JP6664649B1 - Standard penetration test method and equipment - Google Patents

Abstract

A work load of a standard penetration test is reduced. A standard penetration test apparatus 1 is provided so as to be able to withdraw from a measurement position for obtaining an N value, and an excavator D holds or releases a rod R connected to a lower portion thereof, and at the measurement position, An excavation mechanism 3 for excavating a hole in the ground with an excavation tool D by lowering the rod R held while rotating it, and a rod leader standing upright beside the rod R held or released by the excavation mechanism 3. 40 and a leader 40 for a rod, which is provided so as to be movable, holds or releases the rod R so that the rod R held or released by the excavation mechanism 3 penetrates, and holds the held rod R. A rod chuck 41 that moves upward and pulls up the excavation tool D to the ground, and a rod chuck 41 that is provided so as to be retractable from the measurement position and that is located at the measurement position via the rod R to the sampler S that is arranged in the hole. Is connected is provided with a striking mechanism 6 to obtain the N value by implanting sampler S to ground, the. [Selection diagram] Fig. 1

Description

  The present invention relates to a standard penetration test method and apparatus.

  As shown in Patent Literatures 1 to 3 and Non-Patent Literature 1, in a standard penetration test for obtaining ground strength, a sampler (steel pipe) connected to the lower end of a guide rod is set up in a hole in the ground, A 63.5 ± 0.5 kg hammer (drive hammer) is dropped from a height of 760 ± 10 mm onto an anvil (knocking block) fixed to a guide rod, and a sampler is driven. In the standard penetration test, the number of hits required to drive the sampler by 300 mm is obtained as an N value indicating the strength of the ground.

JP-A-08-201258 JP-A-2004-197349 JP 2005-023560 A

Japanese Industrial Standards Committee, [online], Home> Database Search> JIS Standard Detail Screen> JIS A 1219: 2013, [Search December 1, 1980], Internet (URL: https: //www.jisc. go.jp/pdfb2/PDFView/ShowPDF/rQIAAOs1WzEG-M_8zgCh)

  In such a standard penetration test, it is necessary to perform a manual operation at a high place by assembling a three-pronged scaffold that also serves as a scaffold, and the work load is large.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a standard penetration test method and apparatus that reduce the burden of a standard penetration test operation.

(1) The present invention relates to a standard penetration test apparatus used in a state where a number of rods corresponding to depths are connected to each other, and is provided so as to be able to retreat from a measurement position for obtaining an N value, and a drilling tool is provided at a lower part. An excavation mechanism that holds the rod so that the rod connected thereto penetrates and , at the measurement position, excavates a hole in the ground with the excavation tool by lowering the held rod while rotating the rod. wherein the reader rod being erected on the side of the rod drilling mechanism that holds, is provided movably along the leader for the rod, so that the rod the drilling mechanism that holds penetrates to hold the rod, the pulling said excavation tool by moving the rod upward by itself and held in a state of releasing the retention of the rod by the drilling mechanism on the ground, the ground in the excavation tool When being drilled, the rod chuck to release the holding of the rod, it said provided so as to be retracted from the measuring position in the measuring position, via the rod sampler disposed in said hole connection A hitting mechanism for driving the sampler into the ground to obtain an N value.

  According to the present invention, after excavating a hole in the ground, the N value can be obtained by retracting the excavation mechanism and arranging the striking mechanism at the measurement position. According to the present invention, the hole can be excavated in the ground by retreating the striking mechanism and arranging the excavating mechanism at the measurement position after obtaining the N value. This reduces the number of manual operations, so that the burden of the standard penetration test can be reduced.

  Further, according to the present invention, the rod is held by the rod chuck so that the rod penetrates, and the rod held by the rod chuck is moved upward to raise the excavation tool to the ground, so that the number of connected rods is reduced. Even if it increases, it can respond.

(2) The present invention also is a standard penetration test apparatus described in (1), characterized in that it comprises a drilling tool chuck that holds the drill tool has been raised to the ground.

  According to the present invention, the drilling tool can be removed from the rod by holding the drilling tool with the drilling tool chuck and then rotating the rod with the drilling mechanism. This reduces the number of manual operations, so that the burden of the standard penetration test can be reduced.

  (3) The present invention is also a standard penetration test method for obtaining an N value using the standard penetration test device according to the above (1) or (2), wherein the impact mechanism is retracted from the measurement position. A digging step of digging a hole with the digging mechanism arranged at the measuring position, and a measuring step of retracting the digging mechanism from the measuring position and obtaining an N value with the hitting mechanism arranged at the measuring position Wherein the excavation step and the measurement step are alternately repeated.

