Honeycomb steel pipe constraint block stone concrete bulletproof structure and preparation method thereof

Abstract

The invention provides a honeycomb steel pipe restrained block stone concrete bullet shielding structure and a preparation method thereof. The structure comprises a honeycomb steel pipe structure and block stone concrete filled in the honeycomb steel pipe structure; the honeycomb steel pipe structure comprises a plurality of pipe body structure units, an outer frame steel plate and an internal additional steel plate; each pipe body structure unit is formed by integrally forming a steel plate, the two ends of each steel plate are both bent inwards to form folded edges with the inner angle being 120 degrees, the length of the two folded edges is consistent with the length of a steel plate body section between the two folded edges, and the pipe body structure units and other pipe body structure units of the same specification are spliced and enclosed to form a regular hexagon. The multiple pipe body structure units are spliced and enclosed to form multiple regular hexagon cells, and the regular hexagon cells, the outer frame steel plates and the internal additional steel plates are welded into a whole to jointly form the honeycomb steel pipe structure. The block stone concrete comprises block stone aggregate and a cement-based material. The structure is excellent in anti-penetration performance and high in multi-shot / repeated strike resistance.

Description

Technical Field

[0001] This invention relates to the field of building protective structure technology, and in particular, to a honeycomb steel pipe confined concrete shielding structure and its preparation method. Background Technology

[0002] Traditional plain concrete or reinforced concrete protective structures are prone to typical damage such as collapse, pitting, brittle fracture, and penetration under high-speed penetration impact, resulting in a severe reduction in overall protective performance and unsatisfactory protective effectiveness. Steel-confined concrete mainly relies on the three-dimensional confinement of the core concrete by the steel pipe to improve its strength, ductility, and toughness, thereby enhancing its overall penetration resistance, but the improvement effect is limited. In addition, existing protective structures have weak resistance to multiple / repeated impacts, and damage from multiple impacts tends to accumulate and spread, seriously affecting the overall protective effectiveness of the structure.

[0003] Therefore, there is an urgent need for a new structure that combines resistance to penetration, resistance to multiple attacks, the ability to induce projectile yaw, and suitability for the protection of large-caliber weapons. Summary of the Invention

[0004] To address the technical problems existing in the prior art, this invention provides a honeycomb steel tube-constrained concrete block projectile shielding structure and its preparation method. This structure is a protective structure with excellent penetration resistance, strong resistance to multiple / repeated hits, and functions in abrading the projectile and inducing yaw. It also has comprehensive advantages such as simple construction and good economy. The honeycomb steel tube-constrained concrete block projectile shielding structure provided by this invention has a protection mechanism of multiple constraint effects + block abrasion energy dissipation + yaw mechanism, specifically reflected in the constraint effect of the steel tube on the concrete, the synergistic effect between the structural units, and the abrasion and yaw-inducing effect of the blocks on the projectile.

[0005] To achieve the above objectives, the present invention provides a honeycomb steel tube constrained boulders concrete shielding structure, comprising a honeycomb steel tube structure and boulders concrete filled inside the honeycomb steel tube structure. The honeycomb steel pipe structure includes multiple pipe structure units, an outer frame steel plate, and an internal additional steel plate; The tube structure unit is integrally formed from a steel plate. Both ends of the steel plate are bent inward to form folded edges with an inner angle of 120°. The length of the two folded edges is the same as the length of the steel plate body section between the two folded edges. The tube structure unit is spliced ​​with other tube structure units of the same specification to form a regular hexagon. Multiple tube structure units are spliced ​​together to form multiple regular hexagonal cells. The regular hexagonal cells are welded together with the outer frame steel plate and the internal additional steel plate to form a honeycomb steel tube structure. The rubble concrete includes rubble aggregate and cement-based materials.

[0006] Furthermore, the stone aggregate is granite, basalt, quartzite or corundum stone, with a uniaxial compressive strength of not less than 100 MPa.

[0007] Furthermore, the stone aggregate is pre-stacked randomly in regular hexagonal cells.

[0008] Furthermore, the minimum size of the stone aggregate is not less than 1.5 times the diameter of the penetrating projectile.

[0009] Furthermore, the ratio of the side length of the regular hexagonal cell to the diameter of the penetrating projectile is 15 to 25.

