Cone dynamic penetration test device

Abstract

According to the cone dynamic penetration test device, through arrangement of the motor lifting assembly, lifting of the center penetrating hammer can be achieved in an electric mode, and when the center penetrating hammer ascends and impacts the upper limiting switch, the controller can stop supplying power to the motor and even enables the motor to rotate reversely so that the center penetrating hammer can fall freely. And through the arrangement of the limit switch and the controller, the hammering test can be automatically carried out, and the falling distance of each hammering of the piercing hammer can be limited to conform to the specification. The cone dynamic penetration test device disclosed by the utility model is relatively high in automation degree, and can greatly reduce the manual requirement and greatly reduce the error of manual operation.

Description

Technical Field

[0001] This utility model relates to the field of engineering testing, and in particular to a cone dynamic penetration test device for determining the physical properties of soil layers. Background Technology

[0002] The dynamic cone penetration test (DPT) uses a drop hammer of a certain mass to drive a standard-sized cone probe into the soil layer from a certain free fall height. The physical properties of the soil layer are determined based on the ease with which the probe penetrates. The DPT is one of the in-situ testing methods used in highway bridge and culvert engineering surveys. Currently, this method typically involves several people working together to lift the drop hammer (core hammer) to a certain height and then simultaneously releasing it, allowing it to fall freely and strike the hammer pad, thus driving the probe into the soil layer. According to specifications, the penetration process should be as continuous as possible. For example, in a heavy-duty DPT test, the hammer mass is 63.5 kg, the required drop height is 76 cm, and the hammering rate should be 15-30 blows per minute. Manually lifting the hammer for this test results in relatively large deviations in drop height control and is extremely labor-intensive. Summary of the Invention

[0003] Based on the aforementioned technical problems existing in the prior art, this utility model proposes a cone dynamic penetration test device.

[0004] The conical dynamic penetration test device of this utility model includes a probe, a penetration rod, a hammer pad, a guide rod, and a penetrating hammer. The probe, the penetration rod, the hammer pad, and the guide rod are arranged in order from bottom to top. The penetrating hammer has a penetrating hole. The size of the hammer pad is larger than the size of the penetrating hole. The guide rod can pass through the penetrating hammer through the penetrating hole and guide the penetrating hammer to slide freely along the guide rod. The penetrating hammer is provided with a handle.

[0005] Its core feature is that the device also includes:

[0006] The lifting assembly, used to lift and release the mandrel, includes a motor, a timing pulley, and a traction rope. The motor is connected to the timing pulley via a motor shaft, and one end of the traction rope is wound and fixed to the timing pulley, while the other end is connected to a handle.

[0007] A limiting assembly for limiting the vertical drop distance of the hammer, including a limit switch disposed on one side of the guide rod; and

[0008] The controller can be connected to the upper limit switch via electrical, magnetic, or electromagnetic signals to collect the switching signals of the upper limit switch. The controller can also be connected to the motor via electrical, magnetic, or electromagnetic signals to control the operation of the motor.

[0009] In addition, a displacement sensor can be set up to sense the displacement of the probe as it penetrates the soil layer, thereby determining the test endpoint.

[0010] This invention relates to a dynamic cone penetration test device. Through the arrangement of the motor lifting assembly, the cone penetration hammer can be electrically lifted. When the hammer rises and strikes the upper limit switch, the controller can stop the power supply to the motor or even reverse the motor to allow the hammer to fall freely. The limit switch and controller not only enable automatic operation of the hammer test but also ensure that the drop distance of each hammer strike meets the specified requirements. This dynamic cone penetration test device has a high degree of automation, significantly reducing the need for manual labor and minimizing errors caused by manual operation. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the cone dynamic penetration test device of this utility model.

