Collapsing formation casing hammer drag reduction pipe and vibration pipe pile pile collaborative construction method

Abstract

The present application relates to the technical field of pile foundation engineering, and discloses a pile forming method for easy-collapsing stratum casing hammering resistance reduction sinking and vibration pipe pulling, which forms an annular resistance reduction gap through a specially-made pile shoe with an outer diameter larger than that of the casing, thereby reducing the sinking pipe friction resistance and preventing hole collapse; a walking pile machine with upper and lower limiting hoops is used to cooperate with a single-section super-long casing, so as to precisely control the verticality of the sinking pipe; the machine is moved to continue sinking the pipe after the pipe is sunk to 2 / 3 of the depth; a reinforcement cage is hoisted at a high position and fixed by using a built-in anti-floating component of the pile shoe, and then concrete is poured at a high position, so as to compact the pile by vibration and pipe pulling with a hydraulic vibration hammer; one machine, two casings and three hoists are used for flow operation, so as to realize parallel and continuous construction of two pile positions; the present application effectively solves the problems of hole collapse, high friction resistance, loss of control of verticality, reinforcement cage floating and low process efficiency in easy-collapsing stratum, and has stable pile forming quality, high construction efficiency, low equipment and labor cost, and is suitable for pile foundation construction in deep fill, loose sand and other easy-collapsing strata.

Description

Technical Field

[0001] This invention relates to the technical field of pile foundation engineering, and more specifically, to a method for the coordinated construction of pile foundations in easily collapsible strata using casing hammering for drag reduction and vibratory pipe pulling. Background Technology

[0002] Driven piles are widely used in pile foundation engineering due to their convenient construction and moderate cost. However, when constructing driven piles in easily collapsible strata such as deep fill, loose sand, and soft plastic cohesive soil, traditional techniques have many insurmountable technical drawbacks: Traditional pipe-sinking construction uses conventional pile shoes with the same diameter as the casing. During the pipe-sinking process, the outer wall of the casing is directly in close contact with the soil of the borehole wall. The side wall friction of the casing is large, making pipe-sinking difficult, easy to get stuck, and unable to form an effective protective wall. The borehole wall is prone to collapse, causing quality defects such as diameter reduction, broken piles, and mud inclusion.

[0003] During the concrete pouring stage, the buoyancy generated by the rising concrete can easily cause the entire reinforcing cage to float. Conventional fixing measures are unreliable and cannot fundamentally solve the floating problem, resulting in insufficient effective pile length and substandard load-bearing performance.

[0004] Meanwhile, traditional construction involves single-machine, single-pipe sequential operations, making it impossible to perform processes such as pipe sinking, grouting, and pipe pulling in parallel. This results in low equipment utilization, poor process coordination, low construction efficiency, long construction period, and high overall costs. Summary of the Invention

[0005] The purpose of this invention is to provide a method for the coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata, aiming to solve the problems of hole collapse, high friction, steel cage floating, and low efficiency in the construction of cast-in-place piles in easily collapsible strata in the prior art.

[0006] This invention provides a method for coordinated construction of casing hammer driving and vibratory pipe pulling in easily collapsible strata, comprising the following construction steps: 1) Pile location layout and pre-embedding of special pile shoes, wherein the outer diameter of the special pile shoes is larger than the outer diameter of the casing, and the inner side of the special pile shoes is provided with anti-floating components; 2) A walking pile driver with upper and lower limit clamps is used for positioning, and the single-section ultra-long integral casing is coaxially connected with the pre-embedded special pile shoe. 3) A hydraulic impact hammer is used to hammer the casing, and the upper limit clamp moves dynamically downward with the casing to control the verticality of the casing; 4) After the casing has sunk to about 2 / 3 of the design depth, the piling machine is moved and hammering continues until the casing is driven to the standard depth. 5) The steel cage is hoisted and fixed to the bottom of the steel cage by hooking and fixing it with the anti-floating component on the inside of the specially made pile shoe to prevent it from floating. 6) High-level hoisting and pouring of concrete to the designated elevation; 7) A hydraulic vibratory hammer is used to vibrate and pull out the pipe simultaneously to excite and compact the concrete to form piles; 8) The use of one machine, two pipes, and three cranes in a coordinated flow operation enables parallel and continuous construction of two pile positions with seamless connection of procedures.

[0007] Furthermore, in construction step 1), the specially made pile shoe includes a pile tip plate, several blade-reinforced ribs, and several externally reinforced ribs; the pile tip plate is a circular steel plate, the blade-reinforced ribs have a right-angled triangular structure, and the blade-reinforced ribs are radially and uniformly welded to the bottom of the pile tip plate to form a conical cross-shaped blade structure; the externally reinforced ribs are welded to the blade-reinforced ribs to form an integral rigid skeleton; The top of the pile tip plate is provided with a socket, and the bottom end of the sleeve is embedded in the socket to form a sealed connection; during the sinking of the sleeve, an annular drag-reducing gap is formed between the outer wall of the sleeve and the borehole wall.

[0008] Furthermore, the top of the pile tip plate is provided with an outer peripheral plate that circumferentially surrounds the top of the pile tip plate to form the socket. The socket is coaxially arranged with the pile tip plate, and the inner diameter of the socket matches the outer diameter of the bottom end of the sleeve. The bottom end of the sleeve is embedded in the socket to achieve a tight connection.

[0009] Furthermore, an integrated annular drag-reducing section is formed between the outer wall of the outer perimeter plate and the outer wall of the pile tip plate. The pile tip plate is welded with several upper side reinforcement ribs, which are evenly spaced along the circumference of the outer plate and aligned with the blade reinforcement ribs. The outer side wall of the upper side reinforcement ribs is flush with the outer side wall of the pile tip plate. The bottom of the upper side reinforcement ribs is welded and fixed to the drag reduction section. The upper side reinforcement ribs have a right-angled triangular structure.