[0010] Furthermore, the outer frame steel plate is composed of two L-shaped steel plates welded together. The side length of the L-shaped steel plate is adapted to the outer contour side length of the honeycomb steel pipe structure, and the thickness of the L-shaped steel plate is consistent with the thickness of the steel plate.

[0011] Furthermore, the honeycomb steel pipe structure is made of carbon structural steel, alloy structural steel, or stainless steel.

[0012] This invention also provides a method for preparing the above-mentioned honeycomb steel tube confined boulders concrete elastic shielding structure, comprising the following steps: Step 1: Select steel plates that meet the design strength requirements and cut them into sheet materials according to the design dimensions; Step 2: Bend both ends of the sheet metal into tubular structural units with an inner angle of 120°; Step 3: Select steel with a length and width that match the overall outline of the internal honeycomb structure and process it into an L-shaped steel plate; Step 4: Assemble multiple standardized tubular structural units with two L-shaped steel plates and internal additional steel plates by welding to form an overall honeycomb structure; Step 5: After assembling and welding the overall honeycomb frame, pile up stone aggregate inside the steel pipe cavity; then inject cement-based material into the steel pipe cavity under high pressure. Step Six: Perform post-construction maintenance.

[0013] Furthermore, in step two, a CNC bending machine is used to bend both ends of the steel plate into standardized tubular structural units with an inner angle of 120°.

[0014] Furthermore, in step five, cement-based material is injected into the cavity of the steel pipe under high pressure. Specifically, a temporary closed pressure-bearing system is first established at both ends of the steel pipe. Then, a flange with a valve is installed at each end of the steel pipe, and a grouting hole is opened at the lower flange. In the initial stage of pouring, the exhaust valve is opened to expel the air in the pipe. After the air is completely expelled, grouting begins from the grouting port at the bottom of the steel pipe. When the cement-based material flows out stably from the exhaust port and has the same properties as the pumped cement-based material, the exhaust valve is closed, grouting is stopped, and the temporary flange device is removed.

[0015] The present invention has the following beneficial effects: (1) The present invention provides a honeycomb steel pipe constrained block concrete elastic shielding structure, including a honeycomb steel pipe structure and block concrete filled inside the honeycomb steel pipe structure; the honeycomb steel pipe structure includes multiple pipe structure units, an outer frame steel plate and an inner additional steel plate; the pipe structure unit is integrally formed by steel plates, both ends of the steel plate are bent inward to form folded edges with an inner angle of 120°, the length of the two folded edges is consistent with the length of the steel plate body section between the two folded edges, the pipe structure unit is spliced ​​with other pipe structure units of the same specification to form a regular hexagon; multiple pipe structure units are spliced ​​with each other to form multiple regular hexagonal cells, the regular hexagonal cells are welded with the outer frame steel plate and the inner additional steel plate to form a honeycomb steel pipe structure; the block concrete includes block aggregate and cement-based materials.

[0016] (2) The honeycomb steel pipe confined concrete bulletproof structure provided by this invention has outstanding anti-penetration performance due to the synergistic effect of multiple confinement effects. During bullet penetration, the outer hexagonal steel pipe cells and the core concrete form a synergistic protection system. In addition, during bullet penetration, the bullet is not only constrained by the concrete, but also by the hexagonal steel pipe cells, while adjacent steel pipe concrete units also exert additional constraints, forming a regional synergistic anti-penetration mechanism, which significantly enhances the protective effectiveness of the structure. This bulletproof structure can be assembled in a standardized manner, which facilitates the processing and installation of components, as well as the replacement and repair of the structure after damage. Furthermore, different protection requirements can be met by adjusting the unit size, steel plate thickness, and block gradation.

[0017] (3) The high-strength boulders pre-stacked inside the regular hexagonal cell steel pipe in this invention have a dual anti-penetration function: on the one hand, the strength difference between the boulders and the filling cement matrix causes the projectile to generate an asymmetric force during penetration, inducing the projectile to yaw; on the other hand, the high hardness of the boulders is used to achieve the effects of energy dissipation, abrasion, or upsetting of the projectile. In view of the technical problem that relying solely on the passive constraint of the concrete by the regular hexagonal cell steel pipe to improve the overall anti-penetration performance of the structure is limited, this invention pre-stacks high-strength boulders inside the regular hexagonal cell steel pipe as a reinforcing medium (i.e., the boulder aggregate is granite, basalt, quartzite, or corundum boulders with a uniaxial compressive strength of not less than 100 MPa). Utilizing their high hardness and high strength characteristics, the boulders-concrete system induces the projectile to yaw or abrade the projectile during penetration, achieving a dual anti-penetration mechanism and significantly improving the anti-penetration performance of the structure.

