JPS62319B2 - - Google Patents

Description

Detailed Description of the Invention The present invention is designed to be assembled in the tail void of a shield machine in order to accurately and easily maintain the position of the shield machine's propulsion reaction force or lining ring during excavation work such as road access using the shield method. This invention relates to a method for effectively moving a shielding machine by locally expanding a filling bag from inside a lining ring segment into a void without any force.

As is well known, shield machines are used to excavate roads constructed underground, but depending on the circumstances of the excavation work, conventional backfilling methods may be used. It can be difficult. For example, when using a shield machine to excavate from a straight line to a sharp curve, it goes without saying that in order to change the direction of the shield machine, which has the required length, underground, it is necessary to excavate the sides of the machine to make a shield. Displacement of the tail of the aircraft is being carried out. However,
Needless to say, carrying out the extra excavation required for this direction change will result in excessive uneven distribution of space around the shield machine, which will impair the stability of the shield machine when it is propelled, and will also prevent it from turning. Since the reaction force acts on the lining ring that has already been assembled, it is difficult to avoid the meandering and pitching phenomenon when the shield machine is propelled, and of course there are many problems such as workability being lower than when moving straight.

In addition, if the excavation geology is a soft rock area or a gravel layer, the cross section excavated by the shield machine will be larger than the outer diameter of the shield machine, so the tail void will naturally be large, so the machine tail If the backfilling material was injected immediately after the assembled lining ring was sent out of the machine, the backfilling material would flow toward the shielding machine, which would unavoidably require a significant amount of backfilling. It will be done late. For this reason, the lining ring meandered around the axis of the excavated tunnel,
Alternatively, there are problems such as pitting, or a combination of these, making it difficult to bury the lining ring correctly.

Therefore, as a means to solve this problem, a method is used in which a special bag is placed around the entire outer periphery of the lining segment to form a barrier that prevents the backfilling material from flowing toward the shielding machine. has been proposed, but this type has problems such as uniform expansion of the bag, which makes it difficult to use, and the bag cannot be filled locally.

In view of this situation, as a means to solve this problem, the lining ring was assembled in sequence by connecting it to the tail of the shielding machine, and the lining ring was assembled in sequence before backfilling was injected into the ground. From the inside of the segment, between its back surface and the ground, an injecting material that provides early setting strength, such as a backfilling material, is injected into the bag that has been assembled in advance with the segment to bulge the bag. By forming a lump-shaped local fixed object in the void area through the bulge and holding the reaction force in the ground by this bulging lump, the lining ring is stabilized and shield excavation work is streamlined. We obtained a local fixing method that contributes to the acceleration of the process, but when implementing this method, the pressure of filling material injected into the bag that bulges into the void area is relatively high, so the bag may be damaged at the same time as injection. In the event of an accident, or if the bag is damaged before condensation due to applying more filling pressure than necessary when the goal has been achieved, local fixation will not be possible and the injection material will be poured into the space unnecessarily. It was found that it was difficult to confirm whether or not the objectives and means were being carried out reliably.
In short, it is necessary for the workers to be able to accurately grasp that the bulging bag for holding local reaction force will swell and be able to take a reaction force against the ground, but this cannot be confirmed rationally. However, it was insufficient to do it by hand, so to speak.

In the present invention, such unresolved issues can be resolved and the lining ring can be locally fixed at the work area accurately, preventing damage to the bulging bag and relying solely on the operator's intuition. To provide a local fixation method that allows the operation to be performed rationally by visually observing the injection state for local fixation at the working position without causing any problems.