[0010] Furthermore, in construction step 2), the pile driver is equipped with a fixed lower clamp and a movable upper clamp. The movable upper clamp is linked with the winch and moves down synchronously with the casing as it sinks, forming a dual-point dynamic limit with the fixed lower clamp.

[0011] Furthermore, the one-machine-two-pipe-three-crane coordinated assembly line operation is as follows: one pile driver fixes two casings in sequence, the first crane equipped with a vibratory hammer is responsible for lifting and pulling the casings, the second crane equipped with an impact hammer is responsible for hammering and sinking the casings, and the third crane is responsible for hoisting the steel cage, platform, and hopper; after the pile driver sinks the casings to 2 / 3 depth, the machine is moved, and the two pile positions form a "one pile sinking, one pile grouting" assembly line operation.

[0012] Furthermore, in construction step 1), several of the anti-floating components are arranged at intervals along the top circumference of the special pile shoe to hook and cooperate with the steel mesh at the bottom of the steel cage to prevent the steel cage from floating during pouring; the anti-floating component is a 7-shaped steel bar, and the top height of the 7-shaped steel bar is higher than the installation height of the steel mesh at the bottom of the steel cage. The 7-shaped steel bar includes a vertical fixed section and a horizontal hook section; the vertical fixed section is vertically welded to the bottom of the socket, the vertical fixed section is fixedly connected to the horizontal hook section, and the horizontal hook section is horizontally away from the center of the sleeve and bent downward to form an elastic barb structure.

[0013] Furthermore, a swing rod is hinged to the top of the vertical fixed section, and a hook head for hooking the reinforcing stirrups of the steel cage is connected to the top of the swing rod. A directional sleeve is sleeved between the vertical fixed section and the swing rod, and a return spring is connected to the bottom of the directional sleeve. The return spring is sleeved on the vertical fixed section, and a support ring is provided on the vertical fixed section. The return spring is located between the directional sleeve and the support ring. The two sides of the directional sleeve are respectively provided with elastically deformable crossbars, the rigidity of which is greater than the elasticity of the return spring; the vertical fixed section is provided with a locking ring for locking the directional sleeve, the locking ring being located above the support ring; the top of the directional sleeve is provided with a semi-circular guide strip, the semi-circular guide strip being attached to one side of the swing rod. During the lowering of the steel cage, after the steel mesh of the steel cage passes over the elastic barb, the steel mesh moves the horizontal bar by pressing down, thereby causing the directional sleeve to separate from the swing rod until the directional sleeve is engaged with the locking ring. The semi-circular guide strip restricts the tilting direction of the swing rod, so that the swing rod drives the barb to hook the stiffening stirrup.

[0014] Furthermore, the swing rod is provided with a limiting ring for restricting the upward movement of the beam sleeve. The beam sleeve has an annular groove adapted to the locking ring inside. The semi-circular guide strip passes through the limiting ring and is exposed above the limiting ring. The limiting ring has an inwardly recessed opening groove for the semi-circular guide strip to pass through. The inner sidewall of the semi-circular guide strip is provided with an elastic strip for driving the swing rod to tilt.

[0015] Furthermore, the elastic strip is an arc-shaped elastic steel sheet. One end of the arc-shaped elastic steel sheet is fixedly connected to the inner wall of the semi-circular guide strip, and the other end of the arc-shaped elastic steel sheet extends obliquely toward the swing rod and elastically abuts against the side wall of the swing rod. The bending direction of the arc-shaped elastic steel sheet is consistent with the tilting direction of the swing rod, providing a directional elastic driving force for the swing rod.

[0016] Compared with existing technologies, the present invention provides a method for the coordinated construction of casing hammering and vibratory pipe pulling for pile formation in easily collapsible strata. It employs a specially designed pile shoe with an outer diameter larger than the casing, forming a ring-shaped friction-reducing gap during casing driving, significantly reducing the outer wall friction of the casing. This method is suitable for easily collapsible strata such as deep fill and loose sand. The specially designed pile shoe incorporates anti-floating components to prevent the reinforcing cage from floating during concrete pouring, thus improving pile quality. The single-section ultra-long casing reduces joints, improving pile verticality and continuity. Dynamic upper and lower clamps provide precise control of the casing's verticality, preventing casing deviation. After the casing reaches 2 / 3 of its depth, the machine is moved to continue driving, allowing for parallel casing driving and grouting processes, improving construction efficiency. High-level hoisting and high-level concrete pouring, combined with vibratory pipe pulling for compaction, ensure uniform and dense concrete in the pile body, preventing diameter reduction and pile breakage. The coordinated operation of one machine, two pipes, and three hoists enables parallel construction at two pile locations with seamless process connections, significantly improving construction efficiency and reducing equipment and labor costs. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the construction process of the collaborative construction method for casing hammering and vibration extraction pile forming in easily collapsible strata provided by the present invention. Figure 2 This is a structural schematic diagram of the collaborative construction method for casing hammering and vibration extraction pile forming in easily collapsible strata provided by the present invention. Figure 3 This is a three-dimensional schematic diagram of the steel cage and special pile shoe provided by the present invention; Figure 4 This is a three-dimensional schematic diagram of the specially designed pile boot provided by the present invention; Figure 5 This is a bottom view structural diagram of the specially designed pile boot provided by the present invention; Figure 6 This is a cross-sectional structural diagram of the specially designed pile shoe and casing provided by the present invention; Figure 7 This is a three-dimensional schematic diagram of the upper side reinforcing rib plate and the special pile shoe provided by the present invention; Figure 8 This is a structural schematic diagram of the anti-floating component provided by the present invention.

