JP7308797B2 - Soil Sampling Jig and Soil Sampling Method in Ground around Shield Tunnel - Google Patents

Description

TECHNICAL FIELD The present invention relates to a technique for collecting soil samples from ground around a shield tunnel.

Construction work to connect shield tunnels in the ground without excavation generally involves cutting out part of the shield tunnel. Auxiliary construction method for As auxiliary construction methods, the chemical injection method of injecting a chemical solution into the ground, the ground improvement method of partially improving the ground, the freezing method of freezing the ground, and the like are adopted. These auxiliary construction methods are designed based on the results of in-situ tests carried out inside the borehole by boring from the ground surface and laboratory tests using soil samples taken from the same borehole. However, it is often difficult to obtain a sufficient amount of local soil information, which is required ex post facto for detailed examinations, each time, due to restrictions on construction work, etc., only with such an approach from the ground surface.
Patent Document 1 discloses a screw-type earth removing device in which a pressure chamber is formed between a cutter head rotatably supported by a partition wall of a shield body and the partition wall, and excavated earth and sand taken into the pressure chamber is discharged. Disclosed is an apparatus for sampling excavated earth and sand in an earth pressure type shield machine equipped with
Further, Patent Document 2 discloses a shield machine having a cutter face plate arranged at the front end portion in the direction of tunnel excavation and a shield partition wall arranged behind the cutter face plate and partitioning the cutter chamber between the cutter face plate and the cutter face plate. An apparatus for sampling earth and sand in front of a mountain is disclosed.

JP-A-2004-68250 JP 2013-256843 A

The invention described in Patent Document 1 is a device and method for collecting excavated earth and sand taken into a cutter chamber of a shield excavator, and analyzes the collected earth and sand to reflect it in face stability. It is used for the purpose. On the other hand, the information necessary for the design of the auxiliary construction method is the information obtained from undisturbed soil samples collected from the ground around the shield tunnel. soil and sand) are not covered. On the other hand, Patent Document 2 is based on the premise of collecting earth and sand in front of the face during shield excavation, and cannot collect from an unplanned range after shield excavation.

An object of the present invention is to safely collect an undisturbed soil sample using the grout holes at any position from the ground around the shield tunnel where the grout holes are provided, even after the shield tunnel is constructed. It is therefore an object of the present invention to provide a soil sampling jig and a soil sampling method capable of restoring the current state after sampling the soil.

In order to achieve the above object, one aspect of the soil sampling jig for the ground around the shield tunnel according to the present invention is a soil sampling jig for the ground around the shield tunnel provided with a grout hole, wherein the jig is screwed into the grout hole. and a sleeve connected to the socket, wherein the sleeve, the socket and the grout hole are connected so that a boring rod can be inserted therethrough, the sleeve is connected to the packer, the packer and the socket and a sluice valve between the sockets, wherein the sockets are non-rotatably fixed to the inner wall surface of the shield tunnel near the grout holes.
Here, grout holes may be provided in advance at the time of manufacturing the segments that constitute the shield tunnel, or may be installed at an arbitrary location after the construction of the shield tunnel or at the time of construction of the shield tunnel.

Since the socket, which is one aspect of the present invention, is non-rotatably fixed to the inner wall surface of the shield tunnel near the grout hole, the entire soil sampling jig is supplied from the frictional resistance with the packer accompanying the rotation of the boring rod. You can avoid turning around. Since the socket is screwed into the grout hole, if the socket, which constitutes part of the soil sampling jig, is rotated in the direction of screwing into the grout hole, the screw thread may be destroyed or the socket may be removed due to excessive engagement. Conversely, if the socket rotates in the loosening direction, the socket may come off the grout hole and groundwater may enter the pit.

In another aspect of the jig for sampling soil around the shield tunnel according to the present invention, the sleeve further comprises a mud discharge valve between the packer and the socket.

According to this aspect, the sleeve is further provided with a mud discharge valve between the packer and the socket, so when drilling a part of the shield tunnel accompanied by drilling water, the mud water generated along with drilling is quickly discharged. can be discharged to In addition, by controlling the opening and closing of the valve, it is possible to adjust the amount of groundwater infiltration.

