A steel pipe pile driving device

Abstract

The present invention provides a steel pipe pile driving device, comprising: a pile cap for being arranged at the top end of the steel pipe pile; a support cylinder, the bottom end of which is arranged on the pile cap; a pile hammer sleeved outside the support cylinder; a lifting mechanism connected to the pile hammer for driving the pile hammer to move along the support cylinder; a slewing mechanism arranged on the pile hammer and the pile cap for enabling the pile hammer to vertically impact the pile cap downward, or for enabling the pile hammer to rotate relative to the pile cap and impact the pile cap. The present invention can solve the problem that the pile cannot be driven into the designed depth due to reasons such as soil plug and hard strata during the pile driving process, and causes less damage to the soil layers around and at the end of the pile, less loss of the bearing capacity of the pile, reduces the number of equipment hoisting times, greatly expands the applicable site of the steel pipe pile, reduces energy consumption, and significantly improves the construction efficiency and safety.

Description

Technical Field

[0001] The present invention belongs to the technical field of pile foundation construction, and particularly relates to a steel pipe pile driving device. Background Art

[0002] During the process of driving an open-ended steel pipe pile into the soil layer, a large amount of soil rushes into the pipe to form a soil plug. The correct judgment of the influence of the soil plug on the drivability of the pile is related to the pile design, the selection of construction equipment, and the construction efficiency. A large number of experimental and on-site measurement data at home and abroad show that the height and degree of occlusion of the soil plug in the open-ended steel pipe pile vary with many factors such as soil properties, pile geometric characteristics, pile driving methods, pile penetration depth, and the depth of entering the bearing layer, among which the relationship with the soil layer properties and pile diameter is the most significant. In soft soil areas, the height of the soil plug in large-diameter steel pipe piles is almost equal to the penetration depth, or even higher than the mud surface, showing non-occlusion or incomplete occlusion. By pre-conducting the drivability analysis of dynamic pile driving, a pile driving device with a higher adaptability to the pile and soil layer can be selected to smoothly drive the pile to the designed depth and meet the bearing capacity requirements. However, due to the complexity of the problem, the risk of hammer refusal often occurs during pile driving construction in areas or soil layers lacking experience, which will cause the following adverse results or choices:

[0003] (1) The selected hammer type is not large enough to drive the pile to the designed elevation, and the bearing capacity required by the design cannot be achieved. The pile spacing has to be reduced, sacrificing the economic span of the superstructure.

[0004] (2) Change to a larger hammer type and forcefully hammer, which not only increases the investment but also may cause pile body damage due to forceful hammering.

[0005] (3) Change to a larger hammer type and increase the pile wall thickness at the same time. The pile wall thickness far exceeds the thickness required to meet the design bearing capacity, resulting in material waste.

[0006] (4) Forced to change the design to other pile types such as cast-in-place piles, greatly increasing the project cost and construction period.

[0007] (5) Remove the soil under the pile tip by drilling a small hole or lowering a flushing device through the pile used as a casing. Due to the unpredictability of the result, this method is generally avoided.

[0008] (6) Use methods such as water flushing method, air-lift method, pre-drilling method, etc. to remove the soil plug in the pile. This is one of the current feasible directions, but during the implementation process, the operation is cumbersome and the work efficiency is not high. Summary of the Invention

[0009] The object of the present invention is to provide a steel pipe pile driving device, which can solve the problem that the pile cannot be driven into the designed depth due to reasons such as soil plugging and hard strata during the pile driving process, and cause less damage to the soil layers around and at the end of the pile, with less loss of pile bearing capacity, and reduce the number of equipment hoisting times, greatly expanding the applicable site of the steel pipe pile, reducing energy consumption, and significantly improving construction efficiency and safety.

[0010] The present invention is achieved through the following technical solutions:

[0011] A steel pipe pile driving device, comprising:

[0012] A pile cap for being arranged at the top end of the steel pipe pile;

[0013] A support cylinder, the bottom end of which is arranged on the pile cap;

[0014] A pile hammer, which is sleeved outside the support cylinder;

[0015] A lifting mechanism, which is connected to the pile hammer and used to drive the pile hammer to move along the support cylinder;

[0016] A slewing mechanism, which is arranged on the pile hammer and the pile cap and used to make the pile hammer vertically impact the pile cap downward, or used to make the pile hammer rotate relative to the pile cap and impact the pile cap.

[0017] Furthermore, it further includes a hole-leading mechanism for leading holes. The hole-leading mechanism is detachably arranged at the top end of the support cylinder. The support cylinder is a hollow cylinder, and a through hole communicating with the support cylinder is opened on the pile cap.

[0018] Furthermore, the slewing mechanism includes a plurality of first impact keys and a plurality of second impact keys. The plurality of first impact keys are arranged at equal intervals along the circumferential direction of the support cylinder at the top end of the pile cap. A first inclined surface is arranged on one side of the first impact key in the first direction, and a gap for inserting the second impact key is formed between two adjacent first impact keys;

[0019] The number of the plurality of second impact keys is the same as that of the plurality of first impact keys. The plurality of second impact keys are arranged at equal intervals along the circumferential direction of the support cylinder at the bottom end of the pile hammer. A second inclined surface is arranged on one side of the second impact key in the second direction, and the second direction is opposite to the first direction;

[0020] A first annular chute is arranged at the top end of the pile hammer, and one end of the lifting mechanism is slidably arranged in the first annular chute.

