Device and method for arranging helical micro-rib in concrete 3D printing process

Abstract

The application relates to the technical field of digital construction, and particularly discloses a device and method for arranging spiral micro steel bars in a concrete 3D printing process, which comprises a barrel arranged at the bottom of a nozzle and matched with the nozzle in rotation around the nozzle axis, a spiral steel bar arranging assembly arranged outside the barrel and used for guiding the micro steel bars into the barrel, and a steel bar conveying assembly arranged outside the 3D printing device and used for conveying the micro steel bars into the spiral steel bar arranging assembly; an output cavity coaxially communicated with the nozzle is arranged in the barrel; the spiral steel bar arranging assembly comprises a spiral groove wheel arranged outside the barrel and provided with a spiral groove on the surface, and a steel bar outlet pipe with one end communicated with the spiral groove and the other end communicated with the output cavity; the spiral groove wheel is matched with the barrel in rotation; and the lead of the spiral groove is matched with the extrusion speed of the 3D printing device. The micro steel bars can be effectively arranged in a spiral mode and synchronously formed with the concrete strips, the bonding effect of the micro steel bars and the concrete is strengthened, and the mechanical properties and durability of the 3D printed concrete component are improved.

Description

Technical Field

[0001] This invention relates to the field of digital construction technology, and more specifically, to an apparatus and method for arranging spiral micro-ribs during the 3D printing of concrete. Background Technology

[0002] Concrete 3D printing technology has been widely used in the construction industry due to its advantages of automation, moldlessness, and high efficiency. However, printed concrete has core problems such as weak interlayer bonding, low tensile and flexural strength, and high brittleness. Traditional reinforcement methods (such as pre-embedded micro-reinforcements and post-installed rebar) are difficult to adapt to the continuous and dynamic extrusion process of 3D printing, and are prone to problems such as delayed reinforcement placement and poor bonding between micro-reinforcements and concrete. While linear micro-reinforcements can toughen the concrete to a certain extent, their contact area with the concrete is limited, resulting in poor bonding and anchoring effects, and failing to fully exert the toughening effect of micro-reinforcements.

[0003] Double-helix microribs can increase the contact area with concrete through a three-dimensional winding structure, forming a synergistic effect of mechanical interlocking force and chemical bonding force, thereby improving interfacial bond strength. At the same time, the double-helix structure can form a three-dimensional reinforcing network inside the concrete, significantly improving the toughness and tensile and shear properties of the concrete. However, there is currently a lack of dedicated spiral reinforcement devices adapted to continuous extrusion of concrete in 3D printing, and the synchronous operation control of reinforcement placement and printing, as well as the bonding mechanism between the spiral microribs and concrete, have not yet formed a systematic solution, which restricts the engineering application of this technology. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a device and method for arranging spiral micro-ribs in the process of concrete 3D printing; it can effectively make the micro-ribs spiral and synchronously form with the concrete strips, solve the problem of synchronous operation of rib arrangement and printing, strengthen the bonding effect between micro-ribs and concrete, and improve the mechanical properties and durability of 3D printed concrete components.

[0005] The solution adopted by this invention to solve the technical problem is: on the one hand: A device for arranging spiral microribs during concrete 3D printing includes a cylinder disposed at the bottom of a nozzle and rotating around the nozzle axis with the nozzle, a spiral rib-arranging assembly installed on the outside of the cylinder and guiding the microribs into the cylinder, and a rib-feeding assembly installed on the outside of the 3D printing device and used to deliver the microribs into the spiral rib-arranging assembly; the cylinder is provided with an output cavity coaxially connected to the nozzle. The spiral reinforcement assembly includes a spiral groove wheel disposed on the outside of the cylinder and having spiral grooves on its surface, and a reinforcement tube with one end connected to the spiral groove and the other end connected to the output cavity; the spiral groove wheel rotates in conjunction with the reinforcement feeding assembly; the lead of the spiral groove is matched with the extrusion speed of the 3D printing device.

