A device for detecting the verticality of steel casing in pile foundations and its application method

Abstract

This invention discloses a device and its method for detecting the verticality of steel casing for pile foundations. The device includes a vehicle body, a solid-state laser emitter, a laser spot position recording device, an ultrasonic displacement sensor, a cleaning device, and a support device. The vehicle body is positioned on the inner wall of the steel casing and moves downwards along the axial direction of the casing. The solid-state laser emitter and the ultrasonic displacement sensor are both located on the upper part of the vehicle body. The laser spot position recording device is fixed above the upper edge of the steel casing. The ultrasonic displacement sensor is used to monitor the lowering depth of the vehicle body in real time, and the detection direction of the ultrasonic displacement sensor is parallel to the axial direction of the steel casing. The cleaning device is located on the lower part of the vehicle body and is used to clean the inner wall of the steel casing. The support device is located on the outer side of the vehicle body and is used to maintain the stability of the vehicle body within the steel casing. The advantages of this invention are: it can achieve real-time monitoring of the casing tilt and save manpower and material resources.

Description

Technical Field

[0001] This invention relates to the technical field of bridge pile foundation construction, and in particular to a device for detecting the verticality of steel casing for pile foundations and its usage method. Background Technology

[0002] As a core foundation type in bridge construction, pile foundations are increasingly used. Before constructing bridge pile foundations, the first step is excavating the pile holes. To prevent collapse during excavation, the pile holes are typically protected before excavation begins, i.e., a retaining wall is installed. Steel casings, due to their simple manufacturing process, stable support effect on the pile holes, and excellent waterproof performance, have become the preferred material for pile hole retaining walls. However, steel casings also present some problems during use, such as insufficient positioning accuracy, difficulty in measuring deformation, and a tendency to tilt. These issues have always been significant quality risks in pile foundation construction. Excessive deviation or tilting of the pile foundation can severely impact construction progress. Therefore, developing an efficient and practical method for positioning and tilting calculation of steel casings for pile foundations is extremely urgent and important.

[0003] Traditional methods for detecting the verticality of pile casings typically employ a plumb line to measure the top of the casing, thus determining its verticality. However, this method is slow, inefficient, and unsuitable for current applications, requiring improvement. To address these issues, we propose a device and method for detecting the verticality of pile foundation steel casings. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a device and method for detecting the verticality of steel casings for pile foundations. The device includes a vehicle body, a solid-state laser emitter, a laser spot position recording device, an ultrasonic displacement sensor, a cleaning device, and a support device. The vehicle body is positioned on the inner wall of the steel casing and moves downwards along its axial direction. The solid-state laser emitter and the ultrasonic displacement sensor are both located on the upper part of the vehicle body. The laser emission direction of the solid-state laser emitter is parallel to the axial direction of the steel casing. The laser spot position recording device is fixed above the upper edge of the steel casing and is horizontally positioned. The ultrasonic displacement sensor is used to monitor the lowering depth of the vehicle body in real time, and its detection direction is parallel to the axial direction of the steel casing. The cleaning device is located at the lower part of the vehicle body and is used to clean the inner wall of the steel casing. The support device is located on the outer side of the vehicle body and is used to maintain the stability of the vehicle body within the steel casing. The method of use involves lowering the vehicle body after the steel casing is lowered, and a computer terminal monitors the horizontal offset of the laser spot and the lowering depth, outputting the verticality of the casing in real time. This device and its usage method can achieve the effect of real-time monitoring of the inclination of the casing and saving manpower and resources.

[0005] The objective of this invention is achieved through the following technical solutions: A device for detecting the verticality of a steel casing for pile foundations includes a vehicle body, a solid-state laser emitter, a laser spot position recording device, an ultrasonic displacement sensor, a cleaning device, and a support device. The vehicle body is mounted on the inner wall of the steel casing and moves downward along the axial direction of the steel casing. The solid-state laser emitter and the ultrasonic displacement sensor are both located on the upper part of the vehicle body. The laser emission direction of the solid-state laser emitter is parallel to the axial direction of the steel casing. The laser spot position recording device is fixed above the upper edge of the steel casing, and the photosensitive surface of the laser spot position recording device is horizontally arranged. The ultrasonic displacement sensor is used to monitor the lowering depth of the vehicle body in real time, and the detection direction of the ultrasonic displacement sensor is parallel to the axial direction of the steel casing. The cleaning device is located on the lower part of the vehicle body and is used to clean the inner wall of the steel casing. The support device is located on the outer side of the vehicle body and is used to maintain the running stability of the vehicle body within the steel casing.

