CN212534238U

CN212534238U - Pile foundation low strain dynamic tester

Info

Publication number: CN212534238U
Application number: CN202021144107.0U
Authority: CN
Inventors: 朱长亮; 傅明波; 张振伟
Original assignee: Hangzhou Dadi Engineering Testing Technology Co ltd
Current assignee: Hangzhou Dadi Engineering Testing Technology Co ltd
Priority date: 2020-06-18
Filing date: 2020-06-18
Publication date: 2021-02-12
Anticipated expiration: 2030-06-18

Abstract

The utility model relates to a pile foundation detection area, especially, relate to pile foundation low strain dynamic testing appearance, which comprises a probe, connecting wire and host computer, the below of host computer is provided with the bottom plate, one of bottom plate serves to be provided with two and is used for fixing the joint spare that is difficult to rock on the bottom plate with the host computer, the other end of bottom plate is fixed with the first board that is vertical setting, be fixed with the second board on the up end of first board, the second board is perpendicular setting with the first board, be fixed with reciprocal lead screw between second board and the bottom plate, be provided with the installation piece on the reciprocal lead screw, be provided with between installation piece and the first board and be used for restricting the locating part that the installation piece can only remove along vertical direction, the installation piece is cavity setting, be provided with the first driving piece that is used for driving the vertical slip of installation piece on the installation piece, be provided with the piece that strikes off that is used: be convenient for clean with the earth on the pile foundation outer wall for measuring result is more accurate.

Description

Pile foundation low strain dynamic tester

Technical Field

The utility model belongs to the technical field of the technique that the pile foundation detected and specifically relates to a pile foundation hangs down and meets an emergency electrometer.

Background

The low strain dynamic measurement method is characterized in that a small hammer is used for knocking the pile top, a sensor bonded to the pile top is used for receiving stress wave signals from the pile, the dynamic response of a pile-soil system is researched by adopting a stress wave theory, and actually measured speed signals and frequency signals are subjected to inversion analysis, so that the integrity of the pile is obtained. The method is simple and convenient to detect, and the detection speed is high, but the key of the detection work is how to obtain a good waveform and how to better analyze the integrity of the pile body. In the detection, it does not have ponding to need the pile foundation surface to preserve the drying, but has ponding in detecting a bit to some pile foundation surfaces cover has tiny granule such as dust, influences the testing effect.

Therefore, chinese patent with publication number CN208219721U discloses a low strain dynamic tester for pile foundation, which comprises a probe, a connecting wire and a host, wherein the probe passes through the connecting wire and is connected with the host, a signal line and an air pipe are arranged in the connecting wire, a sensor and an air outlet are arranged in the probe, a controller, a display, an air pump and a heating pipe are arranged in the host, a heating wire is arranged in the heating pipe, the air outlet of the air pump is connected with the heating pipe, the heating pipe passes through the air pipe and the air outlet, the controller passes through the signal line and the sensor is connected, and the display is connected with the controller. And drying the surface of the pile foundation by using the probe, and thoroughly removing accumulated water. The air is heated by the electric heating wire in the heating pipe, and the evaporation of the moisture on the undried position of the surface of the pile foundation is promoted by continuously blowing high-temperature gas to the surface of the pile foundation. And meanwhile, fine particles on the surface of the pile foundation can be removed, firm pile foundation parts are leaked, and the detection accuracy is improved.

But above-mentioned pile foundation low strain mobility tester has a bit weak point to be located, and this pile foundation low strain mobility tester can only clear away some tiny particulate matters on pile foundation surface, to some firm clay pieces of adhesion, can not clear away these clay pieces through blowing to the pile foundation surface, and the existence of these clay pieces still can make the accuracy of detection not high.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a low dynamic testing appearance that meets an emergency of pile foundation, thereby have the effect of cleaing away the accuracy that improves the detection to pile foundation surface adhered to earth piece.

