JP2013007169A - Back-filling layer having water permeability partially and method for forming the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form a back-filling layer with water permeability.SOLUTION: Back-filling materials (U1 and U2) in a flow state are injected in a space (tail void 3) between a lining body 2 in a foundation G and the foundation G and is hardened, so that a back-filling layer 4 is formed to cover the outer peripheral surface of the lining body 2. The back-filling layer 4 comprises a water permeable part 5 which is formed in a part in the circumferential direction by the injection of the water permeable back-filling material U1 and which has a water passage thereinside, and a non-permeable part 6 which is formed in the other part in the circumferential direction by the injection of the non-permeable back-filling material U2 and which does not have a water passage thereinside.

Description

  The present invention relates to a backfill layer partially having water permeability and a method for forming the same.

  In the past, in order to form a detour of water flow on the outer periphery of the lining body, a technique for filling a backfill material that develops water permeability after curing has been proposed between the segment and the ground. For example, Patent Document 1 discloses a backfill material in which an alkaline curing material, a water-absorbing material that dehydrates and shrinks in an alkaline environment, and an expansion agent that reacts in an alkaline environment to generate gas are mixed. Are listed. When this backfilling material is filled in the gap between the ground and the covering body and cured, a water-permeable backfilling layer is formed over the entire periphery of the covering body.

JP 2011-57876 A

  The backfill layer that has water permeability over the entire circumference of the lining body requires more manufacturing processes than the backfill layer that does not have water permeability, and it is also necessary to use expensive materials. is there. For this reason, there is a problem that the cost becomes high.

  This invention is made | formed in view of such a situation, The objective is to form easily the backfill layer which has water permeability.

  In order to solve the above-mentioned problem, the present invention injects a fluidized backfill material into a gap between the lining body built in the ground and the ground, and cures the outer peripheral surface of the lining body. A back-filling layer formed in a covering state, formed in a portion in the circumferential direction by injection of a water-permeable back-filling material, and a water-permeable portion having a water passage inside the layer, and a water-impermeable back-filling material And a non-permeable portion that does not have the water passage inside the layer.

  According to this backfilling layer, since necessary portions of the backfilling layer are configured as water permeable portions, the manufacturing process can be rationalized rather than forming a backfilling layer having water permeability as a whole.

  In the present invention, when the water-permeable portion is provided by communicating a plurality of voids formed in the cured material in a cured state, the voids communicate with each other to provide water permeability. A path can be formed reliably.

  In the present invention, when the water-impermeable portion is formed on the outer surface of the lining body, the water-impermeable portion is formed above the water-permeable portion. Therefore, the water stoppage of the tunnel can be enhanced against the groundwater flowing down the ground.

  In the present invention, the water-permeable backfilling material reacts in an alkaline environment with an alkaline curing material that cures over time from a fluid state, a water-absorbing material that dehydrates and shrinks in an alkaline environment, and gas in an alkaline environment. It is preferable that the water-impermeable backing material includes a hardener that is cured from the fluid state with time.

  According to the backfill layer, since the water-absorbing material is dehydrated and gas is generated by utilizing the fact that the hardener is alkaline, no special treatment is required. For this reason, a process can be simplified.

  In the present invention, the water-permeable portion is formed by injecting the water-permeable backfilling material mixed with the curing material, the water-absorbing material, and the expansion agent into a gap between the covering body and the ground. The water-impermeable portion is formed by injecting the water-impermeable back-filling material including a hardener for the water-permeable back-filling material into a gap between the covering body and the ground. preferable.

  According to this backfill layer, the hardener for the water-permeable backfill material is used as the hardener for the non-water-permeable backfill material. For this reason, the switching operation between the water-permeable backfill material and the non-water-permeable backfill material can be facilitated.