[0018] In the diagram: 10. Sleeve 20. Special pile shoe 30. Anti-floating component 30. Reinforcing cage 40. Pile driver 50. Hydraulic impact hammer 60. Pile tip plate 21. Blade-reinforced rib plate 22. External reinforcing rib plate 23. Outer plate 24. Socket 25. Upper side reinforcing rib plate 26. Vertical fixing section 31. Horizontal hook section 32. Swing rod 33. Backhook head 34. Tension sleeve 35. Return spring 36. Support ring 37. Horizontal bar 38. Locking ring 39. Semicircular guide strip 310. Limiting ring 311. Annular groove 312. Elastic strip 313. Reinforcing mesh 41. Stiffening stirrup 42. Fixed lower clamp 51. Movable upper clamp 52. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0021] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0022] Reference Figure 1-8 The image shown is a preferred embodiment of the present invention.

[0023] The construction method for combined hammer driving and vibratory pipe pulling for pile foundation formation in easily collapsible strata includes the following steps: 1) Pile location layout and pre-embedding of special pile shoe 20. The outer diameter of special pile shoe 20 is larger than the outer diameter of casing 10. Anti-floating component 30 is provided on the inner side of special pile shoe 20. 2) The walking pile driver 50 with upper and lower limit clamps is positioned to coaxially connect the single-section ultra-long integral casing 10 with the pre-embedded special pile shoe 20. 3) A 60mm hydraulic impact hammer is used to drive the tube into the ground. The upper limit clamp moves dynamically downward with the tube to limit its position and control the verticality of the casing by 10mm. 4) After the casing 10 is driven to about 2 / 3 of the design depth, the pile driver 50 is moved and the hammer is continued to drive the casing to the standard for stopping the hammer. 5) The steel cage 40 is hoisted to a high position and fixed to prevent floating by hooking the anti-floating component 30 on the inside of the special pile shoe 20 to the steel mesh 41 at the bottom of the steel cage 40. 6) High-level hoisting and pouring of concrete to the designated elevation; 7) A hydraulic vibratory hammer is used to vibrate and pull out the pipe simultaneously to excite and compact the concrete to form piles; 8) The use of one machine, two pipes, and three cranes in a coordinated flow operation enables parallel and continuous construction of two pile positions with seamless connection of procedures.

[0024] The aforementioned method for combined hammer-driven drag-reducing casing 10 and vibratory pipe extraction for pile formation in easily collapsible strata utilizes a specially designed pile shoe 20 with an outer diameter larger than that of the casing 10. This creates a ring-shaped drag-reducing gap during casing driving, significantly reducing the outer wall friction of the casing 10 and making it suitable for easily collapsible strata such as deep fill and loose sand. The specially designed pile shoe 20 incorporates an anti-floating component 30, preventing the reinforcing cage 40 from floating during concrete pouring and improving pile quality. The single-section ultra-long casing 10 reduces joints and improves pile verticality. Continuity; dynamic limiting of upper and lower clamps to precisely control the verticality of the pipe sinking and prevent pipe deviation; after the pipe sinks to 2 / 3 depth, the machine is moved to continue sinking, realizing parallel pipe sinking and grouting processes, improving construction efficiency; 5. High-level cage and high-level concrete pouring combined with vibratory pipe pulling to ensure uniform and dense concrete in the pile body, without diameter reduction or pile breakage; one machine, two pipes, and three cranes work together in a continuous flow operation to realize parallel construction of two pile positions and seamless connection of processes, significantly improving construction efficiency and reducing equipment and labor costs.

[0025] The 50-ton walking pile driver, equipped with clamps, is easy to position and flexible to move, making it suitable for multi-pile construction.

[0026] As an extended embodiment, in construction step 1), the specially made pile shoe 20 includes a pile tip plate 21, several blade-reinforced ribs 22, and several externally reinforced ribs 23; the pile tip plate 21 is a circular steel plate, the blade-reinforced ribs 22 have a right-angled triangular structure, and the blade-reinforced ribs 22 are radially and uniformly welded to the bottom of the pile tip plate 21 to form a conical cross-shaped blade structure; the externally reinforced ribs 23 are welded to the blade-reinforced ribs 22 to form an integral rigid skeleton; The top of the pile tip plate 21 is provided with a socket 25, and the bottom end of the sleeve 10 is embedded in the socket 25 to form a sealed connection; during the sinking of the pipe, an annular drag-reducing gap is formed between the outer wall of the sleeve 10 and the borehole wall.

[0027] The tapered, cross-shaped blade structure has low soil penetration resistance and strong guidance, making it easy to penetrate loose soil layers and reduce the number of hammer blows required for pipe driving; multiple external reinforcing ribs 23 form an overall rigid skeleton, and the specially made pile shoe 20 has high strength, impact resistance, and is not easily deformed or damaged, making it suitable for long-distance hammer driving of pipes; The socket 25 is sealed to the sleeve 10 to prevent mud and sand from flowing into the pipe, ensuring the cleanliness of the pipe and facilitating the placement of the reinforcing cage 40 and concrete pouring; it automatically forms an annular friction reduction gap to continuously reduce the friction of the sinking pipe and avoid problems such as the sleeve 10 getting stuck or difficult to sink.

[0028] As an extended embodiment, the top of the pile tip plate 21 is provided with an outer plate 24 protruding upward. The outer plate 24 surrounds the top of the pile tip plate 21 to form a socket 25. The socket 25 is coaxially arranged with the pile tip plate 21. The inner diameter of the socket 25 matches the outer diameter of the bottom end of the sleeve 10. The bottom end of the sleeve 10 is embedded in the socket 25 to achieve a tight connection.

[0029] The top outer perimeter plate 24 of the pile tip plate 21 forms a coaxial bearing socket 25, ensuring the concentricity of the sleeve 10 and the special pile shoe 20 and avoiding the sleeve 10 from tilting or shifting due to eccentric force; the inner diameter of the socket 25 matches the outer diameter of the bottom end of the sleeve 10, achieving precise and tight connection, further improving the sealing effect and preventing soil and mud leakage; the structural design of the protruding outer perimeter plate 24 simplifies the connection and installation process, eliminates the need for complex positioning components, and improves on-site assembly efficiency.

