JP5510958B2 - Rock core sampling device - Google Patents

Description

  The present invention relates to a rock core collecting apparatus mainly used for exploring the front of a face during tunnel excavation using jumbo.

  As a geological survey method for constructing underground structures such as tunnels, there is a ground survey method using a rotary percussion drill (for example, Patent Document 1). This method is a geological survey method in which the excavation head fitting attached to the tip of the wire line rod is rotated to dig and the inner tube containing the core is collected by the wire line.

  In addition, a technique for adding a function of draining water from the inner rod has been developed in order to ensure the core in-situ state in the boring core collecting device (for example, Patent Document 2).

  Furthermore, a method of sampling a rock in front of a face by mounting a boring machine on a jumbo drifter has been developed (for example, Patent Document 3).

JP 2001-234686 A JP 2002-38868 A JP 2002-180789 A

  Sampling of the boring core using the conventional rotary percussion requires a dedicated machine and a specialized worker, and cannot be performed on a general-purpose machine used in ordinary tunnel construction. Geological surveys using dedicated machines have a significant impact on the construction period, including not only cost but replacement of machines. In particular, since the geology of the tunnel excavated ground has changed remarkably, it is important to be able to conduct a simple survey each time, and there is a problem that a large-scale temporary facility is required when a dedicated machine is used.

  Further, in core sampling when excavating a large section tunnel, the drilling work by jumbo is congested, and the work efficiency is remarkably lowered.

  Furthermore, in order to secure the core state by rotary percussion drilling water, a method of discharging drilling water that flows back to the inner rod from the connecting pipe connected to the outer rod using centrifugal force has also been proposed. The discharged water after being used in the water flowed between the core and the inner pipe, and there was a problem that it was strongly affected by washing out by the discharged water.

  Furthermore, in the conventional method of mounting a boring machine on a jumbo drifter, since a rock drill is removed and a boring machine is mounted, there is a problem that it becomes impossible to drill a normal blast hole or a lock bolt hole.

  Considering the weight of the boring machine, mounting the boring machine on the jumbo guide cell may cause a heavy load on the machine, leading to a failure of the jumbo and a decrease in durability.

  In view of such a conventional problem, the present invention can be normally mounted on a jumbo drifter used in tunnel construction without any trouble, and in parallel with a drilling operation by a jumbo or a drilling operation. It was made for the purpose of providing a rock core collecting device that can efficiently collect cores between the two, and can be easily constructed as compared with conventional methods.

The feature of the invention according to claim 1 for solving the conventional problems as described above is that a hollow rod is inserted into the guide tube, and a cylindrical outer excavation head fitting is attached to the tip of the guide tube. Provided with a double pipe drilling machine mounted with an inner excavation head metal fitting that can be pushed forward from the inside of the outer excavation head metal fitting at the tip of the hollow rod, the guide pipe has a plurality of circumferentially oriented A slit is formed leaving a peripheral wall portion between the slits, and by cutting the peripheral wall portion between the slits, the guide tube can be divided into a plurality of length directions, and the hollow rod instead of the inner excavation head fitting A rock core collecting pipe that is fixed to the tip of the guide pipe and can move forward from the outer excavation head fitting of the guide pipe, and the rock core collecting pipe has a rear end formed by a rod fixing fitting. Open front-end type sampling tube body with a ring-shaped excavation head fitting fixed at the tip, and inserted into the collection tube body, the tip is detachably connected to the rear end side of the excavation head fitting And a bottomed cylindrical core case whose rear end is closed by the rod fixing bracket, and the rock core sampling tube has a core case outer space between the core case and the sampling tube body. The core case outer space communicates with the hollow rod, and the drill head fitting includes a drill water supply passage leading to the core case outer space, and the inner drill head head bracket is inserted into the outer drill head bracket. The guide pipe is inserted into the drilling hole while performing the double pipe drilling, and then the rock core sampling pipe is inserted in place of the inner drilling head fitting so that the rock core in front of the guide pipe tip can be collected. The rock core sampling device consisting of Te there.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the core case has two symmetrical portions with at least the core case axis in the circumferential direction as a center, and peripheral wall portions at least at both ends. A plurality of slits directed in the length direction are provided, and the circumferential wall portion left in the length direction portion of the slit is cut so that the circumferential direction can be divided into a plurality of portions.