  Further, the present invention is to inject and cure a backfill material in a fluid state through an inlet provided in the lining body into a gap between the lining body constructed in the ground and the ground, A method for forming a backfill layer in which a backfill layer is formed so as to cover an outer peripheral surface of the cover body, wherein one of a water-permeable backfill material and a non-water-permeable backfill material is passed through the inlet. After performing the first injection operation for injecting into the gap between the ground and the ground, the other of the water-permeable backfill material and the non-water-permeable backfill material is passed through the injection port between the cover body and the ground. By performing the second injection operation of injecting into the layer, one of the water-permeable portion having a water passage inside the layer and the non-water-permeable portion not having the water passage inside the layer, the cover body and the ground Formed in a part including the lower end in the circumferential direction in the gap between the water-permeable part and the water-impermeable part On the other hand, and thereby forming the remaining portion including the circumferential direction of the upper end of the gap between the ground and the lining member.

  In this forming method, since the injection port is shared by the first injection operation and the second injection operation, the number of injection ports can be suppressed, and the configuration of the covering body can be simplified.

  According to the present invention, a water-permeable backfill layer can be easily formed.

It is sectional drawing explaining the backfill layer which has a water-permeable part and a non-water-permeable part. It is sectional drawing explaining the structure of a shield machine. (A) is a figure explaining a backfilling material manufacturing department. (B) is a figure explaining the mixing | blending of A material, B material, and C material used in a backfilling material manufacturing part. It is a figure explaining the injection | pouring process of a water-permeable backfilling material. It is a figure explaining the injection | pouring process of a water-impermeable backfill material. It is a figure explaining the state which injection | pouring of the backfilling material was completed. It is a figure explaining embodiment which provided the water-permeable part above the non-water-permeable part. It is a figure explaining embodiment which formed the backfill layer which has a water-permeable part and a non-water-permeable part in a part in the longitudinal direction of a shield tunnel. It is a figure explaining embodiment which formed the backfill layer which has a water-permeable part and a water-impermeable part, and the backfill layer which has only a water-impermeable part alternately for every shield ring.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. A shield tunnel 1 shown in FIG. 1 includes a covering body 2 and a backfill layer 4 formed in a tail void 3 that is a gap between the covering body 2 and the ground G. The backfill layer 4 is formed so as to cover the entire outer peripheral surface of the lining body 2, and has a water-permeable portion 5 having a water passage inside the layer, and a water passage having no water passage inside the layer. And a water permeable portion 6.

  In this embodiment, a part of the backfill layer 4 in the circumferential direction is a water permeable part 5 and the remaining part is a non-water permeable part 6. That is, the non-water-permeable part 6 is formed above the water-permeable part 5. Specifically, the water-permeable portion 5 and the non-water-permeable portion 6 are separated at the 2 o'clock and 10 o'clock positions on the dial of the watch, and the lower side passing through the outer peripheral lower end (6 o'clock position) of the covering body 2 The water-permeable part 5 is formed in the part, and the non-water-permeable part 6 is formed in the upper part passing through the outer peripheral upper end (position at 12 o'clock).

  The shield tunnel 1 is buried at the depth of the water permeable layer Ga in the ground G. However, since the backfill layer 4 has the water permeable portion 5, as shown by an arrow in FIG. The upstream groundwater flows counterclockwise along the water permeable portion 5 and flows downstream through the lower surface side of the shield tunnel 1. For this reason, the flow of groundwater is not blocked by the constructed shield tunnel 1.

  In this shield tunnel 1, since a necessary portion in the circumferential direction of the backfill layer 4 is configured as the water permeable portion 5, the manufacturing process can be streamlined rather than forming a conventional backfill layer having water permeability as a whole. Can be planned. Moreover, in this backfill layer 4, since the non-water-permeable part 6 whose intensity | strength is larger than the water-permeable part 5 is formed in the upper part of the lining body 2, compared with the conventional water-permeable backfill layer, it is vertical soil. The resistance to pressure can be increased. Furthermore, the waterproofness of the tunnel can be increased with respect to the groundwater (rain water or the like) that has permeated through the ground G from above the shield tunnel 1. Thus, the water impermeable portion 6 can also function as a water shielding layer.

