阅读说明：本技术 一种用于地基基础加固的注浆螺旋钢桩及其植桩方法 (Grouting spiral steel pile for foundation stabilization and pile planting method thereof ) 是由 王欣华 周玉明 康和勇 刘月辉 胡博 李国宝 任永结 房立兴 李玉龙 于 2020-08-21 设计创作，主要内容包括：本发明公开了一种用于地基基础加固的注浆螺旋钢桩,包括桩杆,桩杆为钢管,桩杆的顶部设有第一接口,第一接口通过连接结构与旋转驱动设备的动力输出端相连,桩杆的底部为桩尖,桩杆的外回转表面上设有螺旋叶片,桩尖处设有多个与桩杆贯通的出浆孔；旋转驱动设备的动力输出端连接至注浆管。本发明中,还可以在的桩杆内设有内置注浆管,完成全部螺旋钢桩的连接、旋入和注浆,当水泥浆液从桩孔壁返至地面时停止注浆,松脱旋转驱动设备与最上一节钢桩的连接,使用锁具锁住内置注浆管,提升旋转驱动设备拔出所有的内置注浆管,并拆解内置注浆管清洗后以备重复使用。植桩中减小桩体旋压入土的阻力,提高了螺旋钢桩的承载力。(The invention discloses a grouting spiral steel pile for foundation stabilization, which comprises a pile rod, wherein the pile rod is a steel pipe, the top of the pile rod is provided with a first interface, the first interface is connected with a power output end of rotary driving equipment through a connecting structure, the bottom of the pile rod is a pile tip, the outer rotary surface of the pile rod is provided with a spiral blade, and the pile tip is provided with a plurality of slurry outlet holes communicated with the pile rod; the power output end of the rotary driving device is connected to the grouting pipe. In the invention, built-in grouting pipes can be arranged in the pile rod to complete the connection, screw-in and grouting of all spiral steel piles, the grouting is stopped when cement grout returns to the ground from the wall of the pile hole, the connection between the rotary driving device and the uppermost section of steel pile is loosened, the built-in grouting pipes are locked by using a lock, the rotary driving device is lifted to pull out all the built-in grouting pipes, and the built-in grouting pipes are disassembled and cleaned for reuse. The resistance of the pile body in the process of pile planting in the spinning process is reduced, and the bearing capacity of the spiral steel pile is improved.)

1. The utility model provides a slip casting spiral steel pile for foundation stabilization, includes stake pole (5), stake pole (5) are the steel pipe, the top of stake pole (5) is equipped with first interface (3), first interface (3) link to each other with the power take off end of rotary driving equipment (2) through connection structure, the bottom of stake pole (5) is stake point (7), be equipped with helical blade (4), its characterized in that on the outer revolution surface of stake pole (5):

a plurality of grout outlet holes (6) communicated with the pile rod (5) are formed in the pile tip (7); the power output end of the rotary driving device (2) is connected to the grouting pipe (1).

2. The grouting spiral steel pile according to claim 1, characterized by further comprising N sections of steel pile extension sections, each section of steel pile extension section comprises an extension section pile rod (51) and a spiral blade (4) arranged on the outer rotating surface of the pile rod (5), and both ends of each section of steel pile extension section are in threaded connection with the connected steel pile extension section or spiral steel pile.

3. A method of placing a grouted spiral steel pile, the pile placing equipment comprising a drilling machine with a rotary driving device (2) and a grouting pump, characterized in that the step of placing the grouted spiral steel pile according to claim 1 is:

step one, adjusting a drilling angle after the drilling machine with the rotary driving equipment (2) is in place; aligning the pile tip of the spiral steel pile to a design position, connecting the top of the pile rod of the spiral steel pile with the power output end of the rotary driving device (2), and mixing cement slurry according to the cement mixing amount and the water cement ratio required by the design; determining the drilling speed of the spiral steel pile and the grouting flow rate of the grouting pump;