  As described above, in the present invention, a double-pipe drilling machine in which a hollow rod is inserted into a guide tube is used, and instead of the inner excavation head of the hollow rod, from the inside of the outer excavation head fitting at the tip of the guide tube By providing a rock core sampling pipe that can move forward, after drilling to the desired rock core sampling depth with a double pipe drilling machine, the rock core sampling pipe can collect the rock core, so the conventional boring machine Compared with the method of performing core sampling by installing the material on the face, it is easy to construct and is advantageous in terms of cost and construction period.

  In addition, the double-pipe drilling machine can directly apply a casting system for injection-type long steel pipe tips used in wellheads and the like, and does not require a new drilling tool.

  Further, in the present invention, the rock core sampling tube is inserted into the sampling tube main body having an open front end with a rear end closed by a rod fixing metal fitting and a ring-shaped excavation head metal fitting fixed to the tip. The rock core sampling pipe has a bottomed cylindrical core case whose front end side is detachably connected to the rear end side of the excavation head metal fitting, and whose bottom end is closed by the rod fixing metal fitting. A core case outer space is provided between the core case and the sampling tube main body, and the core case outer space is communicated with the hollow rod, and a drilling water supply path is provided in the drill head fitting to the core case outer space. By being provided, the collected rock core is not disturbed by the drilling water, and the sampled rock core can be easily taken out.

Further, in the present invention, the guide tube is formed with a plurality of slits directed in the circumferential direction, leaving the peripheral wall portion between the slits, so that the guide tube is cut by cutting the peripheral wall portion between the slits. Can be divided into a plurality of length directions.

Furthermore, in the present invention, the core case is provided with a plurality of slits oriented in the length direction at least at both ends, leaving peripheral wall portions at two symmetrical positions with respect to at least the core case axis in the circumferential direction. Therefore, the circumferential direction can be divided into a plurality of parts by cutting the peripheral wall portion remaining in the longitudinal direction portion of the slit.

  In addition, rock cores can be sampled using any of the general-purpose machines used in normal tunnel construction, so there is no impact on the extension of the construction period, etc., and it is possible to cope with sudden changes in the ground in advance. , Improve the safety of construction. In addition, physical tests and mechanical tests using natural ground samples can be performed, so it is also possible to predict natural ground behavior during tunnel excavation using analytical methods.

It is a partial abbreviation longitudinal cross-sectional view of the double pipe drilling machine which comprises the rock core extraction apparatus of this invention. It is a partial abbreviation longitudinal cross-sectional view of the rock core collection pipe | tube which comprises the rock core collection apparatus of this invention. It is the partial abbreviation longitudinal cross-sectional view which shifted the cutting angle of the rock core sampling pipe | tube 90 degree | times. It is a front view of the rock core sampling pipe. It is a side view which shows the drilling state which mounted | wore the drill jumbo with the double pipe drilling machine shown in FIG. FIG. 6 is a cross-sectional view showing an extended extension state of the double tube drilling machine shown in FIG. 5. It is sectional drawing which shows the placement state to the natural ground of a rock core collection pipe | tube. It is a side view which shows the slit part of a guide case. It is the sectional view on the AA line in FIG. It is a side view of the core case used for the rock core collection pipe. It is the BB sectional view taken on the line in FIG.

  Next, an embodiment of the rock core collecting device according to the present invention will be described based on the examples shown in the drawings. The rock core collecting apparatus according to the present invention is composed of a double pipe drilling machine A shown in FIG. 1 and a rock core collecting pipe B shown in FIGS. 2 to 4. As shown in FIG. It is mounted on the drill boom 2 and used.

