A verticality control device for a long and large diameter rotary drilling bored pile construction steel casing

Abstract

The present application relates to the pile engineering construction technical field, specifically disclose a long diameter rotary drilling bored pile construction is with steel casing verticality control device, including setting on the upper surface of the geological layer positioning ring, from the center of the positioning ring is drilled in the geological layer installation hole, a plurality of stacked pipe bodies are arranged in the installation hole, a plurality of pipe bodies are combined to form an outer sleeve, a steel casing is arranged in the outer sleeve, a plurality of positioning adjusting devices are arranged between each pipe body and the steel casing, and the positioning adjusting devices are used to keep the steel casing in a vertical state. By setting the outer sleeve combined by a plurality of pipe bodies, the steel casing is placed inside the outer sleeve, the outer sleeve can effectively resist the active earth pressure of the external soil body, even if the verticality of the outer sleeve itself has a deviation, the pressure will not be transmitted to the internal steel casing, when adjusting the verticality of the steel casing, the adjusting mechanism does not need to overcome the huge active earth pressure, greatly reducing the adjusting difficulty.

Description

Technical Field

[0001] This invention relates to the field of pile engineering construction technology, and in particular to a verticality control device for steel casing used in the construction of long-diameter rotary cast-in-place piles. Background Technology

[0002] In the construction of long-diameter rotary bored piles, the lowering and positioning of the steel casing is a crucial step in ensuring the quality of the borehole. With increasingly stringent engineering requirements, the verticality deviation of the steel casing must be controlled within an extremely small range. In existing technologies, the steel casing is typically placed directly into a pre-drilled hole, and construction workers often rely on ground-based guide frames or external support equipment to adjust its verticality. Due to the complex stress distribution within the geological strata, when the steel casing is lowered to a certain depth, the surrounding soil exerts active earth pressure on it. This active earth pressure is not only enormous but also unevenly distributed, requiring construction workers to expend considerable mechanical force to overcome the squeezing and obstruction of the active earth pressure when adjusting the casing's verticality. This significantly increases the construction difficulty and equipment load, and is also highly susceptible to deformation or localized jamming of the steel casing, making precise verticality control exceptionally difficult. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a verticality control device for steel casing used in the construction of long-diameter rotary bored piles.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A verticality control device for steel casing used in the construction of long-diameter rotary bored piles includes a positioning ring set on the upper surface of the geological layer, an installation hole drilled from the center of the positioning ring in the geological layer, multiple stacked pipes are arranged in the installation hole, the multiple pipes are combined to form an outer casing, a steel casing is installed inside the outer casing, and multiple positioning adjustment devices are provided between each pipe and the steel casing, the positioning adjustment devices are used to keep the steel casing in a vertical state.

[0005] Preferably, the positioning ring is fixed to the upper surface of the geological layer by multiple anchor bolts.

[0006] Preferably, the anchor rod is inclined along the direction from the center to the edge of the positioning ring.

[0007] Preferably, the positioning adjustment device includes a fixed base, which is spherically hinged to the inner wall of the tube by a ball. A socket is provided on one side of the fixed base, and a plug rod is slidably connected in the socket. An arc-shaped rod is fixedly connected to one end of the plug rod. Chamfers are provided at the upper and lower corners of the inner arc surface of the arc-shaped rod. The lower end of the steel casing is a conical surface, which is provided in correspondence with the chamfers. The arc-shaped rods of two adjacent positioning adjustment devices are fixedly connected by corrugated steel strips.

[0008] Preferably, the tube body is provided with a relief groove, and the insertion rod can pass through the fixing seat and the ball and extend into the relief groove.

[0009] Preferably, a power hammer is installed inside the steel casing. The power hammer is hoisted into the steel casing by a lifting rod. The steel casing has multiple clearance holes on its bore wall, through which the power hammer can pass and strike the arc-shaped rod.

