Construction method for large-diameter rock-socketed pile rotary excavating full-section cutter drill hole bottom rock surface finishing

Abstract

The present application relates to the technical field of rock-socketed piles, and discloses a large-diameter rock-socketed pile rotary excavating full-section cutter drill hole bottom rock surface trimming construction method, which comprises the following steps: measuring and placing a pile position, and burying a protection cylinder in the pile position; using a drilling machine to drive a rotary excavating drill cylinder to core drilling, so as to form a drill hole; forming a rock surface to be trimmed at the bottom of the drill hole; providing a trimming drill cylinder; replacing the rotary excavating drill cylinder with the trimming drill cylinder, driving the trimming drill cylinder to trim and flatten the rock surface to be trimmed, so as to form a trimmed rock surface; replacing the trimming drill cylinder with a slag salvaging drill bit, and after slag salvaging treatment is performed by using the slag salvaging drill bit, the depth of the trimmed rock surface is measured multiple times, so as to obtain maximum depth data and minimum depth data; and repeating the trimming rock surface operation, so that when the difference between the maximum depth data and the minimum depth data is less than 50 mm, a flat rock surface is formed. By replacing the rotary excavating drill cylinder with the trimming drill cylinder, the drilling machine does not need to be replaced, the concave-convex or stepped hole bottom on the hole bottom rock surface is trimmed and flattened in full section by using a roller bit and an inserted-tooth cutter, and a flat rock surface is formed.

Description

Technical Field

[0001] This invention relates to the technical field of rock-socketed piles, and more specifically, to a method for repairing the rock surface at the bottom of a large-diameter rock-socketed pile hole using a rotary drilling rig with a full-section cutter head. Background Technology

[0002] In hard rock drilling of large-diameter embedded piles with a diameter of 1600mm or more, staged reaming and coring drilling or small-drill array coring drilling is usually adopted. Staged reaming drilling uses a small-diameter rotary drilling rig to drill from the center of the pile to collect the core, gradually increasing the drilling diameter in stages until the designed pile diameter is reached. Small-drill array coring drilling uses the same small-diameter cutting tooth cylinder drill, collects the core sequentially in an array, and then uses a cylinder drill of the designed pile diameter to flatten the entire pile in one go.

[0003] However, they all have the following problems: during the drilling process of rotary drilling rigs, due to the influence of the degree of development of rock fissures and different rock hardness, regardless of whether the staged hole expansion process or the small drill array core sampling process is used, the bottom elevation of the rock core will be different in each drilling and core sampling. Finally, after the hole is formed, the bottom of the hole will be uneven or stepped.

[0004] In existing technologies, core drilling cannot achieve leveling of uneven or stepped hole bottoms. Therefore, in actual construction, most holes are not leveled after drilling, posing a certain risk to the quality of pile formation. Alternatively, a small-diameter cylinder drill biting and fracturing process can be used, where a small-diameter cylinder drill bit is used to drill through multiple holes to fracture and level the uneven rock surface at the bottom of the hole. This process requires repeated movement of the cylinder and multiple slag removals from the bottom of the hole, resulting in slow construction speed and poor treatment effect. Another option is to use a rotary drilling rig equipped with a roller drill bit to grind the bottom of the hole, but this requires changing the drilling rig during construction, which is time-consuming and costly. Summary of the Invention

[0005] The purpose of this invention is to provide a construction method for repairing the rock surface at the bottom of the hole using a full-section rotary cutter bit for large-diameter rock-socketed piles. This method aims to solve the problem in the prior art that it is difficult to handle the unevenness at the bottom of the hole after drilling large-diameter rock-socketed piles in hard rock, resulting in poor pile quality.

[0006] This invention is implemented as follows: a construction method for repairing the rock surface at the bottom of a large-diameter rock-socketed pile hole using a rotary cutter bit, comprising the following construction steps:

[0007] 1) Mark out the pile positions of the rock-socketed piles at the construction site and install casings in the pile positions; provide a drilling rig, which is movably connected to a rotary drilling rig, and use the drilling rig to drive the rotary drilling rig to core drill the casing to form a borehole in the pile position; the bottom of the borehole is located in the rock strata and forms a rock surface to be repaired.