The above utility model discloses an above-mentioned utility model purpose can realize through following technical scheme:

the low-strain dynamic tester for the pile foundation comprises a probe, a connecting wire and a host, wherein a bottom plate is arranged below the host, two clamping pieces which are used for fixing the main machine on the bottom plate and are difficult to shake are arranged on the upper surface of one end of the bottom plate, a first plate which is vertically arranged is fixed on the upper surface of the other end of the bottom plate, a second plate is fixed on the upper end surface of the first plate, the second plate is vertical to the first plate, a reciprocating screw rod is vertically arranged between the second plate and the bottom plate, the reciprocating screw rod is provided with an installation block, a limiting piece used for limiting the installation block to move only along the vertical direction is arranged between the installation block and the first plate, the installation piece is cavity setting, be provided with the first driving piece that is used for driving the vertical slip of installation piece on the installation piece, one side of first board is provided with the piece that strikes off that is used for cleaing away earth on the pile foundation outer wall outward.

Through adopting above-mentioned technical scheme, before testing the pile foundation, pass through joint spare in advance, fix the host computer on the bottom plate for the host computer is difficult to rock, through first driving piece, under the effect of locating part, makes the vertical slip of installation piece, and the installation piece is at the process of vertical slip, thereby through striking off the piece, clean the earth on the pile foundation outer wall, thereby make measuring result more accurate.

The utility model discloses further set up to: strike off the piece including fixing the mounting panel on the installation piece outer wall, fixing the annular plate that the installation piece one end was kept away from to the mounting panel, fixing ball bearing on the annular plate inner wall, fixing the brush board that scrapes cover, a plurality of that are vertical setting on the ball bearing inner wall and fix on scraping the inner wall of cover, the mounting panel is perpendicular setting with the first board, the axis and the vertical direction of annular plate are parallel arrangement, a plurality of the brush board is circular distribution round the axis of scraping the cover, still be provided with on the installation piece and be used for the drive to scrape cover pivoted second driving piece.

Through adopting above-mentioned technical scheme, when needs are cleaned the earth on the pile foundation, will scrape in advance under the cover from the top of pile foundation, slide from top to bottom through first driving piece drive installation piece is vertical to make the mounting panel slide from top to bottom together vertically, the mounting panel is at vertical gliding process, under the effect of second driving piece, the brush board strikes off earth on with the pile foundation outer wall from the upper end to the bottom of pile foundation, thereby makes the outer wall of pile foundation become clean.

The utility model discloses further set up to: first driving piece is including rotating axle sleeve, the coaxial worm wheel of fixing on the axle sleeve outer wall on the installation piece inner wall, rotating the worm on the installation piece inner wall, fixing the servo motor on installation piece one side outer wall, reciprocal lead screw wears to establish on the installation piece, installation piece and reciprocal lead screw sliding connection, axle sleeve and reciprocal lead screw threaded connection, worm meshing worm wheel, servo motor's pivot coaxial fixation is in the pivot of worm.

Through adopting above-mentioned technical scheme, servo motor's pivot is rotated, and worm meshing worm wheel rotates, and the worm wheel rotates together with the axle sleeve to make whole installation piece along reciprocating screw's axis vertical migration.

The utility model discloses further set up to: the second driving piece includes that the coaxial fixation scrapes the first gear on the cover lower extreme outer wall, rotates second gear, coaxial fixation third gear on the second gear wheel pivot, the coaxial fourth gear of fixing on the axle sleeve outer wall, seting up the installation piece towards the third gear one side keep away the position hole, around the hold-in range of rolling up on third gear and fourth gear on the mounting panel lower surface, first gear and second gear engagement, the third gear is located the top of second gear, the hold-in range is located keeps away the position downthehole.

Through adopting above-mentioned technical scheme, the installation piece is at the vertical in-process that slides, and the axle sleeve rotates to make fourth gear revolve, under the effect of hold-in range, fourth gear and third gear rotate together, thereby make third gear and second gear coaxial rotation together, second gear meshing first gear revolve, thereby first gear with scrape the cover and rotate together, thereby make and scrape the cover at the vertical in-process that reciprocates, self also rotates together, simple structure is ingenious.

The utility model discloses further set up to: the locating part includes the dovetail of seting up in first board and being close to reciprocal lead screw one side, fixes the forked tail piece that is close to mounting panel one side at the mounting block, the forked tail piece slides in the dovetail.

Through adopting above-mentioned technical scheme, when the vertical reciprocating of drive installation piece, the installation piece can only be along the vertical slip of the length direction of dovetail, and the installation piece is difficult to appear deflecting among the slip process, has strengthened the gliding stability of installation piece.