step two, starting a grouting pump to enable cement slurry to be sequentially conveyed to a pile tip (7) at the bottom of the pile rod along a grouting pipe (1) connected with the grouting pump and an inner cavity of the pile rod, and enabling the cement slurry to flow out of a slurry outlet hole (6); at the moment, the rotary driving device (2) is started to enable the spiral steel pile to rotate and drill at a set drilling speed, the spiral blade (4) is screwed into the soil, cement slurry is continuously injected at a set grouting flow rate while screwing in, the grouting pressure is gradually and stably increased, and the grouting pump is stopped when the top of the spiral steel pile is drilled to be close to the ground along with the drilling; controlling the rotary driving equipment (2) to rotate reversely, and loosening the connection between the rotary driving equipment (2) and the top of the spiral steel pile; the rotary driving device (2) and the output end are lifted upwards by a certain height;

step three, taking a section of the steel pile extension section in the spiral steel pile according to claim 2, firmly connecting the bottom end of the pile rod of the section of the steel pile extension section with the top end of the previous section of the pile rod, and connecting the power output end of the rotary driving device (2) with the top end of the pile rod of the section of the steel pile extension section; returning to the step two, completing the connection, the screwing-in and the grouting of all the spiral steel piles;

step four, continuing to keep grouting, stopping grouting by a grouting pump when cement grout returns to the ground from the pile hole wall, controlling the rotary driving equipment (2) to rotate reversely, and loosening the connection between the power output end of the rotary driving equipment (2) and the top of the spiral steel pile;

and fifthly, putting graded gravel and cement slurry in the inner cavity of the pile rod into the pile rod, tamping to form concrete so as to improve the vertical compression resistance of the pile rod, completing the construction of one spiral steel pile, removing the equipment, and performing the pile planting construction of the next spiral steel pile.

4. The grouting spiral steel pile according to claim 1, characterized in that a built-in grouting pipe (10) is arranged in the pile rod (5), the first connector (3) of the pile rod (5) is provided with internal threads, and the upper end of the built-in grouting pipe (10) is provided with external threads; the output end of the rotary driving device (2) is fixed with the upper end of a conversion joint (12), and the lower end of the conversion joint (12) is simultaneously connected with the built-in grouting pipe (10) and the first interface (3) of the pile rod (5); the bottom of the built-in grouting pipe (10) is positioned above the pile tip (7), a grout stop plug (9) is arranged between the outer revolution surface of the bottom end of the built-in grouting pipe (10) and the inner revolution surface of the pile rod (5), and all grout outlets (6) are positioned below the grout stop plug (9);

and a support ring (11) is arranged between the upper end of the pile rod (5) and the upper end of the built-in grouting pipe (10), and the support ring (11) and the grout stop plug (9) are used for keeping the built-in grouting pipe (10) coaxial with the pile rod (5).

5. The grouting spiral steel pile according to claim 4, characterized by further comprising N sections of steel pile extension sections, wherein each section of steel pile extension section comprises an extension section pile rod (51) and an extension section built-in grouting pipe (52), an upper support ring (53) and a lower support ring (54) are arranged between the extension section pile rod (51) and the extension section built-in grouting pipe (52), and the upper support ring (53) and the lower support ring (54) are used for keeping the extension section pile rod (51) and the extension section built-in grouting pipe (52) coaxial;

the upper end of each lengthening section pile rod (51) is provided with an internal thread, the lower end of each lengthening section pile rod (51) is provided with an external thread, the upper end of each lengthening section built-in grouting pipe (52) is provided with an external thread, and the lower end of each lengthening section built-in grouting pipe (52) is provided with an internal thread;

in the multiple sections of axially connected steel pile extension sections, the pile rod (51) of the extension section is mutually and independently connected with the built-in grouting pipe (52) of the extension section in the axial direction.

6. Grouting spiral steel pile according to claim 4, characterised in that on the built-in grouting pipe (10) above and below the stop-grouting plug (9) there is fixed one ring-shaped piece (13) each; the outer diameter of the annular sheet (13) is smaller than the inner diameter of the pile rod (5).