[0006] The vehicle body is connected to a fixed pulley via a rope. The fixed pulley is fixed above the upper edge of the steel casing and is horizontally positioned. One end of the rope is fixedly connected to the vehicle body, and the other end passes around the fixed pulley and is connected to a winch. The winch drives the vehicle body to move downward along the axial direction of the steel casing by winding and unwinding the rope.

[0007] Guide wheels are installed on the inner side of the vehicle body.

[0008] The laser spot position recording device is a position-sensitive detector.

[0009] The cleaning device consists of a brush and a water sprayer. The brush is connected to the output shaft of a motor via a coupling. The water sprayer is located above the brush and is connected to a high-pressure water pump on the ground via a hose.

[0010] The support device includes four inclined telescopic rods and four pulleys respectively disposed at the ends of the four telescopic rods; the four telescopic rods extend obliquely from the upper front, lower front, upper rear, and lower rear of the vehicle body, and the four telescopic rods are arranged symmetrically in space; the telescopic ends of the telescopic rods are connected to the vehicle body through ball joints, and the fixed ends are connected to the pulleys through bearings; the wheel surface of the pulleys contacts the inner wall of the steel casing, and the pulleys are made to fit tightly against the inner wall of the steel casing by adjusting the length of the telescopic rods.

[0011] The laser spot position recording device and the ultrasonic displacement sensor are electrically connected to the computer terminal.

[0012] A method for using a device for detecting the verticality of steel casing in pile foundations, the method comprising the following steps: S1: Fix the laser spot position recording device and the fixed pulley above the upper edge of the steel casing respectively; fix one end of the rope to the vehicle body and the other end around the fixed pulley and connect it to the winch; start the winch and drive the vehicle body to move downward along the axis of the steel casing, and lower the vehicle body into the steel casing. S2: Real-time monitoring and recording via computer terminal of the horizontal offset of the laser spot position recording device and the lowering depth of the vehicle body collected by the ultrasonic displacement sensor: S3: The computer terminal calculates and outputs the verticality of the steel casing in real time based on the real-time collected horizontal offset of the light spot and the lowering depth; S4: When the vehicle body is lowered to the preset detection depth, data acquisition is stopped, and the solid-state laser emitter, the cleaning device, and the ultrasonic displacement sensor are turned off; the winch is controlled to retrieve the rope and lift the vehicle body to the ground; the detection data stored in the computer terminal is exported and a detection report is generated.

[0013] In step S3, the verticality of the steel casing is calculated according to the following formula. c : c =arctan( ); Where, Δ X Δ Y The horizontal offset of the light spot comprises the components in two orthogonal directions within the horizontal plane. H The depth of the drop is [the specified depth]. c The verticality of the steel casing.

[0014] The advantages of this invention are: using the vertical position of the position-sensitive detector as a reference point, the ultrasonic displacement sensor can monitor the lowering depth of the vehicle body in real time, and the ratio of the horizontal offset of the light spot to the lowering depth is the tangent of the steel casing offset angle; it is easy to operate, more efficient, and the output results are more intuitive, and it can measure the verticality of the steel casing at a deeper position. Attached Figure Description

[0015] Figure 1 This is a diagram showing the overall structural layout of the device for detecting the verticality of steel casing for pile foundations according to the present invention. Figure 2 This is a front view of the device for detecting the verticality of the steel casing of the pile foundation according to the present invention during operation; Figure 3 This is a side view of the device for detecting the verticality of the steel casing of the pile foundation according to the present invention during operation; Figure 4 This is a top view of the device for detecting the verticality of the steel casing of the pile foundation according to the present invention during operation; like Figure 1~4As shown in the figure, the labels represent: 1. Solid-state laser emitter; 2. Ultrasonic displacement sensor; 3. Cleaning device; 4. Vehicle body; 5. Telescopic pole; 6. Pulley; 7. Laser spot position recording device; 8. Fixed pulley; 9. Rope; 10. Steel casing. Detailed Implementation