Further, in another aspect of the jig for sampling soil in the ground around the shield tunnel according to the present invention, the shield tunnel is formed of a plurality of steel segments including longitudinal ribs arranged in the axial direction of the shield tunnel, The socket is fixed to the longitudinal rib.

According to this aspect, since the socket can be fixed to the vertical ribs constituting the steel segment by means of detachable means such as welding, a vise, or bolts and nuts, the state can be restored to almost the current state by removing the socket. .

In another aspect of the jig for sampling soil in the ground surrounding a shield tunnel according to the present invention, the inner wall surface of the shield tunnel is formed of a plurality of concrete segments coated with concrete, and the socket is formed on the inner wall surface of the shield tunnel. is fixed with a plurality of anchors.

According to this aspect, since the socket is fixed to the concrete inner wall surface of the concrete segment with a plurality of anchors, there is no structural problem, and by removing the socket, the state can be restored to almost the current state.

One aspect of the method for collecting a soil sample from the ground around the shield tunnel according to the present invention is a method for collecting a soil sample from the ground around the shield tunnel provided with a grout hole using the above-mentioned sampling jig, wherein the above-mentioned a socket screwing step of screwing a socket; a socket fixing step of non-rotatably fixing the socket to the inner wall surface of the shield tunnel; a sleeve connecting step of connecting a sleeve to the socket; A drilling step of inserting a rod to drill a part of the shield tunnel from the grout hole, and a sampling step of inserting a boring rod for sampling into the sleeve and sampling the ground around the shield tunnel. It is characterized by

Since there is a socket fixing step of fixing the socket to the inner wall surface of the shield tunnel so that it cannot rotate, which is one aspect of the present invention, the entire soil sampling jig rotates together due to the frictional resistance with the packer accompanying the rotation of the boring rod. can be avoided. Since the socket is screwed into the grout hole, if the socket, which constitutes part of the soil sampling jig, is rotated in the direction of screwing into the grout hole, the screw thread may be destroyed or it may not be possible to remove it. On the other hand, if it rotates in the loosening direction, the socket may come off the grout hole and groundwater may enter the pit.

Further, in another aspect of the soil sampling method in the ground around the shield tunnel according to the present invention, a freezing step of inserting a freezing tube into the sleeve to freeze the surrounding ground near the grout hole; and a soil sampling jig removing step of removing the sampling jig by removing it from the inner wall surface of the shield tunnel.

According to this aspect, since it has a freezing step of inserting the freezing pipe into the sleeve and freezing the surrounding ground near the grout hole, while the surrounding ground is frozen, while suppressing the infiltration of groundwater, Sockets can be safely removed from grout holes and inner walls of shield tunnels.

According to the soil sampling jig for the ground around the shield tunnel and the soil sampling method using the jig for sampling soil of the present invention, the grout holes are used from the ground around the shield tunnel provided with the grout holes. It is to collect undisturbed soil samples safely by using the method, and it is possible to restore the existing condition after collecting the soil samples.

1 is a bird's-eye view of an inner wall surface of a shield tunnel made of steel segments according to an embodiment of the present invention; FIG. FIG. 4 is a cross-sectional view of a grout hole associated with a concrete segment and a steel segment according to an embodiment of the invention; FIG. 2 is a cross-sectional view and a plan view (viewed from arrow AA) of a socket that constitutes a soil sampling jig according to an embodiment of the present invention; 1 is a cross-sectional view of a soil sampling jig according to an embodiment of the present invention; FIG. FIG. 4 is a cross-sectional view of construction for removing a hole check valve, a skin plate, and a back-filling material in a grout hole, which hinder soil sampling using the soil sampling jig according to the embodiment of the present invention. FIG. 2 is a construction cross-sectional view showing a soil sampling state in the soil sampling method using the soil sampling jig according to the embodiment of the present invention. FIG. 2 is a construction cross-sectional view showing a freezing situation in which the ground around the shield tunnel is frozen in the soil sampling method using the soil sampling jig according to the embodiment of the present invention. FIG. 2 is a construction cross-sectional view showing how the soil sampling jig is removed from the grout hole and the inner wall surface of the shield tunnel in the soil sampling method using the soil sampling jig according to the embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, the soil sampling jig|tool in the ground around the shield tunnel which concerns on embodiment of this invention, and the soil sampling method using the soil sampling jig|tool are demonstrated, referring attached drawing. In addition, in this specification and the drawings, substantially the same components are denoted by the same reference numerals, thereby omitting redundant explanations.