[0021] Furthermore, a plurality of alignment limiting grooves are formed along the circumferential direction at the lower part of the outer side wall of the support cylinder. The number of the plurality of alignment limiting grooves is equal to and corresponds to that of the plurality of second impact keys one by one. One end of the second impact key is slidably arranged in the corresponding alignment limiting groove;

[0022] The steering limit groove includes a first vertical side wall, a top wall, a second vertical side wall, an inclined side wall, and a third vertical side wall that are connected in sequence. The distance between the second vertical side wall and the first vertical side wall is less than the distance between the third vertical side wall and the first vertical side wall.

[0023] A plurality of second impact keys correspond to a plurality of first impact keys one by one. When the second impact key contacts the third vertical side wall, the second impact key is located above the gap on the first direction side of the corresponding first impact key.

[0024] When the second impact key contacts the second vertical side wall, the bottom end of the second inclined surface of the second impact key is located above the top end of the first inclined surface of the corresponding first impact key.

[0025] Further, the lifting mechanism includes a plurality of double-acting cylinders. The top end of the double-acting cylinder is connected to the top end of the support cylinder, and its bottom end is slidably arranged in the first annular chute through the hammer core hanger foot.

[0026] Further, an annular suspension beam is provided at the top end of the support cylinder. A second annular chute is provided at the bottom end of the annular suspension beam. The top end of the double-acting cylinder is slidably arranged in the second annular chute through the cylinder hanger foot.

[0027] Further, the lifting mechanism further includes a number of cylinder limit rings. The number of cylinder limit rings is sleeved on the outer side of the support cylinder and is arranged at intervals. A number of positioning holes for a plurality of double-acting cylinders to pass through are provided on the cylinder limit rings.

[0028] Further, a number of lifting lugs are symmetrically provided at the top end of the annular suspension beam.

[0029] Further, the pile cap includes an inner holding cylinder, an outer holding cylinder, a bearing plate beam, and a number of force transmission bolts. The inner holding cylinder is arranged at the bottom end of the bearing plate beam. The outer holding cylinder is sleeved on the outer side of the inner holding cylinder and is arranged at the bottom end of the bearing plate beam. An insertion groove for the top end of the steel pipe pile to be inserted is formed between the outer holding cylinder, the inner holding cylinder, and the bearing plate beam. A number of force transmission bolts are arranged at intervals along the circumferential direction of the insertion groove in the insertion groove. One end of the force transmission bolt is connected to the inner holding cylinder, and the other end is connected to the outer holding cylinder. The top end of the bearing plate beam is connected to the bottom end of the support cylinder.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows: integrating vertical impact and rotary impact into one, two modes such as impact or impact plus rotation can be adopted, which can give full play to the advantages of various method principles, increase the ability of steel pipe piles to penetrate various soil layers, and effectively solve the problem that the pile cannot be driven into the design depth due to reasons such as soil plugging and hard strata during the pile driving process, greatly expanding the types of soil layers where steel pipe piles can be applied; there is no need for repeated hoisting operations, which can greatly improve the construction efficiency, save construction period, materials and personnel allocation when constructing in difficult-to-drive soil layers; it causes less damage to the soil layers around and at the end of the pile, and the bearing capacity loss of the pile is small, greatly expanding the applicable sites of steel pipe piles, creating conditions for reducing the use of cast-in-place piles in relevant soil layers, and can significantly save energy and reduce emissions, reduce energy consumption, and significantly improve construction efficiency and safety; the structural layout is reasonable, the pile hammer is sleeved outside the support cylinder, and it has a larger moment of inertia around the cross-section center than a solid hammer of the same weight, and the generated rotary impact effect is more obvious, with high safety and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic structural diagram of the steel pipe pile driving device of the present invention;

[0032] Figure 2 is a cross-sectional view of the steel pipe pile driving device of the present invention;

[0033] Figure 3 is Figure 1 an enlarged schematic view of part A of

[0034] Figure 4 is a schematic position diagram of the first impact key and the second impact key during impact when the steel pipe pile driving device of the present invention is in the impact plus rotation mode;

[0035] Figure 5 is a schematic position diagram of the first impact key and the second impact key when the impact of the steel pipe pile driving device of the present invention ends;

[0036] Figure 6 is a schematic structural diagram of the upper part of the steel pipe pile driving device of the present invention;

[0037] Figure 7 is a schematic diagram of the pile cap of the steel pipe pile driving device of the present invention sleeved on the steel pipe pile;

[0038] Figure 8 is a schematic structural diagram of the lower part of the outer side wall of the support cylinder of the steel pipe pile driving device of the present invention.

[0039] In the figure, 1 - pile cap, 11 - inner holding cylinder, 12 - outer holding cylinder, 13 - bearing plate beam, 14 - force - transmitting bolt, 15 - through - hole, 2 - support cylinder, 21 - alignment limiting groove, 211 - first vertical side wall, 212 - top wall, 213 - second vertical side wall, 214 - inclined side wall, 215 - third vertical side wall, 22 - annular lifting beam, 221 - lifting lug, 3 - pile hammer, 31 - first annular sliding groove, 4 - lifting mechanism, 41 - two - way oil cylinder, 42 - hammer core hanger foot, 43 - oil cylinder hanger foot, 44 - oil cylinder limiting ring, 5 - slewing mechanism, 51 - first impact key, 511 - first inclined surface, 52 - second impact key, 521 - second inclined surface, 6 - hole - guiding mechanism, 7 - steel pipe pile, 8 - soil plug. Detailed implementation manners

[0040] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used for differential description and cannot be understood as indicating or implying relative importance.

