Dynamic compaction foundation quality detection sampling method

Abstract

The invention belongs to the technical field of dynamic compaction foundations, discloses a dynamic compaction foundation quality detection sampling method, and aims to solve the problem that a core sample is easily damaged when the core sample of the dynamic compaction foundation is obtained by adopting an existing coring bit. The method comprises the following steps: (1) cutting and drilling an outer-layer soil body by using outer-layer cutting teeth on an outer cutting cylinder; (2) inner-layer cutting teeth on an inner cutting cylinder are used for cutting and drilling an inner-layer soil body; (3) synchronously driving a protective cylinder for coating the core sample to move downwards; (4) when the lower end surface of the protective cylinder moves to a designed depth, cutting a soil body below the core sample by using a cutting blade; and (5) taking out the protective cylinder from the inner cutting cylinder, and opening the protective cylinder to obtain a core sample of the dynamic compaction foundation. According to the invention, disturbance to the dynamic compaction foundation core sample can be reduced, and the core sample forming quality is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of dynamic compaction foundation, and particularly relates to a sampling method for quality inspection of dynamic compaction foundation. Background Art

[0002] For foundations treated by methods such as replacement, preloading, compaction, densification, dynamic compaction, grouting, etc., soil (rock) foundation load tests should be carried out. For dynamic compaction foundations, in addition to using foundation load tests, standard penetration tests, cone penetration tests, static penetration tests, etc. can also be used. During the dynamic compaction process of a dynamic compaction foundation, backfilling and dynamic compaction are generally carried out in layers. Therefore, no matter which detection method is used, it is impossible to obtain the internal situation of the dynamic compaction foundation well.

[0003] In the prior art, a core bit is used to take the core sample of the dynamic compaction foundation, and the true situation inside the dynamic compaction foundation is obtained by analyzing the core sample. However, the current core bit has a large disturbance to the core sample during use. Coupled with the layering problem of the dynamic compaction foundation, when using a core gripper to grab the core sample of the dynamic compaction foundation, it is extremely easy for the core sample to be damaged and unable to reflect the true situation of the dynamic compaction foundation. Summary of the Invention

[0004] The present invention provides a sampling method for quality inspection of dynamic compaction foundation in order to solve the problem that the core sample is easily damaged when using the existing core bit to obtain the core sample of the dynamic compaction foundation.

[0005] In order to solve the technical problem, the technical solution adopted by the present invention is: A sampling method for quality inspection of dynamic compaction foundation, characterized by comprising: (1) Driving the outer cutting cylinder to rotate, so as to cut and drill the outer soil layer by using the outer cutting teeth on the outer cutting cylinder; (2) After the outer cutting cylinder cuts and drills for a certain distance, the inner cutting teeth on the inner cutting cylinder cut and drill the inner soil layer. The cutting width of the outer cutting teeth is greater than the cutting width of the inner cutting teeth, and the rotation direction of the outer cutting cylinder is opposite to the rotation direction of the inner cutting cylinder; (3) During the drilling process, the inner cutting cylinder synchronously drives the protection cylinder for covering the core sample of the dynamic compaction foundation to move downward, so that the protection cylinder can be sleeved around the core sample. There is a distance between the lower end surface of the protection cylinder and the lower end surface of the inner cutting cylinder; and during the cutting and drilling process, the inner cutting teeth on the inner cutting cylinder can cut the soil at the lower end of the protection cylinder; (4) When the lower end surface of the protection cylinder moves to the designed depth, a cutting blade hidden at the bottom of the outer cutting cylinder extends towards the core sample of the dynamic compaction foundation. The cutting blade is located at the lower end of the inner cutting cylinder, and the cutting blade extends to the axis of the core sample to cut the soil below the core sample; (5) Pull out the outer cutting cylinder, the inner cutting cylinder, and the protection cylinder as a whole from the drilled hole, take out the protection cylinder from the inner cutting cylinder, and then open the protection cylinder to obtain the core sample of the dynamic compaction foundation.

[0006] In some embodiments, the protection cylinder can rotate along the inner cutting cylinder; when the friction force between the protection cylinder and the core sample is less than the friction force between the protection cylinder and the inner cutting cylinder, the protection cylinder gradually sleeves around the core sample in a spiral manner; when the friction force between the protection cylinder and the core sample is greater than the friction force between the protection cylinder and the inner cutting cylinder, the protection cylinder does not rotate.

