Low-strain detection device for foundation pile of active wharf

Abstract

The utility model relates to a low-strain detection device for an active wharf foundation pile. The low-strain detection device comprises a detector body used for carrying out low-strain detection on the active wharf foundation pile and an excitation assembly aiming at the active wharf foundation pile. According to the detection device, the fastening cap bolt is obliquely and downwards embedded into the side face of the foundation pile by a certain depth, the bolt cap platform at the top of the fastening cap bolt is vertically excited through the low-strain hammer, kinetic energy of excitation is conducted to the foundation pile through the fastening cap bolt, and therefore the existing structure at the top of the foundation pile is avoided, excitation of the active wharf foundation pile is achieved, and the detection efficiency is improved. And finally, an acceleration sensor is installed on the pile side to receive signals. Compared with a pile side grooving method in foundation pile detection, only one small hole needs to be drilled in the pile side, the collected waveform effect is more accurate and effective, the construction operation difficulty is remarkably reduced, damage to the foundation pile is reduced, the working efficiency is improved, and the safety risk of operation below a wharf is reduced.

Description

Technical Field

[0001] This utility model relates to the field of pile integrity testing, specifically to a low-strain testing device for existing wharf piles. Background Technology

[0002] Pile integrity testing is a crucial part of wharf structure inspection. Since most piles are located below the mudline, their damage cannot be directly determined. Under conditions of slope deformation, ship impacts, and other natural environmental and operational loads, wharf piles are prone to fracture, tilting, and misalignment. As piles are vital load-bearing components of the wharf, their condition directly impacts its usability. Piles are underground, concealed structures, making simple and intuitive quality testing impossible. Furthermore, their quality is difficult to guarantee due to factors such as construction techniques. While various pile testing techniques exist, none are perfect, resulting in low accuracy in assessing pile integrity. The testing of existing wharf piles is particularly immature, lacking practically feasible methods. Because existing wharf piles are supported by beams (and sometimes pile caps) and panel structures, conventional low-strain reflected wave methods are insufficient for directly assessing pile integrity, leading to inconsistent test results.

[0003] Currently, the low-strain method for detecting pile integrity under free conditions at the pile top is a mature and well-established technology. However, when using the traditional low-strain method to detect the integrity of piles under existing structures, the interference factors and constraints increase, leading to slower development. The theoretical level and practical application are not yet fully mature, placing higher demands on the performance of instruments and equipment, as well as the field experience and analytical skills of technicians. For detecting piles under existing structures, a small platform can be cut along the pile side for vertical vibration, with sensors installed on another small platform or using side-mounted sensors. However, using a small platform cutting method under a wharf is difficult, time-consuming, causes significant damage to the pile, and poses high safety risks. Therefore, there is an urgent need to find a scientific and efficient method or device to detect existing wharf piles, replacing the cutting process, reducing operational difficulty while still providing reliable detection data on pile damage. Utility Model Content

[0004] To address the technical problems existing in the prior art, this utility model provides a low-strain detection device for existing wharf foundation piles.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] like Figure 1-4As shown, a low-strain testing device for existing wharf foundation piles includes a testing instrument body and a vibration excitation assembly for the existing foundation piles. The testing instrument body is connected to a side-mounted accelerometer sensor via a data cable. The vibration excitation assembly is disposed on the side surface of the existing foundation pile, and the side-mounted accelerometer sensor is tightly attached to the side surface of the existing foundation pile. The vibration excitation assembly includes a low-strain hammer, a fastening cap, and a side-mounted accelerometer sensor. The fastening cap is fixed to the side surface of the existing foundation pile at an angle downward through a drilled hole. The side-mounted accelerometer sensor is tightly attached to the side surface of the existing foundation pile using special putty.

[0007] As a preferred technical solution, the bolt cap platform at the top of the bolt is vertically vibrated by a low-strain hammer to transmit power to the existing foundation piles through the bolt. Data is collected by a side-mounted acceleration sensor to achieve low-strain detection of the existing wharf foundation piles.