[0030] As an extended embodiment, an integrated annular drag-reducing section is formed between the outer wall of the outer perimeter plate 24 and the outer wall of the pile tip plate 21. Several upper side reinforcement ribs 26 are welded onto the pile tip plate 21. The upper side reinforcement ribs 26 are evenly spaced along the circumference of the outer plate 24 and aligned vertically with the blade reinforcement ribs 22. The outer side wall of the upper side reinforcement ribs 26 is flush with the outer side wall of the pile tip plate 21. The bottom of the upper side reinforcement ribs 26 is welded and fixed to the drag reduction section. The upper side reinforcement ribs 26 have a right-angled triangular structure.

[0031] The integrated annular drag-reducing section continues the hole-enlarging effect of the specially made pile shoe 20, ensuring a uniform gap between the outer wall of the casing 10 and the hole wall, and stabilizing the drag-reducing performance; the upper side rib plate 26 and the blade-reinforced rib plate 22 are aligned vertically to form a rigid support structure that runs vertically through the hole, improving the top of the specially made pile shoe 20's resistance to compression and deformation; the outer side wall of the upper side rib plate 26 is flush with the pile tip plate 21 to avoid scraping the hole wall soil and prevent soil detachment and collapse, while not increasing the resistance of the driven pipe; the right-angled triangular upper side rib plate 26 is firmly welded, taking into account both structural strength and material economy, and reducing processing difficulty.

[0032] As an extended embodiment, in construction step 2), the pile driver 50 is equipped with a fixed lower clamp 51 and a movable upper clamp 52. The movable upper clamp 52 is linked with the winch and moves down synchronously with the casing 10 as it sinks, forming a dual-point dynamic limit with the fixed lower clamp 51.

[0033] The fixed lower clamp 51 and the movable upper clamp 52 provide dual-point dynamic limiting, constraining the verticality of the casing 10 throughout the entire process, resulting in high deviation control accuracy. The movable upper clamp 52 moves synchronously with the winch as the casing sinks, eliminating the need for repeated manual adjustments, thus achieving a high degree of automation and convenient construction. The synergistic effect of the two clamps effectively suppresses the swinging, bending, and tilting of the ultra-long casing 10, meeting the requirements for high-precision pile foundation construction.

[0034] As an extended embodiment, the one-machine-two-pipe-three-crane coordinated assembly line operation is as follows: one pile driver 50 fixes two casings 10 in sequence, the first crane equipped with a vibratory hammer is responsible for lifting and pulling the casings, the second crane equipped with an impact hammer is responsible for hammering and sinking the casings, and the third crane is responsible for hoisting the steel cage 40, platform, and hopper; after the pile driver 50 sinks the casings to 2 / 3 depth, it moves the machine away, and the two pile positions form a "one pile sinking, one pile grouting" assembly line operation.

[0035] With one machine carrying two pipes and three cranes, the division of labor is clear, maximizing equipment utilization and reducing idle waiting time; the "one pile driving pipe, one pile grouting" assembly line operation ensures uninterrupted and non-interfering processes, resulting in a stable construction rhythm; compared with traditional multi-machine operation, it requires less equipment investment, occupies less space, and has lower costs, making it suitable for construction in confined spaces.

[0036] As an extended embodiment, in construction step 1), several anti-floating components 30 are arranged at intervals along the top circumference of the special pile shoe 20 to hook and cooperate with the steel mesh 41 at the bottom of the steel cage 40 to prevent the steel cage 40 from floating during pouring; the anti-floating component 30 is a 7-shaped steel bar, and the top height of the 7-shaped steel bar is higher than the installation height of the steel mesh 41 at the bottom of the steel cage 40. The 7-shaped steel bar includes a vertical fixed section 31 and a horizontal hook section 32. The vertical fixed section 31 is vertically welded to the bottom of the socket 25. The vertical fixed section 31 and the horizontal hook section 32 are fixedly connected. The horizontal hook section 32 is horizontally away from the center of the sleeve 10 and bends downward to form an elastic barb structure.

[0037] The 7-shaped elastic barb is easy to install and reliable in hooking. It automatically locks in place when the rebar cage 40 is lowered, without the need for additional fixing. Multiple sets of anti-floating components 30 are evenly arranged around the circumference, ensuring balanced force and comprehensively suppressing the overall floating of the rebar cage 40. The horizontal hook section 32 bends upward to form an elastic barb, allowing the rebar cage 40 to be lowered smoothly. It automatically locks in place, providing a stable fixing effect. It is directly welded to the bottom of the socket 25, ensuring a firm connection that does not fall off or fail, and has high reliability.

[0038] As an extended embodiment, a swing rod 33 is hinged to the top of the vertical fixing section 31. A hook head 34 for hooking the reinforcing stirrups 42 of the steel cage 40 is connected to the top of the swing rod 33. A directional sleeve 35 is sleeved between the vertical fixing section 31 and the swing rod 33. A return spring 36 is connected to the bottom of the directional sleeve 35. The return spring 36 is sleeved on the vertical fixing section 31. A support ring 37 is provided on the vertical fixing section 31. The return spring 36 is located between the directional sleeve 35 and the support ring 37. The hook head 34 is arranged in the same direction as the transverse hook section 32. The two sides of the directional sleeve 35 are respectively provided with elastically deformable crossbars 38, the rigidity of the crossbars 38 is greater than the elasticity of the return spring 36; the vertical fixed section 31 is provided with a locking ring 39 for locking the directional sleeve 35, the locking ring 39 is located above the support ring 37; the top of the directional sleeve 35 is provided with a semi-circular guide strip 310, which is attached to one side of the swing rod 33. During the lowering of the steel cage 40, after the steel mesh 41 of the steel cage 40 passes over the elastic barb head 34, the steel mesh 41 moves the horizontal bar 38 by pressing down, thereby causing the directional sleeve 35 to separate from the swing rod 33 until the directional sleeve 35 is engaged with the locking ring 39. The semi-circular guide strip 310 restricts the tilting direction of the swing rod 33, so that the swing rod 33 drives the barb head 34 to hook the stiffening stirrup 42.