[0018] (4) This invention takes into account the proportional relationship between the characteristic dimensions of the hexagonal cell steel pipe and the diameter of the penetrating projectile, that is, the ratio of the side length of the hexagonal cell to the diameter of the penetrating projectile is 15~25, which maximizes the constraint effect of the steel pipe on the concrete and can resist large-caliber bullets or bunker busters. In addition, this invention relies on the high strength, large size and irregularity of the boulders to achieve energy dissipation and abrasion of the projectile during the penetration process, so that the projectile is subjected to asymmetrical forces and induces the projectile to yaw. The yaw is mainly achieved by the boulders material. And when the minimum size of the boulders aggregate is not less than 1.5 times the diameter of the penetrating projectile, it has the best protective effect.

[0019] (5) The boulders of the present invention are randomly stacked, and the boulders do not need to be processed into regular cubic modules, which simplifies the construction process; the irregular distribution of the boulder-concrete interface also effectively disrupts the continuity of the penetration process, avoiding the problem of large differences in strength between the interface and the boulders. In addition, the present invention introduces a mechanism for induced projectile yaw and overall structural anti-penetration, which significantly improves the anti-penetration performance of the structure.

[0020] (6) The high-pressure grouting process used in this invention can significantly improve the density of the structure. This process mainly involves drawing a vacuum inside the steel pipe and then using high-pressure grouting to fully fill the gaps between the boulders with cement-based materials, forming a dense steel pipe-constrained boulder concrete structure. This effectively avoids defects such as voids and debonding that are prone to occur in traditional casting processes, not only improving construction efficiency but also ensuring a tight bond between material interfaces and improving the overall quality of the structure. In addition, this invention uses a pre-irregularly stacked boulders + high-pressure grouting process, which is simple; and the steel pipe can be used as a template for stacking boulders and during the casting process. The boulders are readily available and do not require further processing, and the steel plates can be pre-processed in the factory, making construction convenient.

[0021] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0022] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is an overall structural diagram of the honeycomb steel pipe constrained block concrete elastic shielding structure of the present invention; Figure 2 This is a schematic diagram of the honeycomb steel pipe structure of the honeycomb steel pipe constrained block concrete elastic structure of the present invention; Figure 3 This is a schematic diagram of the tube structure unit of the honeycomb steel tube constrained block concrete elastic structure of the present invention; Figure 4 This is a schematic diagram of the internal honeycomb steel pipe structure (without the outer frame steel plate) in the honeycomb steel pipe constrained block concrete elastic structure of the present invention. Figure 5 This is a schematic diagram of the outer frame steel plate in the honeycomb steel pipe constrained block concrete elastic structure of the present invention; Figure 6 This is a cross-sectional view of the steel pipe-confined concrete in the honeycomb steel pipe-confined block concrete elastic structure of the present invention; Figure 7 This is a construction flowchart of the honeycomb steel pipe constrained block concrete elastic shield structure of the present invention; Figure 8 This is a schematic diagram of the projectile entering the projectile shielding structure in the honeycomb steel pipe constrained boulders concrete projectile shielding structure of the present invention. The components include: 1. outer frame steel plate, 2. pipe structure unit, 3. internal additional steel plate, 4. rubble concrete, 5. rubble aggregate, and 6. cement-based materials. Detailed Implementation

[0023] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0024] See Figures 1 to 6 The present invention provides a steel pipe-constrained boulders concrete bulletproof structure resistant to penetration, comprising a honeycomb steel pipe structure and boulders concrete 4 filled inside the honeycomb steel pipe structure; The honeycomb steel pipe structure includes multiple pipe structure units 2, an outer frame steel plate 1, and an internal additional steel plate 3; The tube structure unit 2 is integrally formed from a steel plate. Both ends of the steel plate are bent inward to form folded edges with an inner angle of 120°. The length of the two folded edges is consistent with the length of the steel plate body section between the two folded edges. The tube structure unit 2 is spliced ​​with other tube structure units 2 of the same specification to form a regular hexagon. Multiple tube structure units 2 are spliced ​​together to form multiple regular hexagonal cells. The regular hexagonal cells are welded together with the outer frame steel plate 1 and the inner additional steel plate 3 to form a honeycomb steel pipe structure. The rubble concrete 4 includes rubble aggregate 5 and cement-based material 6. Preferably, the cement-based material 6 is an ultra-high strength cement-based material.