  According to the present invention, by alternately repeating the excavation step and the measurement step, it is possible to sequentially measure the N values at a plurality of depths while reducing the work load.

  According to the standard penetration test device described in the above (1) and (2) and the standard penetration test method described in the above (3) of the present invention, it is possible to reduce the burden of the work of the standard penetration test.

It is a front view of a standard penetration testing device concerning an embodiment of the present invention, (A) shows the state where the striking mechanism was turned down, and (B) shows the state where the striking mechanism was set up. FIG. 2 is a side view of the standard penetration test device shown in FIG. 1, wherein (A) shows a state in which the striking mechanism is depressed, and (B) shows a state in which the striking mechanism is set up. FIG. 2 is a front view of the standard penetration test apparatus shown in FIG. 1, wherein (A) shows a state in which a striking mechanism is arranged at a measuring position, and (B) shows a state in which the striking mechanism is retracted from the measuring position. FIG. 2 is a side view of the standard penetration test apparatus shown in FIG. 1, wherein (A) shows a state in which a digging mechanism and a rod support mechanism are arranged at a measurement position, and (B) retreats the digging mechanism and a rod support mechanism from the measurement position. This shows the state in which it is performed. FIG. 2 is a block diagram illustrating a configuration of a control panel provided in the standard penetration test device of FIG. 1. 2 is a flowchart illustrating a flow of a standard penetration test method by the standard penetration test device of FIG. 1. It is the schematic explaining the excavation procedure by the standard penetration test apparatus of FIG. 1, (A) shows the state which installed the drilling tool, (B) shows the state which connected the rod to the drilling tool, (C) (D) shows the state at the end of excavation, (E) shows the state where the excavator is pulled up to the ground, (F) shows the state where the rod is retracted, (G) () Shows a state in which the excavating mechanism and the rod support mechanism are retracted, and (H) shows a state in which the excavating tool is removed. FIG. 8 is a schematic view illustrating a procedure following the excavation procedure illustrated in FIG. 7 and illustrating a striking procedure performed by the standard penetration test apparatus illustrated in FIG. 1, wherein (A) illustrates a state where a sampler to which a rod is connected is installed in a hole. (B) shows a state in which a striking mechanism is connected to a rod connected to the sampler, (C) shows a state in which the hammer is raised to a predetermined height, and (D) shows a state in which the hammer is freely dropped. The state immediately after the hammer hits the anvil is shown, (E) shows the state after N value measurement, (F) shows the state where the hitting mechanism is retracted, and (G) shows the sampler and the rod removed. Indicates the status. FIG. 9 is a schematic view illustrating a procedure following the impact procedure illustrated in FIG. 8 and illustrating an excavation procedure using the standard penetration test apparatus illustrated in FIG. 1. FIG. (B) shows a state in which the retracted rod is connected to a rod connected to the excavator, (C) shows a state at the start of excavation, and (D) shows a state at the end of excavation. (E) shows a state in which the excavator is pulled up to the ground, (F) shows a state in which the rod is retracted, (G) shows a state in which the excavation mechanism and the rod support mechanism are retracted, and (H) ) Indicates a state in which the drilling tool has been removed.

  Hereinafter, a standard penetration test apparatus 1 according to an embodiment of the present invention will be described in detail with reference to the drawings. The arrow FR in the figure indicates the front of the standard penetration test device 1, and the arrow UR indicates the upper side. In the following description, the front-rear direction means the front-rear direction of the standard penetration test device 1, and the left-right direction means the left-right direction of the standard penetration test device 1 in a state facing forward.

  First, the configuration of the standard penetration test apparatus 1 according to the embodiment will be described with reference to FIGS. FIG. 1 is a front view of the standard penetration test apparatus 1. FIG. 1A shows a state in which the striking mechanism 6 is tilted. FIG. 1B shows a state in which the striking mechanism 6 is set up. FIG. 2 is a side view of the standard penetration test apparatus 1 shown in FIG. FIG. 2A shows a state in which the striking mechanism 6 is tilted. FIG. 2B shows a state in which the striking mechanism 6 is set up. FIG. 3 is a front view of the standard penetration test apparatus 1 shown in FIG. FIG. 3A shows a state where the striking mechanism 6 is arranged at the measurement position. FIG. 3B shows a state where the striking mechanism 6 is retracted from the measurement position. FIG. 4 is a side view of the standard penetration test apparatus 1 shown in FIG. 1, and FIG. 4A shows a state where the excavation mechanism 3 and the rod support mechanism 4 are arranged at the measurement position. FIG. 4B shows a state in which the excavating mechanism 3 and the rod supporting mechanism 4 have been retracted from the measurement position. FIG. 5 is a block diagram showing the configuration of the control panel 8 provided in the standard penetration test device 1 of FIG.