[0010] The beneficial effects of this invention are as follows: By setting an outer protective pipe composed of multiple pipe bodies, and placing the steel casing inside the outer protective pipe, the outer protective pipe can effectively resist the active earth pressure from the external soil. Even if there is a deviation in the verticality of the outer protective pipe itself, this pressure will not be transmitted to the internal steel casing. When adjusting the verticality of the steel casing, the positioning and adjustment device does not need to overcome the huge active earth pressure, greatly reducing the difficulty of adjustment. At the same time, setting the outer protective pipe in the form of multiple short pipe bodies stacked together can significantly reduce the friction between each pipe body and the wall of the installation hole during the lowering process, making the lowering operation smoother and less labor-intensive. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the basic structure of the present invention; Figure 2 This is a cross-sectional view of the basic structure of the present invention; Figure 3 This is a diagram showing the connection structure between the outer protective pipe and the steel casing; Figure 4 This is a diagram showing the connection structure of the power hammer, outer protective pipe, and steel casing. Figure 5 yes Figure 4 Enlarged view of point A. Detailed Implementation

[0012] 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.

[0013] like Figures 1-4 As shown in the figure, this embodiment provides a verticality control device for steel casing used in the construction of long-diameter rotary bored piles. It includes a positioning ring 200 disposed on the upper surface of a geological layer 100, which is fixed to the upper surface of the geological layer 100 by multiple anchor rods 900. The anchor rods 900 are inclined along the direction from the center to the edge of the positioning ring 200. This effectively prevents the positioning ring 200 from horizontal displacement or overturning during subsequent construction, providing a reference for subsequent construction.

[0014] An installation hole is drilled from the center of the positioning ring 200 into the geological layer 100. The drilling method for the installation hole is existing technology and will not be described in detail here. Multiple stacked tubes 300 are arranged inside the installation hole. The multiple tubes 300 are stacked together to form an outer protective tube. The segmented structure of the outer protective tube can greatly reduce the lowering resistance.

[0015] The outer protective tube contains a steel casing 400. Multiple positioning and adjusting devices are installed between each tube body 300 and the steel casing 400 to ensure the steel casing 400 remains vertical. These devices are evenly distributed circumferentially on the inner wall of each tube body 300. Each positioning and adjusting device includes a fixed base 2, which is ball-hinged to the inner wall of the tube body 300 via a ball 1. This ball-hinged connection is existing technology and will not be described further. This allows the fixed base 2 to swing at a certain angle.

[0016] The fixed base 2 has an insertion hole on one side, and the insertion rod 3 is slidably connected in the insertion hole. The tube body 300 has a relief groove 301. One end of the insertion rod 3 can pass through the fixed base 2 and the ball 1 and extend into the relief groove 301.

[0017] The other end of the insertion rod 3 is fixedly connected to the arc rod 4. The upper and lower corners of the inner arc surface of the arc rod 4 are provided with chamfers. The lower end of the steel casing 400 is a conical surface, which is provided in correspondence with the chamfers. The arc rods 4 of two adjacent positioning and adjusting devices are fixedly connected by corrugated steel strips 5, so that multiple arc rods 4 form an overall ring structure that can move independently radially and deform collaboratively in the circumferential direction.

[0018] The present invention is provided with an outer protective pipe and a steel casing 400. The outer protective pipe resists the soil pressure of the external soil. Even if there is a deviation in the verticality of the outer protective pipe itself, it will not affect the adjustment of the verticality of the steel casing 400. Moreover, when adjusting the verticality of the steel casing 400, the external soil pressure will not affect the steel casing 400, which makes it convenient to control the verticality of the steel casing 400.

[0019] In this invention, the outer protective tube is composed of multiple tube bodies 300. This significantly reduces the friction between the tube body 300 and the hole wall when it is inserted into the mounting hole, facilitating placement. Furthermore, since the positioning adjustment device is located on the inner wall of the tube body 300, even slight tilting or displacement of a single tube body 300 does not affect the adjustment of the verticality of the steel casing 400. This avoids the difficulty of overcoming soil pressure to adjust the steel casing 400 in existing technologies.