[0043] It should be noted that in this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0044] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the inventive product is customarily placed during use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0045] Please refer to Figure 1 and Figure 2 , Figure 1 , which is a schematic structural diagram of the steel pipe pile driving device of the present invention, Figure 2 , which is a cross-sectional view of the steel pipe pile driving device of the present invention. A steel pipe pile driving device includes a pile cap 1, a support cylinder 2, a pile hammer 3, a lifting mechanism 4 and a slewing mechanism 5. The pile cap 1 is used to be arranged at the top end of the steel pipe pile 7. The bottom end of the support cylinder 2 is arranged on the pile cap 1. The pile hammer 3 is sleeved outside the support cylinder 2. The lifting mechanism 4 is connected to the pile hammer 3 and is used to drive the pile hammer 3 to move along the support cylinder 2. The slewing mechanism 5 is arranged on the pile hammer 3 and the pile cap 1 and is used to make the pile hammer 3 vertically impact the pile cap 1 downward, or to make the pile hammer 3 rotate relative to the pile cap 1 and impact the pile cap 1.

[0046] When the steel pipe pile sinking device of the present invention is actually used, first lift the steel pipe pile 7, position it by means of a guide frame or other appropriate means, and complete the processes of pile insertion, pile stabilization, etc. through equipment such as a vibratory hammer. After the steel pipe pile 7 is stably inserted, lift the steel pipe pile sinking device of the present invention to the top of the steel pipe pile 7 by a crane, and make the pile cap 1 sleeved on the top of the steel pipe pile 7. Turn on the impact mode, the lifting mechanism 4 lifts the pile hammer 3 along the support cylinder 2 to a preset height, and then controls the pile hammer 3 to freely fall and impact the pile cap 1. Under the action of the slewing mechanism 5, the pile hammer 3 only generates a downward impact force. The steel pipe pile 7 is subjected to the impact force and generates an axial displacement, causing the steel pipe pile 7 to sink. In the impact mode, control the pile hammer 3 to repeatedly impact the pile cap 1, accumulate the axial displacement of the steel pipe pile 7, and gradually increase the penetration depth of the steel pipe pile 7 until the pile sinking is completed. If it is difficult for the steel pipe pile 7 to penetrate or there is a situation of hammer refusal during the pile sinking process, then turn on the impact plus slewing mode. When the pile hammer 3 freely falls and impacts the pile cap 1, under the action of the slewing mechanism 5, the pile hammer 3 rotates relative to the pile cap 1 and impacts the pile cap 1. According to the mechanical principle, the impact force of the pile hammer 3 on the pile cap 1 is decomposed into a tangential force around the center of the circle of the steel pipe pile 7 and an axial force along the axis of the steel pipe pile 7. The steel pipe pile 7 is subjected to the impact and torsion, generating a circumferential displacement and an axial displacement, causing the steel pipe pile 7 to rotate and sink. In the impact plus slewing mode, control the pile hammer 3 to repeatedly impact the pile cap 1, accumulate the circumferential displacement and axial displacement of the steel pipe pile 7, and gradually increase the penetration depth of the steel pipe pile 7 until the pile sinking is completed.

[0047] Among them, a through hole penetrating the top and bottom of the pile hammer 3 is provided inside the pile hammer 3, and its three-dimensional structure is a cylindrical hollow structure. The pile hammer 3 is sleeved on the outside of the support cylinder 2 through the through hole on it and can move along the length direction of the support cylinder 2. The cylindrical pile hammer 3 has a larger moment of inertia around the cross-section center than a solid hammer of the same weight, and the impact and slewing effect on the steel pipe pile 7 is more obvious, with high safety and reliability.

