Ground testing apparatus and ground testing method

Abstract

The object of the present invention is to solve the problems of the prior art, namely, to provide a ground testing apparatus that allows for easier movement of the drilling means than the prior art, and a ground testing method using the same. [Solution] The ground testing apparatus of the present invention comprises a base installed on the ground, a drilling column, a slider, a rotary drive body, a drilling rod, and a testing means. Of these, the drilling column is attached to the base so as to be rotatable around a substantially horizontal axis. By rotating the drilling column, to which the rotary drive body is attached, around a substantially horizontal axis, the rotary drive body is moved to a position away from the test hole, and the test using the testing means can be performed using the test hole.

Description

Technical Field

[0004] , , , , ,

[0003]

[0001] The present invention relates to boring surveys of the ground. More specifically, it relates to a ground testing apparatus that combines boring means for drilling test holes and testing means for performing in-situ tests on the ground, and can move the boring means to a position outside the test hole when performing tests by the testing means, and a method for testing the ground using this apparatus.

Background Art

[0002] Transmission towers are one of the extremely important facilities for stably supplying power to consumers. Naturally, they have a robust structure and, in principle, settlement (especially uneven settlement) is not allowed. Therefore, important and large-weight structures such as transmission towers are constructed on a supporting layer where a considerable bearing capacity can be expected, such as bedrock or a compacted sand layer. For example, in the case of a transmission tower, it is often structured such that a foundation is constructed on the supporting layer and the leg members are fixed to the foundation, that is, the form of obtaining support from the supporting layer through the foundation is common. [[ID=1至14]]

[0003] When the supporting layer is at a relatively shallow position, it is possible to excavate to a predetermined depth to expose the supporting layer and directly construct a foundation (so-called "direct foundation") on this supporting layer. On the other hand, when the supporting layer is at a relatively deep position, a considerable amount of excavation is required to expose the supporting layer, and furthermore, the construction of a large-scale foundation is necessary, and a direct foundation is not practical. Therefore, in such cases, a "pile foundation" is adopted instead of a direct foundation.

[0004] To compare and contrast direct foundations and pile foundations, or to plan and design direct foundations or pile foundations, it is necessary to understand the depth and geological (rock) characteristics of the bearing layer. Typically, a standard penetration test, as defined by the Japanese Industrial Standard (JIS A 1219), is performed. The standard penetration test is an in-situ test in which the N-value is measured every 1 meter while drilling a test hole, and a sample (core) is taken. The test uses a striking device (hammer, guide rod, anvil, dropping device, etc.), a drilling rod, a sampler, drilling equipment (usually a rotary boring machine), and a three-pronged rig.

[0005] As such, the standard penetration test requires various equipment and devices, and some of them, such as the rotary boring machine (approximately 300 kg), are relatively heavy. Therefore, transportation to the site is often an obstacle to conducting the test. In particular, in the case of power transmission towers, they are sometimes installed in mountainous areas with no traffic of people or vehicles, meaning that roads and other access routes to the site are not in place, making the transportation of equipment for the standard penetration test a major obstacle. If the total weight of the equipment is not too great, it can be transported by engine-driven crawlers, but in the case of the standard penetration test, the total weight of the equipment exceeds 1 ton, so such transportation is not feasible.

[0006] Traditionally, transporting equipment for standard penetration tests to test sites inaccessible to vehicles involved constructing temporary transport facilities such as monorails or cableways, and using these facilities to transport the equipment in small quantities. However, constructing monorails or cableways required considerable effort and cost, and considering the effort and cost of removal, they were often left in place until the test equipment was removed. As a result, the depreciation costs associated with the monorails and cableways also increased the overall cost of the operation.

[0007] Patent Document 1 proposes a test apparatus and test method with a reduced total weight (290 kg). Specifically, it is a technique for drilling a test hole using only hammer strikes, that is, a technique for performing a penetration test without using a boring machine. This makes it possible to measure the N value (NP value) and take core samples, so to speak, to perform a test that conforms to the standard penetration test. Moreover, as a result of reducing the weight of the test equipment, it can be transported by an engine-driven crawler, thus avoiding the construction of a monorail or similar structure. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Patent No. 6619235 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] The technology disclosed in Patent Document 1 allows for the implementation of tests similar to standard penetration tests without the need to construct monorails or the like, thus at low cost. However, because it does not use a rotary boring machine, its drilling capacity is somewhat inferior to conventional technologies. With the technology of Patent Document 1, for example, it is difficult to drill into ground where layers with an N-value of 50 or higher are continuous for 2 meters or more, and the drilling depth is generally limited to about 20 meters.

[0010] Incidentally, depending on the type of rock in the ground being tested (for example, granite), core stones (boulders or pebbles) may be present, and if these core stones are found at the drilling location, continuous drilling through a hard layer (for example, a layer with an N value of 50 or higher) becomes unavoidable. Furthermore, when using pile foundations, it is not uncommon for the supporting layer to be at a depth of 20m or more. In other words, in such cases, it is not possible to conduct investigations using the technology described in Patent Document 1. However, if conventional technology is adopted, the construction of monorails, etc., becomes unavoidable, and the cost of testing and the working time must be accepted.