  The standard penetration test apparatus 1 shown in FIGS. 1 to 4 is used in a standard penetration test for determining the strength of the ground, and is used in a state where a number of rods R according to the depth are connected to each other. The standard penetration test is a test based on a standard penetration test method defined in Japanese Industrial Standards (JIS A 1219: 2013). In the standard penetration test, a sampler S connected to the lower end of the guide rod 60 is set up in a hole in the ground, and then a 63.5 ± 0.5 kg hammer of 760 ± 10 mm is attached to the anvil 62 fixed to the guide rod 60. Drop from the height and drive in sampler S. In this standard penetration test, the number of hits required to drive the sampler S by 300 mm is obtained as an N value indicating the strength of the ground. The rod R, the excavator D, the sampler S, the guide rod 60, and the anvil 62 are connected to each other by screws, and are connected or removed by rotating each other.

  Specifically, the standard penetration test apparatus 1 includes a base machine 2, an excavating mechanism 3, a rod supporting mechanism 4, an excavating tool supporting mechanism 5, a striking mechanism 6, a lifting mechanism 7, and a rotation sensor (sensor) 80. , A proximity sensor 81, a control panel 8 (see FIG. 5), an operation unit 9, and the like.

  The base machine 2 allows the standard penetration test device 1 to run on its own. Specifically, the base machine 2 includes a base body 20, a slide frame 21, a pair of left and right caterpillars 22, and front, rear, left and right outriggers 23, and the like.

  A slide frame 21 is attached to the upper part of the base body 20. The base body 20 has a pair of caterpillars 22 attached to the left and right of the base body 20, and outriggers 23 attached to the front, rear, left and right of the base body 20.

  The slide frame 21 is attached to the base body 20 so as to be slidable back and forth. The slide frame 21 slides back and forth with respect to the base body 20 by a hydraulic cylinder (not shown) or the like. The excavating mechanism 3 is attached to the center of the slide frame 21, the rod support mechanism 4 is attached to the left side, and the striking mechanism 6 and the lifting mechanism 7 are attached to the right side. Such a slide frame 21 slides back and forth with respect to the base body 20 so that the excavating mechanism 3, the rod supporting mechanism 4, the striking mechanism 6, and the lifting mechanism 7 can be retracted from the measurement position for obtaining the N value. .

  The excavating mechanism 3 is provided so as to be able to retreat from the measurement position, the rods R connected to each other can be inserted in the vertical direction, the swivel joint J connecting the hose H is connected to the upper part, and the excavating tool D is connected to the lower part. Is held or released, and at the measurement position, the held rod R is lowered while rotating to excavate a hole in the ground with the excavator D. The excavating mechanism 3 is attached to the center of a slide frame 21 that slides back and forth. The slide frame 21 is disposed at a measurement position together with the rod support mechanism 4 by moving the slide frame 21 forward, while the slide frame 21 is moved rearward. Move away from the measurement position together with the rod support mechanism 4.

  Specifically, the excavating mechanism 3 has a built-in chuck mechanism (not shown), a rotating mechanism (not shown), and the like. A chuck mechanism (not shown) holds or releases any part of the rod R at the middle. The rotation mechanism (not shown) includes a motor (not shown) and the like, and rotates the rod R held by the chuck mechanism.

  The rod support mechanism 4 is provided so as to be able to withdraw from the measurement position, holds or releases the rod R held or released by the excavation mechanism 3, and moves the held rod R upward to move the excavator D. Raise to the ground. The rod support mechanism 4 is mounted on the left side of a slide frame 21 that slides back and forth. The slide frame 21 moves forward and is arranged at the measurement position together with the excavation mechanism 3, while the slide frame 21 is moved rearward. And withdraws from the measurement position together with the excavation mechanism 3. Specifically, the rod support mechanism 4 includes a rod reader 40, a rod chuck 41, a rod chuck lifting / lowering mechanism (not shown), and the like.

  The rod leader 40 is provided on the left side of the slide frame 21 that slides back and forth so as to be extendable and retractable so as to be located beside the rod R that is held or released by the excavating mechanism 3. A rod chuck 41 is attached to the rod leader 40 so as to be movable along the rod leader 40. The rod reader 40 has a built-in rod chuck elevating mechanism (not shown).

  The rod chuck 41 is provided so as to be movable along the rod leader 40, and holds or releases the rod R rotatably so that the rod R held or released by the excavation mechanism 3 passes therethrough, The held rod R is moved upward, and the drilling tool D is pulled up to the ground. That is, the rod chuck 41 rotatably holds or releases any intermediate portion of the rod R.