[0048] In one embodiment, the steel pipe pile driving device of the present invention further includes a hole-leading mechanism 6 for leading holes. The hole-leading mechanism 6 is detachably arranged at the top end of the support cylinder 2. The support cylinder 2 is a hollow cylinder, and a through hole 15 communicating with the support cylinder 2 is provided on the pile cap 1. By adding the hole-leading mechanism 6 and integrating the hole-leading method into the steel pipe pile driving device of the present invention, the steel pipe pile driving device of the present invention adopts an impact plus rotation plus hole-leading mode. Adding the hole-leading method can further solve the problem that the steel pipe pile 7 cannot be driven into the designed depth due to reasons such as soil plugs 8 and hard strata during the pile driving process. The hole-leading method can adopt methods such as air-lift hole-leading, flushing hole-leading, and drilling hole-leading. The hole-leading mechanism 6 can adopt corresponding existing equipment according to the different hole-leading methods used. The hollow interior of the support cylinder 2 and the through hole 15 on the pile cap 1 can be used for the hole-leading tool of the hole-leading mechanism 6 to be lowered to the surface of the soil plug 8 in the steel pipe pile 7. The hole-leading tools include, for example, a flushing nozzle and a high-pressure pipe, an air-lift drill bit and a drill pipe, etc. The inner diameter of the support cylinder 2 is the same as the diameter of the through hole 15, and the support cylinder 2 is welded and fixed to the pile cap 1. Specifically, the hole-leading mechanism 6 of the air-lift hole-leading method mainly includes a main machine, a hydraulic power unit, an air compressor unit, a water pump unit, and a drilling tool. The models of the main machine and the hydraulic power unit are selected depending on the geological conditions and the required maximum hole-leading depth. The model of the air compressor unit is adapted according to the air-lift cycle working pressure and the air supply volume. The drilling tool is used as the hole-leading tool and includes a drag bit and a roller bit. The former is suitable for geological conditions such as sandy soil, clay, gravel, and strongly weathered soft rock, and the latter is suitable for medium-hard rock such as strongly weathered and weakly weathered rock. The working principle of air-lift hole-leading is to send compressed air along the air delivery pipeline of the double-wall drilling tool into the wellbore to a certain depth, inject it into the wellbore through a mixer and mix it with the circulating liquid. Since the density of the mixed liquid is less than the density of the flushing liquid, a pressure difference is generated between the wellbore and the slurry discharge pipe, and under the action of the wellbore liquid column pressure, the gas-liquid mixture in the slurry discharge pipe flows upward at a higher speed, so as to continuously discharge the core or cuttings at the bottom of the hole to the surface. The gas, liquid, and solid phases brought up flow through the reverse circulation vibrating screen and are discharged into the sedimentation tank. The precipitated slurry then flows back into the hole to supplement the space of the circulating liquid, and continuously circulates to form a continuous drilling process in this way. The hole-leading mechanism 6 of the flushing hole-leading method mainly includes a water pump, a water delivery pipeline, a water injection pipe, etc. The water injection pipe is used as the hole-leading tool. The flushing hole-leading method uses high-pressure water flow passing through the water injection pipe attached to the side of the pile or inside the hollow pile to loosen the soil layer near the side or tip of the pile, facilitating hammering. The hole-leading mechanism 6 of the drilling hole-leading method can be a submersible drilling rig or a rotary drilling rig. The submersible drilling rig transmits the power from the submersible motor to the output shaft through a speed reducer to drive the drill bit to cut the rock and soil. During operation, the power device dives into the bottom of the hole to directly drive the drill bit to rotate and cut, and the drill pipe only rotates to play a role in connecting and transmitting torque and conveying slurry. The rotary drilling rig is driven by the power device to rotate the rotary device of the drilling rig, thereby driving the drill pipe with the drill bit to rotate, and the drill bit cuts the soil.

[0049] Please refer to Figure 3 , Figure 4 andFigure 5 , Figure 3 is Figure 1 an enlarged schematic view of part A of Figure 4 a schematic view of the positions of the first impact key and the second impact key during impact when the steel pipe pile driving device of the present invention is in the impact plus rotation mode, Figure 5This is a schematic diagram of the positions of the first impact key and the second impact key when the impact of the steel pipe pile driving device of the present invention ends. In one embodiment, the slewing mechanism 5 includes a plurality of first impact keys 51 and a plurality of second impact keys 52. The plurality of first impact keys 51 are arranged at equal intervals in the circumferential direction of the support cylinder 2 at the top end of the pile cap 1. A first inclined surface 511 is provided on one side of the first impact key 51 in the first direction, and a gap for inserting the second impact key 52 is formed between two adjacent first impact keys 51; the number of the plurality of second impact keys 52 is the same as the number of the plurality of first impact keys 51. The plurality of second impact keys 52 are arranged at equal intervals in the circumferential direction of the support cylinder 2 at the bottom end of the pile hammer 3. A second inclined surface 521 is provided on one side of the second impact key 52 in the second direction, and the second direction is opposite to the first direction; a first annular chute 31 is provided at the top end of the pile hammer 3, and one end of the lifting mechanism 4 is slidably arranged in the first annular chute 31. Since the number of the plurality of first impact keys 51 is the same as the number of the plurality of second impact keys 52, the number of the plurality of gaps formed by the plurality of first impact keys 51 is also the same as the number of the plurality of second impact keys 52. After the pile hammer 3 impacts the pile cap 1, the plurality of second impact keys 52 are respectively located in the plurality of gaps. The vertical cross-sections of the first impact key 51 and the second impact key 52 are trapezoidal, and the projections of the first impact key 51 and the second impact key 52 are fan-shaped. Therefore, in the impact mode, the lifting mechanism 4 drives the pile hammer 3 to be vertically lifted along the support cylinder 2 to a preset height, and then controls the pile hammer 3 to freely fall, so that the second impact key 52 on the pile hammer 3 falls vertically back into the gap. At this time, the pile hammer 3 only generates a downward impact force on the pile cap 1, and the steel pipe pile 7 is subjected to the impact force and generates an axial displacement; while in the impact plus slewing mode, the lifting mechanism 4 drives the pile hammer 3 to be vertically lifted along the support cylinder 2 to a preset height, and then controls the pile hammer 3 to rotate a certain angle relative to the pile cap 1, so that the bottom end of the second inclined surface 521 of the second impact key 52 is located above the top end of the first inclined surface 511 of the first impact key 51, and then makes the pile hammer 3 freely fall until the bottom end of the second inclined surface 521 of the second impact key 52 impacts the top end of the first inclined surface 511 of the first impact key 51. Under the cooperation of the second inclined surface 521 of the second impact key 52 and the first inclined surface 511 of the first impact key 51, the second inclined surface 521 of the second impact key 52 moves along the first inclined surface 511 of the first impact key 51, thereby causing the pile hammer 3 to rotate relative to the pile cap 1 and impact the pile cap 1. According to the mechanical principle, at this time, the impact force of the pile hammer 3 on the pile cap 1 is decomposed into a tangential force around the center of the steel pipe pile 7 and an axial force along the axis of the steel pipe pile 7, and the steel pipe pile 7 is subjected to the impact and torsion effects and generates a circumferential displacement and an axial displacement. Among them, the first direction can be the counterclockwise direction, and the second direction can be the clockwise direction. The number of the first impact keys 51 and the second impact keys 52 can be determined according to actual needs. Preferably, the number of both the first impact keys 51 and the second impact keys 52 is eight.