[0025] The tube body is formed by cold bending. According to design requirements, a CNC bending machine is used to bend both ends of the steel plate into tube structural units with an inner angle of 120°. Each tube structural unit, the outer frame steel plate 1, and the internal additional steel plate 3 are assembled into a honeycomb steel tube structure by welding. The outer frame steel plate is composed of two L-shaped steel plates welded together. The side length of the L-shaped steel plate matches the outer contour side length of the honeycomb steel tube structure, and the thickness of the L-shaped steel plate is consistent with the thickness of the steel plate.

[0026] The honeycomb steel pipe structure can be made of carbon structural steel, alloy structural steel, or stainless steel. High-strength, large-sized boulders are placed inside the pipe cavity; these boulders are preferably made of high-hardness materials such as granite, basalt, quartzite, or corundum. Then, a cement-based material is poured using a high-pressure grouting process to form a dense steel pipe-confined boulder concrete structure. The upper and lower surfaces of the honeycomb steel pipe-confined boulder concrete bullet shield structure provided by this invention are arranged perpendicular to the direction of projectile penetration. When a bullet impacts the bullet shield structure at high speed, the projectile will first contact the concrete part of the bullet shield structure (e.g.,...). Figure 8 (As shown).

[0027] This invention provides a honeycomb steel tube-confined concrete bulletproof structure, whose outstanding anti-penetration performance lies in the synergistic effect of multiple confinement effects. During bullet penetration, the outer hexagonal steel tube cells and the core concrete form a collaborative protection system. Furthermore, during bullet penetration, the bullet is not only constrained by the concrete but also by the hexagonal steel tube cells, while adjacent steel tube concrete units also exert additional constraints, forming a regional collaborative anti-penetration mechanism that significantly enhances the structure's protective effectiveness.

[0028] To address the technical problem that relying solely on the passive constraint of concrete by the steel tube cells has limited effect on improving the overall penetration resistance of a structure, this invention uses high-strength boulders (i.e., the boulders are granite, basalt, quartzite, or corundum boulders with a uniaxial compressive strength of not less than 100 MPa) stacked inside the hexagonal steel tube cells as a reinforcing medium. Utilizing their high hardness and high strength characteristics, the boulders-concrete system abrades the projectile during penetration and induces the projectile to yaw, achieving a dual penetration resistance mechanism and significantly improving the structure's penetration resistance.

[0029] The ratio of the side length of the hexagonal cell to the diameter of the penetrating projectile is 15-25. This maximizes the constraint effect of the steel pipe on the concrete and can withstand large-caliber bullets or bunker buster bombs. Furthermore, this invention utilizes the high strength, large size, and irregular shape of the aggregate blocks to dissipate energy and abrade the projectile during penetration, subjecting it to asymmetrical forces and inducing yaw. This yaw is primarily achieved through the aggregate blocks. Optimal protective effect is achieved when the minimum size of the aggregate blocks is not less than 1.5 times the diameter of the penetrating projectile.

[0030] The present invention employs irregularly stacked boulders, eliminating the need for processing them into regular cubic modules, thus simplifying the construction process. The irregular distribution of the boulders-concrete interface also effectively disrupts the continuity of the penetration process, avoiding the problem of significant strength differences between the interface and the boulders. Furthermore, the present invention introduces a mechanism for induced projectile yaw and overall structural synergy in resisting penetration, significantly improving the structure's anti-penetration performance.