[0007] In some embodiments, a step is provided on the inner wall of the inner cutting cylinder, the lower end of the protection cylinder is placed on the step, a pressure rod is rotatably connected to the upper end of the inner cutting cylinder, a roller is installed below the pressure rod, and the upper end of the protection cylinder is in contact with the inner cutting cylinder through the roller.

[0008] In some embodiments, the cutting blade extends out of the outer cutting cylinder from the lower end face of the inner cutting cylinder.

[0009] In some embodiments, when cutting the bottom of the core sample, adjust the length of the cutting blade extending out of the outer cutting cylinder, and cut the bottom of the core sample in a multi-cut manner.

[0010] In some embodiments, a convex platform is formed on the outer cutting cylinder, a chute is provided in the convex platform, the cutting blade is mutually adapted to the chute, a vertical groove is provided on the outer cutting cylinder along the height direction, the vertical groove communicates with the chute, a pulley is installed at the position where the vertical groove communicates with the chute, a vertical slider is installed in the vertical groove, one end of the cutting blade facing the inner bottom of the chute is connected with a traction belt, and the other end of the traction belt bypasses the pulley and is connected with the vertical slider.

[0011] In some embodiments, a strip-shaped through hole is provided on the outer cutting cylinder along the height direction, a threaded hole is provided on the vertical slider, and the threaded hole is provided with a locking screw and a locking nut.

[0012] In some embodiments, the outer cutting teeth of the outer cutting cylinder and the inner cutting teeth of the inner cutting cylinder have a partially overlapping area in the vertical projection.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The sampling method of the present invention first uses the outer cutting teeth on the outer cutting cylinder to drill, thereby forming a hole with a relatively large size. After the outer cutting cylinder cuts and drills for a certain distance, the inner cutting cylinder cuts the soil body to achieve layered cutting of the core sample. That is, a large core sample is cut by the outer cutting teeth, and then the large core sample is cut in a small range by the inner cutting teeth, and finally a core sample of the dynamic compaction foundation that is mutually adapted to the size of the protection cylinder is obtained. The present invention adopts a method of gradually cutting the soil body in layers. Compared with the existing method of forming a core sample by one-time drilling of a core bit, the cutting amount of the inner cutting teeth close to the protection cylinder is relatively small, so the disturbance to the core sample of the dynamic compaction foundation is also relatively small. At the same time, the rotation directions of the inner cutting cylinder and the outer cutting cylinder are opposite, and a part of the rotational inertia generated when the inner cutting cylinder and the outer cutting cylinder rotate can cancel each other out, so as to further reduce the disturbance to the core sample and improve the quality of the core sample.

[0014] Moreover, when the cutting blade of the present invention cuts the bottom of the core sample, since there is still a distance between the lower end of the protection cylinder and the cutting blade, and the bottom of the actually required core sample corresponds to the bottom of the protection cylinder, the influence of the cutting blade on the bottom of the actually required core sample during the cutting process is relatively small, further improving the quality of the core sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic structural diagram of an embodiment of the outer cutting cylinder and the inner cutting cylinder of the present invention; Figure 2 is Figure 1 a schematic diagram of a partial enlarged view at position A in Figure 3 is Figure 1 a schematic diagram of a partial enlarged view at position B in Figure 4 is Figure 1 a schematic diagram of a partial enlarged view at position C in Figure 5 is Figure 1 a schematic diagram of a partial enlarged view at position D in Figure 6 It is a schematic structural diagram of an embodiment of the protection cylinder of the present invention; Markings in the figure: 1. Outer cutting cylinder, 101. Outer cutting teeth, 102. Cutting blade, 103. Chute, 104. Vertical groove, 105. Traction belt, 106. Vertical slider, 2. Inner cutting cylinder, 201. Inner cutting teeth, 202. Annular groove, 203. Step, 204. Ball, 205. Pressure rod, 206. Roller, 3. Protection cylinder, 4. Bearing, 5. Outer bearing block, 6. First connecting rod, 7. Inner bearing block, 8. Second connecting rod, 9. Installation platform, 10. Connector. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] The present invention will be further described below in conjunction with embodiments. The described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0017] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention; the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance; in addition, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0018] Combined with the drawings, the method for sampling and testing the quality of a dynamic compaction foundation of the present invention includes: (1) Drive the outer cutting cylinder 1 to rotate, so as to cut and drill the outer soil layer by using the outer cutting teeth 101 on the outer cutting cylinder 1.