[0006] In some possible implementations, the spiral reinforcement assembly further includes a transmission component disposed on the side of the spiral groove wheel away from the reinforcement outlet pipe and used for secondary transmission of the micro-reinforcements conveyed by the reinforcement feeding assembly.

[0007] In some possible implementations, a rotation drive unit for controlling the rotation of the cylinder is provided on the outside of the 3D printing device; A rotary drive device is provided on the outside of the cylinder to control the rotation of the spiral groove wheel around its axis; the pitch of the spiral groove is P, the extrusion speed of the 3D printing device is v; the angular velocity of the rotary drive device is ω, P=v / ω.

[0008] In some possible implementations, the spiral groove is an equidistant spiral groove with a pitch of P = 10~50mm, the diameter of the microrib is 0.5~1.5mm, and the width and depth of the spiral groove are adapted to the diameter of the microrib; the rotational speed of the cylinder is 0~30r / min.

[0009] In some possible implementations, the micro-reinforcement is any one of basalt fiber reinforcement, stainless steel micro-reinforcement, or carbon fiber reinforcement.

[0010] In some possible implementations, the rib feeding assembly includes a support disposed outside the barrel in the 3D printing device, a rib storage plate mounted on the support, a rib feeding wheel assembly mounted at the bottom of the support, and a tension monitoring assembly mounted on the support for monitoring the conveying tension of the microribs.

[0011] In some possible implementations, the transmission assembly includes a transmission roller assembly disposed outside the spiral groove wheel for conveying microribs into the spiral groove, and a guide sleeve disposed away from the spiral groove wheel for guiding the microribs.

[0012] In some possible implementations, a housing is also included, which is fitted over the outside of the cylinder and forms an installation cavity with the cylinder, the spiral reinforcement assembly is located inside the installation cavity, and the guide sleeve is disposed on the outside of the housing.

[0013] In some possible implementations, the spiral grooved wheel is mounted on a transfer roller assembly via a mounting bracket; the transfer roller assembly includes a mounting plate and rollers mounted on the mounting plate for conveying microribs; the mounting plate and the housing slide in axial engagement along the nozzle.

[0014] In some possible implementations, the spiral reinforcement assembly is in two sets, and the reinforcement storage plate, reinforcement feeding wheel set, and tension monitoring assembly are in two sets and are arranged in a one-to-one correspondence with the spiral reinforcement assembly; the two sets of spiral reinforcement assemblies are arranged symmetrically along the axis of the nozzle.

[0015] on the other hand: This invention also provides a method for arranging spiral microribs during concrete 3D printing, based on the aforementioned device for arranging spiral microribs during concrete 3D printing; specifically including the following steps: Set the pitch P of the spiral grooved wheel and the extrusion speed v of the 3D printing device, calculate the angular velocity ω=v / P of the rotary drive device, and obtain the rotational speed n of the spiral grooved wheel about its axis. Start the 3D printing device to extrude concrete, while controlling the spiral groove wheel to rotate around its axis at a speed n and the cylinder to rotate around the axis of the nozzle; The feed assembly feeds the micro-reinforcement into the spiral groove wheel. The micro-reinforcement enters the output chamber through the spiral reinforcement assembly and is spirally embedded in the concrete strip formed by extrusion. After printing, the concrete component is cured according to standard procedures, so that the spiral micro-reinforcements form a synergistic bond with the concrete matrix through mechanical interlocking and chemical adhesion.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention achieves continuous molding of spiral micro-ribs and 3D-printed concrete strips through synchronous control. The spiral micro-ribs significantly improve the toughness, interlayer bond strength, and overall mechanical properties of 3D-printed concrete through mechanical interlocking force, chemical bonding force, and circumferential constraint. This invention is adapted to the continuous and automated requirements of concrete 3D printing, solves the problems of poor bonding and synchronization difficulties in traditional reinforcement methods, and is suitable for toughening and strengthening various 3D-printed concrete components. This invention achieves the synchronous molding of micro-reinforcement in a spiral shape with the concrete strip formed by 3D printing through the rotational cooperation of the cylinder and nozzle, and the cooperation of the spiral reinforcement assembly and the reinforcement feeding assembly set on the outside of the cylinder. This effectively solves the problem of synchronous operation of reinforcement and printing in the prior art, strengthens the bonding between micro-reinforcement and concrete, and improves the mechanical properties and durability of 3D printed concrete components.