[0011] Therefore, the inventors of the present invention came up with the idea of ​​drilling a test hole using a relatively lightweight core drill. This core drill is equipped with an electric motor, which causes the rotating shaft (drill shaft) to rotate at high speed. Normally, core drills are fitted with a cylindrical core bit equipped with a diamond bit and are used to take cores from concrete structures, stone materials, etc. That is, the core bit rotates together with the rotating shaft of the core drill to drill a hole in the concrete, and as the drilling progresses, a concrete core is taken into the core bit.

[0012] As mentioned above, core drills are relatively lightweight and rotate at high speeds. For example, the "Dymo Drill (registered trademark) TS-165" manufactured by Shibuya Co., Ltd. has a rotation speed of 1000 / 700 rpm and weighs 15.5 kg, while the "Dymo Drill TS-405" has a rotation speed of 700 / 300 rpm and weighs 30.9 kg.

[0013] When a test hole is formed with a core drill, an in-situ test of the ground is performed using this test hole. However, since the core drill is set above the test hole, it cannot be performed without moving it. For example, when performing a standard penetration test, after drilling a predetermined length (e.g., 50 cm), the core drill is moved, the test equipment is set up and the standard penetration test is performed, and after the test is finished, the core drill is set up above the test hole again. This series of operations is repeated. In this way, in order to alternate between drilling and testing, a so-called "setup change" is necessary, and it is desirable to reduce the effort and time involved in this setup change as much as possible.

[0014] To easily move the core drill, one could consider rotating it around a support column (i.e., a vertical axis). By erecting a support column on the ground, attaching a jig to the column axis so that it can rotate, and then mounting the core drill on this jig, the jig and core drill can be rotated to move horizontally to a position away from the test hole. However, in order to move the core drill to a position that does not interfere with the testing equipment, a certain amount of rotation (radius of rotation) is required, meaning that the arm length of the jig to which the core drill is mounted (the length extending from the support column) must be of a certain length. However, if the arm of the jig is made long in this way, a large bending moment will be generated in the support column as the core drill drills, so the support column will need to have considerable rigidity, which is undesirable in terms of transportation time and cost. In addition, because the core drill rotates at high speed, it vibrates violently during drilling, which may result in wobbling of the drilling rod, preventing the formation of an appropriate test hole, or even creating a situation where the worker is in danger.

[0015] The object of the present invention is to solve the problems of the prior art, namely, to provide a ground testing apparatus that allows for easier movement of the drilling means than the prior art, and a ground testing method using the same. [Means for solving the problem]

[0016] The present invention focuses on the fact that a drilling means is moved to a position away from the test hole by rotating a drilling support column to which a rotary drive body (e.g., a core drill) is attached around a substantially horizontal (including horizontal) axis, and is based on an unprecedented idea.

[0017] The ground testing apparatus of the present invention comprises a base installed on the ground, a drilling column, a slider, a rotary drive unit, a drilling rod, and a testing means. The drilling column is mounted on the base so as to be rotatable around a substantially horizontal (including horizontal) axis, and the slider is mounted on the drilling column so as to move in the axial direction of the drilling column. The rotary drive unit is attached to the slider, and the drilling rod is connected to the rotary drive unit. With the drilling column positioned substantially vertically (including vertical), the rotary drive unit rotates the drilling rod to form a test hole in the ground. Then, by rotating the drilling column to which the rotary drive unit is attached around a substantially horizontal (including horizontal) axis, the rotary drive unit is moved to a position away from the test hole, and the test using the testing means can be performed using the test hole.

[0018] The ground testing apparatus of the present invention may also be further equipped with a stopper. This stopper can rotate around a substantially horizontal (including horizontal) axis to fix the inclined drilling support column.

[0019] The ground testing apparatus of the present invention may also be configured to perform a standard penetration test using a test hole. In this case, the testing means comprises a test support column positioned substantially vertically (including vertically) and fixed to a base, a hammer inserted through a guide rod and falling along the guide rod, a knocking head connected to the lower end of the guide rod, and a test rod connected to the knocking head.

[0020] The ground testing apparatus of the present invention may further include a support means comprising a first arm and a second arm. The first arm is pin-connected to the test column, and the second arm is pin-connected to the first arm. In this case, the first arm, which rotates around a substantially horizontal (including horizontal) axis, is positioned substantially horizontally (including horizontal), and the second arm, which rotates around a substantially horizontal (including horizontal) axis, is positioned substantially vertically (including vertical). The lower end of the second arm is connected to the upper end of the drilling column, which is positioned substantially vertically (including vertical). With the drilling column supported by the support means, the drilling rod can be rotated.

[0021] The ground testing method of the present invention is a method for testing the ground using the ground testing apparatus of the present invention, and comprises a support column installation step, an equipment installation step, a drilling step, and a drilling means movement step. In the support column installation step, a base is installed on the ground and a drilling support column is attached to the base so as to be rotatable around a substantially horizontal (including horizontal) axis. In the equipment installation step, a slider to which a rotary drive body is attached is attached to the drilling support column and a drilling rod is connected to the rotary drive body. In the drilling step, a test hole is formed in the ground by rotating the drilling rod with the rotary drive body. In the drilling means movement step, the rotary drive body is moved to a position away from the test hole by rotating the drilling support column to which the rotary drive body is attached around a substantially horizontal (including horizontal) axis. After the drilling means movement step, a test can be performed using the test means through the test hole.