The utility model discloses further set up to: the joint spare is including seting up recess on the bottom plate upper surface, the butt piece of slip in the recess, setting spring in the recess, fixing the down tube on butt piece upper surface, fixing and keeping away from the splint that butt piece one end is vertical setting at the down tube, the host computer is located between two recesses, the length direction of recess is parallel arrangement with the length direction of bottom plate, spring one end is fixed on the one end inner wall of recess towards the host computer, the spring other end is fixed on the butt piece, contained angle between the length direction of down tube and recess is the acute angle setting, two the down tube is the symmetry setting, the one side butt that the down tube was kept away from to splint is on the outer wall of host computer, the host computer centre gripping is between two splint.

Through adopting above-mentioned technical scheme, when fixing the host computer on the bottom plate, at first the pulling down tube for two splint slide to the back, the in-process of pulling, the spring is compressed gradually, then places the host computer between two splint, loosens the down tube, under the effect of spring restoring force, makes the organism pressed from both sides tightly by two splint, thereby the organism just is difficult to rock, makes the host computer be difficult to the incident that appears dropping in the testing process.

The utility model discloses further set up to: and a rubber pad is fixed on one side of the clamping plate, which is attached to the side wall of the main machine.

Through adopting above-mentioned technical scheme, the rubber pad makes to be difficult to direct contact between splint and the host computer, because the rubber pad belongs to the flexibility, has reduced the wearing and tearing of splint to the host computer, and the rubber pad has increased the friction between splint and the host computer simultaneously for the host computer is fixed and is difficult to rock on the bottom plate.

The utility model discloses further set up to: the lower end of the scraping sleeve is arranged in a flaring manner.

By adopting the technical scheme, the scraping sleeve is convenient to be sleeved on the pile foundation.

To sum up, the utility model discloses a beneficial technological effect does: the soil on the outer wall of the pile foundation is convenient to clean, so that the measurement result is more accurate; by arranging the dovetail groove and the dovetail block, the mounting block can only vertically slide along the length direction of the dovetail groove, and the mounting block is difficult to deflect in the sliding process, so that the sliding stability of the mounting block is enhanced; by arranging the two clamping plates, the host is difficult to fall off in the test process; through setting up the rubber pad, reduced the wearing and tearing of splint to the host computer.

Drawings

FIG. 1 is a schematic view of the overall structure of the present embodiment;

fig. 2 is a schematic view of the overall structure of the clip of the present embodiment;

fig. 3 is a schematic view of the overall structure of the first driving member and the second driving member of the present embodiment.

Reference numerals: 1. a probe; 2. a connecting wire; 3. a host; 4. a base plate; 5. a clamping piece; 6. a first plate; 7. a second plate; 8. a reciprocating screw; 9. mounting blocks; 10. a limiting member; 11. a first driving member; 12. a scraping member; 13. mounting a plate; 14. an annular plate; 15. a ball bearing; 16. scraping the sleeve; 17. a brush plate; 18. a second driving member; 19. a shaft sleeve; 20. a worm gear; 21. a worm; 22. a servo motor; 23. a first gear; 24. a second gear; 25. a third gear; 26. a fourth gear; 27. avoiding holes; 28. a synchronous belt; 29. a dovetail groove; 30. a dovetail block; 31. a groove; 32. a butting block; 33. a spring; 34. a diagonal bar; 35. a splint; 36. and (7) a rubber pad.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1, for the utility model discloses a low dynamic electricity meter that meets an emergency of pile foundation, including probe 1, connecting wire 2 and host computer 3, the below of host computer 3 is provided with bottom plate 4, and host computer 3 is placed on bottom plate 4, and connecting wire 2 is used for connecting host computer 3 and probe 1, and the in-process of test is with probe 1 butt on the outer wall of pile foundation, then uses the hammer to strike the pile foundation to just the fluctuation curve that meets an emergency that produces after strikeing has appeared on the display screen of host computer 3.