7. A method for placing a grouting spiral steel pile, the pile placing equipment comprising a drilling machine with a rotary driving device (2) and a grouting pump, characterized in that the step of placing the grouting spiral steel pile according to claim 4 is:

step one, adjusting a drilling angle after the drilling machine with the rotary driving equipment (2) is in place; aligning the pile tip of the spiral steel pile to a design position, connecting the power output end of the rotary driving device (2) with the pile rod and the built-in grouting pipe of the spiral steel pile through an adapter, wherein the adapter is fixed with the power output end of the rotary driving device (2), and the adapter is in threaded connection with the pile rod and the built-in grouting pipe of the spiral steel pile; mixing cement slurry according to the cement mixing amount and the water-cement ratio required by design; determining the drilling speed of the spiral steel pile and the grouting flow rate of the grouting pump,

step two, starting a grouting pump to enable cement slurry to be sequentially conveyed to a pile tip (7) at the bottom of the pile rod along a grouting pipe (1) connected with the grouting pump and a built-in grouting pipe (10) in the pile rod, and enabling the cement slurry to flow out of a slurry outlet hole (6); at the moment, the rotary driving device (2) is started to enable the spiral steel pile to rotate and drill at a set drilling speed, the spiral blade (4) is screwed into the soil, cement slurry is continuously injected at a set grouting flow rate while screwing in, the grouting pressure is gradually and stably increased, and the grouting pump is stopped when the top of the spiral steel pile is drilled to be close to the ground along with the drilling; controlling the rotary driving equipment (2) to rotate reversely, and loosening the connection between the adapter and the top of the spiral steel pile and the built-in grouting pipe; the rotary driving device (2) and the output end are lifted upwards by a certain height;

step three, taking a section of the steel pile lengthening section in the spiral steel pile according to claim 5, firmly connecting the bottom end of the pile rod and the built-in grouting pipe of the section of the steel pile lengthening section with the pile rod of the previous section of the steel pile and the top end of the built-in grouting pipe respectively, and connecting the pile rod of the section of the steel pile lengthening section and the top end of the built-in grouting pipe with the lower end of the adapter; returning to the step two, completing the connection, the screwing-in and the grouting of all the spiral steel piles;

step four, continuing to keep grouting, stopping grouting by a grouting pump when cement grout returns to the ground from the pile hole wall, controlling the rotary driving equipment (2) to rotate reversely, and loosening the connection between the adapter and the uppermost section of the steel pile extension section;

locking the built-in grouting pipes of the lengthened section in the uppermost section of the steel pile lengthened section by using a lock, connecting the lock with the rotary driving device (2), lifting the rotary driving device (2) to pull out all the built-in grouting pipes, and simultaneously pulling out all the support rings, the upper support rings, the lower support rings and the grout stop plugs together under the action of the annular sheets (13) in the spiral steel pile as claimed in claim 6; disassembling the built-in grouting pipe, and washing the grouting pipe with clear water for repeated use;

and fifthly, completing the construction of one spiral steel pile, removing the equipment, and performing the pile planting construction of the next spiral steel pile.

8. The pile planting method of the grouting spiral steel pile according to claim 7, wherein between the fourth step and the fifth step, concrete is poured into the pile rod according to design requirements to improve the vertical compression resistance of the pile rod.

9. A pile-planting method for grouting spiral steel piles as claimed in claim 3 or 7, wherein cement is added to the cement grout in an amount of 12 to 40% of the natural weight of the reinforced soil; the water cement ratio is the weight ratio of water to cement, and is 0.4-2.0.

10. The pile planting method for the grouting spiral steel pile as claimed in claim 3 or 7, wherein the drilling machine with the rotary driving device (2) drives the spiral steel pile to have a drilling speed of 0.2-1.0 m/min.

Technical Field

The invention relates to a spiral steel pile for reinforcing a foundation, in particular to a grouting spiral steel pile.