[0019] (2) After the outer cutting cylinder 1 cuts and drills for a certain distance, the inner cutting teeth 201 on the inner cutting cylinder 2 cut and drill the inner soil layer. The cutting width of the outer cutting teeth 101 is greater than the cutting width of the inner cutting teeth 201, and the rotation direction of the outer cutting cylinder 1 is opposite to the rotation direction of the inner cutting cylinder 2. Among them, the rotation directions of the inner cutting cylinder 2 and the outer cutting cylinder 1 are opposite, and the rotational inertia generated when the inner cutting cylinder 2 and the outer cutting cylinder 1 rotate can offset each other to a certain extent, so as to further reduce the disturbance to the core sample and thus improve the quality of the core sample.

[0020] (3) During the drilling process, the inner cutting cylinder 2 synchronously drives the protection cylinder 3 for covering the core sample of the dynamic compaction foundation to move downward, so that the protection cylinder 3 can be sleeved around the core sample. There is a distance between the lower end surface of the protection cylinder 3 and the lower end surface of the inner cutting cylinder 2; and during the cutting and drilling process of the inner cutting cylinder 2, the inner cutting teeth 201 can cut the soil at the lower end of the protection cylinder 3. That is to say, the protection cylinder 3 can move downward together with the inner cutting cylinder 2, and at the same time, the inner cutting teeth 201 can cut the soil at the lower end surface of the protection cylinder 2 to ensure that the protection cylinder 3 does not participate in cutting the soil.

[0021] (4)When the lower end face of the protection cylinder 3 moves to the designed depth, a cutting blade 102 hidden at the bottom of the outer cutting cylinder 1 extends towards the core sample of the dynamic compaction foundation. The cutting blade 102 is located at the lower end of the inner cutting cylinder 2, and the cutting blade 102 extends to the axis of the core sample to cut the soil body below the core sample. (5)The outer cutting cylinder 1, the inner cutting cylinder 2 and the protection cylinder 3 are integrally pulled out from the drilled hole, and the protection cylinder 3 is taken out from the inner cutting cylinder 2, and then the protection cylinder 2 is opened to obtain the core sample of the dynamic compaction foundation. In the specific implementation process, since there is a certain distance between the bottom surface of the inner cutting cylinder 2 and the bottom of the outer cutting cylinder, when the entire outer cutting cylinder 1 and the inner cutting cylinder 2 are taken out synchronously, the cutting blade 102 is retracted (that is, the cutting blade 102 is hidden in the outer cutting cylinder 1 again) to expose the lower bottom of the core sample, and the soil body between the bottom of the inner cutting cylinder 2 and the bottom of the outer cutting cylinder is manually cut (that is, the soil body that has not been cut by the inner layer cutting teeth 201 and the outer layer cutting teeth 101 below the protection cylinder 3 is cut), so that the size of the entire core sample is the same as the inner diameter of the protection cylinder 3, which is convenient for smoothly taking out the protection cylinder 3 from the inner cutting cylinder 2.

[0022] Preferably, the outer layer cutting teeth 101 of the outer cutting cylinder 1 and the inner layer cutting teeth 201 of the inner cutting cylinder 2 have a partially overlapping area in the vertical projection, so as to avoid the problem that the soil body in the area between the inner cutting cylinder and the outer cutting cylinder is not cut and drilled.

[0023] The sampling method of the present invention first uses the outer layer cutting teeth on the outer cutting cylinder to drill, so as to form a hole with a larger size. After the outer cutting cylinder cuts and drills for a certain distance, the inner cutting cylinder cuts the soil body to realize the layered cutting of the core sample. That is, a large core sample is cut by the outer layer cutting teeth, and then the large core sample is cut in a small range by the inner layer cutting teeth, and finally a core sample of the dynamic compaction foundation that matches the size of the protection cylinder is obtained. The present invention adopts a method of cutting the soil body in a layered and progressive manner. Compared with the existing core drill bit that forms a hole in one drilling, the cutting amount of the inner layer cutting teeth close to the protection cylinder is relatively small, so the disturbance to the core sample of the dynamic compaction foundation is also relatively small; at the same time, the rotation directions of the inner cutting cylinder and the outer cutting cylinder are opposite, and the rotational inertia generated when the inner cutting cylinder and the outer cutting cylinder rotate can offset each other to further reduce the disturbance to the core sample, thereby improving the quality of the core sample.