[0012] Figure 2 A schematic diagram of the conical dynamic cone penetration test device of this utility model using a dual-shaft extension motor. Detailed Implementation

[0013] The present invention will be further described in detail below with reference to embodiments:

[0014] See Figure 1 The conical dynamic penetrometer provided by this utility model is a further improvement on the existing device. The existing device includes, as shown in the figure, a probe 11, a penetrometer rod 12, a hammer pad 13, a guide rod 14, and a penetrating hammer 21. The probe 11, penetrometer rod 12, hammer pad 13, and guide rod 14 are arranged sequentially from bottom to top. The penetrating hammer 21 has a penetrating hole 22. The hammer pad 13 is larger than the size of the penetrating hole 22. The guide rod 14 can pass through the penetrating hammer 21 through the penetrating hole 22 and guide the penetrating hammer 21 to slide freely along the guide rod 14. Two handles 23 are symmetrically provided on the upper axis of the penetrating hammer 21. Of course, the handles 21 can extend from the side wall of the penetrating hammer 21 as shown in the figure, or they can be set on any suitable surface of the penetrating hammer 21, such as its upper surface. Furthermore, the probe 11, penetrometer rod 12, and hammer pad 13 can be joined together or are an integral structure. There are no special requirements in this utility model. Furthermore, the guide rod 14 and the hammer pad 13 can also be an integral structure. However, for the convenience of installing and disassembling the through hammer 21 and transporting the equipment as a whole, it is preferable that the guide rod 14 is usually detachably connected to the hammer pad 13, for example, by threaded coupling.

[0015] An improvement of this utility model is that the cone dynamic penetration test device further includes a lifting component, a support component, a limiting component, and a controller 60. Among these,

[0016] The lifting assembly, used for lifting and releasing the core hammer 21, includes a motor 41, a synchronous pulley 43, and a traction rope 44. The motor 41 is connected to the synchronous pulley 43 via a motor shaft. One end of the traction rope 44 is wound and fixed to the synchronous pulley 43, and the other end is connected to a handle 23. As shown in the figure, the rotation of the motor 41 can lift the core hammer 21 to a designated position. Of course, if the motor 41 is de-energized or reversed after being lifted to the appropriate position, the core hammer 21 will naturally fall and strike the hammer pad 13, thereby pushing the probe 11 into the soil layer. The motor 41 can be as follows: Figure 1 Common single-shaft extension motors can also be like... Figure 2 A dual-shaft extension motor is used to improve traction stability.

[0017] A support assembly for supporting the lifting assembly includes at least three support rods 31 and a lateral support 32. The lateral support 32 is supported by the at least three support rods 31 and has a through hole 322 through which the traction rope 44 passes. It is understood that the support assembly primarily supports the motor 41, for example, by fixing it to the lateral support 32 via a motor mount 42. Since the synchronous pulley 43 and the traction rope 44 are essentially connected to the motor, they are also supported by the support assembly. The through hole 322 provides a channel for the traction rope 44 to extend to the lower end of the lateral support 32 for secure connection to the handle 23 of the center hammer 21.

[0018] A limiting component, used to limit the vertical drop distance of the hammer 21, includes a limit switch 18 arranged on one side of the guide rod 14. The vertical drop distance is the distance from the upper surface of the hammer 21 to the limit switch 18 when the hammer 21 is in contact with the hammer pad 13. It varies depending on the test type. For example, the drop distance is 50 cm for a light cone penetration test, 76 cm for a medium cone penetration test, and 100 cm for a heavy cone penetration test.

[0019] A controller 60 is connected to a limit switch 18 via electrical, magnetic, or electromagnetic signals to collect the switching signals of the limit switch 18. The controller 60 is also connected to a motor 41 via electrical, magnetic, or electromagnetic signals to control the operation of the motor 41. When the hammer 21 is raised to the point where it touches the limit switch 18, the controller 60 can be operated to de-energize the motor 41, allowing the hammer 21 to fall under its own weight and strike the hammer pad 13. A further preferred embodiment is that when the hammer 21 is raised to the point where it touches the limit switch 18, the controller 60 can be operated to drive the motor 41 in high-speed reverse rotation to quickly release the traction rope 44, reducing the resistance of the motor 41 during the fall of the hammer 21 under its own weight.