[0039] The hinged swing rod 33, paired with the barbed head 34, can hook the reinforcing cage 40 and stiffening stirrups 42 a second time, forming a double anti-floating effect of "reinforcing mesh 41 and stiffening stirrups 42", greatly improving the anti-detachment effect. The directional sleeve 35, return spring 36, and locking ring 39 work together to achieve automatic unlocking after the reinforcing cage 40 is lowered into place and automatic tilting and hooking of the swing rod 33, without manual operation, suitable for underwater and deep hole construction scenarios. The semi-circular guide strip 310 precisely restricts the tilting direction of the swing rod 33, preventing the barbed head 34 from deviating during hooking and ensuring the hooking success rate. The rigidity of the crossbar 38 is greater than the elasticity of the return spring 36, ensuring that the reinforcing mesh 41 can reliably drive the directional sleeve 35 to move onto the locking ring 39 and lock it, with stable and uninterrupted operation. The support ring 37 provides stable support for the return spring 36.

[0040] As an extended embodiment, the swing rod 33 is provided with a limiting ring 311 for limiting the upward movement of the directional sleeve 35. The directional sleeve 35 has an annular groove 312 adapted to the locking ring 39. The semi-circular guide strip 310 passes through the limiting ring 311 and is exposed above the limiting ring 311. The limiting ring 311 has an inwardly recessed opening groove for the semi-circular guide strip 310 to pass through. The inner sidewall of the semi-circular guide strip 310 is provided with an elastic strip 313 for driving the swing rod 33 to tilt.

[0041] The limiting ring 311 restricts the upward movement of the bundle sleeve 35, preventing excessive movement of the sleeve from damaging the component and extending the service life of the structure. The annular groove 312 is adapted to the locking ring 39 to achieve precise locking of the bundle sleeve 35 and prevent the sleeve from failing to reset during pouring. The semi-circular guide strip 310 passes through the opening groove of the limiting ring 311, ensuring the guiding function and avoiding interference with the limiting ring 311, thus optimizing the structural fit accuracy. The inner elastic strip 313 of the semi-circular guide strip 310 provides directional elastic driving force for the swing rod 33, ensuring that the swing rod 33 tilts and hooks quickly and stably, further improving the reliability of the anti-floating action.

[0042] As an extended embodiment, the elastic strip 313 is an arc-shaped elastic steel sheet. One end of the arc-shaped elastic steel sheet is fixedly connected to the inner side wall of the semi-circular guide strip 310, and the other end of the arc-shaped elastic steel sheet extends obliquely toward the swing rod 33 and elastically abuts against the side wall of the swing rod 33. The bending direction of the arc-shaped elastic steel sheet is consistent with the tilting direction of the swing rod 33, providing directional elastic driving force for the swing rod 33.

[0043] The directional elastic drive swing rod 33 ensures that the hook head 34 accurately hooks the stiffening stirrup 42; it provides continuous elasticity, so that the swing rod 33 automatically and quickly tilts down, and the hooking is reliable and does not jam; the arc-shaped structure buffers the collision and protects the components from deformation and damage.

[0044] The specially designed pile shoe 20 is made of Q355B steel, with a 30mm thick pile tip plate 21 as the base plate. The diameter of the base plate is 50mm larger than the outer diameter of the casing 10. Eight 25mm thick blade-reinforced ribs 22 are welded to its bottom to form a conical "X"-shaped blade structure. This structure has a small tip action surface and stress concentration, which can significantly enhance the penetration ability of dense soil or gravel layers. The blade-reinforced ribs 22 are further welded into a rigid frame by eight 18mm thick external ribs. This not only provides sufficient strength support for the pile shoe and guides the casing 10 to sink vertically to prevent pile head damage or pile tilting, but also disperses soil compression pressure through structural form, reduces disturbance to the surrounding soil, and ensures the stability of the pipe sinking operation.

[0045] Construction process flow Construction preparation 1. Collect design and survey reports, measurement control points, and geological data near the pile locations to be constructed.

[0046] 2. Provide detailed technical instructions to construction personnel to ensure that everyone understands the construction process, key points of operation, and safety precautions.

[0047] 3. Use an excavator to level the site, remove underground obstacles, and properly treat and compact loose soil that is not conducive to the operation of the walking pile driver 50.

[0048] Stake location measurement and setting out 1. Check the design drawings and confirm the coordinates and elevation of the pile locations.

[0049] 2. Use an RTK measuring instrument to measure and mark the pile positions, and draw out the center benchmark of the pile position.

[0050] 20 specially made pile shoes were pre-embedded at the pile location. 1. Weld three 7-shaped steel bars inside the special pile shoe 20, align the tip of the special pile shoe 20 with the center base point of the pile position, so that the center of the special pile shoe 20 coincides with the center of the pile position, and the special pile shoe 20 is aligned with the pile position.

[0051] 2. After the specially made pile shoe 20 is aligned with the center of the pile position, an excavator is used to backfill and compact the pile symmetrically to assist in its installation. After installation, the center point of the specially made pile shoe 20 is checked again using RTK.

[0052] 3. After completing the installation of the special pile shoe 20 at the current pile location, proceed to the next pile location for measurement and layout, and install the special pile shoe 20.

[0053] Walking double-limit hoop pile driver 50 in place 1. The JB120B walking pile driver 50 with double clamps is used to fix and limit the casing 10. The pile driver 50 is 26m high, the maximum driving depth is 45m, and the overall size is 13.7m×9m. The pile driver 50 chassis is equipped with longitudinal and transverse walking tracks, and wide steel plates are added to the bottom of both longitudinal and transverse walking tracks. The machine has good stability and low grounding pressure ratio.