[0008] 2) Provide a dressing drill barrel; the dressing drill barrel includes a barrel with a bottom opening, the bottom opening of the barrel is provided with a bottom plate, the bottom plate covers the bottom opening; the bottom plate has a lower end face arranged downward and an upper end face arranged upward, the bottom of the barrel is welded and fixed to the upper end face, the lower end face is provided with toothed hobs and roller cone drill bits, the roller cone drill bits are arranged at the center and both sides of the lower end face, and multiple toothed hobs are staggered and spaced along the radial direction of the lower end face;

[0009] The rotary drilling barrel is replaced with a trimming drilling barrel, and the trimming drilling barrel is driven by the drilling rig to trim and grind the rock surface to be trimmed, forming a trimmed rock surface.

[0010] 3) Replace the trimming drill bit with a slag-removing drill bit, and use the drilling rig to drive the slag-removing drill bit to remove slag from the bottom of the borehole. Then, measure the depth of the trimmed rock surface in multiple directions multiple times to obtain trimmed rock surface depth data. The trimmed rock surface depth data includes the maximum depth data and the minimum depth data.

[0011] 4) When the difference between the maximum depth data and the minimum depth data is not less than 50mm, repeat steps 2) to 3) above until the difference between the maximum depth data and the minimum depth data is less than 50mm, thus forming a flat rock surface.

[0012] Optionally, the borehole includes an upper borehole located in the soil layer and a lower borehole located in the rock layer, with the upper borehole located above the lower borehole; the rotary drilling rig includes a small-diameter rig, a medium-diameter rig, and a large-diameter rig.

[0013] In step 1), after the upper hole is formed, a small-diameter cylinder driven by a drilling rig is used to core drill towards the center of the upper hole to a set depth to form a primary hole; then, a medium-diameter cylinder driven by a drilling rig is used to core drill to a set depth, and the primary hole is enlarged to form a secondary hole, which is concentrically arranged with the primary hole; then, a large-diameter cylinder driven by a drilling rig is used to core drill to a set depth, and the secondary hole is enlarged to form a lower hole, which is concentrically arranged with the secondary hole, and the upper hole and the lower hole are connected to form the borehole.

[0014] Optionally, in step 1), after the borehole is formed, the bottom of the borehole is cleaned.

[0015] Optionally, in step 1), after cleaning the bottom of the borehole, the depth of the rock surface to be repaired is measured multiple times to obtain the depth data of the rock surface to be repaired.

[0016] In step 2), based on the depth data of the rock surface to be repaired, the drilling rig drives the trimming drill barrel to trim and grind the rock surface to be repaired.

[0017] Optionally, in step 2), the toothed hob is mounted and fixed on the hob bracket, the hob bracket includes a base plate, the upper surface of the base plate is fixed to the lower end face by welding; the two ends of the base plate have mounting brackets that extend downwards respectively, and the two mounting brackets are arranged at intervals to form an installation area;

[0018] A toothed hob is arranged in the installation area. The toothed hob includes a strip-shaped hob shaft and a cylindrical hob tube. The two ends of the hob shaft are fixedly connected to the mounting bracket by bolts. The hob tube that rolls around the hob shaft is sleeved in the middle of the hob shaft. Multiple pointed grinding heads are embedded on the outer surface of the hob tube. The multiple grinding heads are evenly spaced on the hob tube.

[0019] The base plate is rotated horizontally, and the movement trajectory of the hob barrel forms a hob grinding trajectory ring, while the movement trajectory of the roller cone drill bit forms a roller cone grinding trajectory ring. The multiple hob grinding trajectory rings and the multiple roller cone grinding trajectory rings completely cover the lower end face.

[0020] Optionally, the bottom frame of the mounting bracket has two outwardly extending mounting heads, which are spaced apart to form a fixing area, and the end of the hob shaft passes through the fixing area to form a through section;

[0021] The through section is provided with a through hole, and the mounting head is provided with a mounting hole. The mounting hole and the through hole are aligned to form an anchoring channel. The bolt is inserted into the anchoring channel to fix the through section and the mounting head together.