[0017] This invention effectively ensures that the micro-reinforcements can be arranged in a spiral pattern on the concrete through the cooperation of the reinforcing tube and the spiral groove wheel. This invention matches the lead of the spiral groove with the extrusion speed of the printed concrete strip, so that the conveying speed of the spiral reinforcement assembly for the micro-reinforcement is consistent with the extrusion speed of the concrete, achieving synchronous and same-speed extrusion molding of the micro-reinforcement and the concrete strip, ensuring the positional accuracy and structural continuity of the micro-reinforcement 35 within the concrete strip; and distributing the spiral micro-reinforcement in the core stress area of ​​the lower middle part of the concrete strip, thereby enabling the micro-reinforcement to effectively share the tensile stress. Attached Figure Description

[0018] Figure 1This is a schematic diagram of the structure of the present invention installed on a 3D printing device; Figure 2 This is a schematic diagram of the structure of the cylinder, nozzle, outer shell, and spiral reinforcement assembly in this invention; Figure 3 This is a schematic diagram of the spiral reinforcement assembly in this invention; Figure 4 This is a schematic diagram of the structure of the concrete strip prepared using the present invention; in: 1. 3D printing equipment; 11. Nozzle; 2. Cylinder body; 3. Spiral reinforcement assembly; 31. Spiral grooved wheel; 32. Rib tube; 33. Transfer roller assembly; 34. Guide sleeve; 35. Micro-rib; 4. Reinforcing bar assembly; 41. Support frame; 42. Rebar storage plate; 43. Rebar feeding wheel assembly; 44. Tension monitoring component; 5. Outer casing; 10. Concrete strips. Detailed Implementation

[0019] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "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 direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "a" or "one," etc., do not indicate a quantity limitation, but rather indicate the existence of at least one. In the implementation of this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more. For example, multiple positioning posts refer to two or more positioning posts. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0020] The present invention will now be described in detail.

[0021] like Figures 1-4 As shown: A device for arranging spiral micro-ribs 35 during concrete 3D printing includes a cylinder 2 disposed at the bottom of a nozzle 11 and rotatably coupled with the nozzle 11 around its axis, a spiral rib arrangement assembly 3 installed on the outside of the cylinder 2 and guiding the micro-ribs 35 into the cylinder 2, and a rib delivery assembly 4 installed on the outside of a 3D printing device 1 and used to deliver the micro-ribs 35 into the spiral rib arrangement assembly 3; the cylinder 2 is provided with an output cavity coaxially connected to the nozzle 11. The spiral reinforcement assembly 3 includes a spiral groove wheel 31 disposed on the outside of the cylinder 2 and having a spiral groove on its surface, and a reinforcement outlet tube 32 with one end connected to the spiral groove and the other end connected to the output cavity; the spiral groove wheel 31 rotates with the cylinder 2; the lead of the spiral groove matches the extrusion speed of the 3D printing device 1 to ensure that the micro-reinforcement 35 forms a continuous spiral line during the concrete extrusion process, thereby distributing the spiral micro-reinforcement 35 in the middle and lower core stress area of ​​the concrete strip 10.

[0022] In some possible implementations, the spiral reinforcement assembly 3 further includes a transmission component disposed on the side of the spiral groove wheel 31 away from the reinforcement tube 32 and used for secondary transmission of the micro-reinforcement 35 conveyed by the reinforcement feeding assembly 4.