[0054] 2. The entire machine is controlled by the hydraulic system to move the tracks to the pile position. After the pile driver 50 reaches the pile position, it is finely adjusted using precision instruments such as a laser rangefinder to ensure that the center line of the pile driver 50 clamp is completely aligned with the pile position, and the pile driver 50 is in place.

[0055] Fabrication of 10 extra-long single-section integral sleeve 1. The full sleeve 10 is made up of multiple short sleeves 10 with an inner diameter of 700mm and a wall thickness of 50mm. Workers use roller frames to connect adjacent short sleeves 10 to ensure that each section of short sleeve 10 is coaxial in height and that the short sleeves 10 are connected on the roller frames.

[0056] 2. The connection of sleeve 10 adopts a V-groove full welding connection, and the sections are connected one by one to form a single integral sleeve 10 with a total length of 41.3m and high coaxiality. The first crane and vibratory hammer lift the sleeve 10 to the pile driver 50 and fix it. 1. After the pile driver 50 is in place, the first crane of the SCC3200 crawler crane is connected to the SV325-6 hydraulic vibratory hammer. The SCC3200 has a maximum main boom length of 86m, a maximum lifting capacity of 320t, and a maximum lifting torque of 1820t·m; the SV325-6 hydraulic vibratory hammer has a maximum excitation force of 235t and a maximum pile extraction force of 164 tons. The first crane and the vibratory hammer are sufficient to successfully pull out the single-section ultra-long integral casing 10 from the deep soil layer. The first crane is connected to the vibratory hammer.

[0057] 2. After the vibratory hammer and the crane are connected, the vibratory hammer is used to clamp the sleeve 10. The first crane, in conjunction with the auxiliary vibratory hammer, lifts the sleeve 10 to the pile driver 50. The first crane and the vibratory hammer lift the sleeve 10.

[0058] 3. After the casing 10 is hoisted to the position of the pile driver 50, the upper and lower clamps of the pile driver 50 are closed, and the clamp bolts are tightened to close the clamps, thus fixing the casing 10. The upper clamp is then moved up to limit the movement of the casing 10.

[0059] 4. After the sleeve 10 is fixed with clamps, plumb lines are suspended in two directions to observe the verticality of the sleeve 10. The hydraulic system of the pile driver 50 is used to fine-tune the pile driver 50 to ensure that the center of the sleeve 10 and the special pile shoe 20 are on the same vertical line. After the adjustment is completed, the first crane and vibratory hammer slowly lower the sleeve 10 and vertically insert it into the pre-embedded special pile shoe 20 to complete the docking of the sleeve 10 and the special pile shoe 20.

[0060] 5. After the first crane and vibratory hammer have completed the installation of the casing 10 at the current pile position, they will move to the next pile position to wait for the assembly line operation.

[0061] The second crane and impact hammer used to lift and sink the 10-meter drag-reducing casing. 1. After the casing 10 is connected to the special pile shoe 20, the second crane is used to lift the HHP16 hydraulic impact hammer 60. The crane model is QUY260, with a maximum main boom length of 83m, a maximum lifting capacity of 260t, and a maximum lifting torque of 1500t·m. The impact hammer core weighs 16t, has a maximum stroke of 1.5m, and a maximum impact energy of 240kN·m, which is sufficient to successfully sink the single section of the casing 10 to the design elevation.

[0062] 2. After the second crane lifts the HHP16 hydraulic impact hammer 60 to the top of the pile sleeve 10, adjust the hammer cap of the hydraulic impact hammer 60 to align with the top of the sleeve 10, and slowly lower it. The hammer body is fixed to the top of the sleeve 10 by the hammer cap, and its weight is completely supported by the sleeve 10.

[0063] 3. After the impact hammer is in place, the simple support for recording the penetration is placed against the side of the casing 10 to facilitate subsequent observation of the penetration of the submerged tube. During observation, the crossbar 38 of the support is used as a reference. After each set of hammers (10 hammers per set), a reference line is drawn on the casing 10 with chalk. The penetration of each set is obtained by measuring the distance between each reference line.

[0064] 4. After the impact hammer is in place, start the hydraulic impact hammer 60. When starting to hit, control the hammer core to lightly strike the sleeve 10 with a small stroke. After the hammer is raised and the pile is stabilized, adjust the stroke to 0.75m for normal hitting. The stroke can be adjusted by the stroke adjustment knob and the engine speed.

[0065] 5. During the hammering and sinking process, a dedicated person observes the verticality of the casing 10 in two directions to monitor its verticality. If any deviation is found, it is corrected in time. At the same time, as the casing 10 sinks, the upper clamp on the pile driver 50 moves down synchronously. The distance between the upper clamp and the top of the casing 10 is maintained at about 4m. Together with the lower clamp, the upper clamp fixes the pipe pile and limits its position, ensuring that the verticality of the sinking pipe meets the requirements.

[0066] After casing 10 is driven to 2 / 3 of the designed underground depth, pile driver 50 is moved. 1. The hydraulic impact hammer 60 repeatedly hammers the casing. When the casing 10 is 2 / 3 of the way down below the ground, the casing tends to be stable. At this time, the pile driver 50 clamp is loosened to release the restriction on the casing 10 so that the impact hammer can further sink the casing 10 into place.

[0067] 2. After the clamp is deployed, the pile driver 50 is moved to the next pile position for continuous operation; after the pile driver 50 is moved to the next pile position and in place, the first crane and vibratory hammer lift another sleeve 10 to the pile driver 50 for fixing, positioning and connecting the special pile shoe 20.

[0068] The second crane and impact hammer continued to hammer the casing for 10 seconds until the hammer was removed from the standard position. 1. After the pile driver 50 is moved, the second crane and the impact hammer continue to impact the casing 10 until the casing 10 reaches the hammer removal standard.

[0069] 2. The standard for stopping the hammer is controlled by the design bearing layer of the pile end and the penetration of the last three sets of hammers determined by the test pile. The penetration of each set of ten hammers shall not exceed 10cm, and the penetration value of each set of ten hammers shall not increase.

