Square hole drilling pile hole forming apparatus and method

Abstract

The embodiment of the application provides a square drill hole pile hole forming equipment and method, wherein the equipment comprises a drilling machine shell, a central shaft drill rod is vertically arranged in the drilling machine shell, a rotating driving device is connected to the top end of the central shaft drill rod, a rotary excavator drill bit is connected to the bottom end of the central shaft drill rod, helical blades are fixed to the outer wall of the central shaft drill rod, the rotating driving device drives the central shaft drill rod, drives the rotary excavator drill bit to rotate and drill to form a circular hole, an impact driving device is arranged at the bottom of the drilling machine shell, four impact drill bits are connected to the output end of the impact driving device, the impact drill bits are arranged at the four corners of the bottom periphery of the rotary excavator drill bit, the impact drill bits vertically move up and down, reciprocating rock breaking is realized, the circular hole is reamed, and finally a square hole is formed. The application can realize full-automatic mechanical drilling, realize square hole forming at one time, has wide application range, small environmental pollution and low overall equipment cost.

Description

Technical Field

[0001] This application relates to the field of pile foundation engineering, specifically to a square bored pile drilling equipment and method. Background Technology

[0002] In the field of drilling engineering technology, geological conditions determine the type of drilling method, which in turn determines the type of drilling equipment. Compared with circular piles, square piles have a larger lateral friction area under the condition of equal cross-section and equal material, thereby increasing the lateral friction force of the pile and significantly increasing the lateral bearing capacity of the pile. In deep foundation pit and high slope engineering, as anti-slide piles, square piles have significantly better mechanical properties than circular piles.

[0003] However, existing methods for forming large-size square piles primarily rely on manual excavation, which is inefficient and dangerous. The technology for forming square piles is still immature. Theoretically, methods for forming square piles include multi-bit rotary drilling, Reuleaux triangular drill bit rotary drilling, and moving drill rod rotary drilling, but none have been translated into practical, mature machinery and construction methods. Common mechanical construction equipment typically involves first drilling a round hole with a rotary drilling rig, and then using other equipment to shape it into a square hole, which is inefficient and difficult to complete in one operation. Summary of the Invention

[0004] To address one of the aforementioned technical deficiencies, according to a first aspect of the present application, a square bored pile drilling equipment is provided, comprising a drilling rig housing, a central drill rod vertically disposed within the drilling rig housing, a rotary drive device connected to the top end of the central drill rod, a rotary drilling bit connected to the bottom end of the central drill rod extending beyond the bottom of the drilling rig housing, an impact drive device disposed at the bottom of the drilling rig housing, four impact drill bits connected to the output end of the impact drive device, the impact drill bits being disposed at the four outer corners of the bottom periphery of the rotary drilling bit, and the working plane of the impact drill bits being higher than the working plane of the rotary drilling bit.

[0005] Furthermore, the square bored pile drilling equipment also includes a main unit traveling part. The extended arm of the main unit traveling part is connected to a mast through a connector. The drilling rig housing is located on one side of the mast. The rotary drive device is located on the mast and above the drilling rig housing. The impact drive device is located on the mast and on the bottom side of the drilling rig housing. The drilling rig housing, the rotary drive device, and the impact drive device can be raised or lowered vertically relative to the mast in sync.

[0006] Furthermore, the impact drill bit is a beak-shaped drill bit, the cross-section of the drill housing is circular, and the beak-shaped drill bits are respectively set at the four corners of the bottom periphery of the drill housing to form a square.

[0007] Furthermore, the outer wall of the central drill rod is provided with helical blades, the diameter of which is larger than the diameter of the rotary drilling bit, and a slag outlet is provided on one side of the top of the drilling rig housing.

[0008] Furthermore, the output end of the impact drive device is connected to a base plate. The outer contour of the base plate is larger than the outer contour of the drill housing. The base plate is located on the bottom periphery of the drill housing and has an inner circle and outer square shape. A clearance hole is opened in the middle of the base plate. The diameter of the clearance hole is larger than the diameter of the spiral blade. The base plate is connected to the top of the impact drill bit through the impact drill rod.

[0009] Furthermore, four grooves are provided along the four corners of the bottom plate towards the center of the bottom plate. The tops of the four impact drill rods are slidably connected to the four grooves respectively. Four propulsion mechanisms are also provided near the grooves at the bottom of the bottom plate. The output end of the propulsion mechanism can drive the impact drill rod to move in the groove to achieve the enlargement of square holes of different sizes.