[0022] Optionally, in step 2), the base plate has multiple pressure relief holes formed by cutting, and the pressure relief holes penetrate the base plate from top to bottom.

[0023] Optionally, in step 2), multiple triangular steel frames are welded and fixed on the upper end face. The triangular steel frames include horizontally arranged horizontal sections and longitudinally arranged longitudinal sections. The horizontal sections are welded and fixed on the upper end face, and the longitudinal sections are welded and fixed on the inner wall of the cylinder.

[0024] Optionally, in step 4), the casing has an upper ring extending above the ground plane, and the top of the upper ring has an annular end face; a steel mesh is laid on the annular end face, the mesh has multiple mesh holes, the multiple mesh holes are evenly spaced on the mesh, the mesh presses against the annular end face, and the mesh completely covers the annular end face.

[0025] The outer periphery of the net extends outward to form an outer ring located outside the annular end face, and the outer periphery of the outer ring extends towards the ground plane to form a lower ring; metal chains are respectively connected to both sides of the net, one end of the metal chain is fixedly connected to the net, and the other end of the metal chain is fixedly sleeved on a lifting ring, which is fixedly lifted to the top of the net;

[0026] When construction workers stand on the mesh to measure the depth of the uneven layer, the mesh presses against the annular end face, and the bottom of the lower extension ring presses against the ground plane.

[0027] Optionally, the depth of the uneven layer is measured using an elevation measuring instrument, which includes a body and has an annular inner cavity arranged around the center of the body.

[0028] The machine body has a rollable roller at its center, and a drive structure that can drive the roller to roll is provided inside the machine body. A steel ruler strip wound into a disc shape is provided inside the inner cavity. The steel ruler strip is marked with a scale. The inner end of the steel ruler strip is fixedly connected to the roller. The outer surface of the machine body has a cavity opening that communicates with the inner cavity. The outer end of the steel ruler strip extends outward to the outside of the cavity opening and is fixedly connected to a counterweight. The counterweight is spherical. The width of the steel ruler strip is smaller than the width of the cavity opening.

[0029] The body has an enclosing wall that encloses and forms the cavity opening. An elastic ring is provided on the enclosing wall, and the elastic ring is arranged around the enclosing wall along its circumferential direction. The outer periphery of the elastic ring is relatively fixed to the enclosing wall, and the inner periphery of the elastic ring encloses and forms a channel opening. The steel ruler has multiple deceleration sections, which are evenly spaced along the length of the steel ruler. Transparent rubber sleeves are wrapped around both sides of each deceleration section, extending along the extension direction of the deceleration section. The rubber sleeve includes two inclined sections and a parallel section arranged parallel to the deceleration section. The ends of the parallel section extend inwards towards the steel ruler, forming the inclined sections. The two inclined sections are symmetrically arranged at both ends of the parallel section.

[0030] As the counterweight falls from the mesh onto the uneven layer, the steel ruler strip is pulled out under the tension of the counterweight, and the roller rolls. When the parallel section passes through the channel opening, the parallel section presses against the inner circumference of the elastic ring, and the elastic ring is compressed and deformed. After the measurement is completed, the roller is driven to roll by the drive structure, so that the counterweight moves upward above the mesh.

[0031] Compared with existing technologies, the present invention provides a method for preparing the bottom rock surface of large-diameter rock-socketed piles using a rotary drilling full-section cutter bit. After the rotary drilling barrel is completed, a preparation drill barrel is replaced with a preparation drill barrel. Since the preparation drill barrel is formed by pre-cutting the bottom cutting teeth and roller cones of a rotary drilling barrel and welding a base plate equipped with cutter bits and roller cones to the bottom opening, it can be directly used with the drilling rig without changing the drilling rig. The uneven or stepped bottom of the hole can be fully prepared and smoothed using the roller cones and cutter bits, making the bottom of the hole flat. By repeatedly measuring the depth of the prepared rock surface in various directions and calculating the difference between the maximum and minimum depth data, if it is not within the set range, the preparation and smoothing operation is repeated to ensure that the difference is within the set range, forming a flat rock surface at the bottom of the borehole. This greatly reduces the probability of excessive sediment thickness at the bottom of the hole, effectively improves the quality of the pile body, and greatly saves the direct cost of defective pile treatment, resulting in significant social and economic benefits. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the construction method for repairing the bottom rock surface of a large-diameter rock-socketed pile using a rotary cutter bit with a full-section profile.