[0008] As a preferred technical solution, fastening caps are inserted into the side of existing wharf foundation piles by drilling, and the kinetic energy is transferred to the foundation piles by using a vertical vibration platform for fastening the caps, so as to conduct low-strain testing on the existing wharf foundation piles.

[0009] As a preferred technical solution, low-strain testing is performed on existing wharf foundation piles by drilling, inserting fastening caps, and attaching side-mounted acceleration sensors.

[0010] As a preferred technical solution, the fastening cap is removed after the inspection is completed, and the resulting small hole is repaired with waterproof and corrosion-resistant material.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0012] This utility model discloses a low-strain testing device for existing wharf foundation piles. A fastening cap is embedded obliquely downwards to a certain depth into the side of the pile. A cap platform is installed on top of the fastening cap, and a low-strain hammer vertically vibrates the cap platform. The kinetic energy of the vibration is transmitted to the pile through the fastening cap, thus avoiding the existing structure at the top of the pile and achieving vibration of the existing wharf foundation pile. Finally, an accelerometer installed on the pile side receives the signal. Compared to the pile side grooving method recommended in relevant pile testing specifications (cutting 1-2 grooves on the pile side for vibration and sensor placement), this method only requires drilling a small hole on the pile side. It not only obtains more accurate and effective waveforms but also significantly reduces construction difficulty, minimizes damage to the pile, improves work efficiency, and reduces safety risks associated with operations below the wharf. Attached Figure Description

[0013] Figure 1 This is a three-dimensional cross-sectional structural diagram of the low strain detection device for existing wharf foundation piles according to this utility model;

[0014] Figure 2 This is a schematic diagram of the cross-sectional structure of the fastening cap bolt of the vibration component of the low strain detection device for existing wharf foundation piles according to this utility model;

[0015] Figure 3 This is a schematic diagram of the cross-sectional structure of the side-mounted sensor of the low-strain detection device for existing wharf foundation piles according to this utility model;

[0016] Figure 4 This is a schematic diagram of the cross-sectional structure of the low-strain hammer of the existing wharf foundation pile low-strain detection device of this utility model.

[0017] In the diagram: 1. Existing wharf foundation piles; 2. Baseline testing instrument body; 3. Data transmission line; 4. Low strain hammer; 5. Fastening cap bolt; 6. Side-mounted accelerometer; 7. Expansion tube; 8. Bolt; 9. Nut; 10. Bolt cap platform. Detailed Implementation

[0018] The technical solution of this utility model will be further described below with reference to specific embodiments:

[0019] like Figure 1 As shown, a low-strain testing device for existing wharf foundation piles includes a pile low-strain testing instrument body 2, which is connected to a side-mounted accelerometer sensor via a data transmission line 3. The side-mounted accelerometer sensor is tightly attached to the side surface of the existing wharf foundation pile 1 using special putty. The fastening cap 5 has a diameter of 8mm and a length of 50mm and consists of four parts: an expansion tube, a bolt, a nut, and a cap platform. When the end of the fastening cap 5 with the expansion tube is inserted into the drilled hole, the internal bolt is pulled outward when the nut is tightened, the expansion tube opens, and the pile wall, the expansion tube, and the internal bolt form a frictional self-locking mechanism, thereby firmly fixing the fastening cap 5 in the drilled hole of the pile wall and fixing the cap platform. The low-strain testing hammer 4 is vertically vibrating the cap platform and is fixed at the top of the fastening cap 5. It receives low-strain reflection data through a side-mounted acceleration sensor and transmits it to the low-strain testing instrument for the foundation pile, thereby realizing low-strain testing of the existing wharf. Compared with the pile side grooving method recommended in relevant foundation pile testing specifications (cutting 1-2 grooves on the pile side for vibration and sensor placement), this device only requires drilling a small hole with a diameter of 10mm and a depth of about 40mm on the pile side. Not only is the waveform collected more accurate and effective, but it also significantly reduces the difficulty of construction operations, reduces damage to the foundation pile, improves work efficiency, and reduces the safety risks of operations below the wharf.

