Honeycomb confined high-ductility compressive yield concrete member and preparation method thereof

Abstract

The invention discloses a honeycomb confined high-ductility compressive yield concrete member and a preparation method thereof.The honeycomb confined high-ductility compressive yield concrete member comprises a honeycomb framework with the negative Poisson's ratio effect, the Poisson's ratio of the honeycomb framework is-0.3--0.08, the honeycomb framework comprises multiple layers of unit cell structures arranged in the same direction, each layer of unit cell structure comprises multiple honeycomb unit cells in the shape of a concave hexagonal prism, and the honeycomb unit cells are arranged in the same direction; each honeycomb unit cell comprises two adjacent plates which are oppositely arranged, the two opposite sides of each adjacent plate extend towards the middle of the corresponding adjacent plate to form inclined butt joint plates, the inclined butt joint plates on the same sides of the two adjacent plates are connected, and the adjacent plates of every two adjacent honeycomb unit cells in each layer of unit cell structure are connected together. An interlayer plate is connected between the joints of the two inclined butt joint plates in every two adjacent layers of unit cell structures; and the cement matrix is coated on the honeycomb structure. The invention solves the problems that the existing ECC still has insufficient rolling property, the stress-strain curve of the ECC still can be softened after reaching peak stress, and a long yield platform similar to metal or the long yield platform when the ECC is stretched cannot be formed.

Description

Technical Field

[0001] This invention relates to the field of concrete component technology, specifically to a honeycomb-confined high-ductility compressive yield concrete component and its preparation method. Background Technology

[0002] Ordinary cement-based materials exhibit significant brittleness under compression, with their stress-strain curves dropping sharply after reaching peak strength, leading to sudden fracture of the mass. In contrast, fiber-reinforced ECC (high-ductility cement-based composite) shows improved compressive properties. The bridging effect of the fibers inhibits rapid crack propagation, resulting in a slower failure process and a smoother stress drop curve. However, this improvement is limited, and the compressive ductility of ECC remains insufficient. The fibers in ECC primarily provide residual strength after the peak stress, rather than true plastic deformation capacity. ECC masses still soften after reaching peak stress, failing to form a prolonged yield plateau similar to that of metals or themselves under tension; their compressive toughness is far lower than their tensile toughness. Therefore, the compressive behavior of ECC is essentially still dominated by rapid softening after the peak stress, and its compressive ductility has not been fundamentally improved. The core problem lies in the fact that its compression process is still dominated by post-peak softening, and it lacks a designable and controllable plateau stage. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, a honeycomb-confined high-ductility compressive yield concrete member and its preparation method are provided to solve the problem that the compressive ductility of existing ECC is still insufficient, and its stress-strain curve will still soften after reaching the peak stress, and it cannot form a long yield plateau like metal or itself under tension.

[0004] To achieve the above objectives, a honeycomb-confined high-ductility compressive-yielding concrete member is provided, comprising: A honeycomb framework with a negative Poisson's ratio effect, wherein the Poisson's ratio of the honeycomb framework is -0.3 to -0.08, the honeycomb framework includes multiple unit cell structures arranged in the same direction, each unit cell structure includes multiple honeycomb unit cells in the shape of concave hexagonal prisms, each honeycomb unit cell includes two adjacent plates arranged opposite each other, and oblique butt plates are formed by extending inward from the opposite sides of the adjacent plates to the middle of the adjacent plates. The oblique butt plates on the same side of the two adjacent plates are connected, and the adjacent plates of two adjacent honeycomb unit cells in each unit cell structure are connected together. An interlayer plate is connected between the connection points of the two oblique butt plates in two adjacent unit cell structures. A cement matrix is ​​used to encapsulate the honeycomb structure.

[0005] Furthermore, the honeycomb skeleton is made of ABS or PA6 material.

[0006] Furthermore, the reentry angle between the adjacent plate and the oblique butt plate is 60°~75°.

[0007] Furthermore, the relative density of the honeycomb unit cells is 0.15~0.35.

