A three-dimensional imaging device for pile foundation hole wall, use method, and imaging method

Abstract

The present invention provides a three-dimensional imaging device for a pile foundation hole wall, a method for using the device, and an imaging method. The three-dimensional imaging device for a pile foundation hole wall includes a reaction frame, a lifting actuator, a casing, a torsion actuator, an imaging probe, an active cable, a fixed cable, and a control terminal. The reaction frame fixes the lifting actuator, the lifting actuator is connected to the control terminal through a fixed cable, a torsion actuator is installed at the bottom of the casing, and an imaging probe is installed on the torsion actuator. The lifting actuator is used to vertically place the casing and its connecting parts into the mud, one end of the movable cable is connected to the control terminal, and the other end of the movable cable is inserted into the casing and connected to the torsion actuator and the imaging probe respectively. The control terminal transmits action commands and collects data to the torsion actuator and the imaging probe through the movable cable, and the control terminal transmits action commands to the lifting actuator through the fixed cable. The beneficial effect of the present invention is that it can establish a three-dimensional modeling of the pile foundation hole wall, including the pile side and the pile bottom, and provide an evaluation for the pile foundation bearing capacity.

Description

Technical Field

[0001] The present invention relates to the technical field of pile foundation detection, and in particular to a pile foundation hole wall three-dimensional imaging device, a use method and an imaging method. Background Art

[0002] Traditional mud-wall pile foundations are prone to defects such as mud skin, sediment, shrinkage, and expansion. Their three-dimensional shape is inconsistent with the cylinder assumed during design, resulting in a large difference between the actual bearing capacity and the designed bearing capacity. Existing hole wall imaging using optical, laser, mechanical wave and other technologies is not suitable for pile holes of mud-wall piles. This is because there is a large amount of low-visibility mud in the pile hole, and the pile diameter is large, so it is difficult for mechanical waves to penetrate the mud and form reflections on the pile wall. In addition, existing devices are only used for the detection of pile walls and pile bottoms, that is, for local detection, and fail to achieve three-dimensional imaging of pile holes. For example: (1) A system and method for three-dimensional optical imaging of borehole walls CN114893171A: This invention is applied to geological drilling, and uses a lifting device and optical imaging to capture images of the borehole walls at different depths, and forms a three-dimensional image by stitching; (2) A system and method for three-dimensional geometric morphology measurement of borehole walls CN114964040A: This invention is applied to geological drilling, and uses a lifting device, laser, borehole wall projection imaging and other technologies to achieve three-dimensional imaging of the borehole wall. Summary of the invention

[0003] In order to solve the problems in the prior art, the present invention provides a pile foundation hole wall three-dimensional imaging device and a use method and an imaging method, which aim to clarify the three-dimensional shape of the pile foundation that may be formed after concrete is poured at the hole position, thereby providing reliable information for accurate evaluation of the pile foundation bearing capacity.

[0004] The present invention provides a three-dimensional imaging device for a pile foundation hole wall, comprising a reaction frame, a lifting actuator, a casing, a torsion actuator, an imaging probe, an active cable, a fixed cable, and a control terminal. The reaction frame is used to fix the lifting actuator, and the lifting actuator is connected to the control terminal through the fixed cable. The torsion actuator is installed at the bottom of the casing, and the imaging probe is installed on the torsion actuator. The lifting actuator is used to vertically place the casing and its connecting parts into mud. One end of the active cable is connected to the control terminal, and the other end of the active cable penetrates into the casing and is respectively connected to the torsion actuator and the imaging probe. The control terminal transmits action commands and collects data to the torsion actuator and the imaging probe through the active cable, and the control terminal transmits action commands to the lifting actuator through the fixed cable.

[0005] As a further improvement of the present invention, the sleeve is composed of a left half sleeve and a right half sleeve, and a vertical water stop is provided at the connection between the left half sleeve and the right half sleeve.

[0006] As a further improvement of the present invention, the pile foundation hole wall three-dimensional imaging device also includes a transverse water stop member, and the transverse water stop member is provided at the connection between two adjacent casings.

[0007] As a further improvement of the present invention, the imaging probe includes a machine top, a rotating shaft, a connecting rod, a detection rod, and a pressure sensor. The rotating shaft is installed in the machine top, and the rotating shaft is connected to the connecting rod. The rotating shaft can drive the connecting rod to rotate 180 degrees around it. The detection rod is installed in the connecting rod. The machine top provides hydraulic pressure for the detection rod to push the detection rod out of the connecting rod. The pressure sensor is installed at the bottom of the machine top, and the pressure sensor is used to detect whether the imaging probe has reached the bottom of the pile.