[0050] Please refer to Figure 8 ,Figure 8This is a schematic structural view of the lower part of the outer sidewall of the support cylinder in the steel pipe pile driving device of the present invention. In an embodiment, a plurality of alignment limiting grooves 21 are provided along the circumferential direction of the lower part of the outer sidewall of the support cylinder 2. The number of the plurality of alignment limiting grooves 21 is equal to and corresponds one by one to the number of the plurality of second impact keys 52. One end of the second impact key 52 is slidably arranged in the corresponding alignment limiting groove 21. The alignment limiting groove 21 includes a first vertical sidewall 211, a top wall 212, a second vertical sidewall 213, an inclined sidewall 214 and a third vertical sidewall 215 which are connected in sequence. The distance between the second vertical sidewall 213 and the first vertical sidewall 211 is less than the distance between the third vertical sidewall 215 and the first vertical sidewall 211. The plurality of second impact keys 52 correspond one by one to the plurality of first impact keys 51. When the second impact key 52 contacts the third vertical sidewall 215, the second impact key 52 is located above the gap on one side of the corresponding first impact key 51 in the first direction. When the second impact key 52 contacts the second vertical sidewall 213, the bottom end of the second inclined surface 521 of the second impact key 52 is located above the top end of the first inclined surface 511 of the corresponding first impact key 51. To facilitate controlling the rotation of the pile hammer 3 by a certain angle and realizing the switching between the impact mode and the impact plus rotation mode, a plurality of alignment limiting grooves 21 are provided on the outer sidewall of the support cylinder 2. The third vertical sidewall 215 of the alignment limiting groove 21 and one side of a first impact key 51 away from its first inclined surface 511 are in the same plane. Therefore, after the pile hammer 3 impacts the pile cap 1, the plurality of second impact keys 52 are respectively located in the plurality of gaps, and the second impact key 52 contacts the third vertical sidewall 215 of the corresponding alignment limiting groove 21.Therefore, when the impact mode is required, the lifting mechanism 4 drives the pile hammer 3 to move upward, so that the second impact key 52 is lifted along the corresponding third vertical side wall 215 to the top of the third vertical side wall 215. At this time, the second impact key 52 is located above the gap on one side of the first impact key 51 in the first direction. Then, the pile hammer 3 is controlled to fall freely, so that the second impact key 52 falls vertically back into the corresponding gap. At this time, the pile hammer 3 only generates a downward impact force on the pile cap 1, and the steel pipe pile 7 is subjected to the impact and generates an axial displacement. When the impact plus rotation mode is required, the lifting mechanism 4 drives the pile hammer 3 to move upward, so that the second impact key 52 moves along the corresponding third vertical side wall 215 to the top of the third vertical side wall 215. Then, the lifting mechanism 4 continues to drive the pile hammer 3 to move upward, so that the second impact key 52 contacts the inclined side wall 214 and moves along the inclined side wall 214 to contact the second vertical side wall 213, so that the pile hammer 3 rotates relative to the pile cap 1 by a certain angle. At this time, the bottom end of the second inclined surface 521 of the second impact key 52 is located above the top end of the first inclined surface 511 of the first impact key 51. According to the required hammering energy, it can be selected whether to continue to drive the pile hammer 3 to move upward by the lifting mechanism 4. After the second impact key 52 is lifted along the second vertical side wall 213 to a predetermined height, the pile hammer 3 is controlled to fall freely until the bottom end of the second inclined surface 521 of the second impact key 52 impacts the top end of the first inclined surface 511 of the first impact key 51. Under the cooperation of the second inclined surface 521 of the second impact key 52 and the first inclined surface 511 of the first impact key 51, the second inclined surface 521 of the second impact key 52 moves along the first inclined surface 511 of the first impact key 51, so that the pile hammer 3 rotates relative to the pile cap 1 and impacts the pile cap 1. According to the mechanical principle, the impact force of the pile hammer 3 on the pile cap 1 is decomposed into a tangential force around the center of the steel pipe pile 7 and an axial force along the axis of the steel pipe pile 7. Therefore, by designing the steering limit groove 21 on the support cylinder 2 and the distance that the lifting mechanism 4 drives the pile hammer 3 to move upward, the impact mode and the impact plus rotation mode are switched. Preferably, the inclined side wall 214 and the second vertical side wall 213 and the third vertical side wall 215 are all transitioned by arcs. It is convenient for the second impact key 52 to move smoothly along the third vertical side wall 215, the inclined side wall 214 and the second vertical side wall 213.