[0033] Figure 2 This is a construction diagram of step 2) provided by the present invention;

[0034] Figure 3 This is a bottom view schematic diagram of the dressing drill barrel provided by the present invention;

[0035] Figure 4 This is a three-dimensional schematic diagram of the toothed hob provided by the present invention;

[0036] Figure 5 This is a three-dimensional schematic diagram of the hobbing cutter holder provided by the present invention;

[0037] Figure 6 This is a partial schematic diagram of the cylinder provided by the present invention;

[0038] Figure 7 This is a partial schematic diagram of the organism provided by the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0040] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0041] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0042] Reference Figure 1-7 The image shows a preferred embodiment of the present invention.

[0043] The present invention provides a method for preparing the bottom rock surface of a large-diameter rock-socketed pile using a rotary cutter bit with a full-section cutter head, comprising the following construction steps:

[0044] 1) Mark the location of the rock-socketed piles at the construction site and install the casing 600 in the pile location; provide a drilling rig with a rotary drilling barrel connected to it; use the drilling rig to drive the rotary drilling barrel to core drill the core at the center of the casing 600 to form a borehole in the pile location; the bottom of the borehole is located in the rock layer 20 and forms the rock surface 21 to be repaired.

[0045] 2) Provide a dressing drill barrel; the dressing drill barrel includes a barrel 100 with a bottom opening, the bottom opening of the barrel 100 is provided with a base plate 200, the base plate 200 covers the bottom opening; the base plate 200 has a lower end face arranged downward and an upper end face arranged upward, the bottom of the barrel 100 is welded and fixed to the upper end face, the lower end face is provided with toothed hobs 310 and roller cone drill bits 400, the roller cone drill bits 400 are arranged at the center and both sides of the lower end face, and multiple toothed hobs 310 are staggered and spaced along the radial direction of the lower end face;

[0046] Replace the rotary drilling barrel with a trimming drilling barrel, and use the drilling rig to drive the trimming drilling barrel to trim and grind the rock surface 21 to be trimmed, forming a trimmed rock surface.

[0047] 3) Replace the trimming drill bit with a slag-removing drill bit. Use the drilling rig to drive the slag-removing drill bit to remove slag from the bottom of the borehole. Then, measure the depth of the trimmed rock surface in multiple directions multiple times to obtain trimmed rock surface depth data. The trimmed rock surface depth data includes the maximum depth data and the minimum depth data.

[0048] 4) When the difference between the maximum depth data and the minimum depth data is not less than 50mm, repeat steps 2) to 3) above until the difference between the maximum depth data and the minimum depth data is less than 50mm, forming a flat rock surface.

[0049] The above-mentioned construction method for repairing the bottom rock surface of a large-diameter rock-socketed pile using a rotary drilling full-section cutter bit involves replacing the rotary drilling barrel with a repairing drill barrel after the rotary drilling barrel has been excavated. Since the repairing drill barrel is formed by pre-cutting the bottom cutting teeth and roller cones of a rotary drilling barrel and then welding the bottom plate 200, which is equipped with toothed cutter 310 and roller cone bit 400, onto the bottom opening, it can be directly used with the drilling rig without changing the drilling rig. The roller cone bit 400 and toothed cutter 310 can be used to repair and grind the uneven or stepped bottom of the hole with the full section, making the bottom of the hole flat.

[0050] By repeatedly measuring the depth of the rock surface at various points and calculating the difference between the maximum and minimum depth data, if the difference is not within the set range, the drilling and smoothing operation is repeated to ensure that the difference is within the set range, thus forming a flat rock surface at the bottom of the borehole. This greatly reduces the probability of the sediment thickness at the bottom of the hole exceeding the standard, effectively improves the quality of the pile body, and greatly saves the direct cost of defective pile treatment, resulting in significant social and economic benefits.