[0016] The features and other related features of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, so as to facilitate understanding by those skilled in the art: Example: Figure 1~4 As shown, this embodiment relates to a device for detecting the verticality of a steel casing for pile foundations. The device mainly includes a vehicle body 4, a solid-state laser emitter 1, a laser spot position recording device 7, an ultrasonic displacement sensor 2, a cleaning device 3, and a support device. The vehicle body 4 is mounted on the inner wall of the steel casing 10 and moves downwards along the axial direction of the steel casing 10. The top surface of the steel casing 10 is higher than or level with the ground. The vehicle body 4 is made of lightweight alloy material (300mm long × 200mm wide × 150mm high) and has an overall rectangular structure. Guide wheels (50mm in diameter) are installed on the inner side of the vehicle body 4 to facilitate its movement. The vehicle body 4 is connected to the fixed pulley 8 (100mm in diameter) via a rope 9 (high-strength nylon rope, 5mm in diameter). The fixed pulley 8 is fixed above the upper edge of the steel casing 10 by a bracket and is set horizontally. One end of the rope 9 is fixedly connected to the lifting ring of the vehicle body 4, and the other end passes around the fixed pulley 8 and is connected to the winch. The winch drives the vehicle body 4 to move downward along the axis of the steel casing 10 by winding and unwinding the rope 9 (winding and unwinding speed is 0.5-1m / min).

[0017] Both the solid-state laser emitter 1 and the ultrasonic displacement sensor 2 are located on the upper part of the vehicle body 4. The laser emission direction of the solid-state laser emitter 1 is parallel to the axis of the steel casing 10. The laser spot position recording device 7 is fixed above the upper edge of the steel casing 10 by an adjustable bracket, and the photosensitive surface of the laser spot position recording device 7 is horizontally set. The laser spot position recording device 7 is a position sensitive detector (PSD). The adjustable bracket is installed on the upper edge of the steel casing 10 to ensure that the photosensitive surface of the laser spot position recording device 7 remains horizontal. The ultrasonic displacement sensor 2 is used to monitor the lowering depth of the vehicle body 4 in real time, and the detection direction of the ultrasonic displacement sensor 2 is parallel to the axis of the steel casing 10. The laser spot position recording device 7 and the ultrasonic displacement sensor 2 are electrically connected to a computer terminal. Specifically, the solid-state laser emitter 1 is a semiconductor solid-state laser with a wavelength of 650nm (power 5mW, beam diameter 2mm), which is fixed in the mounting slot on the upper part of the vehicle body 4 by bolts. During installation, it is calibrated with a level to ensure that the laser emission direction is parallel to the inner wall of the steel casing 10 (error ≤0.5°). The laser beam is horizontally projected onto the laser spot position recording device 7. The ultrasonic displacement sensor 2 (measurement range 0-50m, accuracy ±0.1%) is fixed next to the solid-state laser emitter 1. Its detection direction is parallel to the axis of the steel casing 10. It is rigidly connected to the upper part of the vehicle body 4 through a bracket. The signal output line of the ultrasonic displacement sensor 2 is routed along the side of the vehicle body 4 and connected to a computer terminal on the ground for real-time monitoring of the lowering depth of the vehicle body 4 (the lowering depth is the distance measured along the axis of the steel casing 10, which is approximated as the vertical depth when tilted at a small angle). The ultrasonic displacement sensor 2 measures the distance between the sensor and the reference surface below by emitting ultrasonic pulses and receiving reflected echoes, thereby obtaining the lowering depth of the vehicle body 4 in real time. The initial position of the laser spot of the laser spot recording device 7 (effective photosensitive area 50mm×50mm, resolution 0.01mm) is located at the center of the photosensitive surface; the signal cable of the laser spot recording device 7 is connected to a computer terminal, and the terminal is equipped with dedicated data processing software, which can record the horizontal offset of the laser spot (X, Y axis coordinates) in real time.