First, with reference to FIGS. 1 and 2, the grout holes of the segments forming the shield tunnel will be described. FIG. 1 is an overhead view of the inner wall surface of a shield tunnel made of steel segments according to an embodiment of the present invention, and FIG. 2 is a concrete segment and grout holes associated with the steel segments according to an embodiment of the present invention. is a cross-sectional view of.
In general, a plurality of segments 1, 1, . . The segment 1 is mainly composed of a steel segment 11, a concrete segment 12 (RC segment or a composite segment in which concrete is filled in a steel shell), and the like.

FIG. 1 is a photograph of the inner wall surface of the steel segment 11. One piece of the steel segment 11 consists of two opposing arc plate-shaped main girders 111, 111 and a rectangular plate-shaped joint plate 113, A frame made of 113 and a film-like skin plate 114 on the ground side of the frame are integrally welded to form a box, and between the joint plates 113 and 113 and parallel to the joint plates 113 and 113 , a plurality of vertical ribs 112, 112, . By connecting a plurality of steel segments 11, 11 ..., the main girders 111, 111 ... are connected in a ring shape, and the vertical ribs 112, 112 ... are connected in the axial direction of the shield tunnel ST. The steel segments 11, 11 adjacent to each other in the ring direction have their joint plates 113, 113 facing each other, and the adjacent rings have their main girders 111, 111 facing each other facing each other. spliced. A grout hole 2 is provided approximately in the center of each steel segment 11 . The shield tunnel ST fills a gap (generally referred to as a tail void) between the shield tunnel ST and its surrounding ground during excavation by a shield machine (not shown) by backfilling. Backfilling can be broadly divided into two types: a simultaneous backfilling injection method in which the material is injected from behind the shield machine (not shown) at the same time as the shield machine is digging, and an immediate injection method in which the material is injected directly from the grout hole 2 . In the former case, the grout hole 2 is not necessary, but in preparation for the case where insufficient injection occurs due to mechanical trouble, generally one grout hole 2 can be provided for one piece of segment 1. many.

FIG. 2(a) shows a concrete segment 12, and (b) and (c) of FIG.
The grout hole 2 consists of the grout hole wall 21, the grout cap 22, and the hole check valve 23 from (a) of the same figure. The grout hole wall 21 is made of a steel cylindrical pipe that penetrates the inside and outside of the concrete segment 12, and is designed to be watertight with the concrete that constitutes the concrete segment 12 in order to withstand the groundwater pressure around the outer circumference of the shield tunnel ST. embedded in one piece. A screw portion is formed on the inner surface of the grout hole wall 21 on the inner surface side of the shield tunnel ST so that the grout cap 22 can be screwed thereon. An O-ring (not shown) is fitted to the lower surface of the hooking portion of the grout cap 22 . When the grout cap 22 is screwed onto the grout hole wall 21 , the O-ring is positioned between the grout cap 22 and the grout hole wall 21 . It exerts a packing effect that can be pressed against the underground water pressure. A hole check valve 23 is screwed to the grout hole wall 21 so as to ensure water stopping performance so that groundwater does not spout when the grout cap 22 is removed.

4B, the grout hole wall 21 in the steel segment 11 is welded integrally around the opening of the skin plate 114, but the grout hole 2 in the concrete segment 12 and its basic structure are different. The basic configuration is the same.

On the other hand, (c) of the same figure also shows a cross-sectional view of the grout hole 2 in the steel segment 11, but the skin plate 114 does not have an opening communicating with the grout hole 2 in advance. ) case. Since the skin plate 114 has no opening, the hole check valve 23 is not provided in advance in the grout hole wall 21, so that the structure is simpler and the cost is lower than in FIG. This type is often adopted for the steel segments 11 to which the above-mentioned simultaneous backfilling injection method is applied. It is based on the concept of secondary injection. In this case, the skin plate 114 is machine drilled during injection.
In addition to the case where the grout holes are provided in advance when the segments constituting the shield tunnel are manufactured, the cases where the grout holes are installed at arbitrary places after the construction of the shield tunnel or during the construction of the shield tunnel are also included. For example, the steel segment 11 can be welded to the skin plate 114 .