[0023] The spiral groove wheel 31 is made of hard alloy or stainless steel and has a surface machined with equal pitch spiral grooves. The transmission component is used to transport the micro-ribs 35 conveyed by the rib delivery component 4 to the spiral groove. The micro-ribs 35 move along the spiral groove and form a spiral structure. Then they enter the rib outlet pipe 32 and enter the output chamber through the rib outlet pipe 32, and are formed synchronously with the concrete strip 10 formed by the nozzle 11. Since the cylinder 2 and the nozzle 11 are rotatably coupled, the micro-ribs 35 output through the rib outlet pipe 32 will spirally wrap around the concrete strip 10. In some possible implementations, a rotation drive unit for controlling the rotation of the cylinder 2 is provided on the outside of the 3D printing device 1, thereby effectively controlling the rotational engagement between the cylinder 2 and the nozzle 11; under the drive of the cylinder 2, the spiral groove wheel can rotate around the axis of the nozzle 11. The pitch of the spiral groove is P, the extrusion speed of the 3D printing device 1 is v, and the angular velocity of the rotary drive device is ω, where P = v / ω.

[0024] Specifically, the rotary drive unit consists of a servo motor and a planetary reducer. The servo motor outputs a speed range of 0~30r / min, which can achieve stepless speed regulation. It is used to drive the cylinder 2 to rotate, thereby driving the spiral groove wheel 31 to rotate, and effectively ensuring the accuracy and stability of its rotation. A rotary drive device is provided on the outer side of the cylinder 2 to control the rotation of the helical groove wheel around its axis; the rotary drive device can change the pitch of the helical microribs, thereby adjusting the reinforcement density according to different structural requirements.

[0025] In some possible implementations, the spiral groove is an equidistant spiral groove with a pitch of P = 10~50mm, the diameter of the micro-rib 35 is 0.5~1.5mm, and the width and depth of the spiral groove are adapted to the diameter of the micro-rib 35; the rotational speed of the cylinder 2 is 0~30r / min.

[0026] In some possible implementations, the micro-ribs 35 are any one of basalt fiber ribs, stainless steel ribs, and carbon fiber ribs.

[0027] In some possible implementations, the feed assembly 4 includes a bracket 41 disposed outside the barrel in the 3D printing device 1, a feed storage plate 42 mounted on the bracket 41, a feed wheel assembly 43 mounted on the bottom of the bracket 41, and a tension monitoring assembly 44 mounted on the bracket 41 for monitoring the feed tension of the micro-ribs 35.

[0028] The rib storage tray 42 is used to store the rolled micro-ribs 35. The rib storage tray 42 is equipped with a damper to prevent the micro-ribs 35 from being unwound too quickly or too slowly. The rib feeding wheel group 43 adopts a double wheel pressure structure and the wheel surface is processed with anti-slip texture. It is driven by a stepper motor. The rib feeding speed is linked with the rotation speed of the spiral groove wheel 31 and the printing extrusion speed for continuous conveying of micro-ribs 35. The tension monitoring component 44 is a tension sensor used to detect the conveying tension of the microrib 35 in real time. When the conveying tension exceeds the set range, the speed of the feed wheel will be adjusted to achieve closed-loop control of the conveying tension, so as to ensure the stability and continuity of the microrib 35 material during the conveying process.

[0029] In some possible implementations, the transmission assembly includes a transmission roller assembly 33 disposed outside the spiral groove wheel 31 for conveying the microribs 35 into the spiral groove, and a guide sleeve 34 disposed away from the spiral groove wheel 31 and for guiding the microribs 35.

[0030] The guide sleeve 34 is made of wear-resistant ceramic or nylon material. One end is connected to the outlet of the spiral groove of the spiral groove wheel 31, and the other end extends into the interior of the print head nozzle 11. The length is 5~20mm. This effectively prevents the micro ribs 35 from shifting during the extrusion process, ensuring that the micro ribs 35 maintain a stable direction when entering, and ensuring the accuracy of the spiral trajectory.