  Specifically, the rod chuck 41 includes a chuck mechanism (not shown), a rotating mechanism (not shown), and the like. A chuck mechanism (not shown) holds or releases any part of the rod R at the middle. The rotation mechanism (not shown) includes a motor (not shown) and the like, and rotates the rod R held by the chuck mechanism (not shown).

  The rod chuck lifting / lowering mechanism (not shown) is composed of an endless chain (not shown) to which the rod chuck 41 is fixed, and the rod chuck 41 is attached to a rod reader as the endless chain (not shown) travels. Move up and down along 40.

  The digging tool support mechanism 5 functions as a digging tool chuck for holding or releasing the digging tool D lifted to the ground.

  The striking mechanism 6 is provided so as to be able to retreat from the measurement position. At the measurement position, the striking mechanism 6 is connected to a sampler S disposed in a hole via a rod R, and strikes the sampler S into the ground to obtain an N value. The striking mechanism 6 is attached to the right side of the slide frame 21 that slides back and forth, and can be arranged at the measurement position by moving the slide frame 21 backward, while moving the slide frame 21 forward. Withdraw from the measurement position with. Specifically, the striking mechanism 6 includes a guide rod 60, a hammer 61, an anvil 62, a guide rod leader 63, a hammer chuck 64, a hammer chuck elevating mechanism (not shown), a turning column 65, A mechanism 66 and the like are provided.

  The guide rod 60 is connected via an anvil 62 to a rod R to which a sampler S is connected at a lower part, and guides the free fall of the hammer 64. The guide rod 60 is vertically movably supported in front of the guide rod leader 63 so as to be parallel to the guide rod leader 63. The guide rod 60 has a hump 60a in the middle of the guide rod 60 (for example, at a position of 760 ± 10 mm from the lower end). When the hammer chuck 64 reaches the hump 60a, the hump 60a releases the holding of the hammer 61 by the hammer chuck 64 and allows the hammer 61 to freely fall.

  The hammer 61 is provided movably along the guide rod 60. The hammer 61 freely falls along the guide rod 60 and collides with the anvil 62, thereby hitting the anvil 62 and indirectly hitting the sampler S.

  The anvil 62 is interposed between the upper end of the rod R to which the sampler S is connected at the lower part and the lower end of the guide rod 60, and is hit by the hammer 61 that has fallen freely.

  The guide rod leader 63 is erected on the right side of the slide frame 21 that slides back and forth on the right side of the slide frame 21 that slides back and forth on the side of the rear side of the guide rod 60 so as to be parallel to the guide rod 60. You. A hammer chuck 64 is attached to the guide rod leader 63 so as to be movable along the guide rod leader 63. The guide rod reader 63 has a built-in hammer chuck elevating mechanism (not shown).

  The hammer chuck 64 is provided so as to be movable along the guide rod 60 and the guide rod leader 63, holds or releases the hammer 61, and moves the held hammer 61 upward before moving the hammer 61. Free fall. The hammer chuck 64 has a built-in proximity sensor 81 (see FIG. 5) for detecting holding and release of the hammer 61.

  The hammer chuck elevating mechanism (not shown) includes an endless chain (not shown) to which the hammer chuck 64 is fixed, a sprocket (not shown) for running the endless chain (not shown), and the like. As the chain (not shown) travels, the hammer chuck 64 is moved up and down along the guide rod leader 63.

  The revolving support 65 is provided on the right side of the slide frame 21 that slides back and forth so as to be rotatable about the axis. The turning column 65 supports a guide rod leader 63 at the upper end of the turning column 65 via an up / down mechanism 66 so as to be rotatable. By rotating the guide rod leader 63 by rotating the pivot 65, the striking mechanism 6 can be retracted from the measurement position, and the lifting mechanism 7 is arranged at the measurement position.

  The raising / lowering mechanism 66 is interposed between the guide rod leader 63 and the turning column 65, and supports the guide rod leader 63 so as to be able to raise and lower.

  The lifting mechanism 7 is provided behind the guide rod reader 63. The lifting mechanism 7 is used when lifting the sampler S from a hole. Specifically, the lifting mechanism 7 includes a winch 70, a wire 71, a pulley 72, a hook 73, and the like.

  The winch 70 is provided on the back surface of the guide rod reader 63. The winch 70 raises and lowers the hook 73 attached to the tip of the wire 71 by winding and unwinding the wire 71.

  The wire 71 extends from the winch 70 along the guide rod leader 63 toward the upper pulley 72, and is folded back at the pulley 72 and extends downward. The wire 71 is wound or fed out of the winch 70 to raise and lower a hook 73 provided at the tip of the wire 71.