[0022] The ground testing method of the present invention can also be a method of performing a standard penetration test using a test hole. In this case, the ground testing apparatus consists of a test support column that is positioned approximately vertically (including vertically) and fixed to a base, a hammer that is inserted through a guide rod and falls along the guide rod, a knocking head connected to the lower end of the guide rod, and a test rod connected to the knocking head.

[0023] The ground test method of the present invention can also be a method of rotating a rod with a core tube connected to its lower end. In this case, in the drilling process, drilling is carried out while collecting a core in the core tube.

Advantages of the Invention

[0024] The ground test device and the ground test method of the present invention have the following effects. (1) Since it is lighter than the total weight (over about 1 t) of the device used in the conventional standard penetration test, for example, even in the case of transporting equipment to a test site in mountainous areas, it can be transported by an engine-driven crawler or the like without constructing temporary facilities for transportation such as a monorail or a cableway. As a result, the labor and cost associated with temporary facilities and equipment transportation can be reduced, and the period required for the entire operation can also be shortened. (2) The drilling support column with the rotary drive body can be easily moved by rotating it as if it were being toppled, that is, the labor and time involved in setup change can be significantly reduced. (3) By using the support means for the support column, the drilling support column is firmly supported, and thereby the drilling rod can drill the ground in a stable state.

Brief Description of the Drawings

[0025] [Figure 1] Side view showing the ground test device of the present invention. [Figure 2] Side view showing the drilling means constituting the ground test device. [Figure 3] Side view showing the state in which the drilling support column is rotated by the rotation mechanism constituting the drilling means. [Figure 4] Partial side view schematically showing the rotation mechanism. [Figure 5] Side view schematically showing the core drill attached to the slider. [Figure 6] (a) is a cross-sectional view showing the assembled speed reducer, and (b) is an exploded view showing each part constituting the speed reducer. [Figure 7] Plan view schematically showing the speed reducer main body using a planetary gear mechanism. [Figure 8] A schematic perspective view showing a speed reducer equipped with a stopper mechanism consisting of a left arm, a right arm, and a connecting bar. [Figure 9] A schematic perspective view illustrating a water swivel. [Figure 10] (a) is a schematic side view showing each part that constitutes the support column mechanism, and (b) is a side view showing the situation in which the support column mechanism connected to the test column supports the drilling column. [Figure 11] A flowchart showing the main steps of the ground testing method of the present invention. [Modes for carrying out the invention]

[0026] An example of an embodiment of the ground testing apparatus and ground testing method of the present invention will be described with reference to the figures.

[0027] 1. Ground testing equipment First, the ground testing apparatus of the present invention will be explained with reference to the diagram. The ground testing method of the present invention is a method of performing in-situ testing of the ground using the ground testing apparatus of the present invention. Therefore, the ground testing apparatus of the present invention will be explained first, and then the ground testing method of the present invention will be explained.

[0028] Figure 1 is a side view (cross-sectional view for underground) of the ground testing device 100 of the present invention. As shown in this figure, the ground testing device 100 of the present invention is composed of a "drilling means 200" that drills into the ground to form a hole (hereinafter referred to as "test hole TH"), a "test means 300" that performs a ground test using the test hole TH, and a base 400. On this base 400, the drilling means 200 is positioned on one side of the test hole TH, and the test means 300 is positioned on the other side. For convenience, the direction in which the drilling means 200 and the test means 300 are aligned as shown in Figure 1 will be referred to as the "transverse direction," and the side of the transverse direction on which the drilling means 200 is located will be referred to as the "front," and the side on which the test means 300 is located will be referred to as the "rear."

[0029] The base 400, which constitutes the ground testing apparatus 100, is formed by assembling steel materials and is usually installed on the ground. This base 400 is the foundation that supports the drilling means 200 and the testing means 300, and is therefore firmly fixed to the ground using anchor materials that can be driven into the ground (hereinafter referred to as "base anchors 401"). For example, in Figure 1, multiple base anchors 401 are driven in until sufficient embedment is achieved, and the base 400 is connected and fixed to the multiple base anchors 401 using clamps, etc. When drilling at a test site where it is difficult to transport each component, it is advisable to make the base 400 a structure consisting of multiple parts, and to assemble each part on-site after it has been transported individually. The drilling means 200 and the testing means 300 will be described in order below.

[0030] 1-1. Drilling means Figure 2 is a side view (cross-sectional view for underground) of the drilling means 200 that constitutes the ground testing device 100 of the present invention. As shown in Figures 1 and 2, the drilling means 200 is composed of a drilling column 201, a slider 202, a rotary drive body 203, and a drilling rod 205, and can further be composed of a reduction body 204, a core tube 206, a column support means 207, and a water supply mechanism 208, which will be described later. The main elements that constitute the drilling means 200 will be described in detail below.

[0031] (Drilling support) The drilling support column 201, which constitutes the drilling means 200, is a hollow or solid columnar member, its legs attached to the base 400, and when drilling is performed by the drilling means 200, its column axis is approximately vertical (including the vertical). The drilling support column 201 is also equipped with a rotation mechanism 209, which is attached to the base 400 so as to rotate around an approximately horizontal (including the horizontal) axis, that is, within an approximately vertical plane (including the vertical plane). The rotation mechanism 209 will be described below.