  Next, formation of the backfill layer 4 of this embodiment will be described. First, the shield machine 10 will be described with reference to FIG. The illustrated shield machine 10 includes a hood part 11, a girder part 12, and a tail part 13. The hood part 11 is a part to which the cutter 14 for excavating the ground is attached in a rotatable state. The girder portion 12 has an internal space in which a driving device 15 for the cutter 14, a soil removal mechanism (not shown) for discharging the earth and sand excavated by the cutter 14, and a plurality of shield jacks 16 for advancing the shield machine 10. It is the part attached to. The tail portion 13 is a cylindrical portion connected to the hood portion 11, and an erector 17 for assembling the segment SG is installed therein. A backfilling material manufacturing section 20 is provided behind the tail section 13 (left side in FIG. 2).

  The backfilling material manufacturing unit 20 manufactures a backfilling material. In this embodiment, as shown in FIG. 3A, the A material manufacturing unit 21, the B material manufacturing unit 22, and the C material manufacturing unit 23 are used. have. The A material manufacturing unit 21 is a part that manufactures the A material, and includes an A material agitator 21a and an A material pump 21b. And A material mixed with A material agitator 21a is sent through piping by A material pump 21b. Similarly, the B material manufacturing unit 22 is a part for manufacturing the B material, and has a B material tank 22a and a B material pump 22b, and the C material manufacturing unit 23 is a part for manufacturing the C material. And a C material agitator 23a and a C material pump 23b. In addition, you may install A material manufacturing part 21 outside a mine.

  The A material, the B material, and the C material are materials constituting the backfill material. As shown in FIG. 3B, the A material is a mixture of slag cement-based mortar and an expanding agent, the B material contains a coagulant, and the C material contains a water-absorbing material. It has been done. And the slag cement type | mold mortar contained in A material and the condensing material contained in B material function as a hardening | curing material.

  The A material contains a main material, an auxiliary material, an expansion agent, and a stabilizer. And the main material except a swelling agent, an auxiliary material, and a stabilizer comprise slag cement type mortar. In this embodiment, a product of Taiheiyo Shield Mechanics Co., Ltd. was used as the slag cement mortar. Specifically, s-height was used as the main material, auxiliary material-S was used as the auxiliary material, and SP-R was used as the stabilizer.

  The swelling agent has a property of swelling by reaction. As such a swelling agent, an acrylic acid copolymer salt or a maleic acid copolymer salt having water absorption in an alkaline environment can be used. In this embodiment, F former (manufactured by Celltec Corporation) sold by Taiheiyo Shield Mechanics Co., Ltd. was used. This F former has the property of reacting in an alkaline environment to generate hydrogen gas and to expand along with it.

  In the A material manufacturing section 21, the main material, auxiliary material, expansion agent, stabilizer, and tap water are introduced into the A material agitator 21a and mixed to manufacture the A material, which is sent out by the A material pump 21b. Such A material shows alkalinity since it contains an alkali component (calcium hydroxide, quicklime, etc.) in the main material.

  The coagulant contained in the B material is for curing the slag cement-based mortar contained in the A material in a short time. For example, special water glass is used. In this embodiment, SP-70 manufactured by Taiheiyo Shield Mechanics Co., Ltd. was used as the condensing material. And in the B material manufacturing part 22, the special water glass stored in the B material tank 22a is sent out by the B material pump 22b.

  The water-absorbing material contained in the C material has a high water retention performance and also has a property of releasing water retained by the reaction and contracting. As such a water-absorbing material, a water-absorbing polymer comprising a polyacrylate cross-linked polymer can be used. This water-absorbing polymer can absorb and hold water several tens to several hundred times as much as its own weight, while it releases the water held in an alkaline environment and contracts. And in C material manufacturing part 23, water absorbing polymer and tap water are thrown into C material agitator 23a, C material is manufactured by mixing, and it sends out by C material pump 23b.

  These A material, B material, and C material are mixed immediately before being injected into the tail void 3. As shown in FIG. 3B, in the backfilling material manufacturing unit 20, the first line mixer 24 and the second line mixer 25 are provided in series, and the first line mixer 24 uses the A material and the C material. And the B material is further mixed with the mixture of the A material and the C material by the second line mixer 25 to produce a backfill material.

  Here, in this embodiment, by mixing all of the A material, the B material, and the C material, a water permeable backfill material for forming the water permeable portion 5 is manufactured, and the A material and the B material are combined. The impermeable backing material for forming the impermeable portion 6 by mixing is manufactured.