[0031] In some possible implementations, a housing 5 is also included, which is fitted around the outside of the cylinder 2 and forms an installation cavity with the cylinder 2, the spiral reinforcement assembly 3 is located inside the installation cavity, and the guide sleeve 34 is disposed on the outside of the housing 5.

[0032] In some possible implementations, the spiral grooved wheel is mounted on the transfer roller assembly 33 by a mounting bracket; the transfer roller assembly 33 includes a mounting plate for the mounting bracket and rollers mounted on the mounting plate for conveying the microribs 35; the mounting plate is slidably engaged with the housing 5 along the axial direction of the nozzle 11; the mounting plate is mounted on the inner side of the housing; the mounting bracket is located on the side of the mounting plate away from the housing 5.

[0033] There are two sets of rollers, and a gap is formed between the two sets of rollers to allow the micro-ribs 35 to pass through; In some possible implementations, the spiral reinforcement assembly 3 is in two sets, and the reinforcement storage plate 42, the reinforcement delivery wheel group 43, and the tension monitoring assembly 44 are in two sets and are arranged in a one-to-one correspondence with the spiral reinforcement assembly 3; the two sets of spiral reinforcement assemblies 3 are symmetrically arranged along the axis of the nozzle 11, so that double spiral micro-reinforcements will be formed on the concrete strip 10.

[0034] This invention also provides a method for arranging spiral microribs during concrete 3D printing, based on the aforementioned device for arranging spiral microribs during concrete 3D printing; specifically including the following steps: Set the pitch P of the spiral groove wheel 31 and the extrusion speed v of the 3D printing device 1, calculate the angular velocity ω=v / P of the rotary drive device, and obtain the rotational speed n of the spiral groove wheel about its axis. Start the 3D printing device to extrude concrete, while controlling the spiral groove wheel to rotate around its axis at a speed n and the cylinder 2 to rotate around the axis of the nozzle; The feeding assembly 4 feeds the micro-ribs 35 into the spiral groove wheel 31. After passing through the rib outlet tube 32, the micro-ribs 35 enter the output cavity and are spirally embedded in the concrete strip 10 formed by extrusion. After printing, the concrete component is cured according to standard procedures, so that the spiral micro-reinforcement 35 and the concrete strip 10 form a synergistic bond of mechanical interlocking force and chemical bonding force.

[0035] Example 1: Taking a concrete strip 10 with a printing width of 30mm and a thickness of 20mm as an example, basalt fiber micro-reinforcements 35 with a diameter of 1mm are used. The specific implementation steps are as follows: The spiral reinforcement assembly 3 is installed in the installation cavity. The pitch of the spiral groove in the spiral groove wheel 31 is 20mm. The reinforcement tube 32 extends 10mm into the output cavity. The reinforcement storage plate 42 of the reinforcement feeding assembly 4 is equipped with basalt fiber micro-reinforcement 35. Parameter settings: Set the printing extrusion speed v=100mm / s, calculate the rotational angular velocity of the rotary drive ω=v / P=5rad / s, and obtain the rotational speed of the spiral groove wheel around its axis as 47.7r / min. The feed speed is linked to the rotational speed. Start the 3D printing device 1 to extrude C30 grade 3D printed concrete, while controlling the spiral groove wheel 31 to rotate around its axis at a speed of 47.7 r / min and the cylinder to rotate around the nozzle axis. The reinforcement feeding assembly 4 continuously feeds basalt fiber micro-reinforcements 35. The basalt fiber micro-reinforcements 35 are guided by the spiral groove wheel 31 and positioned by the reinforcement tube 32. They are spirally embedded into the concrete strip 10 to form a continuous spiral micro-reinforcement 35 with a pitch of 20mm. After printing, concrete strip 10 was placed in a standard curing room (temperature 20±2℃, humidity above 95%) for curing for 28 days; Tests were conducted, and the results showed that the flexural strength of concrete strip 10 increased by 45%, the interlaminar shear strength increased by 38%, the micro-reinforcement 35 did not experience pull-out failure in the pull-out test, and the interfacial bond strength reached over 2.5 MPa.