[0010] Furthermore, four movable supports are symmetrically arranged on the outer side wall of the bottom of the drilling rig housing. The four movable supports are staggered with four impact drill bits. Multiple vertically stacked protective plates are clamped on the movable supports on the same side wall. The four protective plates in the same layer are interlocked with each other. The movable supports can drive the protective plates to slide vertically along the outer wall of the drilling rig housing. When drilling, the impact drill rod slides to the outermost side, and the top of the impact drill bit prevents the protective plate from sinking. After drilling is completed, the impact drill rod slides towards the center of the bottom plate to make way for the protective plate, and the protective plate sinks to the bottom of the hole.

[0011] According to a second aspect of the embodiments of this application, a method for forming a square bored pile is provided, including any of the square bored pile forming equipment described above, comprising the following steps:

[0012] ① Calculate the shear and bending strength of the anti-slide piles and the displacement and deformation requirements of the pile top based on the slope height, stratum information and upper load, and determine the cross-sectional dimensions, pile length, pile spacing and their arrangement of the anti-slide piles;

[0013] ②Prefabricated steel plates or reinforced concrete are used as wall panels in the factory;

[0014] ③ Level the site. On sloping sections, construct the construction platform by excavating large steps. The step width should not be less than 5m. Ensure the stability of the construction equipment to prevent it from tipping over or tilting.

[0015] ④ Measure and lay out the lines, position the drilling rig, fix the drill rod support, and select the matching drill bit according to the size of the anti-slide pile;

[0016] ⑤ The rotary drive device first drives the central shaft drill rod to drive the rotary drill bit to drill, and simultaneously drives the spiral blades to carry the drill cuttings out of the cuttings outlet by the rotation of the spiral blades;

[0017] ⑥ After the rotary drilling bit has drilled about 0.5m, the impact drive device is activated, which drives the four-corner beak-type impact drill bit to impact and enlarge the hole. The enlarged hole slag is squeezed to the middle and carried out by the rotating spiral blades.

[0018] Furthermore, the method for forming square bored piles also includes the following steps:

[0019] ⑦ After the impact enlargement hole is 1-2m deep, drilling is paused. A movable support is used to divide the precast steel plate or reinforced concrete retaining wall into four sections and place them against the four walls of the excavated hole. Each section is 1-2m long and is driven by the movable support to sink synchronously with the drilling.

[0020] ⑧ Continue drilling for 1-2m, then pause drilling and use small hoisting equipment to hoist the four retaining walls to the top of the lower retaining wall and snap them together; repeat steps ⑥ to ⑧ until the designed excavation depth is reached.

[0021] Furthermore, the method for forming square bored piles also includes the following steps:

[0022] ⑨ The impact drill rod is driven to move in the groove by the propulsion mechanism, so that the four-cornered beak drill bit slides to the inside of the wall plate, and at the same time the wall plate is driven to sink to the bottom of the hole by the movable bracket;

[0023] ⑩ Raise the drill rod and drill bit, move the drilling rig, and use the skip pile method to excavate the next pile hole. Subsequent construction, such as lowering the steel cage and pouring the pile body concrete, is carried out using conventional construction techniques.

[0024] The square bored pile drilling equipment and method provided in this application mainly include three parts: rock breaking, slag removal, and wall protection. The rock breaking part is achieved by a central rotary drilling hole plus four-corner impact reaming. The central rotary drilling uses a rotary drill bit for rotary drilling, and the impact reaming uses a four-corner beak-shaped drill bit for vertical reciprocating impact. The rotary drilling and impact reaming are carried out in a staggered, step-by-step cycle. The slag removal part is achieved by rotating long spiral blades to remove slag. The wall protection part is achieved by a movable support that drives the wall protection plate for hoisting and pre-positioning. Using the square bored pile drilling equipment and method provided in this application, fully automatic mechanical drilling, slag removal, and wall protection are followed, eliminating the need for construction personnel to work at the bottom of the hole, and the square hole formation requirement can be achieved in one operation. Attached Figure Description

[0025] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0026] Figure 1 This is a schematic diagram of the structure of the square bored pile drilling equipment provided in the embodiments of this application;

[0027] Figure 2 A schematic diagram of the overall structure of the main unit traveling part of the square bored pile drilling equipment provided in the embodiments of this application;