[0051] Please refer to Figure 6 , Figure 6This is a schematic structural diagram of the upper part of the steel pipe pile driving device of the present invention. In one embodiment, the lifting mechanism 4 includes a plurality of double-acting cylinders 41. The top end of the double-acting cylinder 41 is connected to the top end of the support cylinder 2, and its bottom end is slidably arranged in the first annular chute 31 through the hammer core hanger 42. The double-acting cylinder 41 can be filled with oil or return oil in both directions, that is, the piston rod of the double-acting cylinder 41 can provide an upward lifting force and a downward thrust to the pile hammer 3. That is, the pile hammer 3 can freely fall to impact the pile cap 1, or the pile hammer 3 can be pushed downward by the double-acting cylinder 41 while freely falling to impact the pile cap 1, so as to adjust the falling speed of the pile hammer 3 and the impact force of the pile hammer 3 on the pile cap 1, and can greatly adjust the impact and rotational force on the pile cap 1, thereby adjusting the impact and rotational force on the steel pipe pile 7. The first annular chute 31 is an inverted T-shaped groove, and the hammer core hanger 42 is an inverted T-shaped structure matching the first annular chute 31. The hammer core hanger 42 is slidably arranged in the first annular chute 31, and the piston rod of the double-acting cylinder 41 is connected to the hammer core hanger 42 to enable the pile hammer 3 to rotate relative to the pile cap 1 when the pile hammer 3 is lifted and lowered.

[0052] In one embodiment, an annular lifting beam 22 is provided at the top end of the support cylinder 2, and a second annular chute is provided at the bottom end of the annular lifting beam 22. The top end of the double-acting cylinder 41 is slidably arranged in the second annular chute through the cylinder hanger 43. This device is convenient for installing the double-acting cylinder 41, making the double-acting cylinder 41 form an integral structure with the support cylinder 2, which is convenient for hoisting. The second annular chute is a T-shaped structure, and the cylinder hanger 43 is a T-shaped structure matching the second annular chute. The double-acting cylinder 41 is slidably arranged in the second annular chute through the cylinder hanger 43, so that the double-acting cylinder 41 is hoisted on the annular lifting beam 22 and forms an integral with the support cylinder 2. The inner diameter of the annular lifting beam 22 is the same as the outer diameter of the support cylinder 2 and is connected by welding. If a hole guiding mechanism 6 is provided, the hole guiding mechanism 6 can be placed on the top surface of the annular lifting beam 22. In one embodiment, a plurality of lifting lugs 221 are symmetrically provided at the top end of the annular lifting beam 22. It is convenient for the crane to lift the steel pipe pile driving device of the present invention through the lifting lugs 221.

[0053] In one embodiment, the lifting mechanism 4 further includes a plurality of cylinder limiting rings 44. The plurality of cylinder limiting rings 44 are sleeved outside the support cylinder 2 and are arranged at intervals. A plurality of positioning holes for respectively passing through a plurality of double-acting cylinders 41 are provided on the cylinder limiting rings 44. The plurality of cylinder limiting rings 44 are arranged at intervals along the length direction of the support cylinder 2. Each double-acting cylinder 41 sequentially passes through the positioning holes of the plurality of cylinder limiting rings 44. The double-acting cylinder 41 is fixed by the plurality of cylinder limiting rings 44 to maintain a vertical setting, and the cylinder limiting rings 44 fix the plurality of double-acting cylinders 41 into a cylindrical shape. The plurality of double-acting cylinders 41 can rotate integrally around the support cylinder 2 to ensure that during the pile driving process, the high-pressure oil pipes of the double-acting cylinders 41 always face the direction of the high-pressure power station that provides oil pressure for the double-acting cylinders 41. Preferably, the number of the cylinder limiting rings 44 can be set to 2 to 4.

[0054] Please refer to Figure 7 , Figure 7 which is a schematic diagram of the pile cap of the steel pipe pile driving device of the present invention sleeved on the steel pipe pile. In one embodiment, the pile cap 1 includes an inner holding cylinder 11, an outer holding cylinder 12, a bearing disc beam 13 and a plurality of force transmission bolts 14. The inner holding cylinder 11 is arranged at the bottom end of the bearing disc beam 13. The outer holding cylinder 12 is sleeved outside the inner holding cylinder 11 and is arranged at the bottom end of the bearing disc beam 13. An insertion groove for the top end of the steel pipe pile 7 to be inserted is formed between the outer holding cylinder 12, the inner holding cylinder 11 and the bearing disc beam 13. A plurality of force transmission bolts 14 are arranged at intervals along the circumference of the insertion groove in the insertion groove. One end of the force transmission bolt 14 is connected to the inner holding cylinder 11, and the other end thereof is connected to the outer holding cylinder 12. The top end of the bearing disc beam 13 is connected to the bottom end of the support cylinder 2. The first impact key 51 is fixed to the top end of the bearing disc beam 13. During actual use, a rotary limit groove for placing a plurality of force transmission bolts 14 is opened at the top end of the steel pipe pile 7. When the pile cap 1 is placed on the top end of the steel pipe pile 7, the inner holding cylinder 11 is located inside the steel pipe pile 7, the outer holding cylinder 12 is sleeved outside the steel pipe pile 7, a plurality of force transmission bolts 14 are respectively placed in the corresponding rotary limit grooves, and the bearing disc beam 13 is in contact with the top end of the steel pipe pile 7. Preferably, the outer diameter of the inner holding cylinder 11 is about 1 cm smaller than the inner diameter of the steel pipe pile 7, and the inner diameter of the outer holding cylinder 12 is about 1 cm larger than the outer diameter of the steel pipe pile 7. A plurality of circular holes are opened at the corresponding positions of the inner holding cylinder 11 and the outer holding cylinder 12. The force transmission bolts 14 pass through the corresponding circular holes of the inner holding cylinder 11 and the outer holding cylinder 12 and are welded. Through the cooperation of the force transmission bolts 14 and the rotary limit grooves, the pile cap 1 transmits the tangential force around the center of the steel pipe pile 7 to the steel pipe pile 7, causing the steel pipe pile 7 to generate circumferential displacement.