[0036] This invention utilizes the bonding effect between the spiral micro-ribs 35 and the 3D-printed concrete strips 10 to achieve a synergistic effect of mechanical interlocking force, chemical bonding force, and circumferential constraint: During the 3D printing extrusion process, the concrete strip 10 is in a plastic flow state, and the spiral micro-ribs 35 are synchronously wrapped and embedded inside it as the concrete is extruded. The spiral three-dimensional structure causes the micro-ribs 35 to interlock with the concrete strip 10. Compared to the existing technology of embedded linear micro-ribs 35, the effective bonding length of the spiral micro-ribs 35 is increased by 30% to 80% (calculated based on the spiral length), and the contact area is significantly improved. The spiral circumferential protrusions form a mechanical interlock with the concrete matrix. When the concrete is subjected to tension / shear, the spiral segment of the micro-ribs 35 can resist the pull-out force, preventing the interface slippage between the micro-ribs 35 and the concrete strip 10. Pull-out tests show that the pull-out resistance of the spiral micro-ribs 35 is 40% to 60% higher than that of the linear micro-ribs 35.

[0037] After the surface of the micro-reinforced 35 is roughened, etched, or coated with a cement-based adhesive, during the concrete hardening process, the cement hydration products (CSH gel, Ca(OH)2 crystals) form a chemical adsorption and crystallization bond with the surface of the micro-reinforced 35: the surface active groups of the basalt fiber reinforcement form chemical bonds with the cement hydration products, and the oxide layer of the stainless steel reinforcement forms a physical-chemical composite bond with the cement matrix; the spiral winding structure of the micro-reinforced 35 causes uniform compressive stress to be generated at the interface when the concrete shrinks during the hardening process, further strengthening the chemical bond and increasing the interfacial bond strength by 20%~35%.

[0038] The spiral-shaped micro-reinforcements 35 form a continuous circumferential constraint system in the concrete strip 10. When the concrete strip 10 is loaded and microcracks are generated: the circumferential tensile force of the spiral-shaped micro-reinforcements 35 can limit the opening and extension of cracks, controlling the crack width to less than 0.1 mm; the spiral-shaped micro-reinforcements 35 at the interlayer interface can bridge the upper and lower printed layers, improve the interlayer shear strength, solve the problem of weak interlayers in 3D printed concrete, and improve the interlayer shear strength by 30%~50%; when the component is subjected to bending, the toughening effect of the spiral-shaped micro-reinforcements 35 can transform the concrete from brittle failure to ductile failure, and improve the ultimate deflection by 50%~100%.

[0039] This invention is not limited to the specific embodiments described above. The invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.

Claims

1. A device for arranging spiral micro-ribs during concrete 3D printing, characterized in that, The device includes a cylinder disposed at the bottom of the nozzle and rotating around the nozzle axis with the nozzle; a spiral rib-laying assembly installed on the outside of the cylinder and guiding the microribs into the cylinder; and a rib-feeding assembly installed on the outside of the 3D printing device and used to deliver the microribs into the spiral rib-laying assembly; the cylinder is provided with an output cavity coaxially connected to the nozzle. The spiral reinforcement assembly includes a spiral groove wheel disposed on the outside of the cylinder and having spiral grooves on its surface, and a reinforcement tube with one end connected to the spiral groove and the other end connected to the output cavity; the spiral groove wheel rotates in conjunction with the reinforcement feeding assembly; the lead of the spiral groove is matched with the extrusion speed of the 3D printing device.