Background

Foundations often face several problems for several reasons: 1) bearing capacity and stability problems; 2) compression and differential settlement problems; 3) leakage problems; 4) problems with liquefaction; 5) special soil is a special problem. When one or more of the five problems of the natural foundation exist, foundation treatment measures are needed to ensure the safety and normal use of the superstructure.

At present, in the field of foundation treatment and reinforcement in China, concrete pile bodies mainly made of cement binding materials are mainly applied to small piles. Because the concrete material exerts the slow reason of intensity, can't satisfy some special engineering requirements. Some precast piles are increasingly widely used because they avoid the problem of cast-in-place construction. Steel piles, which are one type of precast piles, are also used for foundation reinforcement in many fields.

The spiral steel pile is introduced into China in the early 90 s of the 20 th century, and the application in the field of photovoltaic power stations is more. The novel screw driver has the advantages of no need of earth excavation, direct screwing, lowest ecological damage, capability of directly bearing load and the like. Usually, the spiral steel pile is provided with a plurality of blades to achieve the purposes of no waste soil generation during use and labor saving during screwing. However, since the spiral steel pile is directly screwed into the soil, the disturbance to the soil around the pile providing the bearing capacity is huge, the disturbed soil around the pile needs a long time to recover and is difficult to completely recover to the original structural state, and in addition, the spiral steel pile is difficult to screw in the harder soil layer. Therefore, for the popularization and the use of the spiral steel pile, the problems of disturbance to soil and construction to harder soil layers in the screwing process must be solved.

At present, the reinforcement of the existing buildings is increased year by year, for example, the existing multi-storey buildings are additionally provided with elevator shaft structure foundations, the foundation reinforcement and reconstruction of old residential districts, the reinforcement of bridges, road embankments and side slopes and other construction sites need to be carried out the reinforcement of foundations and foundations so as to improve the strength and the stability of the foundations, and the reinforcement of the foundation is often required to be carried out the piling or the pile planting operation. The spiral steel pile is one of pile types for reinforcing foundation, and is formed from cylindrical steel pipe and one or several spiral blades which are vertically winded round the steel pipe (pile bar) and are independently arranged at intervals, and the pile-planting mode adopts rotary pile body and utilizes the spiral blades to make spinning and inserting into soil. In the process of steel pile burying, because helical blade is to the disturbance of the soil body around, must make the intensity that is located the soil body around the steel pile reduce to some extent, at the in-process that the steel pile buried, in case meet closely knit sand bed, then the burying of steel pile is more difficult.

Disclosure of Invention

Aiming at the prior art, the invention provides a grouting spiral steel pile for foundation reinforcement and a pile planting method thereof, thereby solving the problem that the pile planting of the spiral steel pile adopting the traditional structure is difficult. The bolt steel pile with the structure reduces the resistance of the pile body to be spun into the soil on one hand and fills the soil mass at the pile end on the side of the pile with cement slurry on the other hand to improve the strength of the soil mass and greatly improve the bearing capacity of the spiral steel pile in the pile planting process.

In order to solve the technical problems, the invention provides a grouting spiral steel pile for foundation reinforcement, which has the basic technical scheme that the grouting spiral steel pile comprises a pile rod, wherein the pile rod is a steel pipe, the top of the pile rod is provided with a first interface, the first interface is connected with a power output end of a rotary driving device through a connecting structure, the bottom of the pile rod is a pile tip, the outer rotary surface of the pile rod is provided with a spiral blade, and the pile tip is provided with a plurality of slurry outlet holes communicated with the pile rod; the power output end of the rotary driving device is connected to the grouting pipe.