[0070] 3. After the hammer is withdrawn, the second crane lifts the impact hammer away from the casing 10 that has been sunk to the current pile position and moves to the next pile position for continuous operation; after the pile driver 50 and casing 10 are in place at the next pile position, the hammering of the casing begins.

[0071] The third crane lifts the high-level working platform to the top of casing 10. 1. The third crane is a crawler crane of model QUY260, with a maximum main boom length of 76m, a maximum lifting capacity of 135t, and a maximum lifting torque of 720t·m. The third crane lifts the high-level working platform to the top of the casing 10 for workers to safely complete the extension operation of the rebar cage 40.

[0072] 2. If the top of the casing 10 is high above the ground, in order to ensure the safety of the workers climbing at height, the workers should enter the platform in advance and be lifted to the top of the casing 10 together with the platform.

[0073] Fabrication of anti-floating steel cage 40 1. The steel cage 40 is prefabricated at the steel processing plant. Due to the excessive length of the cast-in-place pile, the steel cage 40 is extended section by section at the sleeve 10 opening to prevent the steel cage 40 from deforming due to excessive length.

[0074] 2. The standard section of the reinforcing cage 40 is 12m long and 600mm in diameter. The bottom of the first section of the reinforcing cage 40 is welded with a reinforcing mesh 41, which is linked with the 7-shaped reinforcing bars welded to the special pile shoe 20. When the reinforcing cage 40 is lowered to the bottom of the hole, the 7-shaped reinforcing bars in the special pile shoe 20 hook onto the reinforcing mesh 41 at the bottom of the reinforcing cage 40, forming an anti-floating cage measure.

[0075] The third crane lowers the steel cage section by section into the pipe and extends it. 1. The third crane is used to lift the steel cage 40. The steel cage 40 is lifted from multiple points, and U-shaped reinforcing bars are set at the lifting points. The steel cage 40 is placed into the sleeve 10 section by section. When lowering, it is aligned with the center of the sleeve 10. The operators assist in adjusting the steel cage 40 to enter the sleeve 10 to avoid collision with the pipe wall.

[0076] 2. When the top of the rebar cage 40 is about 1m above the top of the sleeve 10, a horizontal steel pipe is passed through the rebar cage 40 and placed on the top of the sleeve 10 to fix the rebar cage 40.

[0077] 3. Workers extend the 40mm rebar cage on a high-level work platform. When extending the 40mm rebar cage, the upper and lower sections of the 40mm rebar cage are on the same vertical line, and the main reinforcement is spliced ​​using single-sided lap welding.

[0078] 4. After the steel cage 40 is fully extended, replace the anti-disengagement hook of the crane with an open hook so that the steel cage 40 can be fully lowered into the sleeve 10 and then automatically disengage.

[0079] 5. Using an open hook, the entire steel cage 40 is completely lowered into the sleeve 10. The operators assist in directing the crane to lift and adjust the steel cage 40, and check whether the special pile shoe 207-shaped steel bars are firmly connected to the steel mesh 41 at the bottom of the steel cage 40. After the steel cage 40 is lowered into place, the open hook is released, and the anti-disengagement hook is replaced. The third crane then smoothly lowers the operators and the high-level work platform back to the ground.

[0080] The third crane lifts the hopper to pour concrete into the pipe up to the pile top elevation. 1. Concrete is filled using a hopper; a disc-shaped cover plate with a diameter larger than the discharge port is installed inside the hopper. The cover plate is connected to a cable, and the opening and closing of the hopper discharge port can be controlled by raising and lowering the cover plate through the cable.

[0081] 2. Place the hopper into a shallow pit about 1m deep, so that the top of the hopper is level with the ground to facilitate loading. When the concrete mixer truck loads the hopper, block the outlet with the cover plate.

[0082] 3. When the concrete loading is completed, the main hook of the third crane lifts the hopper, and the auxiliary hook connects to the cover plate through the cable. The hopper is then lifted and placed above the casing 10 and aligned with the center of the casing 10. After the hopper is stable, the lower discharge port is embedded into the casing 10. At this time, the auxiliary hook is pulled to open the hopper cover plate, so that the concrete can be directly poured into the casing 10 through the discharge port, thus realizing high-level concrete pouring.

[0083] 4. After all the concrete in the hopper has been unloaded, use crane #3 to lift the hopper back to the concrete transport truck for reloading and pouring. Repeat this process until the concrete level in casing 10 reaches the design elevation.

[0084] 5. After the third crane completes the grouting operation, it is moved to the next pile location for continuous operation.

[0085] The first crane and vibratory hammer were used to vibrate and pull out the pipe for pile driving. 1. After the concrete pouring is completed, the first crane lifts the vibratory hammer to the top of the sleeve 10 and clamps the sleeve 10.

[0086] 2. Start the vibratory hammer and vibrate for 5-10 seconds before starting to pull out the pipe while vibrating. Stop pulling out the pipe every 0.5-1.0m and continue vibrating for 5-10 seconds to fully vibrate the concrete inside the pipe before pulling it out further. Repeat this operation until the entire casing 10 is pulled out.

[0087] 3. After the casing 10 is pulled out, check the pile head diameter, the concrete elevation at the top of the pile, and whether the reinforcing cage 40 has floated. If it has floated, cut it off.