[0032] Figure 3 is a side view (cross-sectional view for underground) showing the drilling column 201 rotated by the rotating mechanism 209 that constitutes the drilling means 200, and Figure 4 is a schematic partial side view showing an example of the rotating mechanism 209. As shown in this figure, the rotating mechanism 209 rotates the drilling column 201 around a substantially horizontal axis, and in particular can rotate the drilling column 201 with the slider 202 and rotary drive unit 203 attached. As shown in Figure 3, when the drilling column 201 is rotated around a substantially horizontal axis, or more specifically, when the drilling column 201 is rotated so that it tilts forward, the drilling means 200 moves to a position away from the test hole TH, so that the test means 300 can perform an in-situ test of the ground using the test hole TH. In other words, thanks to the effect of having a rotating mechanism 209, it is possible to easily transition to an in-situ test simply by rotating the drilling column 201.

[0033] When rotating the drilling column 201, various conventional techniques can be used, such as using a winch or a lever block (registered trademark). Alternatively, a rotation mechanism 209 as shown in Figure 4 can be adopted. The rotation mechanism 209 shown in this figure is equipped with a support plate 209A having an arc-shaped guide groove GH formed therein, and a connecting jig 209B consisting of a combination of bolts and nuts. This support plate 209A is fixed to a base 400, for example, and one of the drilling columns 201 is pin-connected to the base 400 or support plate 209A at its lower end. The drilling column 201 is also provided with bolt holes at positions corresponding to the guide groove GH. When the drilling column 201 is rotated after inserting bolts (connecting jig 209B) through the bolt holes and guide groove GH, the drilling column 201 can rotate while being guided by the guide groove GH. Furthermore, by rotating the drilling support column 201 by a desired inclination angle (e.g., 45 degrees) and then screwing a nut (connecting jig 209B) onto the bolt (connecting jig 209B) and tightening it, the inclination angle of the drilling support column 201 can be maintained. In other words, the connecting jig 209B (bolt and nut) that clamps and tightens the drilling support column 201 and the support plate 209A functions as a stopper to support the inclined drilling support column 201.

[0034] (slider) The slider 202, which constitutes the drilling means 200, is attached to the drilling column 201 and also supports the rotary drive unit 203. In other words, the rotary drive unit 203 is attached to the drilling column 201 via the slider 202. However, the slider 202 is attached to the drilling column 201 so that it can slide along the column axis direction (i.e., vertical direction) of the drilling column 201. As a result, even as drilling progresses, the rotary drive unit 203 can slide downward without any particular resistance.

[0035] Various conventional techniques can be used to move the slider 202 along the column axis direction of the drilling column 201. For example, the slider 202 can be moved by a combination of a chain and pulley, or by a combination of a motor and tires. Alternatively, as shown in Figure 2, a rack and pinion mechanism consisting of a sliding rack 201A and a sliding gear 202A can be used. The sliding rack 201A is attached to the front side (right side in the figure) of the drilling column 201 along the column axis direction (i.e., vertical direction), and the sliding gear 202A is attached to the slider 202. Then, with the sliding gear 202A meshed with the sliding rack 201A, the slider 202 is moved by operating the lever block (registered trademark) 202B shown in Figure 5.

[0036] (Rotating drive unit) Figure 5 is a side view showing the rotary drive unit 203, which constitutes the drilling means 200, attached to the slider 202. This rotary drive unit 203 rotates the drilling rod 205 to form the test hole TH. While various conventional technologies can be used as the rotary drive unit 203 as long as they can rotate the drilling rod 205, for convenience, this explanation will use a core drill as the rotary drive unit 203. This core drill includes a motor driven by electricity and a rotating shaft (hereinafter specifically referred to as "drill rotating shaft 203A") that rotates at high speed by this motor. It can be manufactured as a dedicated unit, or existing products already available on the market (commercially sold or leased) can be used. For example, the "Dymo Drill TS-165" or "Dymo Drill TS-405" manufactured by Shibuya Co., Ltd. can be used. However, a commonly used core bit is not used, and a reduction gear 204 is connected to the drill rotating shaft 203A.

[0037] (Deceleration body) As previously mentioned, core drills rotate at high rotational speeds (revolutions per unit time). For example, the Dymo Drill TS-165 has a rotational speed of 1000 / 700 rpm, and the Dymo Drill TS-405 has a rotational speed of 700 / 300 rpm. On the other hand, when drilling into relatively hard ground, considerable torque is required, in which case the drilling rod is rotated at a low speed. For example, conventional rotary boring machines rotated the drilling rod at around 100-50 rpm. In other words, when using a core drill, the drilling rod rotates at such high speed that it may not be possible to properly drill into the ground. In such cases, it is advisable to use a reduction gear 204 to reduce the rotational speed of the rotary drive unit 203 (core drill).

[0038] Figure 6 shows a reduction gear 204 that constitutes the drilling means 200, where (a) is a cross-sectional view showing the assembled parts and (b) is an exploded view showing the parts that make up the reduction gear 204. As shown in this figure, the reduction gear 204 is composed of a reduction gear body 204A, and can also be composed of an upper flange 204B, a lower flange 204C, a coupler 204D which is a connecting jig, a water supply mechanism 208, etc. Of these, the water supply mechanism 208 supplies drilling water injected from the outside into the drilling rod 205, as will be described later, and is composed of a water swivel 208A and a water injection ring 208B.