[Jig for sampling soil around the shield tunnel]
Next, with reference to FIGS. 3 and 4, a soil sampling jig for the ground around the shield tunnel according to the embodiment will be described. FIG. 3 is a cross-sectional view and a plan view (viewed from arrow AA) of a socket that constitutes a soil sampling jig according to an embodiment of the present invention, and FIG. 4 is a soil sampling according to an embodiment of the present invention. It is a sectional view of a jig.
Henceforth, the segment 1 is a steel segment 11 and the grout hole 2 is of the type shown in FIG. 2(c).

The soil sampling jig J comprises a socket 3 screwed into the grout hole 2 and a sleeve 4 connected to the socket 3. The sleeve 4, the socket 3 and the grout hole 2 allow the boring rod L to pass through. The sleeve 4 is provided with a packer 44 and a gate valve 42 between the packer 44 and the socket 3 , and the socket 3 is non-rotatably fixed to the inner wall surface of the shield tunnel ST near the grout hole 2 .
3 shows the socket 3 of the soil sampling jig J, and FIG. 4 shows the entire soil sampling jig J in which the sleeve 4 is connected to the socket 3. As shown in FIG.

3, the socket 3 comprises a connecting pipe 31 that can be screwed into the grout hole wall 21, a sleeve leading pipe 32 that can be connected to the connecting pipe 31, and a rotation preventing member 33 that can be connected to the sleeve leading pipe 32. As shown in FIG.
A cylindrical connecting pipe 31 having a hooking portion has a threaded portion that can be screwed into the grout hole wall 21 after the grout cap 22 has been removed, and a is fitted with an O-ring (not shown), and when the connecting pipe 31 is screwed to the grout hole wall 21, the O-ring is pressed between the connecting pipe 31 and the grout hole wall 21 to produce a packing effect capable of resisting groundwater pressure. Demonstrate.
Next, in order to connect with the sleeve 4 which will be described later, the head of the sleeve tip pipe 32 has an annular flange portion having a plurality of through holes. The sleeve tip pipe 32 and the anti-rotation member 33 are integrally connected with bolts and nuts, and then the anti-rotation member 33 is laid horizontally across a plurality of through holes provided in the vertical ribs 112, 112 adjacent to the grout hole 2. and fix with bolts and nuts. At this time, since the end portion of the sleeve tip conduit 32 is adjusted to contact the upper surface of the hooking portion of the connecting pipe 31, both members are integrated by fillet welding the outer periphery of this contact portion. As a result, the connection pipe 31 can prevent the entire soil sampling jig J from co-rotating due to frictional resistance between the connecting pipe 31 and the packer 44 due to the rotation of the boring rod L, which will be described later. Since the socket 3 is screwed into the grout hole 2 via the connection pipe 31, when the socket 3, which constitutes a part of the soil sampling jig J, rotates together in the direction of screwing into the grout hole 2, the connection pipe 31 and the screw threads of the grout hole wall 21 may be destroyed, or it may become impossible to remove due to excessive engagement. because it can penetrate into
The segment 1 of this embodiment is a steel segment 11, but it may be a concrete segment 12. In this case, a plurality of anchors are driven into the concrete surface constituting the concrete segment 12, and these anchors are attached. The socket 3 is fixed through the
Also, although the socket 3 is configured from separate members consisting of the connection tube 31, the sleeve tip tube 32, and the anti-rotation member 33, it may be an integral member. In this case, the connection with the longitudinal ribs 112, 112 adjacent to the grout hole 2 may be crimped or welded by a vise, and is not limited to the embodiment as long as the socket 3 does not rotate.