[0031] like Figure 7 As shown, the manufacturing process of the honeycomb steel pipe confined concrete elastic shielding structure of the present invention is as follows: Step 1: Select steel plates that meet the design strength requirements and cut them into plates according to the design dimensions. The length, width, and thickness tolerances of the steel plates should be controlled within ±0.5 mm. After cutting, the cut edges of the plates are machined to eliminate cutting defects such as heat-affected zones, hardened layers, or microcracks. Step 2: Use a CNC bending machine to bend both ends of the steel plate into standardized tubular structural units with an inner angle of 120°. Based on the steel plate thickness and the 120° bending angle requirement, design or select suitable upper and lower dies. The opening width of the lower die is set to 8 times the plate thickness. After installing the dies, bend the plate. A 0.5°~1° overbending allowance must be pre-set to compensate for springback, ensuring that the angle deviation after forming is no greater than ±0.5° and the bending radius error does not exceed 0.1 times the plate thickness. Step 3: Perform dimensional and quality inspections on the standardized tube structure units formed by cold bending, including the inspection of misalignment, edge angle, and right angle; among them, the misalignment of the weld should not exceed 1.5 mm, and the edge angle should meet the requirement of not exceeding 5 mm. Step 4: Select steel with a length and width that match the overall outline of the internal honeycomb structure and process it into an L-shaped steel plate using a CNC bending machine; the bending requires a pre-set overbending amount of 0.5°~1° to compensate for springback, ensuring that the angle deviation after forming is no greater than ±0.5° and the bending radius error is no more than 0.1 times the plate thickness; Step 5: Assemble multiple standardized tubular structural units with two L-shaped steel plates and internal additional steel plates by welding to form a regular hexagonal honeycomb steel pipe structure. All welds are full penetration butt welds, located at the connection between the frame and the grid structure and at the frame joints. The distance between adjacent welds should be greater than 300 mm. Step 6: After assembling and welding the honeycomb steel pipe structure, place high-strength, large-sized stones inside the steel pipe cavity. The stones should preferably be made of high-hardness stone such as granite, basalt, quartzite, or corundum, with a uniaxial compressive strength of not less than 100 MPa, and the minimum size of the stones should not be less than 1.5 times the diameter of the penetrating projectile. Step 7: Establish a temporary closed pressure system at both ends of the steel pipe. Install a flange with a valve at each end of the steel pipe, with a separate grouting hole required for the lower flange. In the initial stage of pouring, open the vent valve to expel air from the pipe. After the air has been expelled, start grouting from the grouting port at the bottom of the steel pipe. When the cement-based material flows steadily from the vent port and its properties are consistent with the pumped cement-based material, close the vent valve, stop grouting, and remove the temporary flange device. Step 8: Perform proper maintenance afterwards.

[0032] The high-pressure grouting process employed in this invention significantly improves the density of the structure. This process primarily involves creating a vacuum inside a steel pipe, followed by high-pressure grouting to fully fill the gaps between the boulders with mortar, forming a dense steel-pipe-constrained boulder concrete structure. This effectively avoids defects such as voids and debonding that are common in traditional casting processes, not only improving construction efficiency but also ensuring a tight bond between material interfaces and enhancing the overall structural quality. Furthermore, this invention employs a pre-arranged irregular stacking of boulders combined with high-pressure grouting, resulting in a simple process. The steel pipe serves as a template for stacking boulders and during the casting process; the boulders are readily available and require no further processing; and the steel plates can be pre-processed in the factory, simplifying construction.

[0033] The anti-penetration mechanism of this invention is based on the synergistic effect of multiple constraint effects. During the projectile penetration process, the constraint effect of concrete on the projectile, the constraint effect of steel pipe on its core concrete, and the additional constraints provided by adjacent units form a regional synergistic anti-penetration mechanism, which significantly increases the penetration resistance of the projectile, reduces the penetration depth of the projectile, effectively limits damage propagation, and improves the anti-penetration performance of the structure. The high-strength boulders stacked within the steel pipe cavity possess dual anti-penetration capabilities: firstly, the discontinuous distribution of the boulders at the cement-based material interface and the strength difference between the boulders and the filling mortar matrix induce asymmetric forces in the projectile, causing it to "yaw"; secondly, within the steel pipe-constrained boulder concrete structure, it is not only constrained by the concrete but also by the constraint effect exerted by the outer steel pipe and the additional constraint exerted by the surrounding steel pipe concrete units, placing it under triaxial compression. This significantly improves the strength, ductility, and toughness of the boulder concrete, thereby enhancing its overall anti-penetration performance. High-hardness boulders such as granite, basalt, quartzite, or corundum are recommended, with a uniaxial compressive strength of not less than 100 MPa. The minimum size of the boulders should not be less than 1.5 times the diameter of the penetrating projectile, and the gradation between the boulders should be considered. The ratio of the characteristic dimension of the honeycomb steel pipe (i.e., the side length of the regular hexagonal cell) to the diameter of the penetrating projectile should ideally be between 15 and 25. The external steel pipe material can be selected from carbon structural steel or alloy structural steel, or stainless steel, depending on the project requirements, to meet the protection needs of special areas. The bullet shielding structure of this invention has high adaptability. According to the requirements of the diameter of the protected weapon bullet, different protection needs can be matched by adjusting the pipe wall thickness, cross-sectional dimensions, and the gradation and size of the stones.