Further, another technical scheme of the grouting spiral steel pile is that a built-in grouting pipe is arranged in the pile rod, a first connector of the pile rod is provided with internal threads, and the upper end of the built-in grouting pipe is provided with external threads; the output end of the rotary driving device is fixed with the upper end of an adapter, and the lower end of the adapter is simultaneously connected with the built-in grouting pipe and the first interface of the pile rod; the bottom of the built-in grouting pipe is positioned above the pile tip, a grout stop plug is arranged between an outer revolution surface at the bottom end of the built-in grouting pipe and an inner revolution surface of the pile rod, and all grout outlets are positioned below the grout stop plug; and a support ring is arranged between the upper end of the pile rod and the upper end of the built-in grouting pipe, and the support ring and the grout stopping plug are used for keeping the built-in grouting pipe and the pile rod coaxial.

The invention also comprises N sections of steel pile lengthening sections, each section of steel pile lengthening section comprises a lengthening section pile rod and a helical blade arranged on the outer rotating surface of the pile rod, and both ends of each section of steel pile lengthening section are in threaded connection with the connected steel pile lengthening section or helical steel pile.

Meanwhile, the invention also provides a pile planting method of the grouting spiral steel pile, pile planting equipment comprises a drilling machine with rotary driving equipment and a grouting pump, and the step of implanting is as follows:

step one, adjusting a drilling angle after the drilling machine with the rotary driving equipment is in place; aligning the pile tip of the spiral steel pile to a design position, connecting the top of the pile rod of the spiral steel pile with the power output end of a rotary driving device, and mixing cement slurry according to the cement mixing amount and the water cement ratio required by the design; determining the drilling speed of the spiral steel pile and the grouting flow rate of the grouting pump;

step two, starting a grouting pump to enable cement slurry to be sequentially conveyed to a pile tip at the bottom of the pile rod along a grouting pipe and a pile rod inner cavity which are connected with the grouting pump, and enabling the cement slurry to flow out of a slurry outlet; at the moment, the rotary driving equipment is started to enable the spiral steel pile to rotate and drill at a set drilling speed, the spiral blades are screwed into the soil, cement slurry is continuously injected according to a set grouting flow rate while screwing in, the grouting pressure is gradually and stably increased, and the grouting pump is stopped when the top of the spiral steel pile is drilled to be close to the ground along with the drilling; controlling the rotary driving equipment to rotate reversely, and loosening the connection between the rotary driving equipment and the top of the spiral steel pile; and the rotary driving device and the output end are lifted upwards by a certain height;

step three, taking a section of steel pile lengthening section, firmly connecting the bottom end of the pile rod of the section of steel pile lengthening section with the top end of the previous section of pile rod, and connecting the rotary driving equipment with the top end of the pile rod of the section of steel pile lengthening section; returning to the step two, completing the connection, the screwing-in and the grouting of all the spiral steel piles;

step four, continuing to keep grouting, stopping grouting by a grouting pump when cement grout returns to the ground from the pile hole wall, controlling the rotary driving equipment to rotate reversely, and loosening the connection between the rotary driving equipment and the top of the spiral steel pile;

and fifthly, putting graded gravel and cement slurry in the inner cavity of the pile rod into the pile rod, tamping to form concrete so as to improve the vertical compression resistance of the pile rod, completing the construction of one spiral steel pile, removing the equipment, and performing the pile planting construction of the next spiral steel pile.

If the implantation method of the spiral steel pile with the built-in grouting pipe in the pile rod is different from the basic method, the implantation method only comprises the following steps:

in the first step, the power output end of a rotary driving device is connected with a pile rod and a built-in grouting pipe of a spiral steel pile through an adapter, the adapter is fixed with the rotary driving device, and the adapter is in threaded connection with the pile rod and the built-in grouting pipe of the spiral steel pile;

in the second step, after stopping grouting by the grouting pump, controlling the rotary driving equipment to rotate reversely, and loosening the connection between the adapter and the top of the spiral steel pile and the built-in grouting pipe; and the output end of the rotary driving device is lifted upwards by a certain height;