[0088] 4. After the pipe is pulled out, the first crane is connected to a vibratory hammer to hold the casing 10 and move it to the next pile position for continuous operation.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata, characterized in that, The construction steps include the following: 1) Pile location layout and pre-embedding of special pile shoes, wherein the outer diameter of the special pile shoes is larger than the outer diameter of the casing, and the inner side of the special pile shoes is provided with anti-floating components; 2) A walking pile driver with upper and lower limit clamps is used for positioning, and the single-section ultra-long integral casing is coaxially connected with the pre-embedded special pile shoe. 3) A hydraulic impact hammer is used to hammer the casing, and the upper limit clamp moves dynamically downward with the casing to control the verticality of the casing; 4) After the casing has sunk to about 2 / 3 of the design depth, the piling machine is moved and hammering continues until the casing is driven to the standard depth. 5) The steel cage is hoisted and fixed to the bottom of the steel cage by hooking and fixing it with the anti-floating component on the inside of the specially made pile shoe to prevent it from floating. 6) High-level hoisting and pouring of concrete to the designated elevation; 7) A hydraulic vibratory hammer is used to vibrate and pull out the pipe simultaneously to excite and compact the concrete to form piles; 8) The use of one machine, two pipes, and three cranes in a coordinated flow operation enables parallel and continuous construction of two pile positions with seamless connection of procedures.

2. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 1, characterized in that, In construction step 1), the specially made pile shoe includes a pile tip plate, several blade-reinforced ribs, and several externally reinforced ribs; the pile tip plate is a circular steel plate, and the blade-reinforced ribs are radially and uniformly welded to the bottom of the pile tip plate to form a conical cross-shaped blade structure; the externally reinforced ribs are welded to the blade-reinforced ribs to form an integral rigid skeleton. The top of the pile tip plate is provided with a socket, and the bottom end of the sleeve is embedded in the socket to form a sealed connection; during the sinking of the sleeve, an annular drag-reducing gap is formed between the outer wall of the sleeve and the borehole wall.

3. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 2, characterized in that... The top of the pile tip plate has an outer peripheral plate protruding upwards. The outer peripheral plate surrounds the top of the pile tip plate to form the socket. The socket is arranged coaxially with the pile tip plate. The inner diameter of the socket matches the outer diameter of the bottom end of the sleeve.

4. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 3, characterized in that, An integrated annular drag-reducing section is formed between the outer wall of the outer perimeter plate and the outer wall of the pile tip plate. The pile tip plate is welded with several upper side reinforcement ribs, which are evenly spaced along the circumference of the outer plate and aligned with the blade reinforcement ribs. The outer side wall of the upper side reinforcement ribs is flush with the outer side wall of the pile tip plate, and the bottom of the upper side reinforcement ribs is welded and fixed to the drag reduction section.

5. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 1, characterized in that, In construction step 2), the pile driver is equipped with a fixed lower clamp and a movable upper clamp. The movable upper clamp is linked with the winch and moves down synchronously with the casing as it sinks, forming a dual-point dynamic limit with the fixed lower clamp.

6. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 1, characterized in that, The one-machine-two-pipe-three-crane coordinated assembly line operation is as follows: one pile driver fixes two casings in sequence, the first crane equipped with a vibratory hammer is responsible for lifting and pulling the casings, the second crane equipped with an impact hammer is responsible for hammering and sinking the casings, and the third crane is responsible for hoisting the steel cage, platform, and hopper; after the pile driver sinks the casings to 2 / 3 depth, the machine is moved, and the two pile positions form a "one pile sinking, one pile grouting" assembly line operation.

7. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in any one of claims 1 to 6, characterized in that, In construction step 1), several of the anti-floating components are arranged at intervals along the top circumference of the special pile shoe, and are used to hook and cooperate with the steel mesh at the bottom of the steel cage to prevent the steel cage from floating during the pouring process; the anti-floating component is a 7-shaped steel bar, and the top height of the 7-shaped steel bar is higher than the installation height of the steel mesh at the bottom of the steel cage. The 7-shaped steel bar includes a vertical fixed section and a horizontal hook section; the vertical fixed section is vertically welded to the bottom of the socket, the vertical fixed section is fixedly connected to the horizontal hook section, and the horizontal hook section is horizontally away from the center of the sleeve and bent downward to form an elastic barb structure.

8. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 7, characterized in that, The top of the vertical fixed section is hinged to a swing rod, and the top of the swing rod is connected to a hook head for hooking the reinforcing stirrups of the steel cage. A directional sleeve is sleeved between the vertical fixed section and the swing rod. A return spring is connected to the bottom of the directional sleeve. The return spring is sleeved on the vertical fixed section. A support ring is provided on the vertical fixed section. The return spring is located between the directional sleeve and the support ring. The two sides of the directional sleeve are respectively provided with elastically deformable crossbars, the rigidity of which is greater than the elasticity of the return spring; the vertical fixed section is provided with a locking ring for locking the directional sleeve, the locking ring being located above the support ring; the top of the directional sleeve is provided with a semi-circular guide strip, the semi-circular guide strip being attached to one side of the swing rod. During the lowering of the steel cage, after the steel mesh of the steel cage passes over the elastic barb, the steel mesh moves the horizontal bar by pressing down, thereby causing the directional sleeve to separate from the swing rod until the directional sleeve is engaged with the locking ring. The semi-circular guide strip restricts the tilting direction of the swing rod, so that the swing rod drives the barb to hook the stiffening stirrup.

9. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 8, characterized in that, The swing rod is provided with a limiting ring for restricting the upward movement of the beam sleeve. The beam sleeve has an annular groove that matches the locking ring. The semi-circular guide strip passes through the limiting ring and is exposed above the limiting ring. The limiting ring has an inwardly recessed opening groove for the semi-circular guide strip to pass through. The inner sidewall of the semi-circular guide strip is provided with an elastic strip for driving the swing rod to tilt.

10. The method for coordinated construction of casing hammer driving and vibratory pipe pulling for pile forming in easily collapsible strata as described in claim 9, characterized in that... The elastic strip is an arc-shaped elastic steel sheet. One end of the arc-shaped elastic steel sheet is fixedly connected to the inner wall of the semi-circular guide strip, and the other end of the arc-shaped elastic steel sheet extends obliquely toward the swing rod and elastically abuts against the side wall of the swing rod. The bending direction of the arc-shaped elastic steel sheet is consistent with the tilting direction of the swing rod, providing directional elastic driving force for the swing rod.

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