[0018] The cleaning device 3 is located at the lower part of the vehicle body 4 and is used to clean the inner wall of the steel casing 10. The cleaning device 3 consists of a brush (150mm diameter nylon brush) and a water sprayer (mini high-pressure water sprayer, flow rate 0.5L / min, working pressure 0.3MPa). The brush is connected to the output shaft of the motor (100W power, 300rpm speed) via a coupling, and the brush contacts the inner wall of the steel casing 10 (contact pressure 5-10N). The water sprayer is located above the brush and is connected to a high-pressure water pump on the ground via a hose to rinse away stubborn mud from the inner wall of the steel casing 10. The motor control wire is routed along the vehicle body 4 and connected to the ground control switch.

[0019] A support device is located on the outside of the vehicle body 4 and is used to maintain the stability of the vehicle body 4 within the steel casing 10. The support device includes four inclined telescopic rods 5 (20mm in diameter, telescopic range 100-300mm) and four pulleys 6 (30mm in diameter) respectively located at the ends of the four telescopic rods 5. The four telescopic rods 5 extend obliquely from the upper front, lower front, upper rear, and lower rear of the vehicle body 4, and are arranged symmetrically in space. Each telescopic rod 5 forms a 60° angle with the downward direction of the vehicle body 4 (i.e., the axial direction of the steel casing 10), and its lateral component forms a 45° angle with the longitudinal direction of the vehicle body 4. The telescopic ends of the telescopic rods 5 are connected to the vehicle body 4 via ball joints, and the fixed ends are connected to the pulleys 6 via bearings. The wheel surface of the pulleys 6 contacts the inner wall of the steel casing 10. By adjusting the length of the telescopic rods 5, the pulleys 6 are made to fit tightly against the inner wall of the steel casing 10 (preload 10-15N).

[0020] like Figure 1~4 As shown, this embodiment also relates to a method of using a device for detecting the verticality of steel casing in pile foundations. The method mainly includes the following steps: S1: Fix the laser spot position recording device 7 and the fixed pulley 8 above the upper edge of the steel casing 10 respectively; fix one end of the rope 9 to the vehicle body 4, and connect the other end to the winch after passing over the fixed pulley 8; start the winch, and drive the vehicle body 4 to move downward along the axis of the steel casing 10 through the winch, and lower the vehicle body 4 into the inside of the steel casing 10.

[0021] In this embodiment, before testing, the status of each component of the device is checked: the solid-state laser emitter 1 is confirmed to be working normally (the beam is stable and the direction is correct), the laser spot position recording device 7 communicates normally with the computer terminal (the spot position can be displayed in real time), the ultrasonic displacement sensor 2 is calibrated (zero position error ≤ 0.1mm), the brush and water sprayer of the cleaning device 3 are working normally, the telescopic rod 5 of the support device extends and retracts flexibly, and the pulley 6 rotates smoothly.

[0022] After the steel casing 10 is lowered into place, the fixed pulley 8 and the laser spot position recording device 7 are installed. The photosensitive surface of the laser spot position recording device 7 is ensured to be horizontal, and the initial coordinates of the center of the photosensitive surface of the laser spot position recording device 7 are recorded. X 0, Y 0).

[0023] S2: The horizontal offset of the laser spot collected by the laser spot position recording device 7 and the lowering depth of the vehicle body 4 collected by the ultrasonic displacement sensor 2 are monitored and recorded in real time through the computer terminal.

[0024] In this embodiment, the cleaning device 3 is activated: the motor drives the brush to rotate, and the high-pressure water pump is activated to make the water sprayer work, so as to clean the mud and debris on the inner wall of the steel casing 10 in advance, and ensure that the vehicle body 4 descends smoothly.

[0025] Start the winch and slowly lower the vehicle body 4 at a speed of 0.5 m / min. At the same time, activate the data recording functions of the solid-state laser emitter 1, the ultrasonic displacement sensor 2, and the computer terminal. The laser spot position recording device 7 records the coordinates of the laser spot in real time. X t , Y t The computer terminal calculates the horizontal offset Δ of the laser spot. X = X t - X 0, Δ Y = Y t -Y0; The ultrasonic displacement sensor 2 monitors the lowering depth of the vehicle body 4 in real time. H And transmit the data to the computer terminal; The computer terminal synchronizes and stores the offset (Δ) at a frequency of 1 second per cycle. X Δ Y ) and depth of deployment H .