The present invention makes it possible to attach a local fixing device consisting of an expansion bag that is accommodated and installed so as to be able to expand to the rear side and a support cylinder for the expansion bag at an appropriate position of a required segment of a lining ring used in the shield construction method. The expansion bag to be incorporated into this local fixation device is one in which a preliminary chamber is formed on the outside from the seam by sewing appropriate parts inside the outer periphery with a force weaker than the maximum pressure applied, and using a shield machine. When the local fixation device is attached to the installation port provided at the appropriate location of the segment according to the excavation work conditions, and the injection material with high early setting strength is injected from the inside of the segment into the expansion bag inside the fixation device. A pressure gauge is interposed on the injection side, and when the inflation bag is inflated by protruding from the injection material to the outside of the segment, the partition seam with the preliminary chamber is ruptured to temporarily reduce the internal pressure of the inflation bag, and then After reading with a pressure gauge that the required injection pressure has been restored, the lining ring segment is locally held in the ground by the injection material that solidifies inside the bag bulged between the ground and the segment. That's what I did.

Therefore, in the bulging bag of the present invention, a spare space (preliminary chamber) for preventing rupture and for checking filling and preventing rupture is formed in a part of the bag, such as at the corner of the tip of the bag or on both sides, where injection can be performed without damaging the bag. It is possible to use a bag that is formed in a location suitable for inflating without impairing the filling of the material, and the shape of the bag does not need to be any special shape, as long as it is a normal square bag.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the drawings with reference to embodiments.

First, what is shown in FIG. 1 is a specific example of a local fixation device used in the construction method of the present invention. The outer tube 2, the expansion bag 6, the guide cylinder 3 forming a space for accommodating the expansion bag 6, the injection tube 4 for the injection material, and the opening of the expansion bag 6. A mounting ring 5 for fixing is arranged as shown in the figure, and the expansion bag 6 is attached to the base end of the guide tube 3 whose base end is fitted into the mounting ring 5 fixed inside the exterior tube 2. The protective cap 7 is temporarily fixed to the tip of the guide tube 3 by, for example, caulking, and then the bag is secured to the inside of the guide tube 3 for a sufficient length. The bottom part is designed not to be damaged by external force, and the expanded bag 6 is made of water-permeable cloth with appropriate seams and has high tensile strength, and the shape when expanded is cylindrical, conical, etc. Any shape such as a spherical shape can be adopted. And this bulging bag 6 has a second
As shown in the figure, a tearing seam 6'' is provided at a corner of the bag 6' with an appropriate space, and the sewing thread of this seam 6'' is made weaker than the strength of the bag-forming seam. (The injection pressure of the injection material is generally about 2 to 3 kg/cm ² , and the bag is sewn to be able to withstand this injection pressure.) The outside of this sewn part 6'' constitutes the preliminary chamber 6a. An injection pipe 4 is provided at the center of the mounting ring 5, protruding inside the guide cylinder 3, and is connected to the injection pipe 4 via a joint and a supply pipe for injection material via a joint 14 or a check valve. It is now connected to