[0034] The above description is merely a preferred embodiment of the present invention and is not intended to limit the 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 honeycomb steel pipe-confined concrete block shield structure, characterized in that, It includes a honeycomb steel pipe structure and rubble concrete filling the inside of the honeycomb steel pipe structure; The honeycomb steel pipe structure includes multiple pipe structure units, an outer frame steel plate, and an internal additional steel plate; The tube structure unit is integrally formed from a steel plate. Both ends of the steel plate are bent inward to form folded edges with an inner angle of 120°. The length of the two folded edges is the same as the length of the steel plate body section between the two folded edges. The tube structure unit is spliced ​​with other tube structure units of the same specification to form a regular hexagon. Multiple tube structure units are spliced ​​together to form multiple regular hexagonal cells. The regular hexagonal cells are welded together with the outer frame steel plate and the internal additional steel plate to form a honeycomb steel tube structure. The rubble concrete includes rubble aggregate and cement-based materials.

2. A honeycomb steel pipe-confined boulders concrete elastic shielding structure according to claim 1, characterized in that, The stone aggregate is made of granite, basalt, quartzite or corundum blocks, with a uniaxial compressive strength of not less than 100 MPa.

3. The honeycomb steel pipe-confined boulders concrete elastic shielding structure according to claim 1, characterized in that, The stone aggregate is pre-stacked randomly in regular hexagonal cells.

4. The honeycomb steel pipe-confined boulders concrete elastic shielding structure according to claim 1, characterized in that, The minimum size of the stone aggregate is not less than 1.5 times the diameter of the penetrating projectile.

5. The honeycomb steel pipe-confined boulders concrete elastic shielding structure according to claim 1, characterized in that, The ratio of the side length of the regular hexagonal cell to the diameter of the penetrating projectile is 15 to 25.

6. The honeycomb steel pipe-confined boulders concrete elastic shielding structure according to claim 1, characterized in that, The outer frame steel plate is composed of two L-shaped steel plates welded together. The side length of the L-shaped steel plate is adapted to the outer contour side length of the honeycomb steel pipe structure, and the thickness of the L-shaped steel plate is consistent with the thickness of the steel plate.

7. A honeycomb steel pipe-confined boulders concrete elastic shielding structure according to claim 1, characterized in that, The honeycomb steel pipe structure is made of carbon structural steel, alloy structural steel, or stainless steel.

8. A method for preparing a honeycomb steel tube-confined boulders concrete elastic shielding structure according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Select steel plates that meet the design strength requirements and cut them into sheet materials according to the design dimensions; Step 2: Bend both ends of the sheet metal into tubular structural units with an inner angle of 120°; Step 3: Select steel with a length and width that match the overall outline of the internal honeycomb structure and process it into an L-shaped steel plate; Step 4: Assemble multiple standardized tubular structural units with two L-shaped steel plates and internal additional steel plates by welding to form an overall honeycomb structure; Step 5: After assembling and welding the overall honeycomb frame, pile up stone aggregate inside the steel pipe cavity; then inject cement-based material into the steel pipe cavity under high pressure. Step Six: Perform post-construction maintenance.

9. The preparation method according to claim 8, characterized in that, In step two, a CNC bending machine is used to bend both ends of the steel plate into standardized tubular structural units with an inner angle of 120°.

10. The preparation method according to claim 8, characterized in that, In step five, cement-based material is injected into the cavity of the steel pipe under high pressure. Specifically, a temporary closed pressure system is first established at both ends of the steel pipe. Then, a flange with a valve is installed at each end of the steel pipe, and a grouting hole is opened at the lower flange. In the initial stage of pouring, the exhaust valve is opened to expel the air in the pipe. After the air is completely expelled, grouting begins from the grouting port at the bottom of the steel pipe. When the cement-based material flows out steadily from the exhaust port and has the same properties as the pumped cement-based material, the exhaust valve is closed, grouting is stopped, and the temporary flange device is removed.

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