[0028] Figure 3 This is a schematic diagram of the structure of the base plate provided in the embodiments of this application;

[0029] Figure 4This is a schematic diagram of the structure of the beak-shaped drill bit provided in the embodiments of this application;

[0030] Among them, 10 is the drilling rig housing, 101 is the slag outlet, 20 is the central drill rod, 201 is the spiral blade, 30 is the rotary drive device, 40 is the rotary drilling bit, 50 is the impact drive device, 501 is the base plate, 502 is the chute, 503 is the propulsion mechanism, 504 is the clearance hole, 60 is the impact drill bit, 601 is the beak drill bit, 602 is the impact drill rod, 70 is the main unit traveling part, 701 is the mast, 80 is the movable support, and 801 is the wall plate. Detailed Implementation

[0031] To make the technical solutions and advantages in the embodiments of this application clearer, the following description is provided in conjunction with the appendix. Figure 1-4 The exemplary embodiments of this application will be described in further detail below. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0032] In the process of realizing this application, the inventors discovered that the existing pile construction technology is divided into two types: mechanical drilling and manual drilling. Manually excavated piles require a lot of manpower, the drilling speed is slow, and there are great safety hazards. Mechanical drilling, on the other hand, forms a circular hole by rotating the mechanical chassis, so most mechanically drilled holes are circular.

[0033] Manually excavated cast-in-place piles mainly employ excavation with a Luoyang shovel or small-scale blasting and concrete wall protection. The main types of machinery used for forming cast-in-place piles include: driven cast-in-place pile machines, long (short) auger drilling rigs, forward and reverse circulation mud (casing) wall protection drilling rigs, and rotary drilling rigs. In design and practical engineering applications, the above-mentioned traditional square pile forming methods have the following specific problems:

[0034] 1. Significant safety hazards: Due to limitations in pile-forming technology and construction machinery, existing large-size square piles still mainly rely on manual excavation methods. Under the influence of loose soil layers and groundwater, hole collapse accidents are prone to occur, resulting in high construction safety risks.

[0035] 2. The technology for forming square piles is not mature: At present, in theory, there are methods for forming square piles, such as multi-drill mechanical rotary drilling, Reuleaux triangular drill rotary drilling, and moving drill rod rotary drilling, but none of them have been transformed into practical and mature mechanical equipment and construction methods.

[0036] 3. Limited applicable formations: There are many types of existing drilling equipment, but a single drilling method can only be adapted to a few formation conditions. This is mainly because rock breaking drilling methods and slag removal drilling processes are often not compatible with each other.

[0037] 4. Small pile diameter: Mechanical dry-operation bored piles mainly include pipe-driven bored pile machines, short spiral drilling rigs, and long spiral drilling rigs. Due to the limitations of pile frame height and power head, the pile diameter is generally small, usually less than 0.8m.

[0038] 5. Large mud discharge and environmental pollution: The main types of drilling rigs for positive and reverse circulation mud (casing) wall protection include positive and reverse circulation drilling rigs, submersible drilling rigs, impact drilling rigs, rotary drilling rigs, etc. The above-mentioned drilling equipment is simple and easy to operate, and is widely used in China. Their common disadvantage is that they consume a lot of water and discharge a lot of mud, which pollutes the environment.

[0039] 6. High cost and high construction difficulty: Rotary drilling rigs are a relatively advanced construction method for bored pile construction that has been developed in recent years. The main features of this construction method are high construction efficiency and less mud pollution. However, the equipment cost is high, the equipment operation is complex and difficult to master, and it is difficult to penetrate relatively hard rock bearing layers.

[0040] Example 1

[0041] To address the aforementioned problems, Embodiment 1 of this application provides a square bored pile drilling equipment, such as... Figure 1-4 As shown, the system includes a drilling rig housing 10, inside which a central drill rod 20 is vertically installed. A rotary drive device 30 is connected to the top of the central drill rod 20. The bottom end of the central drill rod 20 extends out of the bottom of the drilling rig housing 10 and is connected to a rotary drilling bit 40. The rotary drilling bit 40 is coaxially arranged with the central drill rod 20. The outer wall of the bottom end of the central drill rod 20 is integrally welded with an internal helical thread within a certain range. The rotary drilling bit 40 is threadedly connected to the bottom end of the central drill rod 20. Specifically, the rotary drilling bit 40 can be an alloy drill bit. The rotary drive device 30 drives the central drill rod 20, causing the rotary drilling bit 40 to rotate. An impact drive device 50 is provided at the bottom of the drilling rig housing 10. The output end of the impact drive device 50 is connected to four impact drill bits 60. The impact drive device 50 drives the impact drill bits 60 to achieve reciprocating rock breaking. The impact drill bits 60 are located at the four corners of the bottom periphery of the rotary drilling bit 40, and the working plane of the impact drill bits 60 is higher than the working plane of the rotary drilling bit 40.