  In FIG. 5, reference numeral 3 is a guide cell supported by 2 on the drill boom of the drill jumbo 1. A rock drill 4 is slidably supported on the guide cell 3. The double-pipe drilling machine A is mounted on the drill head 5 of the rock drill 4.

  As shown in FIG. 1, the double-pipe drilling machine A has a cylindrical guide tube 10 and a hollow rod 11 inserted through the center thereof, and an outer excavation head fitting 12 is attached to the tip of the guide tube 10. While being fixed, an inner excavation head fitting 13 is fixed to the tip of the hollow rod 11.

  The outer excavation head fitting 12 has a cylindrical shape, and a large number of excavation bits 12a, 12a,. The inner excavation head fitting 13 has a cylindrical shape, and a large number of excavation bits 13a, 13a,.

  The inner excavation head metal fitting 13 is inserted into the outer excavation head metal fitting 12 from the guide tube 10 side, and the front end of the inner excavation head metal fitting 13 protrudes forward from the front end of the outer excavation head metal fitting 12 to the inner surface of the outer excavation head metal fitting 12. The fitting mechanism prevents the relative movement in the rotational direction between them, and the outer digging head fitting 12 is pushed out simultaneously by pushing out the inner digging head fitting 13.

  That is, the inner excavation head fitting 13 has a narrow diameter at the front end side and a large diameter at the rear end side, and a step portion 14 is formed in the middle portion. There are a small diameter portion and a large diameter portion corresponding to the outer diameter, a step portion 15 is formed at the boundary, and the step portion 14 of the inner excavation head fitting 13 abuts on the step portion 15 of the outer excavation head fitting 12. The outer drilling head fitting 12 or the inner drilling head fitting 13 is extruded together with the spline 16 that fits between the two and the stepped portions 14 and 15 are fitted to each other when they are in contact with each other. Thus, relative movement in the rotational direction between each other is made impossible.

  As shown in FIGS. 6 and 7, the guide tube 10 is composed of a leading tube 10a integrally having an outer excavation head fitting 12 at the tip and succeeding tubes 10b and 10b sequentially connected to the rear thereof. The side is guided by a guide tube guide 7 provided on the guide cell 4 of the drill jumbo 1.

  The lengths of the leading tube 10a and the trailing tube 10b constituting the guide tube 10 are preferably about 3 to 3.5 m, respectively. In addition, the pipes 10a and 10b are separated by a constant length (in this example, every 1/3 of the total length of each pipe) with an inter-slit peripheral wall portion 17a as shown in FIGS. A slit 17 directed in the circumferential direction is formed, and the peripheral wall portion 17a between the slits is cut by a sander so that a plurality of slits can be divided in the length direction at the slit position. In the figure, reference numeral 18 denotes a joint between the leading pipe 10a and the succeeding pipe 10b and between the succeeding pipes 10b, and a screw-in type or a one-touch type can be used as this joint.

  The hollow rod 11 is composed of a leading rod 11a integrally having an inner excavation head fitting 13 at the tip and succeeding rods 11b and 11b sequentially connected behind the leading rod 11a, and the rear end side is a guide cell 3 of the drill jumbo 1. It is fixed to the drill head 5 of the rock drill 4 provided above. A water supply hole 5 a is formed in the drill head 5, and water for washing excavation waste is supplied into the hollow rod 11, and this water is supplied to the excavation face through a water supply hole 13 b formed in the inner excavation head fitting 13. It is like that. The lengths of the leading rod 11a and the succeeding rod 11b are about 3 to 3.5 m like the guide tube.

  As shown in FIGS. 2 to 4, the rock core sampling tube B is composed of a bottomed cylindrical sampling tube body 20 having an open front end side, and a core case 21 accommodated therein.

  The sampling tube main body 20 includes a trunk cylindrical tube 22, a cylindrical excavation head fitting 23 fixed to the front end thereof, and a rod fixing fitting 24 fixed to the rear end of the trunk cylindrical tube 22 in a closed state. It consists of and. A number of excavation bits 23 a protrude from the front end of the excavation head fitting 23.