[0051] The borehole includes an upper borehole located in the soil layer 10 and a lower borehole located in the rock layer 20, with the upper borehole situated above the lower borehole; the rotary drilling rig includes a small-diameter rig, a medium-diameter rig, and a large-diameter rig.

[0052] In step 1), after the upper hole is formed, the small-diameter cylinder is driven by a drilling rig to core drill towards the center of the upper hole to a set depth to form a primary hole. Then, the medium-diameter cylinder is driven by a drilling rig to core drill to a set depth, and the primary hole is enlarged to form a secondary hole. The secondary hole and the primary hole are arranged concentrically. Then, the large-diameter cylinder is driven by a drilling rig to core drill to a set depth, and the secondary hole is enlarged to form a lower hole. The lower hole and the secondary hole are arranged concentrically, and the upper hole and the lower hole are connected to form a borehole.

[0053] Thus, since rock stratum 20 is relatively hard, a staged drilling method is adopted for drilling rock stratum 20. Specifically, the small diameter cylinder is a 1600mm diameter cutting tooth drill cylinder for core sampling, drilling from the center of the pile, with each core sampling being about 1.2 to 1.5m, until the designed rock penetration depth is reached; the medium diameter cylinder is a 2000mm diameter cutting tooth drill cylinder and the large diameter cylinder is a 2400mm diameter cutting tooth drill cylinder, and staged drilling is adopted until the designed rock penetration drilling is completed.

[0054] In step 1), after the borehole is formed, the bottom of the borehole is cleaned. Thus, during the drilling process, mud is used for wall protection, and after drilling is completed, air-lift reverse circulation is used for cleaning, using high-quality mud to remove sediment from the bottom of the hole.

[0055] In step 1), after cleaning the bottom of the borehole, the depth of the rock surface 21 to be repaired is measured multiple times to obtain the depth data of the rock surface 21 to be repaired.

[0056] In step 2), based on the depth data of the rock surface 21 to be repaired, the drilling rig drives the trimming drill barrel to trim and smooth the rock surface 21. In this way, the maximum and minimum depth data of the rock surface 21 to be repaired are ensured. By comparing the obtained data with the borehole setting depth data, the depth of trimming drilling can be controlled in a planned manner.

[0057] In step 2), the toothed hob 310 is mounted and fixed on the hob bracket, which includes a base plate 300. The upper surface of the base plate 300 is fixed to the lower end face by welding. The two ends of the base plate 300 have mounting brackets 301 extending downwards, and the two mounting brackets 301 are arranged at intervals to form a mounting area 302.

[0058] A toothed hob 310 is arranged in the installation area 302. The toothed hob 310 includes a strip-shaped hob shaft 311 and a cylindrical hob cylinder 312. The two ends of the hob shaft 311 are fixedly connected to the mounting bracket 301 by bolts 305. The hob cylinder 312, which rolls around the hob shaft, is sleeved in the middle of the hob shaft 311. Multiple pointed grinding heads are embedded on the outer surface of the hob cylinder 312. The multiple grinding heads are evenly spaced on the hob cylinder 312.

[0059] Specifically, the grinding head 313 is made of diamond beads.

[0060] The toothed hob 310 is mounted on a bracket, and the bottom of the hole is continuously ground by the grinding head 313 during the drilling process to achieve a smooth bottom.

[0061] The horizontally rotating base plate 200 and the moving trajectory of the hob cylinder 312 form a hob grinding trajectory ring, while the moving trajectory of the roller cone drill bit 400 forms a roller cone grinding trajectory ring. Multiple hob grinding trajectory rings and multiple roller cone grinding trajectory rings completely cover the lower end face. This ensures complete coverage of the grinding trajectory.

[0062] The bottom frame of the mounting bracket 301 has two outwardly extending mounting heads 303, which are spaced apart to form a fixing area 304. The end of the hob shaft 311 passes through the fixing area 304 to form a through section.

[0063] The through section has a through hole, and the mounting head 303 has a mounting hole. The mounting hole and the through hole are aligned to form an anchoring channel. Bolts 305 are inserted into the anchoring channel to fix the through section to the mounting head 303. By using a cutter holder to fix both ends of the cutter shaft 311, and by using a grinding head to grind the rock layer 20 at the bottom of the hole during drilling, it is possible to achieve the goal of changing only the drill bit without changing the drilling machine, thereby improving work efficiency.