[0020] In this embodiment, the positioning adjustment device has a simple adaptive function. During the lowering of the steel casing 400, when the conical surface at the lower end of the steel casing 400 contacts and presses against the chamfered edge of the arc-shaped rod 4, a component force pointing towards the center is generated due to the effect of the inclined surface, pushing the arc-shaped rod 4 and the insert rod 3 towards the clearance groove 301. As the steel casing 400 continues to lower, the multiple arc-shaped rods 4 will uniformly retract outwards under the pressure of their conical surfaces, simultaneously generating a centripetal reaction force on the steel casing 400, thereby achieving automatic centering and initial verticality correction of the lower part of the steel casing 400. In this way, the steel casing 400 is initially adaptively positioned using multiple arc-shaped rods 4.

[0021] Then, the steel casing 400 is adjusted from the upper surface of the geological layer 100, making it easy to control its verticality. If the steel casing 400 cannot be kept vertical from the upper surface of the geological layer 100, this embodiment provides multiple clearance holes 401 on the borehole wall of the steel casing 400. A power hammer 500 is lowered into the steel casing 400 via a lifting rod 600. The power hammer 500 is existing technology and will not be described in detail here. The power hammer 500 is moved to the corresponding height and angle that need to be adjusted, so that the hammer head of the power hammer 500 passes through the clearance hole 401 on the steel casing 400. Then, the power hammer 500 is started to precisely strike the inner side of the target arc-shaped rod 4. By applying different impact forces to the arc-shaped rod 4 at different positions and heights, the local radial position of the steel casing 400 can be precisely adjusted. After the adjustment is completed, concrete grout is injected into the steel casing 400 and the outer casing, and the concrete grout forms an integral structure between the steel casing 400 and the outer casing. Finally, conventional construction steps such as pouring concrete for the cast-in-place piles can be carried out.

[0022] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A device for controlling the verticality of a steel casing used in the construction of long-diameter rotary bored piles, characterized in that: The system includes a positioning ring (200) set on the upper surface of the geological layer (100), an installation hole is drilled in the geological layer (100) from the center of the positioning ring (200), a plurality of stacked tubes (300) are provided in the installation hole, the plurality of tubes (300) are combined to form an outer protective tube, a steel casing (400) is provided inside the outer protective tube, and a plurality of positioning adjustment devices are provided between each of the tubes (300) and the steel casing (400), the positioning adjustment devices are used to keep the steel casing (400) in a vertical state.

2. The verticality control device for steel casing used in the construction of long-diameter rotary bored piles according to claim 1, characterized in that: The positioning ring (200) is fixed to the upper surface of the geological layer (100) by multiple anchor rods (900).

3. The verticality control device for steel casing used in the construction of long-diameter rotary bored piles according to claim 2, characterized in that: The anchor rod (900) is inclined along the direction from the center to the edge of the positioning ring (200).

4. The verticality control device for steel casing used in the construction of long-diameter rotary bored piles according to claim 1, characterized in that: The positioning adjustment device includes a fixed seat (2), which is spherically hinged to the inner wall of the tube body (300) by a ball (1). The fixed seat (2) has an insertion hole on one side, and a plug rod (3) is slidably connected in the insertion hole. One end of the plug rod (3) is fixedly connected to an arc rod (4). The upper and lower corners of the inner arc surface of the arc rod (4) are provided with chamfers. The lower end of the steel casing (400) is a conical surface, and the conical surface is provided in correspondence with the chamfers. The arc rods (4) of two adjacent positioning adjustment devices are fixedly connected by corrugated steel strips (5).

5. The verticality control device for steel casing used in the construction of long-diameter rotary bored piles according to claim 4, characterized in that: The tube body (300) is provided with a relief groove (301), and the insertion rod (3) can pass through the fixed seat (2) and the ball (1) and extend into the relief groove (301).

6. The verticality control device for steel casing used in the construction of long-diameter rotary bored piles according to claim 5, characterized in that: A power hammer (500) is installed inside the steel casing (400). The power hammer (500) is hoisted into the steel casing (400) by a lifting rod (600). The steel casing (400) has multiple clearance holes (401) on its bore wall. The power hammer (500) can pass through the clearance holes (401) and strike the arc-shaped rod (4).

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