As shown in fig. 2, two clamping members 5 for fixing the host 3 on the bottom plate 4 and being difficult to shake are arranged on the upper surface of one end of the bottom plate 4, the host 3 is located between the two clamping members 5, each clamping member 5 comprises a groove 31, an abutting block 32, a spring 33, an inclined rod 34 and a clamping plate 35, the groove 31 is arranged on the upper surface of the bottom plate 4, the length direction of the groove 31 is parallel to the length direction of the bottom plate 4, the host 3 is located between the two grooves 31, the abutting block 32 slides in the groove 31 along the length direction of the groove 31, the spring 33 is arranged in the groove 31, one end of the spring 33 is fixed on the inner wall of one end of the groove 31 facing the host 3, the other end of the spring 33 is fixed on one side of the abutting block 32 away from the machine body, one end of the inclined rod 34 is fixed on the upper surface of the abutting block 32, the other end of the inclined rod 34 inclines towards the direction close to the host 3, the, splint 35 is vertical setting, splint 35 is fixed and is kept away from the one end of butt piece 32 at down tube 34, one side that down tube 34 was kept away from to splint 35 is fixed with rubber pad 36, rubber pad 36 has reduced splint 35 to the wearing and tearing of host computer 3, when needing to fix host computer 3 on bottom plate 4, at first spur down tube 34, make two splint 35 slide dorsad, the in-process of pulling, spring 33 is compressed gradually, then place host computer 3 between two splint 35, loosen down tube 34, under the effect of spring 33 restoring force, make the organism pressed from both sides tightly by two splint 35, thereby the organism just is difficult to rock, in the test procedure has been promoted, the stability of organism.

As shown in fig. 3, a first plate 6 is fixed on the upper surface of the other end of the bottom plate 4, the first plate 6 is vertically arranged, a second plate 7 is fixed on the upper end surface of the first plate 6, the first plate 6 and the second plate 7 are vertically arranged, a reciprocating lead screw 8 is fixed between the second plate 7 and the bottom plate 4, a mounting block 9 is arranged on the reciprocating lead screw 8, a limiting member 10 for limiting the mounting block 9 to move only along the vertical direction is arranged between the mounting block 9 and the first plate 6, the limiting member 10 comprises a dovetail groove 29 and a dovetail block 30, the dovetail groove 29 is arranged on one side of the first plate 6 close to the reciprocating lead screw 8, the dovetail block 30 is fixed on the mounting block 9, the dovetail block 30 slides in the dovetail groove 29, when the mounting block 9 is driven to vertically move up and down, the mounting block 9 can only vertically slide along the length direction of the dovetail groove 29, and the mounting block 9 is difficult to deflect during the sliding process, so that the mounting block 9 slides more stably.

As shown in fig. 3, the mounting block 9 is hollow, a first driving member 11 for driving the mounting block 9 to vertically slide is disposed on the mounting block 9, the first driving member 11 includes a shaft sleeve 19, a worm wheel 20, a worm 21 and a servo motor 22, the reciprocating lead screw 8 is disposed on the mounting block 9, the mounting block 9 is slidably connected along the axial direction of the reciprocating lead screw 8, the shaft sleeve 19 is rotatably connected to the inner wall of the mounting block 9, the inner wall of the shaft sleeve 19 is in threaded connection with the reciprocating lead screw 8, the worm wheel 20 is coaxially fixed on the outer wall of the shaft sleeve 19, the worm 21 is rotatably connected to the mounting block 9, the worm 21 is engaged with the worm wheel 20, the rotating shaft of the servo motor 22 is coaxially and fixedly connected with the rotating shaft of the worm 21, the servo motor 22 is fixed on the outer wall of the mounting block 9, when it is necessary to drive the mounting block 9 to vertically slide along the axial line of the reciprocating, the worm gear 20 rotates with the bushing 19, causing the entire mounting block 9 to move vertically along the axis of the reciprocating lead screw 8.

As shown in fig. 3, one side of first board 6 is provided with outward and is used for cleaing away scraping the piece 12 that strikes off earth on the pile foundation outer wall, it includes mounting panel 13 to strike off a 12, annular plate 14, ball bearing 15, scrape cover 16 and brush board 17, mounting panel 13 is perpendicular setting with first board 6, mounting panel 13 is fixed on the one side outer wall that first board 6 was kept away from to installation piece 9, annular plate 14 is fixed on the one end terminal surface that installation piece 9 was kept away from to mounting panel 13, the axis and the vertical direction of annular plate 14 are parallel arrangement, ball bearing 15 is coaxial to be fixed on the inner wall of annular plate 14, the outer wall of scraping cover 16 is fixed on ball bearing 15's inner wall, the lower extreme of scraping cover 16 is the flaring setting, a plurality of brush board 17 is all fixed on the inner wall of scraping cover 16, a plurality of brush board 17 is circular distribution around the axis.