[0064] In step 2), the base plate 200 has multiple pressure relief holes 201 formed by cutting, which penetrate the base plate 200 from top to bottom. In this way, the pressure relief holes 201 are used to reduce pressure during drilling and improve the overall rock breaking drilling efficiency.

[0065] In step 2), multiple triangular steel frames 500 are welded and fixed to the upper end face. Each triangular steel frame 500 includes a horizontally arranged horizontal section 501 and a longitudinally arranged vertical section 502. The horizontal section 501 is welded and fixed to the upper end face, and the longitudinal section 502 is welded and fixed to the inner wall of the cylinder 100. In this way, the connection between the cylinder 100 and the bottom plate 200 is reinforced by the triangular steel frames 500. At the same time, the longitudinally arranged vertical section 502 and the horizontally arranged horizontal section 501 of the triangular steel frames 500 respectively fit the arrangement of the cylinder 100 and the bottom plate 200, ensuring the stability of the connection.

[0066] In step 4), the casing 600 has an upper ring 610 extending above the ground plane, and the top of the upper ring 610 has an annular end face 611; a steel mesh is laid on the annular end face 611, the mesh has multiple mesh holes, the multiple mesh holes are evenly spaced on the mesh, the mesh presses against the annular end face 611, and the mesh completely covers the annular end face 611.

[0067] The outer periphery of the net extends outward to form an outer ring located outside the annular end face 611, and the outer periphery of the outer ring extends towards the ground plane to form a lower ring; metal chains are connected to both sides of the net, one end of the metal chain is fixedly connected to the net, and the other end of the metal chain is fixedly sleeved on the lifting ring, which is then fixedly lifted to the top of the net.

[0068] When construction workers stand on the mesh to measure the depth of the uneven layer, the mesh presses against the annular end face 611, and the bottom of the lower extension ring presses against the ground plane. In this way, the pressure applied to the annular end face 611 is distributed by the lower extension ring, while the metal chain ensures that the mesh will not fall into the casing 600.

[0069] The depth of the uneven layer is measured using an elevation measuring instrument. The elevation measuring instrument includes a body 700, which has an annular inner cavity arranged around the center of the body 700.

[0070] The machine body 700 has a rollable roller inside its center and a drive structure inside the machine body 700 that can drive the roller to roll. The inner cavity has a steel ruler strip 701 wound into a disc shape. The steel ruler strip 701 is marked with a scale. The inner end of the steel ruler strip 701 is fixedly connected to the roller. The outer surface of the machine body 700 has a cavity opening that communicates with the inner cavity. The outer end of the steel ruler strip 701 extends outward to the outside of the cavity opening and is fixedly connected to a counterweight 720. The counterweight 720 is spherical. The width of the steel ruler strip 701 is smaller than the width of the cavity opening.

[0071] The body 700 has an enclosing wall that encloses and forms a cavity opening. An elastic ring 710 is provided on the enclosing wall and is arranged around the enclosing wall in a circumferential direction. The outer periphery of the elastic ring 710 is relatively fixed to the enclosing wall, and the inner periphery of the elastic ring 710 is enclosed to form a channel opening 702. The steel ruler strip 701 has multiple deceleration sections that are evenly spaced along the length of the steel ruler strip 701. The outer periphery of each deceleration section is covered with a transparent rubber sleeve 730, which extends along the extension direction of the deceleration section. The rubber sleeve 730 includes two inclined sections 732 and a parallel section 731 arranged parallel to the deceleration section. The end of the parallel section 731 extends inward toward the steel ruler strip 701 at an incline to form the inclined section 732. The two inclined sections 732 are symmetrically arranged at both ends of the parallel section 731.

[0072] As the counterweight 720 falls from the mesh onto the uneven layer, the steel ruler strip 701 is pulled out under the tension of the counterweight 720, causing the roller to roll. When the parallel section 731 passes through the channel opening 702, the parallel section 731 presses against the inner circumference of the elastic ring 710, causing the elastic ring 710 to compress and deform. After the measurement is completed, the roller is driven to roll through the drive structure, causing the counterweight 720 to move upward above the mesh.