4, the sleeve 4 is composed of a sleeve main pipe 41, a gate valve 42, a mud discharge valve 43 and a packer 44. As shown in FIG.
At one end of the sleeve main pipe 41 made of a cylindrical pipe, there is an annular flange portion having a plurality of through holes. Connect them together with bolts and nuts through the holes. In order to secure a predetermined water stop performance, an annular plate-like packing (not shown) is interposed between the two flange portions.
A packer 44 is provided at the mouth of the sleeve main pipe 41 on the other end side, and a gate valve 42 and a mud discharge valve 43 are provided so as to communicate with the sleeve main pipe 41 . The packer 44 exerts a waterproofing effect to prevent groundwater from flowing out when a boring rod L, which will be described later, is inserted into the surrounding ground G from the mouth of the sleeve main pipe 41 . The sluice valve 42 can block the passage of the sleeve main pipe 41, and includes a gate valve, a ball valve, and the like. Further, the mud discharge valve 43 is a valve for quickly discharging the mud to the outside of the sleeve main pipe 41 when the drilling work by the boring machine B, which will be described later, involves water supply. Since the packer 44, the gate valve 42, and the sludge discharge valve 43 assumed in this embodiment are all general-purpose products that are generally used, detailed descriptions of their mechanisms and structures are omitted here. , these forms are not limited to this embodiment.

[Method for collecting soil samples from the ground around the shield tunnel]
5 and 6, a soil sampling method in the ground around the shield tunnel according to the embodiment will be described. FIG. 5 is a construction cross-sectional view for removing the hole check valve, skin plate, and back-filling material in the grout hole that hinder soil sampling using the soil sampling jig according to the embodiment of the present invention. FIG. 6 is a construction cross-sectional view showing a soil sampling state in a soil sampling method using a soil sampling jig according to an embodiment of the present invention.
This embodiment is a method for sampling the surrounding ground G of a shield tunnel ST having a grout hole 2 using the above-described soil sampling jig J, and is a socket screwing step of screwing a socket 3 into the grout hole 2. a socket fixing step of fixing the socket 3 to the inner wall surface of the shield tunnel ST so as not to rotate; a sleeve connecting step of connecting the sleeve 4 to the socket 3; A drilling step of drilling a part of the shield tunnel ST from 2 and a sampling step of inserting a boring rod L for sampling into the sleeve 4 and taking a sample S of the surrounding ground G of the shield tunnel ST.

As described above, the socket 3 is fixed to the vertical ribs 112, 112 of the steel segment 11 that constitutes the inner wall surface of the shield tunnel ST adjacent to the grout hole 2 to be sampled (socket fixing process). After the socket 3 is screwed (socket screwing step), the soil sampling jig J is used in which the sleeve 4 is connected to the socket 3 (sleeve connecting step).
As shown in FIG. 5A, a boring rod L having a metal crown M for drilling holes is inserted at its tip using a boring machine B from the mouth side of the sleeve 4 where the packer 44 is provided.
From (b) of the figure, the back-filling injection material F is drilled together with the skin plate 114 (drilling step). During drilling, water is supplied from the inside of the boring rod L, and the sludge discharge valve 43 discharges into the pit while adjusting the valve opening appropriately so that the inside of the soil sampling jig J etc. does not become abnormally high pressure. do the mud
In addition, although this example shows a form involving water supply (drilling water), it does not exclude waterless drilling.
In this embodiment, the segment 1 is a steel segment 11, and the grout hole 2 is of the type shown in FIG. 2(c). The form of (a) is not excluded, and the hole check valve 23 shown in FIGS. including cases where
From FIG. 5(c), while the boring rod L is hooked on the packer 44, the sludge discharge valve 43 and the gate valve 42 are closed to shut off the underground water from the pit. The boring rod L is pulled out from the soil sampling jig J, and the drilled material interposed in the boring rod L including the metal crown M is recovered.