[0042] In practice, the rotary drive device 30 first drives the central drill rod 20, which in turn drives the rotary drill bit 40 to rotate, thus enabling the rotary drill bit to drill. A circular hole is formed in the ground at the drilled location. After drilling to a certain depth, the working plane of the impact drill bit 60 contacts the ground at the drilled location. The impact drive device 50 drives the impact drill bit 60 to move back and forth vertically, thus achieving reciprocating rock breaking and enlarging the previously formed circular hole to finally form a square hole.

[0043] The square bored pile drilling equipment provided in this embodiment improves upon existing rotary drill bit and rod equipment and power drive output methods. It combines rotary and impact power drive devices, fully utilizing the advantages of large rotary drilling area and high impact drilling speed. The rotary drill bit and impact drill bit are driven separately, integrating the two drilling methods into one: first, a circular hole is formed in the center, then the four corners are enlarged to ultimately form a square hole. This overcomes the bottleneck that most existing mechanical drilling for bored piles is limited to circular shapes, effectively solving the problem of mechanical drilling for large-size square piles. Furthermore, the entire process is mechanized, eliminating the need for manual excavation and cleaning, thus avoiding the risk of personnel injury due to hole collapse and water inrush.

[0044] The rotary drilling bit and the impact drilling bit adopt two sets of power output systems. The pile size is the sum of the pile size of a single rotary drilling rig and the pile size of an impact drilling rig. It can form a square hole with a side length of 1.5 to 3m, which meets most of the size requirements of existing anti-slide piles.

[0045] As a preferred embodiment, the square bored pile drilling equipment also includes a main unit traveling part 70, which enables the equipment to travel and the installation of the remaining parts. The extension arm of the main unit traveling part 70 is connected to a mast 701 via a connector. The drill housing 10 is located on one side of the mast 701, the rotary drive device 30 is located on the mast 701 and above the drill housing 10, and the impact drive device 50 is located on the mast 701 and on the bottom side of the drill housing 10. The drill housing 10, the rotary drive device 30, and the impact drive device 50 can be synchronously and vertically raised or lowered relative to the mast 701.

[0046] As a preferred embodiment, the impact drill bit 60 is a beak-shaped drill bit 601. This structure is narrower at the bottom and wider at the top, which is beneficial for hole enlargement, rock drilling, and soil breaking. The cross-section of the drill housing 10 is circular, and the beak-shaped drill bits 601 are respectively arranged at the four corners of the bottom periphery of the drill housing 10 to form a square. It should be noted that the shape of the impact drill bit 60 includes, but is not limited to, a beak-shaped drill bit, and similar structural forms that are narrower at the bottom and wider at the top should also fall within the range of geometric structural forms of this drill bit.

[0047] As a preferred embodiment, the outer wall of the central drill rod 20 is provided with a helical blade 201, the diameter of which is larger than the diameter of the rotary drill bit 40. A slag outlet 101 is provided on one side of the top of the drilling rig housing 10. Specifically, the rotary drill bit 40 and the helical blade 201 rotate coaxially at different speeds, enabling simultaneous drilling and slag removal, which is applicable to drilling in all soil types, soft rock, and some hard rock formations.

[0048] As a preferred embodiment, the output end of the impact drive device 50 is connected to a base plate 501. The outer contour of the base plate 501 is larger than the outer contour of the drill housing 10. The base plate 501 is located on the bottom periphery of the drill housing 10 and has an inner circle and outer square shape. A clearance hole 504 is provided in the middle of the base plate 501. The diameter of the clearance hole 504 is larger than the diameter of the spiral blade 201. The base plate 501 is connected to the top of the impact drill bit 60 through the impact drill rod 602.