[0073] In this way, the accuracy of the measurement is ensured by using gravity to fall, while the design of the deceleration section effectively avoids the counterweight 720 falling too fast, which would result in a large impact force that would damage the rock surface. At the same time, the design of the inclined section 732 serves as a transition, and the design of the parallel section 731 effectively achieves friction deceleration.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a full-section rotary cutter drill bit, characterized in that... The construction steps include the following: 1) Mark out the pile positions of the rock-socketed piles at the construction site and install casings in the pile positions; provide a drilling rig, which is movably connected to a rotary drilling rig, and use the drilling rig to drive the rotary drilling rig to core drill in the center of the casing to form a borehole in the pile position; the bottom of the borehole is located in the rock strata and forms a rock surface to be repaired. 2) Provide a dressing drill barrel; the dressing drill barrel includes a barrel with a bottom opening, the bottom opening of the barrel is provided with a bottom plate, the bottom plate covers the bottom opening; the bottom plate has a lower end face arranged downward and an upper end face arranged upward, the bottom of the barrel is welded and fixed to the upper end face, the lower end face is provided with toothed hobs and roller cone drill bits, the roller cone drill bits are arranged at the center and both sides of the lower end face, and multiple toothed hobs are staggered and spaced along the radial direction of the lower end face; The rotary drilling barrel is replaced with a trimming drilling barrel, and the trimming drilling barrel is driven by the drilling rig to trim and grind the rock surface to be trimmed, forming a trimmed rock surface. 3) Replace the trimming drill bit with a slag-removing drill bit, and use the drilling rig to drive the slag-removing drill bit to remove slag from the bottom of the borehole. Then, measure the depth of the trimmed rock surface in multiple directions multiple times to obtain trimmed rock surface depth data. The trimmed rock surface depth data includes the maximum depth data and the minimum depth data. 4) When the difference between the maximum depth data and the minimum depth data is not less than 50mm, repeat steps 2) to 3) above until the difference between the maximum depth data and the minimum depth data is less than 50mm, forming a flat rock surface; In step 2), the toothed hob is mounted and fixed on the hob bracket, which includes a base plate. The upper surface of the base plate is fixed to the lower end face by welding. The two ends of the base plate have mounting brackets that extend downwards, and the two mounting brackets are arranged at intervals to form an installation area. A toothed hob is arranged in the installation area. The toothed hob includes a strip-shaped hob shaft and a cylindrical hob tube. The two ends of the hob shaft are fixedly connected to the mounting bracket by bolts. The hob tube that rolls around the hob shaft is sleeved in the middle of the hob shaft. Multiple pointed grinding heads are embedded on the outer surface of the hob tube. The multiple grinding heads are evenly spaced on the hob tube. The base plate is rotated horizontally, and the movement trajectory of the hob barrel forms a hob grinding trajectory ring, and the movement trajectory of the roller cone drill bit forms a roller cone grinding trajectory ring. Multiple hob grinding trajectory rings and multiple roller cone grinding trajectory rings completely cover the lower end face. The bottom frame of the mounting bracket has two outwardly extending mounting heads, which are spaced apart to form a fixed area. The end of the hob shaft passes through the fixed area to form a through section. The through section is provided with a through hole, and the mounting head is provided with a mounting hole. The mounting hole and the through hole are aligned to form an anchoring channel. The bolt is inserted into the anchoring channel to fix the through section and the mounting head together.

2. The method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a rotary cutter bit as described in claim 1, characterized in that... The borehole includes an upper borehole located in the soil layer and a lower borehole located in the rock layer, with the upper borehole situated above the lower borehole; the rotary drilling rig includes a small-diameter rig, a medium-diameter rig, and a large-diameter rig; In step 1), after the upper hole is formed, the small-diameter cylinder is driven by a drilling rig to drill towards the center of the upper hole to a set depth to form a primary hole. Then, a drilling rig is used to drive a core drill to a set depth, and the primary hole is enlarged to form a secondary hole. The secondary hole and the primary hole are arranged concentrically. Then, a drilling rig is used to drive a large-diameter cylinder for coring and drilling to a set depth. The secondary hole is enlarged to form a lower hole. The lower hole and the secondary hole are arranged concentrically. The upper hole and the lower hole are connected to form the borehole.

