein the strain of the tail part due to the pressure applied through the tail seal in the shield machine is measured by the strain gauge.   The inside of the tail part in the shield machine according to claim 1, wherein the strain gauge uses a bar-like strain gauge having an elongated bar shape, and the strain gauge is embedded in the thickness of the tail part of the skin plate of the shield machine. Competition status measuring device. The competitive state measuring device in the tail part in the shield machine according to claim 1, wherein the strain gauge is fixed to an inner surface of a protective spring on the front side of the wire brush constituting the tail seal.

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