Such a local fixing device 1 is used by being attached to a mounting hole 11 provided in a segment, and in order to use such a local fixing device to fix a segment to the ground, it is necessary to take into consideration the conditions of the work site. Corresponding measures need to be adopted. That is, when using the lining ring in a straight line, a plurality of mounting holes 11 (which can be used in common with general backfilling material injection ports) are provided in advance in the segments of the lining ring, and before backfilling is performed. In places where it is considered necessary to fix the segment to the ground,
As shown in FIG. 3, the outer tube 2 of the local fixation device 1 is attached to the attachment port 11 at the required location of the segment 10,
In addition, a connecting pipe 15 with a socket 14 (or a check valve) connected to the injection pipe 4 is connected to the injection material supply pipe, and a T-shaped joint 17 is interposed near the socket 14 to create a shutoff chamber by a diaphragm. A pressure gauge 16 is attached to the guide cylinder 3 through the injection pipe 4 so that the state of injection into the swelling bag 6 can be confirmed.
When the injection material is press-fitted into the inflation bag 6 housed inside, the injection pressure (generally about 2 to 3 kg/cm ² ) will cause the protective cap 7 at the end of the guide tube 3 to come off and release the inflation bag 6.
pops out into the air circumferential part C and swells until it sufficiently contacts the ground A, and if the filling amount of the injection material D is approximately the volume of the bulge bag 6 excluding the preliminary chamber 6a, it is filled to the bulging permissible state. Pressure gauge 1 installed in the injection material supply pipeline
6 indicates the required injection pressure, but when it is filled, the sewing thread of the sewn part 6'' that partitions the preliminary chamber 6a breaks and the sewn part 6'' opens, so at that moment the inside of the bag body 6'' is and the pre-chamber 6a communicate with each other, the volume inside the bag increases momentarily, and as a result, the pressure inside the bag 6 decreases, so naturally the pressure indicated on the pressure gauge 16 decreases momentarily.
Eventually, the injection material D is replenished into the bulging bag 6, which now has room, and fills up, thereby restoring the original pressure, and the pressure gauge 16 indicates this state. The injection operator visually observes this state and confirms the displacement of the pressure gauge, and if the injection pressure increases as described above, once it drops, then recovers, and is maintained as it is.
At that time, the filling amount of the injection material D is filled with the bag 6 in the bulged state, and by stopping this injection, the injection material D is solidified, and as a result, the bulging bag 6 is filled with the injection material. Segment 10 with D
It hardens into a local lump B between the back surface of the rock and the ground A, forming a so-called tension. At this time, residual gas and moisture inside the inflation bag are released from the seams, allowing the injection material to be quickly filled and the bag to expand accordingly, allowing the intended operation to be completed in an extremely short period of time. At the same time, setting of the injection material progresses and locally sets. An example of using a material with high early setting strength as the injection material is a standard mixture of 250 kg of ordinary Portland cement, 250 kg of something like clay sand as an aggregate, and a foaming agent (such as an aeon activator). Polyoxyalkylene (a mixture with an alkyl ether type nonionic activator and a parent colloid polymeric foaming stabilizer, etc.) 2.0Kg, stabilizer 2.5Kg, and water 360Kg, approximately 31 of the total volume of these. % of air is mixed as liquid A, and a water glass-based plastic strength modifier is used as liquid B of 208 kg. By mixing and injecting both liquids, it quickly becomes jelly-like after mixing, and becomes liquid B. Therefore, it is stable even when filled in the swelling liquid, and solidification occurs rapidly, making it easy to obtain early strength. (It is not limited to only injection materials with such ingredients.) In this way, since the injection material used has the property of rapidly setting,
Even if a part of the bag ruptures after bulging, the bulge that has been formed will not lose its shape and will just leak out from the rupture part and will eventually solidify, achieving the purpose. It can be done. By supplying injection material sequentially or all at once to the required number of local fixing devices 1 attached to each segment arranged around the lining ring assembled in the manner described above, the lining ring The excavated ground will be securely supported and fixed locally at several locations. At this time, in the upper half of the periphery, although the bulging bag 6 that protrudes from the segment 10 into the space C will hang down along the back side due to gravity, the flexibility of the bulging bag 6 will prevent the injection. When the material is filled, it can easily be brought into contact with and fixed to the ground A.

Therefore, according to the method of the present invention, it is possible to easily solve problems in excavation work that draws sharp curves in shield construction in recent urban civil engineering, and during this work, the problems shown in Figs. 4 and 5 can be easily solved. As shown, the required segment corresponding to the over-excavated side has 1
Each segment is provided with one or more attachment ports in the circumferential direction, and a local fixation device 1 is attached to each attachment port 11 of this segment 10, and each local fixation device 1 is attached simultaneously or in the same manner as described above. By sequentially operating segment 1
Despite the fact that a plurality of bulging bags 6 protrude between the back surface of 0 and the ground A, and the lumps B congealed by filling with the injection material are uneven in the distance between the ground A and the segment 10. , butt against each other depending on the state of their opposing positions, and as a result, the lining ring is stably fixed to the ground of the excavated part. Therefore, the propulsion reaction force during the shield machine's curved movement can be directly applied to the lining ring, and as a result, even if there is a large amount of excess excavation, the excavation can be carried out in a stable state without any problems. If local fixing is performed in this way, it will be possible to proceed without immediately backfilling, depending on the geology of the site, and by increasing the number of local fixings, the voids will be reduced and the shielding mechanism of the backfill material will be improved. By using a backfilling material that has a fast setting speed and high early strength properties, it is possible to prevent the backfilling material from flowing toward the shielding machine side. Injection work can be carried out by blocking this and quickly backfilling from the injection port of another segment (taper ring part, etc.).
This makes it possible to prevent the collapse of the ground, allowing for more effective shield excavation work on steep curves.