  The pulley 72 is provided above the guide rod leader 63. The pulley 72 hooks a wire 71 extending from the winch 70 along the guide rod leader 63, and turns the wire 71 downward.

  The hook 73 is attached to the tip of the wire 71. The hook 73 is hung on the wire 71, and the wire 71 is wound up and paid out, so that the hook 73 is raised and lowered.

  The rotation sensor 80 (see FIG. 5) detects a distance at which the sampler S is driven into the ground as a hitting distance. The rotation sensor 80 (see FIG. 5) measures the rotation amount of a sprocket (not shown) of the hammer chuck lifting / lowering mechanism (not shown) in the striking mechanism 6 to determine the movement distance of the hammer chuck 64 from the initial position. It is detected as the impact distance. Then, the rotation sensor 80 (see FIG. 5) transmits the detected hitting distance to the control panel 8 (see FIG. 5) as a signal.

  The proximity sensor 81 (see FIG. 5) is built in the hammer chuck 64. The proximity sensor 81 (see FIG. 5) detects that the hammer chuck 64 has approached the hammer 61 when the hammer chuck 64 holds the hammer 61, and detects when the hammer chuck 64 releases the holding of the hammer 61. Detect that the hammer chuck 64 has stopped approaching the hammer 61. Then, the proximity sensor 81 (see FIG. 5) transmits the detected result as a signal to the control panel 8 (see FIG. 5).

  The control panel 8 shown in FIG. 5 totally controls the standard penetration test apparatus 1 based on signals transmitted from the rotation sensor 80, the proximity sensor 81, and the operation unit 9. Specifically, the control panel 8 has a data logger 82 and a CPU (Central Processing Unit) 83.

  The data logger 82 is configured by a recording medium such as a RAM (Random Access Memory). The data logger 82 stores a processing program for the CPU 83 to execute various processes and various data and various flags used when executing the various processes.

  The CPU 83 functions as a counter 84, a calculating unit 85, and the like by executing the processing program stored in the data logger 82.

  The counter 84 counts the number of hits of the sampler S on the ground as the number of hits. The counter 84 counts the number of free falls of the hammer 61 (see FIG. 2 and the like) as the number of hits based on a signal transmitted from the proximity sensor 81. Then, the counter 84 transmits the counted number of hits as a signal to the calculating unit 85.

  The calculation unit 85 calculates the number of hits transmitted as a signal from the counter 84 as an N value when the hitting distance transmitted as a signal from the rotation sensor 80 reaches a predetermined value (300 mm). That is, the calculation unit 85 calculates the number of hits counted by the counter 84 as an N value when the hitting distance detected by the rotation sensor 80 reaches a predetermined value.

  Various operations are performed on the operation unit 9 to operate the standard penetration test device 1. The operation unit 9 transmits various signals to the control panel 8 when various operations are performed.

  Next, the flow of the standard penetration test method using the standard penetration test apparatus 1 will be described with reference to FIGS. FIG. 6 is a flowchart illustrating the flow of the standard penetration test method by the standard penetration test device 1 of FIG.

  FIG. 7 is a schematic diagram illustrating an excavation procedure by the standard penetration test device 1 of FIG. FIG. 7A shows a state where the excavating tool D is installed. FIG. 7B shows a state in which the rod R is connected to the drilling tool D. FIG. 7C shows a state at the start of excavation. FIG. 7 (D) shows a state at the end of excavation. FIG. 7E shows a state where the excavating tool D is pulled up to the ground. FIG. 7F shows a state where the rod R is retracted. FIG. 7G shows a state in which the excavating mechanism 3 and the rod supporting mechanism 4 are retracted. FIG. 7 (H) shows a state in which the drilling tool D has been removed.

  FIG. 8 is a schematic diagram that is a procedure that follows the excavation procedure shown in FIG. 7 and that explains the impact procedure by the standard penetration test apparatus 1 of FIG. 1. FIG. 8A shows a state where the sampler S to which the rod R is connected is installed in the hole. FIG. 8B shows a state in which the striking mechanism 6 is connected to the rod R connected to the sampler S. FIG. 8C shows a state where the hammer 61 is raised to a predetermined height. FIG. 8D shows a state immediately after the hammer 61 falls freely and the hammer 61 hits the anvil 62. FIG. 8E shows a state after the N value measurement. FIG. 8F shows a state where the impact mechanism 6 is retracted. FIG. 8G shows a state in which the sampler S and the rod R have been removed.