in the third step, the bottom ends of the pile rod and the built-in grouting pipe of the lengthened section of the steel pile are respectively and firmly connected with the top ends of the pile rod and the built-in grouting pipe of the previous section of the steel pile, and the pile rod and the top ends of the built-in grouting pipes of the lengthened section of the steel pile are both connected with the lower end of the adapter, namely in the lengthened sections of the steel pile which are axially connected, the pile rod of the lengthened section and the built-in grouting pipe of the lengthened section are mutually and independently connected in the axial direction;

and in the fourth step, after the loosening conversion joint is connected with the lengthened section of the uppermost steel pile, the built-in grouting pipes of the lengthened section in the lengthened section of the uppermost steel pile are locked by using the lock, the lock is connected with the rotary driving device, the rotary driving device is lifted to pull out all the built-in grouting pipes, the built-in grouting pipes are disassembled, and the steel pile is washed clean by using clean water for reuse.

And fifthly, pouring concrete into the pile rod according to design requirements to improve the vertical compressive property of the pile rod, completing the construction of one spiral steel pile, removing the equipment, and performing the pile planting construction of the next spiral steel pile.

Compared with the prior art, the invention has the beneficial effects that:

according to the bolt steel pile with the structure, in the pile planting process, a steel pipe (pile rod) central channel is utilized or a grouting pipeline (namely a built-in grouting pipe) is independently arranged, a pile tip is provided with a grouting hole, cement grout with a certain water cement ratio is continuously injected in the pile body spinning-in process, the injection flow of the cement grout is matched with the spinning-in speed of pile soil, and the injected cement grout can soften a hard soil layer possibly met by the pile tip, so that the pile body can be smoothly implanted; cement slurry permeates into the pile surrounding soil layer damaged and disturbed by screwing the helical blades, and the soil layer is solidified and reinforced, so that the bearing capacity of the pile is improved; because cement slurry is injected in the pile planting process, soil around the pile is softened during pile planting, the effect of soil squeezing during pile body planting is further reduced, and the influence on the foundation of the nearby building is further reduced; the pile bearing capacity fully utilizes the shearing friction resistance effect of the column body formed by the helical blades and the cement reinforced soil between the helical blades on the foundation soil at the outer side, so that less steel is used to obtain higher bearing capacity, and the energy-saving effect is obvious; the pile planting process has no pollution such as soil discharge, slurry discharge and the like, and is green and environment-friendly.

Drawings

FIG. 1 is a schematic structural diagram of a first embodiment of a grouting spiral steel pile of the present invention;

FIG. 2 is a schematic structural diagram of a second embodiment of a grouting spiral steel pile of the present invention;

FIG. 3 is a schematic structural view of a helical blade of the helical steel pile;

FIG. 4 is a schematic structural view of another helical blade of the helical steel pile;

fig. 5 is a schematic structural view of an elongated section of a steel pile according to the present invention.

In the figure:

1-slip casting pipe 2-rotation driving device

3-first interface 4-helical blade

5-pile rod 6-grout outlet

7-pile tip 8-ground

9-stop-grouting plug 10-built-in grouting pipe

11-support ring 12-adapter

13-ring piece 51-lengthening section pile rod

52-extension section built-in grouting pipe 53-upper support ring

54-lower support ring

Detailed Description

The design idea of the grouting spiral steel pile is that one or more grout outlet holes are formed in the pile tip of the bottom of the pile rod of the spiral steel pile on the premise of meeting the requirements of rigidity and strength, when the pile is planted, the pile rod is rotated and pressure is applied along the pile rod, cement grout is injected into the pile rod from the pile top in the steel pile implanting process by matching with a grouting pipe, namely, the cement grout is injected into the pile bottom while the pile body is spun into the soil, and the cement grout is sprayed out from the grout outlet holes of the pile tip, so that the resistance of spinning into the soil of the pile body is reduced, and on the other hand, the cement grout fills a gap formed by the spiral blade rotating to damage the soil body on the pile side, and the soil body on the pile side is reinforced, so that the strength of the soil body is improved, and the bearing capacity of the spiral steel pile is greatly improved.

The invention will be further described with reference to the following figures and specific examples, which are not intended to limit the invention in any way.