[0026] S3: The computer terminal calculates and outputs the verticality of the steel casing 10 in real time based on the real-time collected horizontal offset of the light spot and the lowering depth.

[0027] In this embodiment, the verticality of the steel casing 10 is calculated using the following formula. c : c =arctan( ); Where, Δ X Δ Y These are the components of the horizontal offset of the light spot in two orthogonal directions within the horizontal plane. H To reduce the depth, c The verticality of the steel casing (comprehensive offset angle).

[0028] Specifically, the dedicated software on the computer terminal calculates the offset angle of the steel casing 10 at different depths based on the real-time collected data: On the horizontal surface X directional offset angle α =arctan(Δ X / H ); On the horizontal surface Y directional offset angle β =arctan(Δ Y / H ); Overall offset angle c =arctan( ).

[0029] The software displays the angle curve in real time. α - H curve, β - H curve, c - H (curve), and perpendicularity requirements as specified in the pre-defined specifications (such as...) c The system compares the values ​​of ≤1% with the target depth. When γ > 1% is detected, an audible and visual alarm is automatically triggered, indicating that the verticality of the steel casing at that depth exceeds the standard.

[0030] S4: When the vehicle body 4 is lowered to the preset detection depth (such as 90% of the total depth of the steel casing 10), stop data acquisition, turn off the solid-state laser emitter 1, the cleaning device 3 and the ultrasonic displacement sensor 2; control the winch to retrieve the rope 9 and lift the vehicle body 4 to the ground; export the detection data stored in the computer terminal and generate a detection report.

[0031] In this embodiment, the winch is controlled to retrieve the rope 9 and slowly lift the vehicle body 4 to the ground. During the process, the support device is kept working normally to avoid the vehicle body from colliding with the inner wall of the steel casing 10.

[0032] Export the test data stored on the computer terminal and generate a test report, which includes: the depth-offset angle curve of the steel casing, the location and value of the deviation, the verticality qualified range, etc., to provide a basis for subsequent construction adjustments.

[0033] In addition, to ensure detection accuracy and stability, this embodiment also provides methods for adjusting key parameters of the device: Calibration of solid-state laser emitter 1: Build a calibration platform outside the steel casing 10, fix the solid-state laser emitter 1 on the adjustable bracket, adjust the emission direction with a precision angle gauge to ensure that the laser beam is parallel to the platform baseline (deviation ≤0.01°), and lock the emitter position after calibration.

[0034] Adjusting the horizontality of the photosensitive surface of the laser spot position recording device 7: Use an electronic level (accuracy 0.01°) to place on the photosensitive surface of the laser spot position recording device 7. Adjust the height of the bracket to make the level display horizontal (bubble centered) and ensure that the angle between the photosensitive surface and the horizontal plane is ≤0.05°.

[0035] Preload adjustment of support device: The length is changed by adjusting the nut of telescopic rod 5, and the contact force between pulley 6 and the inner wall of steel casing 10 is measured by using a tension gauge to keep the preload of the four pulleys 6 consistent (12±2N), which ensures the stable operation of the vehicle body 4 and avoids excessive friction affecting the lowering accuracy.

[0036] Ultrasonic displacement sensor 2 calibration: Place the vehicle body 4 on a platform with a known height (e.g., 1m, 2m, 5m), record the sensor's measured value, compare it with the actual height, calculate the correction coefficient, and eliminate system error through software compensation (error ≤ 0.5mm after calibration).

[0037] The advantages of this invention are: using the vertical position of the position-sensitive detector as a reference point, the ultrasonic displacement sensor can monitor the lowering depth of the vehicle body in real time, and the ratio of the horizontal offset of the light spot to the lowering depth is the tangent of the steel casing offset angle; it is easy to operate, more efficient, and the output results are more intuitive, and it can measure the verticality of the steel casing at a deeper position.