  FIG. 9 is a schematic view that is a procedure that follows the impact procedure shown in FIG. 8 and that describes the excavation procedure using the standard penetration test apparatus 1 shown in FIG. FIG. 9 (A) shows a state where the excavating tool D to which the rod R is connected is installed. FIG. 9B shows a state in which the retracted rod R is connected to the rod R connected to the excavation tool D. FIG. 9C shows a state at the start of excavation. FIG. 9D shows a state at the time of completion of excavation. FIG. 9E shows a state in which the excavator D is pulled up to the ground. FIG. 9F shows a state where the rod R is retracted. FIG. 9 (G) shows a state in which the excavating mechanism 3 and the rod supporting mechanism 4 are retracted. FIG. 9 (H) shows a state where the drilling tool D has been removed.

  As shown in FIG. 6, the standard penetration test method using the standard penetration test device 1 (see FIGS. 1 to 4) includes an excavation step S100 and a measurement step S200. The measurement step S200 is repeated alternately.

  In the excavation step S100, the impact mechanism 6 is retracted from the measurement position, and a hole is excavated by the excavation mechanism 3 arranged at the measurement position. In the measuring step S200, the excavating mechanism 3 is retracted from the measuring position, and the N value is obtained by the striking mechanism 6 arranged at the measuring position S200.

  First, in the first excavation step S100, work is performed according to the excavation procedure shown in FIGS. 7 (A) to 7 (G).

  As shown in FIG. 7 (A), after the impact mechanism 6 is retracted from the measurement position and the excavation mechanism 3 is arranged at the measurement position, the excavation tool D is erected on the ground, and then the excavation tool D is excavated. It is held by the tool support mechanism 5.

  As shown in FIG. 7B, the three rods R connected to each other are inserted into the excavating mechanism 3 from above, and then the excavating tool D is connected to the lower part of the rod R. And the swivel joint J to which the hose H is connected.

  As shown in FIG. 7C, excavation can be started by holding the rod R by the excavation mechanism 3 and releasing the holding of the excavation tool D by the excavation tool support mechanism 5.

  As shown in FIG. 7D, the excavating mechanism 3 lowers the rod R while rotating it, and excavates a hole in the ground with the excavator D. At the time of excavation, muddy water is supplied from an excavator D via a hose H and a rod R as necessary.

  As shown in FIG. 7 (E), after the rod R is held by the rod chuck 41 and the holding of the rod R by the excavation mechanism 3 is released, the rod R is moved upward by the rod support mechanism 4 to thereby excavate the excavator D. Is lifted to the ground, and the digging tool D is held by the digging tool support mechanism 5.

  As shown in FIG. 7F, the rod R is detached from the excavation tool D by rotating the rod R with the rod chuck 41, and then the rod R is retracted upward by the rod support mechanism 4.

  As shown in FIG. 7 (G), the excavation mechanism 3 and the rod support mechanism 4 are retracted from the measurement position.

  As shown in FIG. 7H, the holding of the drilling tool D by the drilling tool support mechanism 5 is released, and the drilling tool D is removed.

  Further, at the measurement position S200, the operation is performed according to the hitting procedure shown in FIGS. 8A to 8G.

  As shown in FIG. 8A, after the excavating mechanism 3 is retracted from the measurement position, the sampler S to which the rods R are connected is set up in the hole so that one rod R is placed on the ground. Set up.

  As shown in FIG. 8B, after the striking mechanism 6 is arranged at the measurement position, the striking mechanism 6 is connected to the rod R connected to the sampler S.

  As shown in FIG. 8C, by raising the hammer 61 to a predetermined height at which the hammer chuck 64 reaches the hump 60a, the holding of the hammer 61 by the hammer chuck 64 is released, and the hammer 61 is allowed to fall freely. Start.

  As shown in FIG. 8D, when the hammer 61 that has fallen freely hits the anvil 62, the impact of the hit is transmitted to the sampler S via the rod R, and the sampler S is driven into the ground.

  As shown in FIG. 8 (E), the N value is obtained by the control panel 8 by repeatedly hitting with the hammer 61 until the sampler S reaches a predetermined depth.

  As shown in FIG. 8F, after the connection between the rod R connected to the sampler S and the striking mechanism 6 is released, the striking mechanism 6 is retracted from the measurement position.

  As shown in FIG. 8 (G), the sampler S and the rod R are removed using the lifting mechanism 7.

In the excavation step S100 to be repeatedly performed, the work is performed according to the excavation procedure shown in FIGS. 9A to 9G.

  As shown in FIG. 9A, the excavator D connected to the rod R is erected in the hole, and then the rod R is held by the excavator support mechanism 5, and the excavator 3 is arranged at the measurement position. Let it.

  As shown in FIG. 9B, after the rod R retracted upward is moved downward by the rod support mechanism 4, the rod R is held by the excavation mechanism 3 and the rod R is held by the rod chuck 41. By releasing the holding and rotating the rod R by the excavating mechanism 3, the rod R that has been retracted upward is connected to the rod R connected to the excavating tool D.