[0008] As a further improvement of the present invention, the pile foundation hole wall three-dimensional imaging device also includes a cable turntable, and the movable cable is wound on the cable turntable.

[0009] As a further improvement of the present invention, a first through hole is provided on the reaction frame, a second through hole is provided on the lifting actuator, the lifting actuator is installed on the reaction frame, the first through hole corresponds to the second through hole, the lifting actuator drives the casing to pass through the first through hole and the second through hole in sequence, and the casing and its connecting parts are vertically placed in the mud.

[0010] As a further improvement of the present invention, the vertical water stop member and the horizontal water stop member 34 are both made of rubber.

[0011] The present invention also discloses a method for using a pile foundation hole wall three-dimensional imaging device, comprising sequentially performing the following steps:

[0012] Step 1: The control terminal sets the data acquisition density to ρ, in points / square meter. Given the pile diameter R and pile length H, the imaging probe advances depth increment ΔH and azimuth increment The following relationship should be satisfied:

[0013]

[0014] The elevation angle increment Δθ of the connecting rod should satisfy the following relationship:

[0015]

[0016] Step 2: Push the casing and its connecting parts, the torsion actuator and the imaging probe downward by ΔH. If the pressure sensor reading does not increase significantly during this process, it indicates that the imaging probe has not touched the sediment at the bottom of the pile. At this time, the current depth of the imaging probe is recorded and the third step is executed; otherwise, the pile bottom has been reached and the pile side imaging has been completed, and the fifth step needs to be executed to complete the pile bottom imaging;

[0017] Step 3: Use the torsion actuator to rotate the imaging probe. The increment of the rotation angle is Then stop, record the azimuth of the current imaging probe, adjust the connecting rod to a horizontal state, and then control the detection rod to extend and penetrate the mud skin and soil inside the pile hole wall, and record the curve of penetration resistance and detection rod extension distance in this process. After completion, retract the detection rod to the connecting rod to remove the soil or mud attached to the detection rod. Repeat the above actions until the rotation angle of the torsion actuator reaches 360 degrees, that is, the pile side imaging at the current depth is completed, and the torsion actuator is returned to the initial state, and then return to the second step and continue to execute until the imaging probe touches the sediment at the bottom of the pile. During this process, add casing and release the active cable through the cable turntable to ensure that the imaging probe can reach the next depth;

[0018] Step 4: When the imaging probe reaches the bottom of the pile, the control terminal controls the lifting actuator to continue to move downward, so that the pressure sensor reading increases significantly. At this time, the lifting actuator stops moving downward, and then the imaging probe is lifted upward by the lifting actuator to return to the last imaging depth;

[0019] Step 5: Use the torsion actuator to rotate the imaging probe. The increment of the rotation angle is Then stop, at this time record the azimuth angle of the current imaging probe, at this azimuth angle, make the connecting rod rotate clockwise around the rotation axis, the increment of the rotation angle is Δθ, then stop, at this time record the elevation angle of the current connecting rod, then extend the detection rod and penetrate into the sediment and soil inside the wall of the pile hole, record the curve of penetration resistance and detection rod extension distance in this process, after completion, retract the detection rod to the connecting rod, so as to remove the soil or mud attached to the detection rod, repeat the above actions on the connecting rod and the detection rod until the angle of rotation of the connecting rod around the rotation axis reaches 180 degrees, that is, the imaging of the pile bottom at the current azimuth angle is completed, repeat the above actions on the torsion actuator, the connecting rod and the detection rod until the rotation angle of the torsion actuator reaches 180 degrees, that is, the imaging of the pile side at all azimuth angles is completed;

[0020] Step 6: After completing the pile bottom imaging, turn off all data acquisition, and slowly withdraw the casing, torsion actuator and imaging probe through the lifting actuator. During this process, the active cable is recovered through the cable turntable and each section of the casing is removed.