  The sampling tube main body 20 is formed such that the outer diameters of the trunk cylindrical tube 22, the excavation head metal fitting 23 at the front end thereof, and the rod fixing metal fitting 24 at the rear end thereof are substantially the same diameter, and excavated in the front end of the trunk cylindrical tube 22. A male screw on the outer periphery of the head metal fitting 23 is screwed, and a male screw on the outer circumference of the rod fixing metal fitting 24 is screwed into the rear end.

  The core case 21 is a cylindrical tube having an outer diameter that is smaller than the inner diameter of the trunk cylindrical tube 22 of the sampling tube main body 20, and a gap 29 is formed therebetween. The front end of the core case 21 is fitted in a core case fitting enlarged diameter portion 25 formed on the inner periphery of the rear end portion of the excavation head fitting 23 of the sampling tube main body 20. In the figure, reference numeral 25 a denotes a spacer for fitting the core case 21 in a concentric arrangement with the enlarged diameter portion 25.

  On the other hand, a small-diameter portion 26 smaller than the inner diameter of the body cylindrical tube 22 is formed at the front end of the rod fixing bracket 24, and a smaller-diameter core case fitting portion 27 is formed on the outer periphery of the tip portion. The rear end of the core case 21 is fitted to the outer periphery of the portion 27.

  The core case 21 can be taken out and inserted into the sampling tube main body 20 by removing the excavation head fitting 23 or the rod fixing fitting 24 from the trunk cylindrical tube 22. The length of the core case 21 is made of a steel pipe or acrylic resin pipe having a length of about 1 m, and a slit 28 for division is formed in the length direction.

  As shown in FIGS. 10 and 11, the slits 28 are formed at symmetrical positions every 180 degrees on the circumference in the length direction of the core case, and both ends of the core case and 1/3 of the total length thereof. It is formed at each position, leaving the peripheral wall portion 28a left in the length direction portion of the slit. The core case can be divided into two semi-cylindrical shapes by cutting the peripheral wall portion 28a between the slits with a sander.

  The rod fixing bracket 24 is formed at its rear end with a female screw hole 30 into which the tip of the hollow rod 11 of the double tube drilling machine A described above is screwed, and the inner excavation head fitting 13 is replaced with the hollow rod 11. It can be installed.

  As shown in FIGS. 2 to 4, the sampling pipe main body 20 is formed with a drilling water supply path through which drilling water is discharged from the tip of the drilling head fitting 24 at the front end. This drilling water supply path includes a water passage hole 31 communicating with the outer periphery of the small diameter portion 26 from the center of the female screw hole 30 of the rod fixing bracket 24, a gap 29 between the trunk cylindrical tube 22 and the core case 21, and this gap 29 The drilling head metal 23 is provided with a water supply nozzle 32 penetrating and opening through the wall thickness of the drilling head fitting 23 so that the drilling water is supplied between the drilling bits 23 by supplying water through the hollow rod 11. .

  For the excavation head fitting 23, various types such as a button excavation head fitting, a single-edged excavation head fitting, and a double-edged excavation head fitting are used in accordance with the natural conditions. By selecting and using these, it is possible to respond to sudden changes from soft ground to hard rock ground, and from hard ground to soft ground, and it is possible to sample the core without being affected by the softness of the ground. it can.

  When using the rock core collecting apparatus configured as described above, the double-pipe drilling machine A is mounted on the guide cell 3 supported by the drill boom 2 of the drill jumbo 1 as shown in FIG. In this mounting, the guide rod 10 is supported on the guide cell 3, and the proximal end side of the hollow rod 11 is fixed to the drill head 5 of the rock drill 4.

  In this state, the guide cell 3 is set on the face mirror part 33, the rock drill 4 is operated, the drilling water is supplied from the hollow rod 11, and the guide tube 10 is inserted into the drilling hole. In this operation, the succeeding tube 10b and the succeeding rod 11b are joined to make a hole to a desired depth, and the guide tube 10 is inserted therein.