[0020] In another embodiment, the cone penetration test apparatus further includes a hammer switch 16 disposed on one side of the hammer pad 13. The controller 60 is connected to the hammer switch 16 via electrical, magnetic, or electromagnetic signals to collect the switching signal of the hammer switch 16. When the penetrating hammer 21 strikes the hammer pad 13, it will touch the hammer switch 16. The signal triggering the hammer switch 16 can provide the controller 60 with a signal to raise the penetrating hammer 21 again, or the controller 60 can record the number of hammer blows to reach the desired penetration depth, or both.

[0021] In another embodiment, the hammer switch 16 is fixed to one side of the hammer pad 13 by a first elastic rod 15; the limit switch 18 is fixed to one side of the guide rod 14 by a second elastic rod 17. The elastic connecting parts can provide a buffer for the switch, preventing damage to the switch caused by the hammer hitting the switch hard.

[0022] In another embodiment, the cone penetration test apparatus is characterized by further including a displacement sensor 50 arranged on the transverse support 32, used to detect the vertical distance of the displacement sensor 50 relative to the upper surface of the hammer 21. The controller 60 can be electrically, magnetically, or electromagnetically connected to the displacement sensor 50 to collect the signal of the displacement sensor 50. The displacement sensor 50 can collect the change in its vertical distance relative to the upper surface of the hammer 21, that is, collect the vertical distance of the displacement sensor 50 relative to the upper surface of the hammer 21 after each hammering, and compare it with the initial vertical distance of the displacement sensor 50 relative to the upper surface of the hammer 21 when no hammering has occurred and the hammer 21 is in contact with the hammer pad 13. In this way, the penetration depth of the probe 11 can be detected. When the signal collected by the controller 60 indicates that the penetration depth has reached the target value, the test can be automatically stopped. The displacement sensor 50 can continuously detect the vertical distance between itself and the upper surface of the hammer 21, that is, it can also detect the distance during the lifting and lowering of the hammer. The point where the distance is maximized can be used as the data comparison value of the penetration depth. Alternatively, when the hammer switch 16 is triggered, the controller 60 can start the displacement sensor 50 to immediately detect the distance, that is, the distance is collected before the hammer 21 is lifted again and directly used as the data comparison value of the penetration depth.

[0023] In another embodiment, a leveling bolt 311 is provided at the upper end of the support rod 31 for adjusting and keeping the transverse support 32 horizontal. Furthermore, the transverse support 32 is provided with a retaining hole 321 through which the guide rod 14 passes. That is, during the penetration test, the retaining hole 321 ensures that the probe 11, probe rod 12, hammer pad 13, and guide rod 14 remain essentially vertical without requiring manual support.

[0024] In another embodiment, the traction rope 44 is connected to the handle 23 via a quick connector 45, thereby facilitating the quick assembly and disassembly of the equipment.

[0025] In another preferred embodiment, the motor 41 is a bidirectional variable frequency motor. The controller 60 can control the motor 41 to lift at a relatively low speed during the lifting process, especially when the hammer 21 is about to approach the limit switch 18, to protect the limit switch 18. After the hammer 21 triggers the limit switch 18, the motor 41 can immediately rotate in the opposite direction at a relatively high speed to release the traction rope 44, thus ensuring the free fall motion of the hammer 21 as much as possible.

[0026] After assembly, the operation of the cone dynamic penetration test device of this utility model includes the following steps:

[0027] 1) The hammer 21 is placed on the hammer pad 13, and the displacement sensor 50 senses the initial vertical distance of the displacement sensor 50 relative to the upper surface of the hammer 21 (if there is no displacement sensor 50, it can be measured manually, the same below).

[0028] 2) Controller 60 starts motor 41 to lift the through hammer 21;

[0029] 3) When the hammer 21 comes into contact with the trigger limit switch, the controller 60 cuts off the power to the motor 41 or drives the motor 41 to rotate in the opposite direction, releasing the hammer 21 to perform free fall motion.