As shown in fig. 3, the mounting block 9 is further provided with a second driving member 18 for driving the scraping sleeve 16 to rotate, the second driving member 18 includes a first gear 23, a second gear 24, a third gear 25, a fourth gear 26, a spacing hole 27 and a synchronous belt 28, the first gear 23 is coaxially fixed on the outer wall of the lower end of the scraping sleeve 16, the second gear 24 is rotatably connected on the lower surface of the mounting block 13, the second gear 24 is meshed with the first gear 23, the third gear 25 is coaxially fixed on the rotating shaft of the second gear 24, the third gear 25 is located above the second gear 24, the fourth gear 26 is coaxially fixed on the outer wall of the shaft sleeve 19, the spacing hole 27 is opened on one side of the mounting block 9 close to the third gear 25, the spacing hole 27 is communicated with the inner cavity of the mounting block 9, the synchronous belt 28 is wound on the third gear 25 and the fourth gear 26, when soil on the outer wall of the pile foundation is removed, the scraping sleeve 16 is firstly sleeved on the outer wall of the pile foundation, make the brush laminating of brush board 17 on the outer wall of pile foundation, then start servo motor 22, make installation piece 9 drive scrape the vertical up-and-down reciprocating motion of cover 16, installation piece 9 is at the vertical in-process that slides, axle sleeve 19 rotates, thereby make fourth gear 26 rotate, under the effect of hold-in range 28, fourth gear 26 rotates together with third gear 25, thereby make third gear 25 and second gear 24 coaxial rotation together, second gear 24 is meshing first gear 23 and is rotating, thereby first gear 23 rotates together with scraping cover 16, thereby make and scrape the in-process that cover 16 reciprocated vertically, self also rotates together, thereby it is clean up with the earth on the pile foundation outer wall more easily.

The implementation principle of the embodiment is as follows: firstly, the main machine 3 is clamped between two clamping plates 35, before the low-strain movement of the pile foundation is tested, soil and dust are attached to the outer wall of the pile foundation, at the moment, the scraping sleeve 16 is sleeved on the outer wall of the pile foundation, the brush of the brush plate 17 is attached to the outer wall of the pile foundation, then the servo motor 22 is started, the rotating shaft of the servo motor 22 rotates, the worm 21 is meshed with the worm wheel 20 to rotate, the worm wheel 20 rotates together with the shaft sleeve 19, so that the whole mounting block 9 vertically moves along the axis of the reciprocating screw 8, the shaft sleeve 19 rotates in the vertical sliding process of the mounting block 9, so that the fourth gear 26 rotates, under the action of the synchronous belt 28, the fourth gear 26 rotates together with the third gear 25, so that the third gear 25 coaxially rotates together with the second gear 24, the second gear 24 is meshed with the first gear 23 to rotate, so that the first gear 23 rotates together with the scraping sleeve 16, thereby make and scrape cover 16 at the vertical in-process that reciprocates, self also rotates together to just, scrape the earth that will adhere to on the pile foundation outer wall and sweep, strike off the back that finishes, will scrape cover 16 and take out from the pile foundation, then use probe 1 to aim at the pile foundation and blow hot-blast and stoving, dry the water on pile foundation surface and blow away the tiny granule on pile foundation surface, thereby the data that measure are just more accurate.

The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. Pile foundation hangs down dynamic measurement appearance that meets an emergency, including probe (1), connecting wire (2) and host computer (3), its characterized in that: the utility model discloses a portable electronic device, including host computer (3), be provided with bottom plate (4) below of host computer (3), be provided with on the one end upper surface of bottom plate (4) two and be used for fixing joint spare (5) that are difficult to rock on bottom plate (4) with host computer (3), be fixed with first board (6) that are vertical setting on the other end upper surface of bottom plate (4), be fixed with second board (7) on the up end of first board (6), second board (7) are perpendicular setting with first board (6), be fixed with between second board (7) and bottom plate (4) and be vertical reciprocal lead screw (8) that sets up, be provided with installation piece (9) on reciprocal lead screw (8), be provided with between installation piece (9) and first board (6) and be used for restricting that installation piece (9) can only be along locating part (10) that vertical direction removed, installation piece (9) are the cavity setting, be provided with on installation piece (9) and be used for driving the first (5) that drive installation piece (9) are vertical slides 11) And a scraping piece (12) for removing soil on the outer wall of the pile foundation is arranged outside one side of the first plate (6).