As shown in FIG. 6A, a boring rod L having a core bit C for collecting soil samples is inserted at the tip thereof using a boring machine B from the mouth side of the sleeve 4 where the packer 44 is provided. After confirming that the boring rod L is hooked to the packer 44, the gate valve 42 is opened (while the mud discharge valve 43 remains closed).
As shown in (b) of the figure, the core bit C is penetrated into the surrounding ground G in consideration of the length of the sample S required for the test, and the sample S is accommodated in the boring rod L. At this time, since there is a possibility of disturbing the sample S, water is not fed in principle.
As shown in (c) of the figure, while the boring rod L is hooked on the packer 44, the gate valve 42 is closed to shut off the underground water from the pit. The boring rod L is pulled out from the soil sampling jig J, and the sample S stored in the boring rod L is extracted (sample sampling step).
It should be noted that this embodiment does not exclude the sampling of the sample S from the surrounding ground G including the back-filling injection material F, or omitting the drilling step and performing drilling and sampling in the same step. . However, if the length of waterless drilling becomes long, or if the back-filling material F, drilling debris of the skin plate 114, etc. remain with the sampling of the sample S, adverse effects such as disturbing the sample S will occur. Therefore, it is desirable to separate the drilling process and the sampling process as in this embodiment.

[Restoration method for the ground around the shield tunnel after collecting soil samples]
Next, referring to FIGS. 7 and 8, a description will be given of a method for restoring the present condition after taking a soil sample in the ground around the shield tunnel according to the embodiment. FIG. 7 is a construction cross-sectional view showing a freezing situation in which the ground around the shield tunnel is frozen in the soil sampling method using the soil sampling jig according to the embodiment of the present invention, and FIG. FIG. 4 is a construction cross-sectional view showing how the soil sampling jig is removed from the grout hole and the inner wall surface of the shield tunnel in the soil sampling method using the soil sampling jig according to the embodiment.
This embodiment includes a freezing process of inserting a freezing tube into the sleeve 4 to freeze the surrounding ground G near the grout hole 2, and removing the socket 3 from the grout hole 2 and the inner wall surface of the shield tunnel ST to collect a soil sample. A soil sampling jig removal step of removing the jig J is further included.

As shown in FIG. 7A, the outer frozen tube O is inserted using a boring machine B from the mouth side of the sleeve 4 where the packer 44 is provided. After confirming that the frozen outer tube O is hooked to the packer 44, the sluice valve 42 (while the mud discharge valve 43 remains closed) is opened, and the frozen outer tube O is inserted to a predetermined position. At this time, the frozen inner tube I may be provided in the frozen outer tube O in advance, or may be inserted later.
Next, from (b) of the same figure, brine (coolant) is flowed from the mouth of the frozen inner tube I, and from the tip of the frozen inner tube I through the gap between the frozen inner tube I and the frozen outer tube O, Circulate the brine (freezing step). As a result, the surroundings of the frozen outer tube O are cooled, and the groundwater (interval water) in the ground is frozen in the shape of annual rings around the frozen outer tube O, creating the frozen area FA, and the soil sampling jig described later. When J is removed, it is possible to prevent the infiltration of groundwater into the shield tunnel ST tunnel.
From (c) of the figure, it can be confirmed that water is completely stopped by the frozen area FA by opening the mud discharge valve 43 while the frozen outer tube O is hung on the packer 44 .
In addition, when the hole wall is collapsed after sample collection, the frozen tube is placed while re-drilling with a drilling type freezing tube.

From (a) of FIG. 8, after confirming that groundwater is blocked by creating the frozen area FA, the soil sampling jig J is removed from the inner wall surface (segment 1 or steel segment 11) of the shield tunnel ST. Remove (soil sampling jig removal step).
From (b) of the figure, the grout cap 22 is screwed onto the grout hole wall 21 for restoration. If necessary, the hole check valve 23 may be inserted into the grout hole wall 21 if it is assumed that the gaps formed by drilling or sampling are filled with a filler, or if the grout cap 22 is removed afterward. It is better to wear it on the