After the injection material D has solidified in each local fixation device 1, unscrew the outer tube 2 from the segment 10 attachment port 11 and use the screwdriver to remove the precipitated bulge bag 6 and the part fixed to the outer tube 2. In order to make the cutting easier, the guide tube 3 and injection tube 4 are
(This is not necessary when the injection pipe is shortened.) Cut grooves 3' and 4' are provided on the outer circumferential surface at the position corresponding to the screwed end of the armored tube 2. When the armored tube 2 is removed, the condensation side remains. Therefore, by cutting the bag at the inlet end of the segment opened by removing the outer tube 2, the part protruding inside the segment of the device is completely removed, and the part protruding inside the segment of the device is completely removed, which will hinder the subsequent work. That is not the case.

As described above, according to the method of the present invention, the injection material is locally injected and bulged into the space between the segment and the ground through the bulge bag, and when the lining ring is locally fixed, A spare space is formed in the fixation inflation bag by dividing it with a breakable sewn part, and when the required injection material is press-fitted into this inflation bag and inflated, the partition sewn part is broken. By temporarily reducing the pressure inside the bag and preventing the bulging bag from bursting due to rapid expansion, the change in injection pressure can be read using the pressure gauge attached to the injection tube. By making it possible to check the local fixing operation using the bulge bag at the work site, it is now possible to perform the fixing work between the ground and the lining ring in a rational manner, solving the conventional problems with the shield method and facilitating smooth excavation. This has made it possible to promote work.

In addition, according to the local fixed support means of the present invention, as pre-treatment for backfilling of lining work at an excavation site using the shield method in a stable stratum such as a soft rock stratum,
Of course, it can also be used for the purpose of aligning the axis of the lining ring with the axis of excavation, and can be handled effectively.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway vertical cross-sectional view of a local fixation device used to carry out the method of the present invention, Fig. 2 is a plan view of a specific example of an inflatable bag, and Fig. 3 is a partial view showing the operation mode. The vertical sectional view, FIGS. 4 and 5 are views showing examples of support modes in curved excavation work. DESCRIPTION OF SYMBOLS 1... Local fixation device, 2... Exterior tube, 3... Guide cylinder, 4... Injection tube, 6... Expansion bag, 6'... Bag body, 6''...
Sewing section, 6a...Preliminary room, 10...Segment, 11
...Attachment port, 14...Kotuku, 15...Connection pipe, 16...
Pressure gauge, 17...T-shaped joint, A...ground, B...bulging bump, C...space, D...injection material.

Claims (1)

[Claims] 1. A local fixing device consisting of an expansion bag and its supporting cylinder is installed in the appropriate position of the required lining ring segment used in the shield method so that it can expand to the rear side, and is installed under the excavation conditions of the shield machine. The inflatable bag incorporating this local fixation device has a preliminary chamber formed on the outside by partitioning appropriate points inside the outer periphery with a sewn part that is weaker than the force exerted by the maximum pressure. When injecting an injection material with high early setting strength into the expansion bag inside the fixing device from the inside of the segment, a pressure gauge was interposed on the injection side, and the injection material caused the expansion bag to protrude to the outside of the segment and inflate it. At this time, the internal pressure of the bulge bag is temporarily lowered by breaking the sewn part separating it from the preliminary chamber, and then the pressure gauge is used to confirm that the pressure has returned to the required injection pressure. A method for fixing and supporting a lining ring in a shield construction method, which is characterized by locally holding the lining ring segment to the ground using an injection material that congeals inside the bag.