  That is, when all of the A material is mixed from the A material, the hardened material (the slag cement mortar of the A material + the condensed material of the B material) remains embracing the water absorbing material (the water absorbing polymer of the C material) in the water absorbing state. On the other hand, the water-absorbing material shrinks by releasing water due to the alkali component while forming a void in the cured material. Further, the expansion agent (A material) generates hydrogen gas by an alkali component to widen the gaps, and cracks that connect the gaps are formed. A water passage is formed by these gaps and cracks, and the water-permeable portion 5 having water permeability is formed.

  On the other hand, when only the A material and the B material are mixed, the expanding agent generates hydrogen gas, but since there is no water absorbing material, the hydrogen gas presses the curing material, and the inside of the curing material is more filled. . Thereby, the passage of water is not formed and it becomes the non-water-permeable part 6 which does not have water permeability.

  Therefore, when manufacturing a water-permeable backfill material, the A material pump 21b, the B material pump 22b, and the C material pump 23b are operated. On the other hand, when manufacturing a water-impermeable backfill material, the C material pump 23b is stopped and the A material pump 21b and the B material pump 22b are operated. If comprised in this way, manufacture of a water-permeable backfilling material and manufacture of a water-impermeable backfilling material can be easily switched by selectively operating C material pump 23b.

  As shown in FIG. 2, the back filling material (water permeable back filling material, non-water permeable back filling material) manufactured by the back filling material manufacturing unit 20 is sent through the injection hose 26 and injected into the tail void 3. . That is, the tip of the injection hose 26 is attached to the injection port 2 a provided in the existing segment SG, and the backfill material is sent out from the backfill material manufacturing unit 20. As a result, the backfill material is injected into the tail void 3 through the injection port 2a.

  In the present embodiment, since each material (A material to C material) is mixed immediately before being injected into the tail void 3, the time when the hardener is cured, the time when the water-absorbing material is shrunk, and the expansion agent is gas. It is possible to harmonize with the time of generating. That is, since the water absorbent material can be contracted in a state where the cured material is cured to some extent, a void accompanying the shrinkage of the water absorbent material can be formed inside the cured material. Moreover, since hydrogen gas by the expanding agent can be generated in a state where the voids are formed, cracks can be formed in the hardened material, and the voids can be communicated with each other by the cracks.

  Next, the procedure for forming the backfill layer 4 will be described. As shown in FIG. 4, when a plurality of segments SG are joined to form a ring-shaped portion (referred to as a segment ring SL for convenience), a tail void 3 that is a gap between the outer surface of the segment ring SL and the ground G A water permeable backfill material U1 is injected into the slag. In this case, the injection hose 26 is attached to the two injection ports 2a provided at the 2 o'clock and 10 o'clock positions, and the valve 26a provided in the middle of the injection hose 26 is opened. Then, by operating the A material pump 21b, the B material pump 22b, and the C material pump 23b, the water permeable backfill material U1 in which the A material, the B material, and the C material are mixed is manufactured. Inject (first injection operation).

  If the injection of the water permeable backfill material U1 is continued while monitoring the supply amount and the supply pressure, and the required amount of the water permeable backfill material U1 is injected (for example, below the respective inlets 2a in the tail void 3) If the range is filled with the permeable backfill material U1, injection of the non-permeable backfill material U2 is started (second injection operation). As described above, the backfilling material manufacturing unit 20 of the present embodiment manufactures the non-permeable backfilling material U2 by stopping the supply of the C material. As a result, as shown in FIG. 5, the non-permeable backfill material U <b> 2 is injected into a portion of the tail void 3 above each injection port 2 a.

  As shown in FIG. 6, when the top of the tail void 3 is filled with the non-permeable backfill material U2, the injection of the non-permeable backfill material U2 is stopped. That is, the A material pump 21b and the B material pump 22b are stopped, and the valve 26a of the injection hose 26 is closed.

  The water-permeable backfill material U1 and the water-impermeable backfill material U2 injected into the tail void 3 are cured with the passage of time to become a water-permeable portion 5 and a water-impermeable portion 6, respectively.