[0021] The present invention also discloses a pile foundation hole wall three-dimensional imaging method, comprising sequentially performing the following steps:

[0022] Step 1: Through the probe rod extension distance curve and the penetration resistance curve, determine the extension distance corresponding to the mud skin boundary and the soil boundary of each measuring point;

[0023] Step 2: Record different depths H for the pile side measurement points i , different azimuths Through analysis, we can get the extension distance of the detection rod corresponding to the mud skin side wall and the soil side wall as l bij and l sij ;

[0024] Step 3: Record the same depth H for the pile bottom measurement points e , different azimuths and different elevation angles θ j Through analysis, the distance between the detection rod and the sediment side wall is l bij and l sij Through the conversion relationship between spherical coordinates and rectangular coordinates, the coordinate positions of the sediment side wall and the soil side wall can be determined as and where θ j is the elevation angle of the probe rod;

[0025] Step 4: According to the coordinates of the mud skin side wall, the sediment side wall coordinates and the soil side wall coordinates, the triangulated networks of the mud skin side wall, the sediment side wall and the soil side wall are established respectively, that is, the three-dimensional imaging of the pile foundation hole wall is realized, so that the three-dimensional distribution of the mud skin thickness and the sediment thickness can be clearly determined, and the occurrence and location of defects such as shrinkage and expansion of the diameter can be determined through three-dimensional modeling.

[0026] As a further improvement of the present invention, in step 1, when the penetration resistance increases, it indicates that the probe rod penetrates the mud skin, and the turning point of the resistance corresponds to the side wall of the mud skin; when the penetration resistance slope increases, it indicates that the probe rod penetrates the soil body, and the turning point of the slope corresponds to the side wall of the soil body;

[0027] In step 2, the length of the connecting rod has been calibrated to be l, and the top of the pile is taken as the origin. Through the conversion relationship between cylindrical coordinates and rectangular coordinates, the coordinate positions of the mud skin side wall and the soil side wall can be determined to be and

[0028] The beneficial effects of the present invention are: 1. It can establish a three-dimensional model of the pile foundation hole wall, including the pile side and the pile bottom, to provide an evaluation of the pile foundation bearing capacity; 2. It can determine the thickness of the mud skin on the pile side and the sediment at the pile bottom through the changes in the push rod puncture resistance and its slope, and determine the location of the soil body, and the determination method has a physical basis; while the traditional method has a complex principle and cannot reflect the thickness of the mud skin and sediment; 3. It can set and adapt to different data collection densities. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a cross-sectional view of the pile foundation hole wall three-dimensional imaging device of the present invention;

[0030] Figure 2 It is a cross-sectional view of the casing of the pile foundation hole wall three-dimensional imaging device of the present invention;

[0031] Figure 3 This is a structural diagram of an imaging probe of a pile foundation hole wall three-dimensional imaging device of the present invention;

[0032] Figure 4 This is a diagram of the connection rod of the pile foundation hole wall three-dimensional imaging device of the present invention being adjusted to a horizontal state;

[0033] Figure 5 This is a diagram showing the state of the detection rod of the pile foundation hole wall three-dimensional imaging device of the present invention extending out and piercing into the hole wall;

[0034] Figure 6 This is a state diagram of the imaging probe of the pile foundation hole wall three-dimensional imaging device and its pressure sensor reaching the pile bottom;

[0035] Figure 7 It is a state diagram of the imaging probe of the pile foundation hole wall three-dimensional imaging device of the present invention returning to the last imaging depth;

[0036] Figure 8 It is a diagram showing the internal state of sediment and soil when the detection rod of the present invention extends out and penetrates into the hole wall; DETAILED DESCRIPTION

[0037] like Figure 1 As shown, the present invention discloses a pile foundation hole wall three-dimensional imaging device, including a reaction frame 1, a lifting actuator 2, a casing 3, a torsion actuator 4, an imaging probe 5, an active cable 6, a fixed cable 8, and a control terminal 9. The reaction frame 1 is used to fix the lifting actuator 2, and the lifting actuator 2 is connected to the control terminal 9 through the fixed cable 8. The torsion actuator 4 is installed at the bottom of the casing 3, and the imaging probe 5 is installed on the torsion actuator 4. The lifting actuator 2 is used to vertically place the casing 3 and its connecting parts into the mud. One end of the active cable 6 is connected to the control terminal 9, and the other end of the active cable 6 penetrates into the casing 3 and is respectively connected to the torsion actuator 4 and the imaging probe 5. The control terminal 9 transmits action commands and collects data to the torsion actuator 4 and the imaging probe 5 through the active cable 6, and the control terminal 9 transmits action commands to the lifting actuator 2 through the fixed cable 8.