2. The device for arranging spiral micro-ribs in the concrete 3D printing process according to claim 1, characterized in that, The spiral reinforcement assembly also includes a transmission component disposed on the side of the spiral groove wheel away from the reinforcement outlet pipe and used for secondary transmission of the micro-reinforcements conveyed by the reinforcement feeding assembly.

3. The device for arranging spiral micro-ribs during concrete 3D printing according to claim 1, characterized in that, A rotary drive unit for controlling the rotation of the cylinder is provided on the outside of the 3D printing device; A rotary drive device is provided on the outside of the cylinder to control the rotation of the spiral groove wheel around its axis; the pitch of the spiral groove is P, the extrusion speed of the 3D printing device is v; the angular velocity of the rotary drive device is ω, P=v / ω.

4. The device for arranging spiral micro-ribs during concrete 3D printing according to claim 1, characterized in that, The spiral groove is an equidistant spiral groove with a pitch of P = 10~50mm. The diameter of the micro-rib is 0.5~1.5mm, and the width and depth of the spiral groove are adapted to the diameter of the micro-rib. The rotational speed of the cylinder is 0~30r / min.

5. The device for arranging spiral micro-ribs during concrete 3D printing according to claim 1, characterized in that, The micro-ribs are any one of basalt fiber ribs, stainless steel micro-ribs, and carbon fiber ribs.

6. The device for arranging spiral micro-ribs in the concrete 3D printing process according to claim 2, characterized in that, The rib feeding assembly includes a bracket set outside the barrel in the 3D printing device, a rib storage plate mounted on the bracket, a rib feeding wheel set mounted at the bottom of the bracket, and a tension monitoring assembly mounted on the bracket for monitoring the conveying tension of the microribs.

7. The device for arranging spiral micro-ribs during concrete 3D printing according to claim 6, characterized in that, The transmission assembly includes a transmission roller assembly disposed outside the spiral groove wheel for conveying microribs into the spiral groove, and a guide sleeve disposed away from the spiral groove wheel for guiding the microribs.

8. The device for arranging spiral micro-ribs during concrete 3D printing according to claim 7, characterized in that, It also includes a shell that is fitted onto the outside of the cylinder and forms an installation cavity between the shell and the cylinder, wherein the spiral reinforcement assembly is located inside the installation cavity and the guide sleeve is disposed on the outside of the shell.

9. The device for arranging spiral micro-ribs in the concrete 3D printing process according to claim 7, characterized in that, The spiral grooved wheel is mounted on the transfer roller assembly via a mounting bracket and is rotatably engaged with the mounting bracket; the transfer roller assembly includes a mounting plate and rollers mounted on the mounting plate for conveying micro-ribs; the mounting plate and the outer casing are slidably engaged along the axial direction of the nozzle; The spiral reinforcement assembly consists of two sets, and the reinforcement storage plate, reinforcement feeding wheel set, and tension monitoring assembly also consist of two sets, each corresponding to one of the spiral reinforcement assembly; the two sets of spiral reinforcement assemblies are symmetrically arranged along the axis of the nozzle.

10. A method for arranging spiral micro-ribs during concrete 3D printing, characterized in that, The apparatus for arranging spiral microribs during concrete 3D printing according to any one of claims 1-9 specifically includes the following steps: Set the pitch P of the spiral grooved wheel and the extrusion speed v of the 3D printing device, calculate the angular velocity ω=v / P of the rotary drive device, and obtain the rotational speed n of the spiral grooved wheel about its axis. Start the 3D printing device to extrude concrete, while controlling the spiral groove wheel to rotate around its axis at a speed n and the cylinder to rotate around the axis of the nozzle; The feed assembly feeds the micro-reinforcement into the spiral groove wheel. The micro-reinforcement enters the output chamber through the spiral reinforcement assembly and is spirally embedded in the concrete strip formed by extrusion. After printing, the concrete component is cured according to standard procedures, so that the spiral micro-reinforcements form a synergistic bond with the concrete matrix through mechanical interlocking and chemical adhesion.

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