[0008] Furthermore, the width of the adjacent plate is 15~30mm, and the width of the oblique butt plate is 8~15mm.

[0009] Furthermore, the cement matrix is ​​ECC, UHPC, FRC, or SCC.

[0010] Furthermore, the honeycomb skeleton is formed by 3D printing.

[0011] This invention provides a construction method for honeycomb-confined high-ductility compressive yield concrete members, comprising the following steps: Prepare a honeycomb framework with a negative Poisson's ratio effect; The honeycomb skeleton is placed inside the mold; A cement matrix is ​​poured into the mold, and the cement matrix covers the honeycomb structure to solidify and form a honeycomb-confined high-ductility compressive-yield concrete member.

[0012] The beneficial effects of this invention are that the honeycomb skeleton of the honeycomb-confined high-ductility compressive-yielding concrete member actively shrinks laterally when the member is under compression, thus constraining the cement matrix in the early stages of stress. This active constraint effect is significant, resulting in a substantial improvement in member ductility and a significant delay in the post-peak softening process. Compared to traditional concrete members, the honeycomb-confined high-ductility compressive-yielding concrete member of this invention exhibits a significantly slower rate of post-peak stress decline, maintains high load-bearing capacity in the post-peak stage, and significantly improves ductility, solving the problem of severe post-peak softening in existing constraint methods. Attached Figure Description

[0013] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the structure of a honeycomb-confined high-ductility compressive yield concrete member according to an embodiment of the present invention.

[0014] Figure 2 This is a perspective view of a honeycomb-confined high-ductility compressive yield concrete member according to an embodiment of the present invention.

[0015] Figure 3 This is a schematic diagram of the structure of a honeycomb unit cell according to an embodiment of the present invention.

[0016] Figure 4 This is a schematic diagram of the compression deformation mechanism of a honeycomb unit cell according to an embodiment of the present invention.

[0017] Figure 5 This is a schematic diagram of the compression deformation mechanism of the honeycomb skeleton in an embodiment of the present invention.

[0018] Figure 6 This is a schematic diagram of the compression deformation of a honeycomb-confined high-ductility compressive yield concrete member according to an embodiment of the present invention.

[0019] Figure 7 This is a uniaxial compressive stress-strain curve of the specimen.

[0020] Figure label: 1. Cellular skeleton, 11. Cellular unit cell, 111. Adjacent plate, 1111. 1112. Interlayer plate, 12. Adjacent plate width a. 11. 12. 13. 14. 15. 16. 17. 18. 19. 10. 10. 11. 12. 13. 14. 15. 16. 17. 1 Cement matrix 2. Detailed Implementation

[0021] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] Reference Figures 1 to 6 As shown, the present invention provides a honeycomb-confined high-ductility compressive yield concrete member, comprising a honeycomb skeleton 1 and a cement matrix 2.

[0024] The honeycomb skeleton 1 exhibits a negative Poisson's ratio effect. The Poisson's ratio of the honeycomb skeleton 1 is -0.3 to -0.08. The cement matrix 2 is encapsulated within the honeycomb structure.

[0025] The cement matrix 2 is ECC, UHPC, FRC or SCC.

[0026] In addition to engineering cement-based composites (ECC), cement-based materials with different properties, such as ultra-high performance concrete (UHPC), ordinary fiber-reinforced concrete (FRC), or self-compacting concrete (SCC), can also be used as the matrix of the composite structure. These materials each have advantages in terms of cost, compressive strength, and fluidity. When combined with a negative Poisson's ratio honeycomb structure, the active constraint mechanism of the honeycomb can effectively suppress the lateral expansion and cracking of the matrix material, thereby improving the overall deformation capacity of the component. By matching the strength, elastic modulus, and fiber content of the matrix, the peak load-bearing capacity, stiffness, and failure mode of the component can be flexibly adjusted to achieve the same effect as this invention in improving comprehensive mechanical properties through active constraint.