[0024] Moreover, when the cutting blade of the present invention cuts the bottom of the core sample, since there is still a spacing between the lower end of the protection cylinder and the cutting blade, and the bottom of the actually required core sample corresponds to the bottom of the protection cylinder, the cutting blade has less impact on the bottom of the actually required core sample during the cutting process, further improving the quality of the core sample. In the prior art, when the coring bit samples with coring claws, the way of grabbing by the coring claws has a large disturbance to the core sample of the dynamic compaction foundation, and even seriously damages the periphery and bottom of the core sample, resulting in poor forming quality of the core sample.

[0025] In some embodiments, the protection cylinder 3 can rotate along the inner cutting cylinder 2; when the friction force between the protection cylinder 3 and the core sample is less than the friction force between the protection cylinder 3 and the inner cutting cylinder 2, the protection cylinder 2 gradually sleeves on the periphery of the core sample in a spiral manner; when the friction force between the protection cylinder 3 and the core sample is greater than the friction force between the protection cylinder 3 and the inner cutting cylinder 2, the protection cylinder 3 does not rotate. When the protection cylinder 3 does not rotate, the protection cylinder 3 directly follows the inner cutting cylinder 2 and moves downward to directly sleeve on the periphery of the core sample; thus preventing the core sample from being damaged due to the rotation of the protection cylinder 3, further reducing the disturbance to the core sample, and improving the forming quality of the core sample.

[0026] In the specific implementation process, at least two annular grooves 202 are provided on the inner wall of the inner cutting cylinder 2 along the height direction, bearings 4 are embedded in the annular grooves 202, and the protection cylinder 3 is sleeved in the bearings 4 to realize the rotational connection between the inner cutting cylinder 2 and the protection cylinder 3.

[0027] Among them, the inner cutting cylinder 2 is spliced in multiple sections to facilitate the installation of the bearings 4.

[0028] In some embodiments, a step 203 is provided on the inner wall of the inner cutting cylinder 2, the lower end of the protection cylinder 3 is placed on the step 203, a pressure rod 205 is rotatably connected to the upper end of the inner cutting cylinder 2, a roller 206 is installed below the pressure rod 205, and the upper end of the protection cylinder 3 is in contact with the inner cutting cylinder 2 through the roller 206. When the pressure rod 205 is rotated so that the roller 206 contacts the protection cylinder 3, the protection cylinder 3 is clamped between the step 203 of the inner cutting cylinder 2 and the pressure rod 205, thus facilitating the installation of the protection cylinder. When the protection cylinder 3 needs to be removed, the pressure rod 205 is rotated so that the roller 206 does not contact the protection cylinder 3, the upper end of the protection cylinder 3 is unobstructed, and the protection cylinder 3 can be directly removed from the inner cutting cylinder 2, thus facilitating the removal of the protection cylinder 3. In the specific implementation process, the setting of the roller 206 facilitates the rotation of the protection cylinder 3. Combining with the attached Figure 6 , in order to improve the clamping stability of the protection cylinder 3, a groove adapted to the roller 206 is provided on the end face of the protection cylinder 3.

[0029] Among them, a number of balls 204 are arranged on the step surface of the step 203, and the lower end surface of the protection cylinder 3 is in contact with the balls 204 on the step 203, so that it can not only limit the protection cylinder, but also ensure that the protection cylinder can rotate along the inner cutting cylinder.

[0030] Combined with the attached Figure 6 , in the specific implementation process, in order to facilitate the extraction of the core sample from the protection cylinder 3, the protection cylinder 3 is assembled by two or three semicircular arc plates.