[0030] 4) The hammer 21 strikes the hammer pad 13, and the hammer 21 simultaneously abuts against and triggers the hammer switch 16. The displacement sensor 50 senses the distance between the displacement sensor 50 and the upper surface of the hammer 21. The controller 60 controls the motor 41 to lift the hammer 21 again based on the signal from the hammer switch 16, and increments the hammer count by 1. (In the absence of the hammer switch 16, the controller 60 can be manually operated again to lift the hammer 21 and count manually.)

[0031] Repeat steps 2)-4) until the soil penetration depth reaches the target value.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A conical dynamic sounding device, comprising a probe (11), a sounding rod (12), a hammer pad (13), a guide rod (14) and a driving hammer (21), the probe (11), the sounding rod (12), the hammer pad (13) and the guide rod (14) are arranged in sequence from bottom to top, the driving hammer (21) has a through hole (22), the hammer pad (13) is larger than the size of the through hole (22), the guide rod (14) can pass through the driving hammer (21) from the through hole (22) and guide the driving hammer (21) to slide freely along the guide rod (14), and two handles (23) are arranged on the driving hammer (21) in axial symmetry. characterized in that Further comprising: I.a lifting assembly for lifting and releasing the driving hammer (21), comprising a motor (41), two synchronous wheels (43) and two traction ropes (44), the motor (41) is connected with the two synchronous wheels (43) through a motor shaft, and the two traction ropes (44) are respectively wound around the two synchronous wheels (43) at one end and connected with the two handles (23) at the other end; II.a support assembly for bearing the lifting assembly, comprising at least three support rods (31) and a transverse support (32), the transverse support (32) is supported by the at least three support rods (31), and the transverse support (32) is provided with a through hole (322) through which the traction rope (44) passes; III.a limiting assembly for limiting the vertical falling distance of the driving hammer (21), comprising a limiting switch (18) arranged on one side of the guide rod (14); IV.a controller (60), the controller (60) is electrically, magnetically or electromagnetically connected with the limiting switch (18) to collect the switch signal of the limiting switch (18), and the controller (60) is electrically, magnetically or electromagnetically connected with the motor (41) to control the operation of the motor (41).

2. The cone penetration test apparatus of claim 1, wherein: Further comprising a hammering switch (16) arranged on one side of the hammer pad (13), and the controller (60) is electrically, magnetically or electromagnetically connected with the hammering switch (16) to collect the switch signal of the hammering switch (16).

3. The cone penetration test apparatus of claim 2, wherein: The hammering switch (16) is fixed on one side of the hammer pad (13) through a first elastic rod (15), and the limiting switch (18) is fixed on one side of the guide rod (14) through a second elastic rod (17).

4. The cone penetration test apparatus of claim 1, wherein: Further comprising a displacement sensor (50) arranged on the transverse support (32), for detecting the vertical distance between the displacement sensor (50) and the upper end surface of the driving hammer (21), and the controller (60) can be electrically, magnetically or electromagnetically connected with the displacement sensor (50) to collect the signal of the displacement sensor (50).

5. The cone penetration test apparatus of claim 1, wherein: The upper end of the support rod (31) is provided with a leveling bolt (311) for adjusting the transverse support (32) to be horizontal.

6. The cone penetration test apparatus of claim 5, wherein: The motor (41) is fixed on the transverse support (32) through a motor base (42).

7. The cone penetration test apparatus of claim 5, wherein: The transverse support (32) is provided with a retaining hole (321) through which the guide rod (14) passes.

8. The cone penetration test apparatus of claim 1, wherein: The traction rope (44) is connected with the handle (23) through a quick connector (45).

9. The cone penetration test apparatus of any one of claims 1-8, wherein: The motor (41) is a bidirectional variable frequency motor.

10. The cone penetration test apparatus of claim 9, wherein: The motor (41) is a double-shaft extension motor, and the two synchronous wheels (43) are respectively arranged at the two ends of the shaft of the double-shaft extension motor.

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