[0049] As a preferred embodiment, four grooves 502 are formed along the four corners of the bottom of the base plate 501 towards its center. The tops of the four impact drill rods 602 are slidably connected to the four grooves 502 respectively. Near the grooves 502 at the bottom of the base plate 501, four propulsion mechanisms 503 are also provided. The output end of the propulsion mechanism 503 can drive the impact drill rods 602 to move within the grooves 502, thereby enlarging square holes of different sizes. The four propulsion mechanisms 503 synchronously advance or retract the impact drill rods 602, ensuring that the holes formed by the four impact drill bits 60 are always square. Furthermore, when the impact drill bits 60 are drilling, the propulsion mechanisms 503 are not engaged, and the impact drill rods 602 are locked within the grooves 502.

[0050] In practice, the impact drill bit 60 can slide in the groove 502 of the base plate 501 under the action of the propulsion mechanism 503. It can not only change the size of the square hole according to different needs, but also release the restriction of the impact drill bit 60 on the wall plate 801 after retraction, so that the wall plate 801 can sink smoothly.

[0051] As a preferred embodiment, four movable supports 80 are symmetrically arranged on the bottom outer sidewall of the drilling rig housing 10. The four movable supports 80 are staggered with four impact drill bits 60. The movable supports 80 are located below the impact drive device 50 near the ground, with a height of about twice the length of the protective wall section. Multiple vertically stacked protective wall plates 801 are clamped on the movable supports 80 on the same sidewall. The protective wall plates 801 are hoisted and pre-positioned by a hydraulic movable rod. The protective wall plates 801 can be prefabricated steel plates or reinforced concrete protective wall plates. The four protective wall plates 801 on the same layer are interlocked with each other. The movable supports 80 can drive the protective wall plates 801 to slide vertically along the outer wall of the drilling rig housing 10. During drilling, the impact drill rod 602 slides to the outermost side, and the top of the impact drill bit 60 blocks the protective wall plate 801 from sinking. After drilling is completed, the impact drill rod 602 slides towards the center of the bottom plate 501 to make way for the protective wall plate 801, and the protective wall plate 801 sinks to the bottom of the hole.

[0052] By using drilling equipment to pre-install steel sheet piles in sections during mechanical drilling, the entire process is carried out using dry construction methods, eliminating the need for mud wall protection and avoiding the environmental pollution caused by mud wall protection.

[0053] The square bored pile drilling equipment provided in this embodiment breaks through the bottleneck that most existing mechanical drilling for cast-in-place piles is limited to circular shapes, effectively solving the problem of mechanical drilling for large-sized square piles. It employs both rotary drilling and impact drilling methods, suitable for drilling in soil, soft rock, and some hard rock formations. By adjusting the drill bit size and the sliding adjustment of the impact drill bit on the base plate, it can meet the drilling requirements for most conventional anti-slide piles, making it widely applicable. Precast retaining walls are simultaneously installed during excavation, eliminating the need for mud wall protection and reducing environmental pollution from mud wall protection. Except for the beak-type impact drill bit, all other drill bits, drill rods, and drive devices can be modified using existing mature technologies, keeping equipment development costs controllable. Steel plates or reinforced concrete retaining walls can be prefabricated in factories, resulting in low overall project costs.

[0054] Example 2

[0055] Before implementing this patent, the engineering machinery was modified and invented simultaneously according to structural requirements. The stress calculation of the pile body was performed based on the characteristics of the project, determining the pile dimensions, pile length, spacing, and concrete retaining wall cross-sectional dimensions. If necessary, on-site simulation tests were conducted to test the compressive and shear strength of the pile material to verify the reliability of the design scheme. Based on Embodiment 1, this application also provides a method for forming square bored piles, including any of the aforementioned square bored pile forming equipment, comprising the following steps:

[0056] ① Calculate the shear and bending strength of the anti-slide piles and the displacement and deformation requirements of the pile top based on the slope height, stratum information and upper load, and determine the cross-sectional dimensions, pile length, pile spacing and their arrangement of the anti-slide piles;

[0057] ②Prefabricated steel plates or reinforced concrete are used as wall panels in the factory;

[0058] ③ Level the site. On sloping sections, construct the construction platform by excavating large steps. The step width should not be less than 5m. Ensure the stability of the construction equipment to prevent it from tipping over or tilting.