3. The method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a rotary cutter bit as described in claim 2, characterized in that... In step 1), after the borehole is formed, the bottom of the borehole is cleaned.

4. The method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a rotary cutter bit as described in claim 3, characterized in that... In step 1), after cleaning the bottom of the borehole, the depth of the rock surface to be repaired is measured multiple times to obtain the depth data of the rock surface to be repaired. In step 2), based on the depth data of the rock surface to be repaired, the drilling rig drives the trimming drill barrel to trim and grind the rock surface to be repaired.

5. The method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a rotary cutter bit as described in claim 1, characterized in that... In step 2), the base plate has multiple pressure relief holes formed by cutting, and the pressure relief holes penetrate the base plate from top to bottom.

6. The method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a rotary cutter bit as described in claim 5, characterized in that... In step 2), multiple triangular steel frames are welded and fixed on the upper end face. The triangular steel frames include horizontally arranged horizontal sections and longitudinally arranged vertical sections. The horizontal sections are welded and fixed on the upper end face, and the longitudinal sections are welded and fixed on the inner wall of the cylinder.

7. The method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a rotary cutter bit as described in any one of claims 1 to 6, characterized in that... In step 4), the casing has an upper ring extending above the ground plane, and the top of the upper ring has an annular end face; a steel mesh is laid on the annular end face, the mesh has multiple mesh holes, the multiple mesh holes are evenly spaced on the mesh, the mesh presses against the annular end face, and the mesh completely covers the annular end face; The outer periphery of the net extends outward to form an outer ring located outside the annular end face, and the outer periphery of the outer ring extends towards the ground plane to form a lower ring; metal chains are respectively connected to both sides of the net, one end of the metal chain is fixedly connected to the net, and the other end of the metal chain is fixedly sleeved on a lifting ring, which is fixedly lifted to the top of the net; When construction workers stand on the mesh to measure the depth of the uneven layer, the mesh presses against the annular end face, and the bottom of the lower extension ring presses against the ground plane.

8. The method for preparing the bottom rock surface of a large-diameter rock-socketed pile hole using a rotary cutter bit as described in claim 7, characterized in that... The depth of the uneven layer is measured using an elevation measuring instrument, which includes a body and an annular inner cavity arranged around the center of the body. The machine body has a rollable roller at its center, and a drive structure that can drive the roller to roll is provided inside the machine body. A steel ruler strip wound into a disc shape is provided inside the inner cavity. The steel ruler strip is marked with a scale. The inner end of the steel ruler strip is fixedly connected to the roller. The outer surface of the machine body has a cavity opening that communicates with the inner cavity. The outer end of the steel ruler strip extends outward to the outside of the cavity opening and is fixedly connected to a counterweight. The counterweight is spherical. The width of the steel ruler strip is smaller than the width of the cavity opening. The body has an enclosing wall that encloses and forms the cavity opening. An elastic ring is provided on the enclosing wall, and the elastic ring is arranged around the enclosing wall along its circumferential direction. The outer periphery of the elastic ring is relatively fixed to the enclosing wall, and the inner periphery of the elastic ring encloses and forms a channel opening. The steel ruler has multiple deceleration sections, which are evenly spaced along the length of the steel ruler. Transparent rubber sleeves are wrapped around both sides of each deceleration section, extending along the extension direction of the deceleration section. The rubber sleeve includes two inclined sections and a parallel section arranged parallel to the deceleration section. The ends of the parallel section extend inwards towards the steel ruler, forming the inclined sections. The two inclined sections are symmetrically arranged at both ends of the parallel section. As the counterweight falls from the mesh onto the uneven layer, the steel ruler strip is pulled out under the tension of the counterweight, and the roller rolls. When the parallel section passes through the channel opening, the parallel section presses against the inner circumference of the elastic ring, and the elastic ring is compressed and deformed. After the measurement is completed, the roller is driven to roll by the drive structure, so that the counterweight moves upward above the mesh.

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