[0020] The bolt cap platform at the top of the bolt is tightened by vertical excitation with a low-strain hammer, and the data is transmitted to the existing foundation piles through the tightening bolt. Data is collected by a side-mounted acceleration sensor to achieve low-strain detection of the existing wharf foundation piles.

[0021] By drilling holes and inserting fastening caps into the sides of existing wharf foundation piles, kinetic energy is transferred to the foundation piles using a vertical vibration platform for the fastening caps, thus enabling low-strain testing of the existing wharf foundation piles.

[0022] Low-strain testing was conducted on existing wharf foundation piles by drilling, inserting fastening caps, and attaching side-mounted acceleration sensors.

[0023] After the inspection is completed, the fastening cap is removed, and the resulting small drill hole is repaired with waterproof and corrosion-resistant material.

[0024] The method for using the low-strain testing device for existing wharf foundation piles includes the following steps:

[0025] Step 1: Set up excitation points for the piles that need to be tested for low strain below the existing wharf. To facilitate drilling and excitation, the excitation point should be at least 30cm away from the top of the pile and the water surface. After the excitation point is determined, use a handheld electric drill to drill a hole with a diameter of 10mm and a depth of 40mm at a 45° downward angle at the test point. After cleaning the dust, insert the fastening cap into the drill hole, tighten the nut, and fix the fastening cap firmly in the drill hole. Then tighten the cap platform on the top of the fastening cap.

[0026] Step 2: Connect one end of the side-mounted accelerometer to the low-strain pile detector, and firmly attach the other end to the side surface of the pile detection point using special putty. The angle between the excitation point and the plane projection of the detection point and the line connecting the pile center should be 90°.

[0027] Step 3: Turn on the low strain tester for the foundation pile, set the project name, and set parameters such as pile length and pile diameter to prepare for data collection;

[0028] Step 4: After completing the above preparations, click "Start Acquisition" and use a low-strain hammer to vertically excite the cap platform. Stop acquisition when at least three relatively consistent data waveforms are obtained.

[0029] This embodiment is merely a further explanation of the present invention and is not intended to limit the present invention. Those skilled in the art can make non-creative modifications to this embodiment as needed after reading this specification, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A low-strain detection device for existing wharf foundation piles, characterized in that, The device includes a detector body and a vibration excitation assembly for existing foundation piles. The detector body is connected to a side-mounted accelerometer sensor via a data cable. The vibration excitation assembly is disposed on the side surface of the existing foundation pile, and the side-mounted accelerometer sensor is tightly attached to the side surface of the existing foundation pile. The vibration excitation assembly includes a low-strain hammer, a fastening cap, and a side-mounted accelerometer sensor. The fastening cap is fixed to the side surface of the existing foundation pile at an angle downward through a drilled hole. The side-mounted accelerometer sensor is tightly attached to the side surface of the existing foundation pile using special putty.

2. The low-strain testing device for existing wharf foundation piles according to claim 1, characterized in that, The bolt cap platform at the top of the bolt is tightened by vertical vibration using a low-strain hammer, and the data is transmitted to the existing foundation piles through the tightening bolt. Data is collected by a side-mounted acceleration sensor, enabling low-strain detection of existing wharf foundation piles.

3. The low-strain testing device for existing wharf foundation piles according to claim 1, characterized in that: By drilling holes and inserting fastening caps into the sides of existing wharf foundation piles, kinetic energy is transferred to the foundation piles using a vertical vibration platform for the fastening caps, thus enabling low-strain testing of the existing wharf foundation piles.

4. The low-strain testing device for existing wharf foundation piles according to claim 1, characterized in that: Low-strain testing was conducted on existing wharf foundation piles by drilling, inserting fastening caps, and attaching side-mounted acceleration sensors.

5. The low-strain testing device for existing wharf foundation piles according to claim 1, characterized in that, The fastening cap was removed after the inspection was completed, and the resulting small drill hole was repaired with waterproof and corrosion-resistant material.

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