[0031] In some embodiments, the cutting blade 102 extends from the lower end surface of the inner cutting cylinder 2 to the outer cutting cylinder 1. That is to say, the distance between the upper end surface of the cutting blade and the lower end surface of the inner cutting cylinder is relatively small. When the cutting blade encounters a hard soil body, the lower end surface of the inner cutting cylinder can play a certain supporting role for the cutting blade, reducing the problem of the cutting blade breaking due to torsion and improving the service life of the cutting blade.

[0032] In some embodiments, when the cutting blade 102 cuts the bottom of the core sample, the length of the cutting blade 102 extending out of the outer cutting cylinder 1 is adjusted, and the bottom of the core sample is cut by means of multiple cuts. Thus, the problem of the cutting blade breaking due to excessive cutting depth is avoided.

[0033] In some embodiments, the outer cutting cylinder 1 is formed with a convex platform, a chute 103 is opened in the convex platform, the cutting blade 102 is mutually adapted to the chute 103, the outer cutting cylinder 1 is provided with a vertical groove 104 along the height direction, the vertical groove 104 is mutually communicated with the chute 103, a pulley is installed at the position where the vertical groove 104 is communicated with the chute 103, a vertical slider 106 is installed in the vertical groove 104, one end of the cutting blade 101 facing the inner bottom of the chute 103 is connected with a traction belt 105, and the other end of the traction belt 105 bypasses the pulley and is connected with the vertical slider 106. When it is necessary to extend the cutting blade 102, the vertical slider 106 is lifted upward to pull the traction belt 105, and the traction belt 105 drives the cutting blade 102 to extend out of the chute 103 during the movement and then cut the soil body.

[0034] In the specific implementation process, an anti-slip pad for increasing the friction force is arranged at the contact position between the cutting blade and the chute. On the one hand, the anti-slip pad prevents the cutting blade from sliding out of the chute, and on the other hand, it can also increase the frictional resistance when moving the vertical slider, improving the feel of adjustment.

[0035] Among them, when the outer cutting cylinder rotates, the cutting blade 102 faces the inner bottom of the chute 103 under the action of centrifugal force. Therefore, the cutting blade 102 will not automatically extend out of the chute 103 to cut the soil body. When it is necessary to retract the cutting blade (i.e., hide the cutting blade in the chute), the cutting blade 102 can be manually pressed back into the chute.

[0036] In some embodiments, a strip-shaped through hole is formed in the outer cutting cylinder 1 along the height direction, a threaded hole is formed in the vertical slider 106, and the threaded hole is provided with a locking screw and a locking nut. Thus, the vertical slider can be locked by the locking screw and the locking nut, and can be locked at different height positions of the vertical groove, so as to facilitate adjusting the length of the cutting blade extending out of the chute.

[0037] In the specific implementation process, the upper end of the vertical slider can extend out of the vertical groove and is provided with a handle, so as to facilitate adjusting the position of the vertical slider in the vertical groove by using the handle, and further adjusting the length of the cutting blade extending out of the chute.

[0038] Combined with the attached Figure 1 As an embodiment of the present invention, the inner cutting cylinder is sleeved on the inner bearing platform 7 through a bearing. A driving motor is installed on the inner bearing platform 7, and the driving motor drives the inner cutting cylinder 2 to rotate on the inner bearing platform 7. The inner bearing platform 7 is connected to the installation platform 9 through multiple second connecting rods 8, thereby providing a stable foundation for the movement of the inner cutting cylinder 2.

[0039] Among them, the outer cutting cylinder 1 is sleeved on the outer bearing platform 5 through a bearing. Since the workload of the outer bearing platform 5 for cutting and drilling is relatively large, in order to improve the stability of the outer cutting cylinder 1 during movement, the number of outer bearing platforms 5 is at least 2. Each outer bearing platform 5 is firmly fixed on the installation platform 9 through a first connecting rod 6. Among them, there should be no mechanical interference between the inner bearing platform and the outer layer platform, and the position of the first connecting rod and the inner bearing platform, so as to ensure the independence of the rotational movement of the outer cutting cylinder and the inner cutting cylinder; at the same time, the installation platform 9 can be used to drive the outer cutting cylinder 1 and the inner cutting cylinder to move downward synchronously.

[0040] In some embodiments, a connector 10 is installed on the top of the installation platform 9, and the connector 10 is used to connect with a mechanical device with a vertical lifting function, so as to drive the outer cutting cylinder and the inner cutting cylinder to move up and down by using an external mechanical device.