[0038] The pile foundation hole wall three-dimensional imaging device further comprises a cable turntable 7 , on which the movable cable 6 is wound.

[0039] The reaction frame 1 is provided with a first through hole, the lifting actuator 2 is provided with a second through hole, the lifting actuator 2 is installed on the reaction frame 1, the first through hole corresponds to the second through hole, the lifting actuator 2 drives the casing 3 to pass through the first through hole and the second through hole in sequence, and the casing 3 and its connecting parts are vertically placed in the mud.

[0040] 1. Introduction to the device

[0041] The characteristics and functions of each part are introduced as follows:

[0042] (1) Reaction frame 1: used to fix the lifting actuator 2 and provide reaction force.

[0043] (2) Lifting actuator 2: used to vertically place the casing 3 and its connecting parts into the mud.

[0044] (3) Casing 3: Figure 2 As shown, it is composed of a left half casing 31 and a right half casing 32. To prevent mud from entering the casing 3, a vertical water stop 33 is set at the connection between the two. The casing 3 is hollow, allowing the active cable 6 to pass inside. At the same time, the casing 3 is allowed to be continuously increased to reach the specified test depth. To prevent mud from entering the casing, a horizontal water stop 34 is set at the connection between different casings 3. The casing 3 is annular, the horizontal water stop is annular rubber, and the vertical water stop 33 is vertical rubber.

[0045] (4) Torsion actuator 4: The torsion actuator 4 is connected to the bottom of the sleeve 3 and to the top of the imaging probe 5, and can enable the imaging probe 5 to rotate 360 ​​degrees.

[0046] (5) Imaging probe 5: It is the core component of the three-dimensional imaging device for pile foundation hole wall of the present invention, and is used to measure the three-dimensional imaging of the pile hole, such as Figure 3 As shown, it includes a machine top 51, a rotating shaft 52, a connecting rod 53, a detection rod 54 and a pressure sensor 55. The entire imaging probe 5 is well sealed to prevent the entry of mud.

[0047] Among them, the machine top 51 is connected to the torsion actuator 4 to provide hydraulic pressure for the detection rod 54 to push the detection rod 54 out of the connecting rod 53; the rotating shaft 52 can drive the connecting rod 53 to rotate 180 degrees around it; the pressure sensor 55 is used to detect whether the imaging probe 5 reaches the bottom of the pile; before the test, the length of the connecting rod 53 needs to be calibrated to l.

[0048] (6) Active cable 6: Passes through the hollow sleeve 3 and is connected to the torsion actuator 4 and the imaging probe 5 to transmit motion commands and collect data to these two components.

[0049] (7) Cable turntable 7: To adapt to different test depths, when a new casing 3 is added, it rotates to release more cables; conversely, after the casing 3 is removed, it rotates back to recover the excess cables.

[0050] (8) Fixed cable 8: used to connect the lifting actuator 2 and the control terminal 9, and transmit the action command to the lifting actuator 2.

[0051] (9) Control terminal 9: used to formulate action commands and transmit them to the specified object through the movable cable 6 and the fixed cable 8; at the same time, it receives and stores data through the movable cable 6; the data collection density can be set.

[0052] (10) The detected hole wall is generally composed of mud skin / sediment (the mud skin 10 located on the pile side and the sediment 12 located at the pile bottom) and soil 11.

[0053] 2. Installation process

[0054] The installation process is as follows:

[0055] Step 1: Install and fix the reaction frame 1 at the pile hole position so that the center of the pile hole is aligned with the center of the reaction frame 1 as much as possible; fix the lifting actuator 2 on the reaction frame 1; connect the lifting actuator 2 to the control terminal 9 through the fixed cable 8.

[0056] Step 2: Release a certain length of the movable cable 6 through the cable turntable 7, one end of the movable cable 6 is connected to the control terminal 9, and the other end is connected to the torsion actuator 4 and the imaging probe 5.

[0057] Step 3: Assemble the sleeve 3 and connect it to the torsion actuator 4 and the test probe 5 from top to bottom, and pass the active cable 6 through it.

[0058] Step 4: Pass the sleeve 3 and its connecting parts through the opening of the reaction frame 1 and the lifting actuator 2, ensuring verticality, and then wait until the test begins.