  First, the water-permeable portion 5 will be described. First, the hardened material contained in the water-permeable backfill material U1, that is, the slag cement-based mortar in the A material reacts with the condensed material in the B material, and the water absorption contained in the C material. It hardens in the state where it embraced the property polymer. Thereafter, due to the alkali component in the A material, the water-absorbing polymer in the C material releases water and contracts, and a void is formed inside the cured material. Moreover, the expansion agent in A material reacts with the alkali component in A material, and generates hydrogen gas. This hydrogen gas acts so as to push each gap formed by the shrinkage of the water-absorbing polymer, and causes cracks between the gaps. The cracks and the gaps communicated by the cracks form water passages, and the water-permeable portion 5 exhibits water permeability.

  Next, the water impermeable portion 6 will be described. Even in the non-permeable backfill material U2, the hardener (slag cement-based mortar in the A material and the condensed material in the B material) reacts and hardens. Here, since C material (water-absorbing material) is not mixed with the water-impermeable backing material U2, no void is formed in the cured material. For this reason, even if the expansion agent in the A material reacts to generate hydrogen gas, no water passage is formed in the water-impermeable portion 6. As a result, the water impermeable portion 6 does not have water permeability.

  In this way, the backfill materials U1 and U2 are injected into the tail void 3 corresponding to a certain segment ring SL. Since the backfilling materials U1 and U2 are injected for each segment ring SL, the backfilling layer 4 formed in advance is inherited to maintain continuity. Therefore, the backfill layer 4 can be reliably formed over the entire outer peripheral surface of the lining body 2.

  As described above, in this embodiment, after injecting the water-permeable backfill material U1 from the inlet 2a, the water-permeable portion 5 and the water-impermeable water are injected by injecting the water-impermeable backfill material U2 from the same inlet 2a. The sex part 6 is formed. Thus, since the injection port 2a is shared, the number of injection ports 2a can be suppressed and the structure of segment ring SL (covering body 2) can be simplified.

  In the present embodiment, the water-absorbing material is contracted (dehydrated) and hydrogen gas is generated by utilizing the fact that the curing material is alkaline, so that the water-permeable portion 5 in the backfill layer 4 is formed. In doing so, it is sufficient to inject the water-permeable backfill material U1, and no special treatment such as heating or additional material addition is required. For this reason, the backfill layer 4 having water permeability can be easily formed. And since a space | gap is connected and water permeability is provided, the passage of water can be formed reliably.

  Further, when the expansion agent contained in the water permeable portion 5 (water permeable backfill material U1) generates hydrogen gas, the non-water permeable portion 6 (non-water permeable backfill material U2) is also cured. For this reason, the non-water-permeable part 6 suppresses the water-permeable part 5 from above, and blocks the escape path of hydrogen gas. Thereby, it becomes easy to act so that hydrogen gas may expand a space | gap, and the number of the cracks produced between space | gap can be increased. As described above, since this crack becomes a passage for water, the water permeability of the water permeable portion 5 can be increased.

  The above description of the embodiment is for facilitating the understanding of the present invention, and does not limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof. For example, you may comprise as follows.

  The above-described backfill layer 4 has the non-permeable portion 6 formed on the upper portion of the covering body 2 and the permeable portion 5 formed below the non-permeable portion 6, but is not limited to this configuration. For example, as shown in FIG. 7, the water-permeable portion 5 may be formed in the upper portion of the covering body 2, and the non-water-permeable portion 6 may be formed below the water-permeable portion 5. This configuration is advantageous when the water-permeable layer Ga sandwiched between the water-impermeable layers is present at the top of the shield tunnel 1. In addition, in which range in the outer peripheral part of the lining body 2 the permeable part 5 and the non-permeable part 6 are formed can be arbitrarily determined.

  Further, as shown in FIG. 8, a partially permeable backfill layer 4 having a water permeable portion 5 and a water permeable portion 6 is formed in a part of the shield tunnel 1 in the longitudinal direction, and the other portion is water permeable. The backfill layer 4 ′ may be formed. This form is suitably used, for example, when the shield tunnel 1 is constructed so as to cross the water-permeable layer Ga in the ground. Further, as shown in FIG. 9, the partially water-permeable backfill layer 4 and the non-water-permeable backfill layer 4 ′ may be alternately formed.