2. The low-strain dynameter for pile foundation of claim 1, characterized in that: strike off piece (12) including fixing mounting panel (13) on installation piece (9) outer wall, fixing annular plate (14) of keeping away from installation piece (9) one end in mounting panel (13), fixing ball bearing (15) on annular plate (14) inner wall, fixing and be vertical setting scrape cover (16), a plurality of on ball bearing (15) inner wall and fix brush board (17) of scraping on cover (16) inner wall, mounting panel (13) are perpendicular setting with first board (6), the axis and the vertical direction of annular plate (14) are parallel arrangement, a plurality of brush board (17) are circular distribution round the axis of scraping cover (16), still be provided with on installation piece (9) and be used for the drive to scrape cover (16) pivoted second driving piece (18).

3. The low-strain dynameter for pile foundation of claim 2, wherein: first driving piece (11) including rotate axle sleeve (19) on installation piece (9) inner wall, coaxial worm wheel (20) of fixing on axle sleeve (19) outer wall, rotate worm (21) on installation piece (9) inner wall, fix servo motor (22) on installation piece (9) one side outer wall, reciprocal lead screw (8) are worn to establish on installation piece (9), installation piece (9) and reciprocal lead screw (8) sliding connection, axle sleeve (19) and reciprocal lead screw (8) threaded connection, worm (21) meshing worm wheel (20), the pivot coaxial fixation of servo motor (22) is in the pivot of worm (21).

4. The low-strain dynameter for pile foundation of claim 3, wherein: second driving piece (18) including coaxial fixation scrape first gear (23) on cover (16) lower extreme outer wall, rotate on mounting panel (13) lower surface second gear (24), coaxial fixation in second gear (24) pivot third gear (25), coaxial fixation fourth gear (26) on axle sleeve (19) outer wall, set up in installation piece (9) towards third gear (25) one side keep away a hole (27), around rolling up hold-in range (28) on third gear (25) and fourth gear (26), first gear (23) and second gear (24) meshing, third gear (25) are located the top of second gear (24), hold-in range (28) are located and keep away in hole (27).

5. The low-strain dynameter for pile foundation of claim 1, characterized in that: the limiting piece (10) comprises a dovetail groove (29) formed in one side, close to the reciprocating screw rod (8), of the first plate (6) and a dovetail block (30) fixed to one side, close to the mounting plate (13), of the mounting block (9), and the dovetail block (30) slides in the dovetail groove (29).

6. The low-strain dynameter for pile foundation of claim 1, characterized in that: the clamping piece (5) comprises a groove (31) formed in the upper surface of the base plate (4), a butt joint block (32) sliding in the groove (31), a spring (33) arranged in the groove (31), an inclined rod (34) fixed on the upper surface of the butt joint block (32), and a clamp plate (35) fixed on the inclined rod (34) and far away from one end of the butt joint block (32) to form a vertical arrangement, the host (3) is positioned between the two grooves (31), the length direction of the groove (31) and the length direction of the base plate (4) are arranged in parallel, one end of the spring (33) is fixed on the inner wall of one end of the groove (31) facing the host (3), the other end of the spring (33) is fixed on the butt joint block (32), an included angle between the inclined rod (34) and the length direction of the groove (31) is arranged in an acute angle, the two inclined rods (34) are symmetrically arranged, one side of the inclined rod (34) far away from the clamp plate (35) is abutted to the outer wall of the host (3, the main machine (3) is clamped between two clamping plates (35).

7. The low-strain dynameter for pile foundation of claim 6, wherein: and a rubber pad (36) is fixed on one side of the clamping plate (35) which is attached to the side wall of the main machine (3).

8. The low-strain dynameter for pile foundation of claim 2, wherein: the lower end of the scraping sleeve (16) is arranged in a flaring manner.