[0059] The present invention also discloses a method for using a pile foundation hole wall three-dimensional imaging device. The method is mainly divided into two cases: pile side imaging before reaching the pile bottom and pile bottom imaging after reaching the pile bottom. The specific steps are as follows:

[0060] Step 1: The control terminal 9 sets the data acquisition density to ρ, with the unit of points / square meter. Given that the pile diameter is R and the pile length is H, the imaging probe 5 advances the depth increment ΔH and the azimuth increment The following relationship should be satisfied:

[0061]

[0062] The elevation angle increment Δθ of the connecting rod 53 should satisfy the following relationship:

[0063]

[0064] Step 2: Push the casing 3 and its connecting parts (i.e., the torsion actuator 4 and the imaging probe 5) downward by ΔH. If the reading of the pressure sensor 55 does not increase significantly during this process, it indicates that the imaging probe 5 has not yet touched the pile bottom sediment 12. At this time, the current depth of the imaging probe 5 is recorded and the third step is executed; otherwise, the pile bottom has been reached and the pile side imaging has been completed, and the fifth step needs to be executed to complete the pile bottom imaging;

[0065] Step 3: Use the torsion actuator 4 to drive the imaging probe 5 to rotate, and the increment of the rotation angle is Then stop, record the current azimuth of the imaging probe 5, and adjust the connecting rod 53 to a horizontal state (such as Figure 4 Then, the detection rod 54 is controlled to extend and penetrate into the mud skin 10 and the soil body 11 of the pile hole wall (as shown in FIG. Figure 5 As shown), record the penetration resistance (i.e., the hydraulic pressure provided by the machine top 51) and the extension distance curve of the probe rod 54 during this process. After completion, retract the probe rod 54 to the connecting rod 53, so as to remove the soil or mud attached to the probe rod 54. Repeat the above actions until the rotation angle of the torsion actuator 4 reaches 360 degrees, that is, the pile side imaging at the current depth is completed, and the torsion actuator 4 is returned to the initial state, and then return to the second step and continue to execute until the imaging probe 5 touches the pile bottom sediment 12. During this process, the casing 3 is added and the active cable 6 is released through the cable turntable 7 to ensure that the imaging probe 5 can reach the next depth;

[0066] Step 4: When the imaging probe 5 reaches the bottom of the pile, the control terminal 9 controls the lifting actuator 2 to continue to move downward, so that the reading of the pressure sensor 55 increases significantly (such as Figure 6 As shown), at this time, the lifting actuator 2 is stopped from advancing downward, and then the imaging probe 5 is lifted upward by the lifting actuator 2 to return to the last imaging depth (as shown). Figure 7 shown);

[0067] Step 5: Use the torsion actuator 4 to drive the imaging probe 5 to rotate, and the increment of the rotation angle is Then stop, at this time record the azimuth angle of the current imaging probe 5, under this azimuth angle, make the connecting rod 53 rotate clockwise around the rotating shaft 52, the increment of the rotation angle is Δθ, then stop, at this time record the elevation angle of the current connecting rod 53, then extend the detection rod 54 and pierce the sediment 12 and the soil 11 of the pile hole wall (such as Figure 8As shown), the curve of penetration resistance and extension distance of the detection rod 54 is recorded during this process. After completion, the detection rod 54 is retracted to the connecting rod 53, so as to remove the soil or mud attached to the detection rod 54. The above actions on the connecting rod 53 and the detection rod 54 are repeated until the angle of rotation of the connecting rod 53 around the rotating shaft 52 reaches 180 degrees, that is, the pile bottom imaging at the current azimuth is completed. The above actions on the torsion actuator 4, the connecting rod 53 and the detection rod 54 are repeated until the rotation angle of the torsion actuator 4 reaches 180 degrees, that is, the pile side imaging at all azimuths is completed.

[0068] Step 6: After completing the pile bottom imaging, turn off all data acquisition, and slowly withdraw the casing 3, torsion actuator 4 and imaging probe 5 through the lifting actuator 2. During this process, the movable cable 6 is recovered through the cable turntable 7, and each section of the casing 3 is removed.