  In the above-described embodiment, a water-permeable backfilling material comprising an alkaline curing material, a water-absorbing material that dehydrates and contracts in an alkaline environment, and an expansion agent that reacts in an alkaline environment to generate gas. Although illustrated, other types of water permeable backfill materials may be used. For example, a water-permeable backfilling material having a cellulosic thickener that is biodegradable may be used. Further, a material obtained by adding water-soluble or heat-soluble soluble fibers made of collagen such as gelatin or glue to a concrete base material may be used as a water-permeable backfill material. .

DESCRIPTION OF SYMBOLS 1 ... Shield tunnel, 2 ... Cover body, 2a ... Backfill material injection port, 3 ... Tail void, 4 ... Partially permeable backfill layer, 4 '... Non-permeable backfill layer, 5 ... Permeable part, 6 ... Non-permeable part, 10 ... Shield machine, 11 ... Hood part, 12 ... Girder part, 13 ... Tail part, 14 ... Cutter, 15 ... Cutter drive device, 16 ... Shield jack, 17 ... Elector, 20 ... Backfill Material Manufacturing Department, 21 ... A Material Manufacturing Department, 21a ... A Material Agitator, 21b ... A Material Pump, 22 ... B Material Manufacturing Department, 22a ... B Material Tank, 22b ... B Material Pump, 23 ... C Material Manufacturing Department, 23a ... C material agitator, 23b ... C material pump, 24 ... first line mixer, 25 ... second line mixer, 26 ... injection hose, 26a ... valve, G ... ground, Ga ... permeable layer, SG ... segment, SL ... Segment phosphorus , U1 ... water-permeable back-filling material, U2 ... non-permeable back-filling material

Claims (6)

A backfill layer formed so as to cover the outer peripheral surface of the covering body by injecting and curing a fluidized backfilling material into the gap between the covering body built in the ground and the ground. And
A water permeable part formed in a certain part in the circumferential direction by injection of a water permeable backfill material and having a water passage inside the layer;
A back-filling layer comprising: a water-impermeable portion formed in another portion in the circumferential direction by injection of a water-impermeable backfill material and having no water passage inside the layer.   The backfill layer according to claim 1, wherein the water permeable portion is provided by communicating a plurality of voids formed in a cured material in a cured state.   3. The backfill layer according to claim 1, wherein the non-water-permeable portion is formed on a portion of the outer surface of the lining body that is above the water-permeable portion. The water-permeable backfilling material includes an alkaline curing material that cures over time from a fluid state, a water-absorbing material that dehydrates and shrinks in an alkaline environment, and an expansion agent that reacts in an alkaline environment to generate gas. Including
4. The backfill layer according to claim 1, wherein the water-impermeable backfill material includes a curing material that hardens with time from a fluid state. The water-permeable portion is formed by injecting the water-permeable backfill material mixed with the curing material, the water-absorbing material, and the expansion agent into the gap between the covering body and the ground,
The water-impermeable portion is formed by injecting the water-impermeable backing material containing a curing material for the water-permeable backing material into a gap between the covering body and the ground. The backfill layer of claim 4. An outer peripheral surface of the lining body is injected and cured through a filling port provided in the lining body into a gap between the lining body constructed in the ground and the ground, and then cured. Forming a backfill layer in a state of covering the backfill layer,
After performing a first injection operation of injecting one of the water-permeable backfill material and the non-water-permeable backfill material into the gap between the lining body and the ground through the injection port,
By performing the second injection operation of injecting the other of the water-permeable backfill material and the non-water-permeable backfill material into the gap between the covering body and the ground through the injection port,
One of the water-permeable portion having a water passage inside the layer and the non-water-permeable portion not having the water passage inside the layer includes a circumferential lower end in a gap between the covering body and the ground. Forming the part
A method for forming a backfill layer, wherein the other of the water permeable portion and the non-water permeable portion is formed in the remaining portion including the upper end in the circumferential direction in the gap between the covering body and the ground.

Images