[0039] The upper flange 204B and lower flange 204C stably support the reducer body 204A by clamping it from above and below. Part of the reducer body 204A rotates together with the drill rotation shaft 203A, but the rotation is restricted by the upper flange 204B and lower flange 204C. Although Figure 6 uses a single-stage reducer body 204A, it is not limited to this configuration and two or more stages of reducer bodies 204A can be stacked and used. The coupler 204D, which is inserted into the upper flange 204B, is connected to the drill rotation shaft 203A at its upper end and to the reducer body 204A at its lower end. However, depending on the structure of the drill rotation shaft 203A, it is also possible to connect the drill rotation shaft 203A directly to the reducer body 204A without using the coupler 204D.

[0040] The gearbox body 204A reduces the rotation of the drill rotation shaft 203A and then transmits the rotation to the lower rotating system (water swivel 208A, drilling rod 205, core tube 206, etc.). More specifically, the gearbox body 204A transmits rotation to the drilling rod 205, etc., at a rotational speed lower than the rotational speed input from the drill rotation shaft 203A and with a torque greater than the torque input from the drill rotation shaft 203A.

[0041] As long as the reduction gear body 204A can reduce the rotation of the drill rotation shaft 203A and transmit that rotation to the lower rotation system, various conventional reduction gears can be used. For example, a reduction gear body 204A using the planetary gear mechanism shown in Figure 7 can be adopted. In this case, the reduction gear body 204A consists of a sun gear GS, multiple (four in the figure) planetary gears GP, an internal gear GR, and a planetary carrier (not shown), as shown in the figure, with the sun gear GS and planetary gears GP positioned inside the internal gear GR. The planetary gears GP are also positioned to mesh with the gears of the internal gear GR and the sun gear GS, respectively. A coupler 204D connected to the drill rotation shaft 203A is connected to the sun gear GS, and the planetary carriers connected to the multiple planetary gears GP are connected to the drilling rod 205. As mentioned above, it is also possible to directly connect the drill rotation shaft 203A to the sun gear GS without using the coupler 204D. Alternatively, instead of directly connecting the planetary carrier to the drilling rod 205, as shown in Figure 6, the planetary carrier can be connected to a water swivel 208A (connecting jig), and the drilling rod 205 can then be connected to the lower part of the water swivel 208A.

[0042] The internal gear GR is fixed in such a way that its rotation is constrained (restricted). On the other hand, the sun gear GS rotates in conjunction with the rotation of the drill rotation shaft 203A, and the planetary gear GP and planetary carrier also rotate in conjunction with the rotation of the sun gear GS. As a result, the planetary carrier rotates at a rotational speed lower than the rotational speed input from the drill rotation shaft 203A, and consequently, the drilling rod 205 also rotates at a lower speed than the drill rotation shaft 203A.

[0043] Although the rotary drive unit 203 rotates at high speed, it is supported by the slider 202, so no large oscillations occur. On the other hand, the reduction gear 204 is only connected to the drill rotation shaft 203A, and it is possible that it may oscillate significantly with the high-speed rotation of the rotary drive unit 203, which could endanger the operator. Therefore, in cases where large oscillations of the reduction gear 204 are expected, it is advisable to provide a stopper mechanism on the reduction gear 204. For example, in Figure 8, a stopper mechanism consisting of a left arm 204E, a right arm 204F, and a connecting bar 204G is provided on the reduction gear 204. The left arm 204E and the right arm 204F are fixed to a part of the reduction gear 204 (for example, the internal gear GR, the upper flange 204B, and the lower flange 204C) so as to extend upward, and the connecting bar 204G, positioned between them, connects and supports the left arm 204E and the right arm 204F. Then, by sandwiching the slider 202 and the rotary drive unit 203 between the left arm 204E and the right arm 204F, the oscillation of the reduction unit 204 is suppressed.

[0044] (Drilling rod) The drilling rod 205 that constitutes the drilling means 200 is a rod that has been used in conventional boring and other applications, and can be a product that is already available on the market (commercially available or leased). The upper part of the drilling rod 205 is directly connected to a part of the rotary drive unit 203 (for example, the drill rotation shaft 203A), or indirectly connected via a coupler as a connecting jig. However, if the drilling means 200 is equipped with a reduction gear 204, the upper part of the drilling rod 205 is directly connected to a part of the reduction gear 204 (for example, the planetary carrier), or indirectly connected to a part of the reduction gear 204 (for example, the planetary carrier) via a coupler as a connecting jig or a water swivel 208A. It is also possible to attach a bit to the tip of the drilling rod 205 and drill into the ground, or to attach a core tube 206 to the tip of the drilling rod 205 and drill into the ground while collecting ground samples (cores).

[0045] (Water supply mechanism) The water supply mechanism 208, which constitutes the drilling means 200, supplies drilling water to the drilling rod 205 during drilling, and is composed of a water swivel 208A and a water injection ring 208B. The hollow, generally columnar water swivel 208A is connected to a part of the reduction body 204 (e.g., a planetary carrier) and rotates together with the drill rotation shaft 203A, transmitting rotation to the drilling rod 205 connected at its lower end. In contrast, the annular water injection ring 208B is connected to a part of the reduction body 204 (e.g., a lower flange 204C) and its rotation is restricted.