[0069] The present invention also discloses a pile foundation hole wall three-dimensional imaging method, comprising the following steps:

[0070] Step 1: The extending distance corresponding to the mud skin boundary and the soil body boundary of each measuring point is clarified through the extending distance curve of the probe rod 54 and the penetration resistance curve; when the penetration resistance increases, it indicates that the probe rod 54 penetrates the mud skin 10, and the turning point of this resistance corresponds to the side wall of the mud skin 10; when the slope of the penetration resistance increases, it indicates that the probe rod 54 penetrates the soil body, and the turning point of this slope corresponds to the side wall of the soil body;

[0071] Step 2: Record different depths H for the pile side measurement points i , different azimuths Through analysis, it is found that the extension distance of the detection rod 54 corresponding to the mud skin side wall and the soil side wall is l bij and l sij The length of the connecting rod 53 has been calibrated to be l, and the top of the pile is taken as the origin. Through the conversion relationship between cylindrical coordinates and rectangular coordinates, the coordinate positions of the mud skin side wall and the soil side wall can be determined respectively. and

[0072] Step 3: Record the same depth H for the pile bottom measurement points e , different azimuths and different elevation angles θ j Through analysis, it is found that the extension distance of the detection rod 54 corresponding to the sediment side wall and the soil side wall is l bij and l sij ; Through the conversion relationship between spherical coordinates and rectangular coordinates, the coordinate positions of the sediment side wall and the soil side wall can be determined as and where θ j is the elevation angle of the probe rod 54;

[0073] Step 4: According to the coordinates of the mud skin side wall, the sediment side wall coordinates and the soil side wall coordinates, the triangulated networks of the mud skin side wall, the sediment side wall and the soil side wall are established respectively, that is, the three-dimensional imaging of the pile foundation hole wall is realized, so that the three-dimensional distribution of the mud skin thickness and the sediment thickness can be clearly determined, and the occurrence and location of defects such as shrinkage and expansion of the diameter can be determined through three-dimensional modeling.

[0074] The advantages of the present invention are as follows: 1. It can establish a three-dimensional model of the pile foundation hole wall, including the pile side and the pile bottom, to provide an evaluation of the pile foundation bearing capacity; 2. It can determine the thickness of the mud skin on the pile side and the sediment at the pile bottom through the changes in the push rod puncture resistance and its slope, and determine the location of the soil body, and the determination method has a physical basis; while the traditional method has a complex principle and cannot reflect the thickness of the mud skin and sediment; 3. It can set and adapt to different data collection densities.