According to the soil sampling jig for the ground around the shield tunnel and the soil sampling method using the soil sampling jig of the present embodiment, the socket is non-rotatably fixed to the inner wall surface of the shield tunnel near the grout hole. Therefore, it is possible to prevent the entire soil sampling jig from co-rotating due to the frictional resistance between the boring rod and the packer due to the rotation of the boring rod. Since the socket is screwed into the grout hole, if the socket, which constitutes part of the soil sampling jig, is rotated in the direction of screwing into the grout hole, the screw thread may be destroyed or the socket may be removed due to excessive engagement. Conversely, if the socket rotates in the loosening direction, the socket may come off the grout hole and groundwater may enter the pit.
Since the sleeve is further equipped with a mud discharge valve between the packer and the socket, when drilling a part of the shield tunnel with drilling water, the mud water generated by drilling can be quickly drained. can. In addition, by controlling the opening and closing of the valve, it is possible to adjust the amount of groundwater infiltration.
Furthermore, since the sockets can be fixed to the vertical ribs that make up the steel segments by means of detachable means such as welding, vices, bolts and nuts, the sockets can be removed to restore almost the current state. Even concrete segments can be restored in the same way by fixing them to the concrete inner wall surface with a plurality of anchors.

According to the soil sampling method using the soil sampling jig in the ground around the shield tunnel of the present embodiment, since it has a socket fixing step of fixing the socket to the inner wall surface of the shield tunnel so that it cannot rotate, it is possible to rotate the boring rod. It is possible to prevent the entire soil sampling jig from co-rotating due to frictional resistance with the accompanying packer.
In addition, since there is a freezing step of inserting a freezing pipe into the sleeve and freezing the surrounding ground near the grout hole, if the surrounding ground is frozen, the socket can be removed from the grout hole while suppressing the infiltration of groundwater. and can be safely removed from the inner wall of the shield tunnel.

It should be noted that other embodiments may be possible in which other components are combined with the configurations listed in the above embodiments, and the present invention is not limited to the configurations shown here. .
Regarding this point, it is possible to change without departing from the gist of the present invention, and it can be determined appropriately according to the application form.

ST Shield tunnel G Surrounding ground F Back-filling injection material J Soil sampling jig B Boring machine L Boring rod M Metal crown C Core bit S Specimen O Frozen outer tube I Frozen inner tube FA Frozen area 1 Segment 11 Steel segment 111 Main girder 112 Vertical rib 113 Joint plate 114 Skin plate 12 Concrete segment 2 Grout hole 21 Grout hole wall 22 Grout cap 23 Hole check valve 3 Socket 31 Connecting pipe 32 Sleeve tip conduit 33 Anti-rotation member 4 Sleeve 41 Sleeve main pipe 42 Gate valve 43 sludge discharge valve 44 packer

Claims (6)

A sampling jig for ground around a shield tunnel provided with grout holes,
a socket screwed into the grout hole;
a sleeve connected to the socket;
The sleeve, the socket, and the grout hole are connected so that a boring rod can be inserted therethrough,
the sleeve with a packer;
a gate valve between the packer and the socket;
A soil sampling jig for ground surrounding a shield tunnel, wherein the socket is non-rotatably fixed to the inner wall surface of the shield tunnel near the grout hole. 2. The jig for sampling soil around the shield tunnel according to claim 1, wherein the sleeve further comprises a mud discharge valve between the packer and the socket. The shield tunnel is formed of a plurality of steel segments including longitudinal ribs arranged in the axial direction of the shield tunnel,
3. The jig for sampling soil around the shield tunnel according to claim 1, wherein the socket is fixed to the longitudinal rib. The inner wall surface of the shield tunnel is formed of a plurality of concrete segments covered with concrete,
3. The jig for sampling soil around the shield tunnel according to claim 1, wherein the socket is fixed to the inner wall surface with a plurality of anchors. A soil sampling method for ground around a shield tunnel provided with grout holes using the soil sampling jig according to any one of claims 1 to 4,
a socket screwing step of screwing the socket into the grout hole;
a socket fixing step of non-rotatably fixing the socket to the inner wall surface of the shield tunnel;
a sleeve connecting step of connecting a sleeve to the socket;
a drilling step of inserting a boring rod for drilling into the sleeve and drilling a part of the shield tunnel from the grout hole;
and a sampling step of inserting a boring rod for sampling into the sleeve to collect a sample of the ground around the shield tunnel. A freezing step of inserting a freezing pipe into the sleeve to freeze the surrounding ground near the grout hole;
6. The shield according to claim 5, further comprising a soil sampling jig removing step of removing the soil sampling jig by removing the socket from the grout hole and the inner wall surface of the shield tunnel. Soil sampling method in the ground around the tunnel.

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