  As shown in FIG. 9C, excavation can be started by releasing the holding of the rod R by the excavation tool support mechanism 5.

  As shown in FIG. 9D, the excavating mechanism 3 lowers the rod R while rotating it, and excavates a hole in the ground with the excavator D. At the time of excavation, muddy water is supplied from an excavator D via a hose H and a rod R as necessary.

  As shown in FIG. 9 (E), after the rod R is held by the rod chuck 41 and the holding of the rod R by the excavation mechanism 3 is released, the rod R is moved upward by the rod support mechanism 4 to excavate the drilling tool D. Is lifted to the ground, and the digging tool D is held by the digging tool support mechanism 5.

  As shown in FIG. 9 (F), the rod R is detached from the digging tool D by rotating the rod R with the rod chuck 41, and then the rod R is retracted upward by the rod support mechanism 4.

  As shown in FIG. 9 (G), the excavation mechanism 3 and the rod support mechanism 4 are retracted from the measurement position.

  As shown in FIG. 9H, the holding of the digging tool D by the digging tool support mechanism 5 is released, and the digging tool D is removed.

  As described above, the standard penetration test apparatus 1 is an apparatus that uses a number of rods R corresponding to the depth in a state of being connected to each other. The standard penetration test apparatus 1 is provided so as to be able to retreat from a measurement position for obtaining an N value, and holds or releases a rod R connected to a lower part of a drilling tool D, and holds the rod R at the measurement position. An excavating mechanism 3 for excavating a hole in the ground with an excavating tool D by lowering the rod R while rotating the rod R, a rod reader 40 standing upright beside the rod R held or released by the excavating mechanism 3, The excavating mechanism 3 is provided so as to be movable along the rod leader 40, holds or releases the rod R to be held or released by the excavation mechanism 3, and moves the held rod R upward. A rod chuck 41 for lifting the drilling tool D to the ground is provided so as to be retractable from the measurement position. At the measurement position, the rod chuck 41 is connected to a sampler S disposed in a hole via a rod R. Includes a striking mechanism 6 to obtain the N value dedicated to ground, the sampler S Te.

  Therefore, according to the standard penetration test apparatus 1, after excavating a hole in the ground, the N value can be obtained by retracting the excavation mechanism 3 and arranging the impact mechanism 6 at the measurement position. Then, according to the standard penetration test apparatus 1, after obtaining the N value, the impact mechanism 6 is retracted and the excavating mechanism 3 is arranged at the measurement position, so that a hole can be excavated in the ground. This reduces the number of manual operations, so that the burden of the standard penetration test can be reduced.

  Further, according to the standard penetration test apparatus 1, the rod R is held by the rod chuck 41 so that the rod R penetrates, and the rod R held by the rod chuck 41 is moved upward to raise the excavation tool D to the ground. Therefore, even if the number of connected rods R increases, it is possible to cope with the case.

  Moreover, the standard penetration test apparatus 1 is provided with a digging support mechanism 5 for holding or releasing a digging tool pulled up to the ground.

  Therefore, according to the standard penetration test apparatus 1, the drilling tool D can be removed from the rod by holding the drilling tool D by the drilling tool support mechanism 5 and then rotating the rod R by the drilling mechanism 3. This reduces the number of manual operations, so that the burden of the standard penetration test can be reduced.

  In addition, the standard invitation test apparatus 1 includes a rotation sensor 80 that detects a distance at which the sampler S is driven into the ground as a hitting distance, a counter 84 that counts the number of times the sampler S is driven into the ground as the number of hits, and a rotation sensor 80. A calculating unit 85 for calculating the number of hits counted by the counter 84 as an N value when the detected hitting distance reaches a predetermined value, wherein the hitting mechanism 6 has a sampler S connected to a lower part. A guide rod 60 connected to the rod R, a hammer 61 that freely falls along the guide rod 60, a rod R connected to the lower part of the sampler S, and the guide rod 60 An anvil 62 hit by the hammer 61 that has fallen freely, and a guide rod leader 63 erected by the guide rod 60; A hammer chuck 64 that is provided so as to be movable along the id rod leader 63, holds or releases the hammer 61, moves the held hammer 61 upward, and free-falls the hammer 61. Then, the rotation sensor 80 detects the moving distance of the hammer chuck 64 from the initial position as a striking distance, and the counter 84 counts the number of free falls of the hammer 61 as the number of striking.