[0075] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A method for using a pile foundation hole wall three-dimensional imaging device, using the pile foundation hole wall three-dimensional imaging device, the pile foundation hole wall three-dimensional imaging device comprising a reaction frame (1), a lifting actuator (2), a casing (3), a torsion actuator (4), an imaging probe (5), an active cable (6), a fixed cable (8), and a control terminal (9), wherein the imaging probe (5) is installed on the torsion actuator (4), the lifting actuator (2) is used to vertically place the casing (3) and its connecting parts into mud, the active cable (6) is respectively connected to the control terminal (9), the torsion actuator (4), and the imaging probe (5), and the control terminal (9) transmits action commands and Collecting data; the imaging probe (5) comprises a machine top (51), a rotating shaft (52), a connecting rod (53), a detection rod (54), and a pressure sensor (55); the rotating shaft (52) is installed in the machine top (51); the rotating shaft (52) is connected to the connecting rod (53); the rotating shaft (52) can drive the connecting rod (53) to rotate 180 degrees around it; the detection rod (54) is installed in the connecting rod (53); the machine top (51) provides hydraulic pressure for the detection rod (54) to push the detection rod (54) out of the connecting rod (53); the pressure sensor (55) is installed at the bottom of the machine top (51); the pressure sensor (55) is used to detect whether the imaging probe (5) reaches the bottom of the pile, characterized in that, It includes performing the following steps in sequence: Step 1: The control terminal (9) sets the data acquisition density to ρ, with the unit being points / square meter. Given that the pile diameter is R and the pile length is H, the imaging probe (5) advances the depth increment ΔH and the azimuth increment The following relationship should be satisfied: The elevation angle increment Δθ of the connecting rod (53) should satisfy the following relationship: Step 2: Push the casing (3) and its connecting parts, the torsion actuator (4) and the imaging probe (5) downward by ΔH. If the reading of the pressure sensor (55) does not increase significantly during this process, it indicates that the imaging probe (5) has not yet touched the pile bottom sediment (12). At this time, the current depth of the imaging probe (5) is recorded and the third step is executed. Otherwise, the pile bottom has been reached and the pile side imaging has been completed. The fifth step is required to complete the pile bottom imaging. Step 3: Use the torsion actuator (4) to drive the imaging probe (5) to rotate, and the increment of the rotation angle is Then stop, record the azimuth angle of the current imaging probe (5), adjust the connecting rod (53) to a horizontal state, then control the detection rod (54) to extend and penetrate into the mud skin (10) and soil (11) of the pile hole wall, and record the curve of penetration resistance and detection rod (54) extension distance in this process. After completion, retract the detection rod (54) to the connecting rod (53), thereby removing the soil or mud attached to the detection rod (54). Repeat the above actions until the rotation angle of the torsion actuator (4) reaches 360 degrees, that is, the pile side imaging at the current depth is completed, and the torsion actuator (4) is returned to the initial state, and then return to the second step and continue to execute until the imaging probe (5) touches the pile bottom sediment (12). During this process, add a casing (3) and release the movable cable (6) through the cable turntable (7) to ensure that the imaging probe (5) can reach the next depth; Step 4: When the imaging probe (5) reaches the bottom of the pile, the control terminal (9) controls the lifting actuator (2) to continue to move downward, so that the reading of the pressure sensor (55) increases significantly. At this time, the lifting actuator (2) stops moving downward, and then the imaging probe (5) is lifted upward by the lifting actuator (2) to return to the last imaging depth; Step 5: Use the torsion actuator (4) to drive the imaging probe (5) to rotate, and the increment of the rotation angle is Then stop, at which time the azimuth angle of the current imaging probe (5) is recorded. At this azimuth angle, the connecting rod (53) is rotated clockwise around the rotating shaft (52), and the increment of the rotation angle is Δθ. Then stop, at which time the elevation angle of the current connecting rod (53) is recorded. Then the detection rod (54) is extended and inserted into the sediment (12) and the soil (11) on the wall of the pile hole, and the curve of the penetration resistance and the extension distance of the detection rod (54) is recorded. After completion, the detection rod (54) is retracted to the connecting rod (53), thereby removing the soil or mud attached to the detection rod (54), repeating the above actions on the connecting rod (53) and the detection rod (54), until the angle of rotation of the connecting rod (53) around the rotation axis (52) reaches 180 degrees, that is, the pile bottom imaging at the current azimuth is completed, repeating the above actions on the torsion actuator (4), the connecting rod (53) and the detection rod (54), until the angle of rotation of the torsion actuator (4) reaches 180 degrees, that is, the pile side imaging at all azimuths is completed; Step 6: After the pile bottom imaging is completed, all data acquisition is turned off, and the casing (3), the torsion actuator (4) and the imaging probe (5) are slowly withdrawn through the lifting actuator (2). During this process, the movable cable (6) is recovered through the cable turntable (7), and each section of the casing (3) is removed.

2. A method for three-dimensional imaging of a pile foundation hole wall according to the method of claim 1, characterized in that: It includes performing the following steps in sequence: Step 1: By using the extension distance curve of the probe rod (54) and the penetration resistance curve, the extension distance corresponding to the mud skin boundary and the soil boundary of each measuring point is determined; Step 2: Record different depths H for the pile side measurement points i , different azimuths Through analysis The detection rod (54) extending to the mud skin side wall and the soil body side wall is lbij and lsij respectively; Step 3: Record the same depth He and different azimuths for the pile bottom measurement points and different elevation angles θj, the extended distances of the detection rod (54) corresponding to the sediment side wall and the soil side wall are obtained by analysis as lbij and lsij, and the coordinate positions of the sediment side wall and the soil side wall can be determined by the conversion relationship between spherical coordinates and rectangular coordinates as follows: and Where θj is the elevation angle of the probe rod (54); Step 4: According to the coordinates of the mud skin side wall, the sediment side wall coordinates and the soil side wall coordinates, the triangulated networks of the mud skin side wall, the sediment side wall and the soil side wall are established respectively, that is, the three-dimensional imaging of the pile foundation hole wall is realized, so that the three-dimensional distribution of the mud skin thickness and the sediment thickness can be clarified, and the presence and location of the shrinkage and expansion defects can be clarified through three-dimensional modeling; In step 1, when the penetration resistance increases, it indicates that the probe rod (54) penetrates the mud skin (10), and the turning point of the resistance corresponds to the side wall of the mud skin (10); when the penetration resistance slope increases, it indicates that the probe rod (54) penetrates the soil body, and the turning point of the slope corresponds to the side wall of the soil body; In step 2, the length of the connecting rod (53) is calibrated to be l, and the top of the pile is taken as the origin. Through the conversion relationship between cylindrical coordinates and rectangular coordinates, the coordinate positions of the mud skin side wall and the soil side wall can be determined to be and

Images