[0059] ④ Measure and lay out the lines, position the drilling rig, fix the drill rod support, and select the matching drill bit according to the size of the anti-slide pile;

[0060] ⑤ The rotary drive device first drives the central shaft drill rod to drive the rotary drill bit to drill, and simultaneously drives the spiral blades to carry the drill cuttings out of the cuttings outlet by the rotation of the spiral blades;

[0061] ⑥ After the rotary drilling bit has drilled about 0.5m, the impact drive device is activated, which drives the four-corner beak-type impact drill bit to impact and enlarge the hole. The enlarged hole slag is squeezed to the middle and carried out by the rotating spiral blades.

[0062] It should be noted that drilling a circular hole and then expanding the four corners to form a square hole at the same pile location in two separate operations both fall within the scope of this hole-forming method.

[0063] As a preferred embodiment, the method for forming square bored piles also includes the following steps:

[0064] ⑦ After the impact enlargement hole is 1-2m deep, drilling is paused. A movable support is used to divide the precast steel plate or reinforced concrete retaining wall into four sections and place them against the four walls of the excavated hole. Each section is 1-2m long and is driven by the movable support to sink synchronously with the drilling.

[0065] ⑧ Continue drilling for 1-2m, then pause drilling and use small hoisting equipment to hoist the four retaining walls to the top of the lower retaining wall and snap them together; repeat steps ⑥ to ⑧ until the designed excavation depth is reached.

[0066] It should be noted that the retaining wall panels can be installed and lowered simultaneously with drilling and excavation, or the precast retaining wall panels can be hoisted and lowered after drilling is completed.

[0067] As a preferred embodiment, the method for forming square bored piles also includes the following steps:

[0068] ⑨ The impact drill rod is driven to move in the groove by the propulsion mechanism, so that the four-cornered beak drill bit slides to the inside of the wall plate, and at the same time the wall plate is driven to sink to the bottom of the hole by the movable bracket;

[0069] ⑩ Raise the drill rod and drill bit, move the drilling rig, and use the skip pile method to excavate the next pile hole. Subsequent construction, such as lowering the steel cage and pouring the pile body concrete, is carried out using conventional construction techniques.

[0070] The square bored pile drilling equipment and method provided in this embodiment employs both rotary and impact power output systems. It primarily uses a central rotary drilling rig to form a circular hole, supplemented by a four-corner beak-type impact drill bit for hole enlargement. The method involves staggered excavation, fully utilizing the mature technology and equipment of rotary drilling rigs to complete most of the hole-forming work. Simultaneously, it leverages the geometric characteristics of the beak-type drill bit to achieve square enlargement at the four corners. Simultaneous drilling and slag removal, along with the synchronous lowering of prefabricated retaining walls via a movable support, forms a complete integrated equipment system for drilling, slag removal, hoisting, and motorization. This application utilizes fully automated mechanical drilling, slag removal, and retaining wall follow-up, eliminating the need for personnel to work at the bottom of the hole. It can achieve the square hole formation requirement in one operation, has a wide range of applications, minimal environmental pollution, low overall equipment cost, and simple operation, making it highly practical.

[0071] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0072] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0073] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0074] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0075] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A square bored pile drilling equipment, characterized in that, The system includes a drilling rig housing (10), inside which a central drill rod (20) is vertically installed. A rotary drive device (30) is connected to the top of the central drill rod (20), and a rotary drilling bit (40) is connected to the bottom of the central drill rod (20) after extending out of the bottom of the drilling rig housing (10). An impact drive device (50) is provided at the bottom of the drilling rig housing (10), and four impact drill bits (60) are connected to the output end of the impact drive device (50). The impact drill bits (60) are located at the four corners of the bottom periphery of the rotary drilling bit (40), and the working plane of the impact drill bits (60) is higher than the working plane of the rotary drilling bit (40). The outer wall of the central drill rod (20) is provided with a spiral blade (201), the diameter of which is larger than the diameter of the rotary drilling bit (40), and a slag outlet (101) is provided on one side of the top of the drilling rig housing (10). The output end of the impact drive device (50) is connected to a base plate (501). The outer contour of the base plate (501) is larger than the outer contour of the drill housing (10). The base plate (501) is located on the bottom periphery of the drill housing (10) and is in the form of an inner circle and an outer square. A clearance hole (504) is provided in the middle of the base plate (501). The diameter of the clearance hole (504) is larger than the diameter of the spiral blade (201). The base plate (501) is connected to the top of the impact drill bit (60) through the impact drill rod (602). The bottom of the base plate (501) has four grooves (502) along the four corners of the base plate (501) toward the center of the base plate (501). The tops of the four impact drill rods (602) are slidably connected to the four grooves (502) respectively. Near the bottom grooves (502) of the base plate (501), there are also four propulsion mechanisms (503). The output end of the propulsion mechanism (503) can drive the impact drill rods (602) to move in the grooves to realize the enlargement of square holes of different sizes. Four movable supports (80) are symmetrically arranged on the bottom outer side wall of the drilling rig housing (10). The four movable supports (80) are staggered with four impact drill bits (60). Multiple vertically stacked protective plates (801) are clamped on the movable supports (80) on the same side wall. The four protective plates (801) on the same layer are clamped to each other. The movable supports (80) can drive the protective plates (801) to slide vertically along the outer wall of the drilling rig housing (10). When drilling, the impact drill rod (602) slides to the outermost side. The top of the impact drill bit (60) blocks the protective plate (801) from sinking. After drilling is completed, the impact drill rod (602) slides towards the center of the bottom plate (501) to make way for the protective plate (801). The protective plate (801) sinks to the bottom of the hole.