[0055] The following briefly describes the construction method of using the steel pipe pile driving device of the present invention:

[0056] Step 1, open a plurality of rotary limit grooves for placing a plurality of force transmission bolts 14 at the top end of the steel pipe pile 7;

[0057] Step 2, hoist the steel pipe pile 7, position it by appropriate means such as a guiding frame, and complete the processes of inserting and stabilizing the steel pipe pile 7 through equipment such as a vibrating hammer;

[0058] Step 3, after the steel pipe pile 7 is inserted and stabilized, hoist the steel pipe pile driving device of the present invention by a crane, sleeve the pile cap 1 on the top end of the steel pipe pile 7, and make a plurality of force transmission bolts 14 respectively placed in a plurality of rotary limit grooves. Among them, the steel pipe pile driving device of the present invention does not install the hole-leading mechanism 6;

[0059] Step 4, hoist the hole-leading mechanism 6 and firmly install the hole-leading mechanism 6 on the top surface of the annular lifting beam 22 through bolts;

[0060] Step Five: Activate the impact mode. Lift the pile hammer 3 through the bidirectional cylinder, so that the second impact key 52 on the pile hammer 3 moves along the corresponding third vertical sidewall 215 to the top of the third vertical sidewall 215. Then, control the pile hammer 3 to freely fall, so that the second impact key 52 falls vertically back into the corresponding gap. At this time, the pile hammer 3 only generates a downward impact force on the pile cap 1. The steel pipe pile 7 is subjected to the impact and generates an axial displacement, causing the steel pipe pile 7 to sink;

[0061] Step Six: Repeat Step Five, so that the pile hammer 3 repeatedly impacts the pile cap 1, resulting in multiple impact effects, accumulating the axial displacement of the steel pipe pile 7. The penetration depth of the steel pipe pile 7 gradually increases until any of the following situations occurs: pile driving is completed, it is difficult to penetrate, or hammer refusal. The situations of difficult penetration and hammer refusal are both determined by the agreed axial penetration degree. For example, if the axial penetration degree ≤ 2.5 mm / blow, it indicates that the situation of difficult penetration occurs. If the axial penetration degree ≤ 1 mm / blow, it indicates that the situation of hammer refusal occurs;

[0062] Step Seven: If the situation of difficult penetration or hammer refusal occurs, activate the impact plus rotation mode. Lift the pile hammer 3 through the bidirectional cylinder, so that the second impact key 52 on the pile hammer 3 moves along the corresponding third vertical sidewall 215 to the top of the third vertical sidewall 215. Then, continue to drive the pile hammer 3 upward through the bidirectional cylinder, so that the second impact key 52 contacts the inclined sidewall 214 and moves along the inclined sidewall 214 to contact the second vertical sidewall 213, thereby causing the pile hammer 3 to rotate a certain angle relative to the pile cap 1. At this time, the bottom end of the second inclined surface 521 of the second impact key 52 is located above the top end of the first inclined surface 511 of the first impact key 51. According to the required hammering energy, it can be selected whether to continue to drive the pile hammer 3 upward through the bidirectional cylinder. After the second impact key 52 is lifted along the second vertical sidewall 213 to a predetermined height, control the pile hammer 3 to freely fall until the bottom end of the second inclined surface 521 of the second impact key 52 impacts the top end of the first inclined surface 511 of the first impact key 51. Under the cooperation of the second inclined surface 521 of the second impact key 52 and the first inclined surface 511 of the first impact key 51, the second inclined surface 521 of the second impact key 52 moves along the first inclined surface 511 of the first impact key 51, thereby causing the pile hammer 3 to rotate relative to the pile cap 1 and impact the pile cap 1. According to the mechanical principle, at this time, the impact force of the pile hammer 3 on the pile cap 1 is decomposed into a tangential force around the center of the steel pipe pile 7 and an axial force along the axis of the steel pipe pile 7. The steel pipe pile 7 is subjected to the impact and torsion, generating a circumferential displacement and an axial displacement, causing the steel pipe pile 7 to rotate and sink;

[0063] Step Eight: Repeat Step Seven, so that the pile hammer 3 repeatedly impacts the pile cap 1, resulting in multiple impact plus rotation effects, accumulating the circumferential displacement and axial displacement of the steel pipe pile 7. The penetration depth of the steel pipe pile 7 gradually increases until any of the following situations occurs: pile driving is completed, it is difficult to penetrate, or hammer refusal;

[0064] Step 9: If it is difficult to penetrate or the hammering is refused, turn on the impact + rotation + pre-drilling mode, that is, while repeating Step 7, turn on the pre-drilling mechanism 6 to assist in pre-drilling;

[0065] Step 10: Repeat Step 9 until the pile driving is completed.