  Therefore, according to the standard penetration test apparatus 1, the hammer chuck 64 for moving the hammer 61 upward and then free-falling the hammer 61, and the rotation sensor for detecting the moving distance of the hammer chuck 64 from the initial position as the striking distance. 80, a counter 84 that counts the number of free falls of the hammer 61 as the number of hits, and the number of hits counted by the counter 84 when the hit distance detected by the rotation sensor 80 reaches a predetermined value. Since the calculation unit 85 for calculating the value is provided, the N value can be obtained without manual operation. Thereby, the burden of the work of the standard penetration test can be reduced.

  Further, the standard penetration test method is a method of obtaining the N value using the standard penetration test apparatus 1, in which the impact mechanism 6 is retracted from the measurement position, and a hole is excavated by the excavation mechanism 3 arranged at the measurement position. Excavation step S100, and a measurement step S200 for retreating the excavation mechanism 3 from the measurement position and obtaining an N value with the striking mechanism 6 arranged at the measurement position. The excavation step S100 and the measurement step S200 are alternately performed. repeat.

  Therefore, according to the standard penetration test method by the standard penetration test apparatus 1, by repeating the excavation step S100 and the measurement step S200, it is possible to reduce the work load and measure the N values at a plurality of depths according to the standard. it can.

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit and technical idea thereof. That is, the position, size, length, quantity, shape, material, and the like of each component can be appropriately changed.

  For example, in the above embodiment, the rotation sensor 80 included in the standard penetration test apparatus 1 measures the rotation amount of a sprocket (not shown) of the hammer chuck lifting / lowering mechanism (not shown) in the striking mechanism 6, so that the hammer can be measured. Although the case where the movement distance of the chuck 64 from the initial position is detected as the impact distance has been described as an example, the present invention is not limited to the case where the standard penetration test device 1 is provided with the rotation sensor 80, and the standard penetration test device 1 May be equipped with any sensor that detects the distance at which the sampler S is driven into the ground as a hitting distance.

  Alternatively, in the above-described embodiment, an example will be described in which the counter 84 included in the standard penetration test device 1 counts the number of free falls of the hammer 61 as the number of hits based on a signal transmitted from the proximity sensor 81. However, the present invention is not limited to the standard penetrating test apparatus 1 having the counter 84, and the standard penetrating test apparatus 1 is provided with any counter that counts the number of free falls of the hammer 61 as the number of hits. It may be something.

DESCRIPTION OF SYMBOLS 1 Standard penetration test apparatus 2 Base machine 20 Base main body 21 Slide frame 22 Caterpillar 23 Outrigger 3 Excavation mechanism 4 Rod support mechanism 40 Rod leader 41 Rod chuck 5 Excavation tool support mechanism (Excavation tool chuck)
Reference Signs List 6 hitting mechanism 60 guide rod 60a hump 61 hammer 62 anvil 63 guide rod reader 64 hammer chuck 65 turning prop 66 undulating mechanism 7 lifting mechanism 70 winch 71 wire 72 pulley 73 hook 8 control panel 80 rotation sensor (sensor)
81 Proximity sensor 82 Data logger 83 CPU
84 Counter 85 Calculation unit 9 Operation unit R Rod D Drilling tool S Sampler J Swivel joint H Hose FR Front UR Above S100 Drilling process S200 Measurement process

Claims (3)

A standard penetration test device used in a state where the number of rods according to the depth are connected to each other,
Provided so as to be retracted from the measuring position to determine the N value, the rod drilling tool is connected to the lower part holds the rod to pass through, rotating in said measuring position, said rod being held An excavating mechanism for lowering while excavating and excavating a hole in the ground with the excavating tool,
A reader rod being erected on the side of the rod the drilling mechanism that holds,
Is provided movably along the leader for the rod, said rod drilling mechanism that holds holds the rod so as to penetrate itself in a state releasing the retention of the rod by the drilling mechanism A rod chuck for releasing the holding of the rod when the held rod is moved upward to lift the excavation tool to the ground, and when excavating a hole in the ground with the excavation tool ,
A striking mechanism that is provided so as to be retractable from the measurement position, is connected to the sampler disposed in the hole via the rod at the measurement position, and drives the sampler into the ground to obtain an N value. A standard penetration testing device characterized by having: SPT device according to claim 1, characterized in that it comprises a drilling tool chuck that holds the drill tool has been raised to the ground. A standard penetration test method for obtaining an N value using the standard penetration test device according to claim 1 or 2,
An excavation step of retracting the impact mechanism from the measurement position and excavating a hole with the excavation mechanism arranged at the measurement position;
A measurement step of retracting the excavation mechanism from the measurement position and obtaining an N value with the striking mechanism arranged at the measurement position,
A standard penetration test method characterized by alternately repeating the excavation step and the measurement step.

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