Claims

1. A device for detecting the verticality of steel casing for pile foundations, characterized in that... The device includes a vehicle body, a solid-state laser emitter, a laser spot position recording device, an ultrasonic displacement sensor, a cleaning device, and a support device. The vehicle body is mounted on the inner wall of a steel casing and moves downward along the axial direction of the steel casing. The solid-state laser emitter and the ultrasonic displacement sensor are both located on the upper part of the vehicle body. The laser emission direction of the solid-state laser emitter is parallel to the axial direction of the steel casing. The laser spot position recording device is fixed above the upper edge of the steel casing, and the photosensitive surface of the laser spot position recording device is horizontally set. The ultrasonic displacement sensor is used to monitor the lowering depth of the vehicle body in real time, and the detection direction of the ultrasonic displacement sensor is parallel to the axial direction of the steel casing. The cleaning device is located on the lower part of the vehicle body and is used to clean the inner wall of the steel casing. The support device is located on the outer side of the vehicle body and is used to maintain the running stability of the vehicle body within the steel casing.

2. The device for detecting the verticality of steel casing for pile foundations as described in claim 1, characterized in that... The vehicle body is connected to a fixed pulley via a rope. The fixed pulley is fixed above the upper edge of the steel casing and is horizontally positioned. One end of the rope is fixedly connected to the vehicle body, and the other end passes around the fixed pulley and is connected to a winch. The winch drives the vehicle body to move downward along the axial direction of the steel casing by winding and unwinding the rope.

3. The device for detecting the verticality of steel casing for pile foundations as described in claim 1, characterized in that... Guide wheels are installed on the inner side of the vehicle body.

4. The device for detecting the verticality of steel casing for pile foundations as described in claim 1, characterized in that... The laser spot position recording device is a position-sensitive detector.

5. The device for detecting the verticality of steel casing for pile foundations as described in claim 1, characterized in that... The cleaning device consists of a brush and a water sprayer. The brush is connected to the output shaft of a motor via a coupling. The water sprayer is located above the brush and is connected to a high-pressure water pump on the ground via a hose.

6. The device for detecting the verticality of steel casing for pile foundations as described in claim 1, characterized in that... The support device includes four inclined telescopic rods and four pulleys respectively disposed at the ends of the four telescopic rods; the four telescopic rods extend obliquely from the upper front, lower front, upper rear, and lower rear of the vehicle body, and the four telescopic rods are arranged symmetrically in space; the telescopic ends of the telescopic rods are connected to the vehicle body through ball joints, and the fixed ends are connected to the pulleys through bearings; the wheel surface of the pulleys contacts the inner wall of the steel casing, and the pulleys are made to fit tightly against the inner wall of the steel casing by adjusting the length of the telescopic rods.

7. The device for detecting the verticality of steel casing for pile foundations as described in claim 1, characterized in that... The laser spot position recording device and the ultrasonic displacement sensor are electrically connected to the computer terminal.

8. The method of using the device for detecting the verticality of steel casing for pile foundations as described in any one of claims 1 to 7, characterized in that... The method of use includes the following steps: S1: Fix the laser spot position recording device and the fixed pulley above the upper edge of the steel casing respectively; fix one end of the rope to the vehicle body and the other end around the fixed pulley and connect it to the winch; start the winch and drive the vehicle body to move downward along the axis of the steel casing, and lower the vehicle body into the steel casing. S2: Real-time monitoring and recording via computer terminal of the horizontal offset of the laser spot position recording device and the lowering depth of the vehicle body collected by the ultrasonic displacement sensor: S3: The computer terminal calculates and outputs the verticality of the steel casing in real time based on the real-time collected horizontal offset of the light spot and the lowering depth; S4: When the vehicle body is lowered to the preset detection depth, data acquisition is stopped, and the solid-state laser emitter, the cleaning device, and the ultrasonic displacement sensor are turned off; the winch is controlled to retrieve the rope and lift the vehicle body to the ground; the detection data stored in the computer terminal is exported and a detection report is generated.

9. The method of using the device for detecting the verticality of a steel casing for pile foundations as described in claim 8, characterized in that... In step S3, the verticality of the steel casing is calculated according to the following formula. γ : γ =arctan( ); Where, Δ X Δ Y The horizontal offset of the light spot comprises the components in two orthogonal directions within the horizontal plane. H The depth of the drop is [the specified depth]. γ The verticality of the steel casing.

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