2. The square bored pile drilling equipment according to claim 1, characterized in that, It also includes a main unit traveling part (70), the extension arm of which is connected to a mast (701) via a connector. The drill housing (10) is located on one side of the mast (701). The rotary drive device (30) is located on the mast (701) and above the drill housing (10). The impact drive device (50) is located on the mast (701) and at the bottom side of the drill housing (10). The drill housing (10), the rotary drive device (30), and the impact drive device (50) can be raised or lowered vertically relative to the mast (701) in sync.

3. The square bored pile drilling equipment according to claim 1, characterized in that, The impact drill bit (60) is a beak-shaped drill bit (601), the cross-section of the drill housing (10) is circular, and the beak-shaped drill bit (601) is respectively arranged at the four corners of the bottom periphery of the drill housing (10) to form a square.

4. A method for forming a square bored pile, comprising the square bored pile forming equipment as described in claim 3, characterized in that, Includes the following steps: ① Calculate the shear and bending strength of the anti-slide piles and the displacement and deformation requirements of the pile top based on the slope height, stratum information and upper load, and determine the cross-sectional dimensions, pile length, pile spacing and their arrangement of the anti-slide piles; ②Prefabricated steel plates or reinforced concrete are used as wall panels in the factory; ③ Level the site. On sloping sections, construct the construction platform by excavating large steps. The step width should not be less than 5m. Ensure the stability of the construction equipment to prevent it from tipping over or tilting. ④ Measure and lay out the lines, position the drilling rig, fix the drill rod support, and select the matching drill bit according to the size of the anti-slide pile; ⑤ The rotary drive device first drives the central shaft drill rod to drive the rotary drill bit to drill, and simultaneously drives the spiral blades to carry the drill cuttings out of the cuttings outlet by the rotation of the spiral blades; ⑥ After the rotary drilling bit has drilled 0.5m, the impact drive device is activated, which drives the four-corner beak-type impact drill bit to impact and enlarge the hole. The enlarged hole slag is squeezed to the middle and carried out by the rotating spiral blades.

5. The method for forming a square bored pile according to claim 4, characterized in that, It also includes the following steps: ⑦ After the impact enlargement hole is 1-2m deep, drilling is paused. A movable support is used to divide the precast steel plate or reinforced concrete retaining wall into four sections and place them against the four walls of the excavated hole. Each section is 1-2m long and is driven by the movable support to sink synchronously with the drilling. ⑧ Continue drilling for 1-2m, then pause drilling and use small hoisting equipment to hoist the four retaining walls to the top of the lower retaining wall and snap them together; repeat steps ⑥ to ⑧ until the designed excavation depth is reached.

6. The method for forming a square bored pile according to claim 5, characterized in that, It also includes the following steps: ⑨ The impact drill rod is driven to move in the groove by the propulsion mechanism, so that the four-cornered beak drill bit slides to the inside of the wall plate, and at the same time the wall plate is driven to sink to the bottom of the hole by the movable bracket; ⑩ Raise the drill rod and drill bit, move the drilling rig, and use the skip pile method to excavate the next pile hole. Subsequent construction, such as lowering the steel cage and pouring the pile body concrete, is carried out using conventional construction techniques.

Images