[0046] Figure 9 is a schematic perspective view of the water swivel 208A. As shown in this figure, a water passage hole WP is provided on the side of the water swivel 208A. The water swivel 208A also has a ring-shaped water retention groove GT that is slightly recessed from the surrounding side, and the water passage hole WP is provided within this water retention groove GT. In other words, the water passage hole WP opens at a position slightly recessed from the side. On the other hand, as shown in Figure 6(a), a water injection hole WE is provided on the side of the water injection ring 208B. This water injection ring 208B is extrapolated onto the water swivel 208A so as to cover the water retention groove GT, and as a result, a donut-shaped closed space (hereinafter referred to as the "water storage space") is formed by the inner wall of the water injection ring 208B and the water retention groove GT.

[0047] The mechanism by which drilling water is supplied to the drilling rod 205 during drilling is described below. When water is pumped from a water tank using a submersible pump or the like, it is sent into the water injection ring 208B through the water injection hole WE connected to a hose or the like. Next, the water flows through the side wall of the water injection ring 208B and is sent into the water swivel 208A, where it is stored in the water reservoir. Then, water entering from the water passage hole WP flows through the water swivel 208A and is supplied to the drilling rod 205 as drilling water. At this time, water is stored in the water reservoir, so water is always supplied to the water passage hole WP even while the water swivel 208A is rotating, and therefore drilling water is always supplied to the drilling rod 205 during drilling. Note that in cases where so-called "waterless drilling," where no drilling water is used, is possible, the drilling means 200 does not necessarily need to be equipped with a water supply mechanism 208.

[0048] (Strut support means) As shown in Figure 2, the drilling means 200 can drill with the drilling column 201 standing upright. On the other hand, if the rotary drive unit 203 rotates at a considerably high speed, the drilling column 201 may oscillate during drilling, resulting in vibration in the drilling rod 205, which may prevent the formation of a proper test hole TH, or even create a situation that could endanger the worker. In such cases, it is preferable to support the drilling column 201 during drilling with the column support means 207, as shown in Figure 1.

[0049] Figure 10 is a schematic diagram of the support column means 207 that constitutes the drilling means 200, where (a) is a side view showing the individual parts of the disassembled support column means 207, and (b) is a side view showing the situation in which the support column means 207 connected to the test column 301 supports the drilling column 201. The support column means 207 shown in this figure consists of a first arm 207A and a second arm 207B, with one end of the first arm (right end in the figure) and one end of the second arm 207B (left end in the figure) being pin-connected. The other end of the first arm 207A (left end in the figure) is pin-connected to the test column 301. As a result, the first arm 207A rotates around a substantially horizontal (including horizontal) axis, and the second arm 207B also rotates around a substantially horizontal (including horizontal) axis. Therefore, unless any special operation is performed, the first arm 207A and the second arm 207B will be in a state of hanging vertically downward, as shown in Figure 3.

[0050] On the other hand, when the drilling column 201 is supported by the column support means 207, as shown in Figure 10(b), the first arm 207A is rotated to be positioned approximately horizontal (including horizontal), and the second arm 207B is rotated to be positioned approximately vertical (including vertical) downward. Then, the narrow diameter portion formed at the lower end of the second arm 207B is inserted into the upper part of the drilling column 201. In this way, the drilling column 201 is supported by the column support means 207, and even if the rotary drive unit 203 rotates at a considerably high speed, the oscillation of the drilling column 201 during drilling can be suppressed.

[0051] 1-2. Test Methods Next, the test means 300 that constitute the ground testing apparatus 100 of the present invention will be described. This test means 300 can perform various in-situ tests such as conical penetration tests, Swedish sounding tests, vane tests, and in-situ loading tests, but for convenience, the example in which the test means 300 performs a standard penetration test will be described here.

[0052] As shown in Figure 3, the test means 300 consists of a test support 301, a guide rod 307, a hammer 308 (drive hammer), a knocking head 309 (anvil), a test rod 310, and a sampler 311. It can also be further composed of a pulley beam 302, a rope 304, a winch with a pulley 305, a small engine 306, a rod puller, a counterweight, and the like.

[0053] The test support column 301, which constitutes the test means 300, is a hollow or solid columnar member, with its axis approximately vertical (including vertical) and its legs fixed to the base 400. A pulley beam 302, positioned approximately horizontally (including horizontal), is attached to the top of the test support column 301, and pulleys 303 are provided at its front and rear. A rope or other material 304 is wound around the front and rear pulleys 303, and a hammer 308 (especially a catcher) is attached to the lower front end (right side in the diagram) of the rope 304, while the lower rear end (left side in the diagram) is wound around the pulley of a pulley-equipped winch 305. This pulley-equipped winch 305 winds in and out the rope 304, and a small engine 306 powers the pulley-equipped winch 305. The rod extraction machine uses a hydraulic jack or the like to extract the test rod 310 and the drilling rod 205. The ground testing apparatus 100 of the present invention can also employ a conventionally used three-pronged scaffold instead of the temporary equipment described above.