  After drilling with the double pipe drilling machine A to a desired depth, that is, a desired rock core sampling depth, a rock core sampling operation is performed. In this sampling operation, the guide tube 10 is left in the drilling hole, and the inner excavation head fitting 13 is extracted together with the hollow rod 11. A rock core sampling tube B is fixed to the tip of the hollow rod 11 instead of the metal fitting 13, and the succeeding rod 11b is inserted into the guide tube 10 while being added. With the excavation head fitting 23 reaching the innermost part of the drilling hole, the hollow rod 11 is fixed to the drill head 5 of the rock drill 4 and the rock drill 4 is operated while supplying drilling water from the hollow rod 11. As shown in FIG. 7, the rock core sampling tube B is placed in the ground in front of the front end of the guide tube 10, and the rock core cut out in a cylindrical shape by the excavation head fitting 13 is accommodated in the core case 21. .

  After collecting the rock core up to the longest core case length in this way, the rock core collecting tube B is pulled out together with the hollow rod 11, the core case 21 is taken out from the rock core collecting tube B, and the internal rock core is taken out.

A Double pipe drilling machine B Rock core sampling pipe 1 Drill jumbo 2 Drill boom 3 Guide cell 4 Rock drill 5 Drill head 5a Water feed hole 10 Guide pipe 10a Lead pipe 10b Subsequent pipe 11 Hollow rod 11a Lead rod 11b Subsequent rod 12 Outer drilling head fitting 12a Drilling bit 13 Inner drilling head fitting 13a Drilling bit 13b Water supply hole 14 Step portion 15 Step portion 17 Slit 17a Slit peripheral wall portion 18 Joint 20 Sampling pipe body 21 Core case 22 Trunk cylindrical tube 23 Drilling head fitting 23a Drilling bit 24 Rod fixing bracket 25 Wide diameter portion 26 Small diameter portion 27 Core case fitting portion 28 Slit 28a Peripheral wall portion 29 Clearance 30 Female screw hole 31 Water passage hole 32 Water supply nozzle 33 Face mirror portion

Claims (2)

An inner excavation head in which a hollow rod is inserted into the guide tube, a cylindrical outer excavation head fitting is attached to the tip of the guide tube, and the tip of the hollow rod can be pushed forward from the inside of the outer excavation head fitting. It has a double-pipe drilling machine equipped with metal fittings,
In the guide tube, a plurality of slits directed in the circumferential direction are formed leaving the peripheral wall portion between the slits, and the guide tube can be divided into a plurality of length directions by cutting the peripheral wall portion between the slits. And
A rock core sampling pipe that is fixed to the tip of the hollow rod instead of the inner drilling head fitting and can move forward from within the outer drilling head fitting of the guide pipe,
The rock core sampling tube has a rear end closed by a rod fixing bracket, a front end open type sampling tube main body having a ring-shaped excavation head metal fixture fixed to the tip, and the tip is inserted into the sampling tube main body. A bottomed cylindrical core case that is detachably connected to the rear end side of the head metal fitting and whose rear end is closed by the rod fixing metal fitting,
The rock core collecting pipe includes a core case outer space between the core case and the collecting pipe main body, and the core case outer space communicates with the hollow rod. It has a drilling water supply channel that leads to the gap outside the case,
Inserting the inner drilling head fitting into the outer drilling head fitting and drilling a double pipe while inserting the guide pipe into the drilling hole, and then inserting the rock core sampling pipe in place of the inner drilling head fitting. A rock core collecting device that can collect the rock core in front of the tip of the guide tube. The core case is provided with a plurality of slits oriented in the length direction at least at both end portions, with the circumferential wall portions at least at both ends in the circumferential direction, and having a length in the length direction. The rock core collecting device according to claim 1, wherein the circumferential direction is cut so as to be divided into a plurality of circumferential directions.

Images