[0041] In the specific implementation process, a through hole for the protection cylinder 3 to pass through is provided in the middle of the installation platform 9 and the connector 10, so as to facilitate taking out and putting in the protection cylinder 3 from the inner cutting cylinder 2.

Claims

1. A sampling method for dynamic compaction foundation quality detection, characterized in that: include: (1) Driving the outer cutting cylinder to rotate, so that the outer cutting teeth on the outer cutting cylinder are used to cut and drill the outer soil; (2) After the outer cutting tube cuts and drills a certain distance, the inner cutting teeth on the inner cutting tube cut and drill the inner soil. The cutting width of the outer cutting teeth is greater than the cutting width of the inner cutting teeth, and the rotation direction of the outer cutting tube is opposite to that of the inner cutting tube. (3) During the drilling process, the inner cutting tube simultaneously drives the protective tube for covering the core sample of the compacted foundation to move downward, so that the protective tube can be sleeved on the periphery of the core sample, and there is a gap between the lower end surface of the protective tube and the lower end surface of the inner cutting tube; and during the cutting and drilling process, the inner cutting teeth of the inner cutting tube can cut the soil at the lower end of the protective tube; (4) When the lower end surface of the protective tube moves to the designed depth, a cutting blade hidden at the bottom of the outer cutting tube is extended toward the core sample of the compacted foundation. The cutting blade is located at the lower end of the inner cutting tube. The cutting blade extends to the axis of the core sample to cut the soil below the core sample. (5) Pull out the outer cutting tube, the inner cutting tube and the protective tube from the drilled hole as a whole, take out the protective tube from the inner cutting tube, and then open the protective tube to obtain the core sample of the compacted foundation.

2. The sampling method for dynamic compaction foundation quality detection according to claim 1 is characterized in that: The protective tube can rotate along with the inner cutting tube; when the friction force between the protective tube and the core sample is less than the friction force between the protective tube and the inner cutting tube, the protective tube is gradually sheathed on the periphery of the core sample by spiral sheathing; when the friction force between the protective tube and the core sample is greater than the friction force between the protective tube and the inner cutting tube, the protective tube does not rotate.

3. The sampling method for dynamic compaction foundation quality detection according to claim 1 is characterized in that: A step is arranged on the inner wall of the inner cutting cylinder, and the lower end of the protective cylinder is placed on the step; the upper end of the inner cutting cylinder is rotatably connected with a pressure rod, and a roller is installed under the pressure rod, and the upper end of the protective cylinder contacts the inner cutting cylinder through the roller.

4. The sampling method for dynamic compaction foundation quality detection according to claim 1 is characterized in that: The cutting blade extends out of the outer cutting cylinder from the lower end surface of the inner cutting cylinder.

5. The sampling method for dynamic compaction foundation quality detection according to claim 4 is characterized in that: When the cutting blade is cutting the bottom of the core sample, the length of the cutting blade extending out of the outer cutting tube is adjusted, and the bottom of the core sample is cut in a multiple-cutting manner.

6. The sampling method for dynamic compaction foundation quality detection according to claim 5 is characterized in that: The outer cutting cylinder is formed with a boss, a slide groove is opened in the boss, the cutting blade and the slide groove are adapted to each other, the outer cutting cylinder is provided with a vertical groove along the height direction, the vertical groove and the slide groove are interconnected, a pulley is installed at the position where the vertical groove and the slide groove are interconnected, a vertical slider is installed in the vertical groove, a traction belt is connected to one end of the cutting blade facing the bottom of the slide groove, and the other end of the traction belt bypasses the pulley and is connected to the vertical slider.

7. The sampling method for dynamic compaction foundation quality detection according to claim 6 is characterized in that: The outer cutting cylinder is provided with a strip-shaped through hole along the height direction, the vertical sliding block is provided with a threaded hole, and the threaded hole is equipped with a locking screw and a locking nut.

8. The sampling method for dynamic compaction foundation quality detection according to claim 1 is characterized in that: The outer cutting teeth of the outer cutting cylinder and the inner cutting teeth of the inner cutting cylinder have a partially overlapping area in the vertical projection.

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