[0054] The guide rod 307, hammer 308, knocking head 309, test rod 310, and sampler 311 that constitute the test means 300 can be equipment specified in "JIS A 1219". Of these, the guide rod 307 is supported by an arm installed on the test support column 301, with the column axis being approximately vertical (including vertical). The hammer 308 is inserted through the guide rod 307, and the knocking head 309 is attached to its lower end. The test rod 310 is attached below the knocking head 309, and the sampler 311 is attached to the lower end of the test rod 310.

[0055] The procedure for conducting a standard penetration test using the test means 300 is described below. First, drilling is performed using the drilling means 200, and once the test hole TH is formed to a predetermined depth, the drilling rod 205 is withdrawn, for example, by a rod extraction machine, and the drilling means 200 is moved to a position away from the test hole TH. At this time, since it is equipped with a rotating mechanism 209, it can be easily moved simply by rotating the drilling support column 201.

[0056] When the drilling device 200 is moved, preparations for the standard penetration test are made. Specifically, the hammer 308 is inserted through the guide rod 307, and a knocking head 309 is attached to its lower end. A test rod 310 is attached below the knocking head 309, and a sampler 311 is attached to the lower end of the test rod 310. The sampler 311 is then lowered to the bottom of the test hole TH and allowed to sink on its own. A "preliminary run" is performed in which the 63.5 kg hammer 308 is repeatedly dropped from a height of 760 mm ± 10 mm until the sampler 311 penetrates 150 mm. After the preliminary run, a "main run" is performed in which the 63.5 kg hammer 308 is repeatedly dropped from a height of 760 mm ± 10 mm until the sampler 311 penetrates 300 mm, and the N value is recorded every 100 mm of depth. After the sampler 311 penetrates 300 mm, a 5 cm "post-penetration" is performed, the sampler 311 is withdrawn, the shoe and coupling are removed, and the split barrel is cut in two to observe the collected sample, and a representative sample is stored in a transparent container. Then, drilling is performed again with the drilling means 200 to form the test hole TH, the drilling means 200 is moved, and the standard penetration test is performed.

[0057] 2. Soil Testing Methods Next, the ground testing method of the present invention will be explained with reference to Figure 11. The ground testing method of the present invention is a method of performing in-situ tests on the ground using the ground testing device 100 described so far. Therefore, explanations that overlap with those described for the ground testing device 100 will be avoided, and explanations will mainly focus on those specific to the ground testing method of the present invention. In other words, anything not described here is the same as what was described in "1. Ground Testing Device".

[0058] Figure 11 is a flowchart showing the main steps of the ground testing method of the present invention. As shown in this figure, first a base 400 is placed on the ground (Step 10 in Figure 11), the drilling means 200 is assembled (Step 20 in Figure 11), and a part of the testing means 300 is assembled (Step 30 in Figure 11). When assembling the drilling means 200, the drilling column 201 is attached to the base 400 so as to rotate around a substantially horizontal axis (Step 21 in Figure 11), the slider 202 with a rotary drive unit 203 attached is attached to the drilling column 201, the reduction body 204 is attached to the rotary drive unit 203, and then the drilling rod 205 and core tube 206 are attached (Step 22 in Figure 11).

[0059] On the other hand, when assembling the test device 300, the test support column 301, whose column axis is approximately vertical, is fixed to the base 400 at its legs (Step 31 in Figure 11). Next, a winch with pulley 305, a small engine 306, a rod puller, a counterweight, etc. are installed on the base 400, and the rope material 304 is wound around the pulley of the winch with pulley 305, and then wound around the pulley 303 of the pulley beam 302 (Step 32 in Figure 11). At this time, it is advisable to attach a guide rod 307 to the arm installed on the test support column 301.

[0060] After assembling the drilling means 200 and the testing means 300, drilling is performed by the drilling means 200 to form a test hole TH to a predetermined depth (Step 40 in Figure 11). Then, for example, the drilling rod 205 is pulled out using a rod puller, and the drilling support column 201 is rotated to move the drilling means 200 to a position away from the test hole TH (Step 50 in Figure 11).

[0061] As the drilling mechanism 200 is moved, the hammer 308 is inserted through the guide rod 307, and the hammer 308 (especially the catcher) is attached to the lower end of the guide rod 304. Then, the knocking head 309 is attached to the lower end of the guide rod 307, the test rod 310 is attached below the knocking head 309, and the sampler 311 is attached to the lower end of the test rod 310 (Step 60 in Figure 11). Once these preparations are complete, a standard penetration test is performed over one section (usually 50 cm) (Step 70 in Figure 11).