[0066] Compared with the prior art, the beneficial effects of the present invention are as follows: Integrating vertical impact and rotary impact into one, two modes of impact or impact + rotation can be adopted, which can give full play to the advantages of various method principles, increase the ability of the steel pipe pile 7 to penetrate various soil layers, and effectively solve the problem that the pile cannot be driven into the designed depth due to reasons such as soil plug 8 and hard strata during the pile driving process, greatly expanding the soil layer categories applicable to the steel pipe pile 7; There is no need for repeated hoisting operations, which can greatly improve the construction efficiency, save the construction period, materials and personnel allocation when constructing in soil layers with difficult pile driving; It causes less damage to the soil layers around and at the end of the pile, and the bearing capacity loss of the pile is small, greatly expanding the applicable sites of the steel pipe pile 7, creating conditions for reducing the use of cast-in-place piles in relevant soil layers, and can significantly save energy and reduce emissions, reduce energy consumption, and significantly improve construction efficiency and safety; The structural layout is reasonable, the pile hammer 3 is sleeved outside the support cylinder 2, and it has a larger moment of inertia around the cross-section center than a solid hammer of the same weight, and the generated rotary impact effect is more obvious, with high safety and reliability.

[0067] The above is only a preferred embodiment of the present invention, and it does not impose any form of limitation on the present invention. Therefore, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A steel pipe pile driving device, characterized in that, Comprising: A pile cap for being arranged at the top end of a steel pipe pile; A support cylinder, the bottom end of which is arranged on the pile cap; A pile hammer, which is sleeved outside the support cylinder; A lifting mechanism, which is connected with the pile hammer and is used for driving the pile hammer to move along the support cylinder; A slewing mechanism, which is arranged on the pile hammer and the pile cap and is used for enabling the pile hammer to vertically impact the pile cap downward, or for enabling the pile hammer to rotate relative to the pile cap and impact the pile cap; The slewing mechanism comprises a plurality of first impact keys and a plurality of second impact keys. The plurality of first impact keys are arranged at equal intervals along the circumferential direction of the support cylinder at the top end of the pile cap. A first inclined surface is arranged on one side of the first impact key in the first direction. A gap for inserting the second impact key is formed between two adjacent first impact keys; The number of the plurality of second impact keys is the same as that of the plurality of first impact keys. The plurality of second impact keys are arranged at equal intervals along the circumferential direction of the support cylinder at the bottom end of the pile hammer. A second inclined surface is arranged on one side of the second impact key in the second direction, and the second direction is opposite to the first direction; A first annular chute is arranged at the top end of the pile hammer. The lifting mechanism comprises a plurality of bidirectional oil cylinders. The top end of the bidirectional oil cylinder is connected with the top end of the support cylinder, and the bottom end thereof is slidably arranged in the first annular chute through a hammer core hanging foot; A plurality of steering limiting grooves are formed in the lower part of the outer side wall of the support cylinder along the circumferential direction thereof. The number of the plurality of steering limiting grooves is equal to that of the plurality of second impact keys and they are in one-to-one correspondence. One end of the second impact key is slidably arranged in the corresponding steering limiting groove; The steering limiting groove comprises a first vertical side wall, a top wall, a second vertical side wall, an inclined side wall and a third vertical side wall which are connected in sequence. The distance between the second vertical side wall and the first vertical side wall is less than the distance between the third vertical side wall and the first vertical side wall; The plurality of second impact keys and the plurality of first impact keys are in one-to-one correspondence. When the second impact key contacts the third vertical side wall, the second impact key is located above the gap on one side of the corresponding first impact key in the first direction; When the second impact key contacts the second vertical side wall, the bottom end of the second inclined surface of the second impact key is located above the top end of the first inclined surface of the corresponding first impact key.

2. The steel pipe pile driving device according to claim 1, characterized in that, It further comprises a hole-drilling mechanism for hole drilling. The hole-drilling mechanism is detachably arranged at the top end of the support cylinder. The support cylinder is a hollow cylinder, and a through hole communicated with the support cylinder is formed in the pile cap.

3. The steel pipe pile driving device according to claim 1, characterized in that, A ring-shaped hanging beam is arranged at the top end of the support cylinder. A second annular chute is arranged at the bottom end of the ring-shaped hanging beam. The top end of the bidirectional oil cylinder is slidably arranged in the second annular chute through an oil cylinder hanging foot.

4. The steel pipe pile driving device according to claim 3, characterized in that, The lifting mechanism further comprises a plurality of oil cylinder limiting rings. The plurality of oil cylinder limiting rings are sleeved outside the support cylinder and are arranged at intervals. A plurality of positioning holes for respectively allowing the plurality of bidirectional oil cylinders to pass through are formed in the oil cylinder limiting rings.

5. The steel pipe pile driving device according to claim 3, characterized in that, A plurality of lifting lugs are symmetrically arranged at the top end of the ring-shaped hanging beam.

6. The steel pipe pile driving device according to claim 1, characterized in that, The pile cap includes an inner holding cylinder, an outer holding cylinder, a bearing disc beam, and a number of force transmission bolts. The inner holding cylinder is arranged at the bottom end of the bearing disc beam. The outer holding cylinder is sleeved outside the inner holding cylinder and is arranged at the bottom end of the bearing disc beam. An insertion groove for the top end of the steel pipe pile to insert is formed among the outer holding cylinder, the inner holding cylinder, and the bearing disc beam. A number of the force transmission bolts are arranged at intervals along the circumferential direction of the insertion groove in the insertion groove. One end of the force transmission bolt is connected to the inner holding cylinder, and the other end thereof is connected to the outer holding cylinder. The top end of the bearing disc beam is connected to the bottom end of the support cylinder.

Images