[0062] The work is terminated when the test borehole TH reaches the planned depth or when the planned supporting ground is confirmed (Yes in Step 80 of Figure 11). On the other hand, when conducting a standard penetration test at a deeper location (No in Step 80 of Figure 11), the series of steps consisting of drilling one section (Step 40) to conducting a standard penetration test for one section (Step 70) is repeated. [Industrial applicability]

[0063] The ground testing apparatus and ground testing method of the present invention can be used for standard penetration tests to understand the conditions of the ground (determination of hardness, compaction, and soil layer composition), and can be particularly effective for standard penetration tests conducted in locations where it is difficult to transport equipment, such as test sites in mountainous areas. [Explanation of Symbols]

[0064] 100 Ground testing apparatus of the present invention 200 Drilling means (of the ground testing device) 201 Drilling support (for drilling means) 201A (Drilling support) sliding rack 202 Slider (of drilling means) 202A (Slider) Gear for Slide 202B (Slider) Lever Block (Registered Trademark) 203 Rotary drive body (of drilling means) 203A (Drill rotation shaft of a rotary drive unit) 204 (Drilling mechanism) speed reducer 204A (Reduction Gear) Reducer Body 204B (Upper flange of the speed reducer) 204C (lower flange of the speed reducer) 204D (Reduction Gear) Coupler 204E (Speed ​​reducer) left arm 204F (Speed ​​reducer) Right arm 204G (deceleration unit) connecting bar 205 Drilling rod (of drilling means) 206 Core tube (of drilling means) 207 (Drilling means) Support column means 207A First arm (of the support means) 207B Second arm (of the support means) 208 Water supply mechanism (of drilling means) 208A (Water supply mechanism) Water swivel 208B (Water supply mechanism) water injection ring 209 Rotation mechanism (of drilling means) 209A Support plate (for the rotating mechanism) 209B (Rotating mechanism) connecting jig 300 Testing methods (for ground testing equipment) 301 Test support (of a test device) 302 Pulley beam (of the test means) 303 Pulley (of the test means) 304 (Test method) materials 305 (Testing device) Winch with pulley 306 Small engine (of test equipment) 307 Guide rod (of the test method) 308 (Testing tool) Hammer 309 (Test method) Knocking head 310 Test rod (of a test method) 311 Sampler (of a test device) 400 (base of the ground testing equipment) 401 (Base) Base anchor GH (support plate) guide groove GP (planetary gear of the gearbox) GR (Internal gear of the gearbox) GS (Sun gear of the gearbox) GT (Water Swivel) Water Retention Channel TH test hole WE (water inlet ring) water inlet hole WP (water swivel) water passage hole

Claims

1. A base installed on the ground, A drilling support column is attached to the base so as to be rotatable around a horizontal or substantially horizontal axis, A slider is attached to the drilling support so as to move in the axial direction of the drilling support, A rotary drive unit attached to the slider, A drilling rod connected to the aforementioned rotary drive body, Equipped with testing methods, With the drilling support columns positioned vertically or approximately vertically, the rotary drive unit rotates the drilling rod to form a test hole in the ground. By rotating the drilling support column to which the rotary drive body is attached around a horizontal or substantially horizontal axis, the rotary drive body is moved to a position away from the test hole, thereby enabling the test to be performed using the test hole and the test means. A ground testing apparatus characterized by the following features.

2. The system further includes a stopper for fixing the drilling support column, which is tilted by rotating around a horizontal or substantially horizontal axis. The ground testing apparatus according to claim 1, characterized in that it is a ground testing apparatus.

3. The test means comprises a test column positioned vertically or substantially vertically and fixed to the base; a hammer inserted through a guide rod and falling along the guide rod; a knocking head connected to the lower end of the guide rod; and a test rod connected to the knocking head. Using the aforementioned test hole, a standard penetration test can be performed using the aforementioned test means. The ground testing apparatus according to claim 1, characterized in that it is a ground testing apparatus.

4. The system further comprises a support means for the test column, which includes a first arm pin-connected to the test column and a second arm pin-connected to the first arm. When the first arm, which rotates around a horizontal or substantially horizontal axis, is positioned horizontally or substantially horizontally, and the second arm, which rotates around a horizontal or substantially horizontal axis, is positioned vertically or substantially vertically, the lower end of the second arm and the upper end of the drilling support column, which is positioned vertically or substantially vertically, are connected. With the drilling support column supported by the support column support means, the drilling rod can be rotated. The ground testing apparatus according to claim 3, characterized in that it is as described above.

5. A method for conducting ground tests using a ground testing device, The aforementioned ground testing apparatus comprises a base, a drilling support column, a slider, a rotary drive unit, a drilling rod, and testing means. A support installation step involves installing the base on the ground and attaching the drilling support to the base so that it can rotate around a horizontal or substantially horizontal axis, The equipment installation process involves attaching the slider to which the rotary drive body is attached to the drilling support column, and connecting the drilling rod to the rotary drive body. The drilling process involves rotating the drilling rod with the aforementioned rotary drive unit to form a test hole in the ground, The drilling means moving step includes moving the drilling support column, to which the rotary drive body is attached, to a position away from the test hole by rotating the drilling support column around a horizontal or substantially horizontal axis, After the drilling means movement step, the test can be performed using the test hole and the test means. A ground testing method characterized by the following features.

6. The ground testing apparatus comprises a test support column positioned vertically or substantially vertically and fixed to the base, a hammer inserted through a guide rod and falling along the guide rod, a knocking head connected to the lower end of the guide rod, and a test rod connected to the knocking head. Once a predetermined depth is reached by the drilling process, a standard penetration test can be performed using the test means after the drilling means movement process. The ground testing method according to claim 5, characterized in that it is a feature of the present invention.

7. In the drilling process, the drilling rod, to which a core tube is connected at its lower end, is rotated, and a core is drilled into the core tube while collecting a core sample. The ground testing method according to claim 5, characterized in that it is a feature of the present invention.

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