[0027] Specifically, the honeycomb skeleton 1 includes a multi-layered single-cell structure 11 and interlayer plates 12.

[0028] The multi-layer unit cell structures 11 are arranged in the same direction. Interlayer plates 12 connect adjacent unit cell structures. Multiple interlayer plates 12 connect adjacent unit cell structures.

[0029] Each cell structure 11 comprises multiple honeycomb cells 111. The multiple honeycomb cells 111 are arranged consecutively. Each honeycomb cell 111 is in the shape of a concave hexagonal prism.

[0030] In this embodiment, the cellular unit cell 111 includes an adjacent plate 1111 and an oblique abutment plate 1112.

[0031] Each cellular unit cell is equipped with two adjacent plates. The two adjacent plates are arranged opposite each other, i.e., the two adjacent plates 1111 are arranged parallel to each other with their surfaces facing each other. Each adjacent plate has two opposing layers in its width direction, and oblique butt plates 1112 extend inward from the opposite sides of the adjacent plates 1111 towards the center of the adjacent plates 1111. The oblique butt plates 1112 on the same side of the two adjacent plates 1111 are connected. The adjacent plates 1111 of two adjacent cellular unit cells 111 in each layer of unit cell structure 11 are connected together. An interlayer plate 12 connects the joints of the two oblique butt plates 1112 in two adjacent layers of unit cell structure 11.

[0032] In a preferred embodiment, the honeycomb skeleton 1 is made of acrylonitrile-butadiene-styrene copolymer (ABS) or polyamide 6 (PA6).

[0033] In addition to polymer composites such as PA6 or ABS, the honeycomb skeleton 1 can also be fabricated using metals (such as stainless steel and aluminum alloys), ceramic matrix composites, or advanced functional materials (such as shape memory alloys). These alternative materials may have unique advantages in terms of strength, toughness, high-temperature resistance, or special functions (such as self-healing). Honeycombs formed from these materials can all generate lateral active contraction under pressure based on their geometric topology, applying constraint forces to the core matrix. By selecting materials with different properties, the overall strength, energy absorption efficiency, and durability of the constraint structure can be significantly controlled, thereby achieving active constraint and ductility enhancement similar to those of this invention in different application scenarios.

[0034] As a preferred embodiment, the honeycomb skeleton 1 is 3D printed. The honeycomb skeleton in this invention is manufactured using 3D printing technology, enabling rapid molding without adding complex processes, and direct embedding into the mold for integral casting. Through integrated molding, the honeycomb skeleton and the cement matrix are bonded together as a whole during the initial hydration stage, achieving synchronous formation and coordinated deformation of the interface area. This helps to achieve a more uniform stress distribution during stress, improving the overall stability and reliability of the structure.

[0035] In some embodiments, the cellular unit cell can take the form of a rotating unit, a cross-chiral structure, etc. These structures can also generate a transverse active contraction effect under compression, effectively constraining the ECC matrix and thus improving post-peak deformation performance. By adjusting the geometric connection angle, wall thickness, and unit arrangement, the constraint stiffness and energy absorption capacity can be flexibly controlled to achieve a ductility enhancement effect similar to that of the present invention.

[0036] The honeycomb-confined high-ductility compressive yield concrete member of the present invention forms real-time compressive constraint on the ECC matrix through the transverse active shrinkage effect of the honeycomb skeleton with negative Poisson's ratio effect.

[0037] The cross-sectional shape of a single cell in a honeycomb structure is a concave hexagon, exhibiting a negative Poisson's ratio effect, with a negative Poisson's ratio (-0.3 to -0.08). When the component is subjected to axial compression, it undergoes lateral contraction.

[0038] The honeycomb-constrained high-ductility compressive yield concrete member of the present invention utilizes a cement matrix (such as ECC) to fill the honeycomb skeleton and integrally consolidate it. Under axial compression, the inward retraction of the inclined butt plates of the negative Poisson's ratio honeycomb skeleton causes the cement matrix to be subjected to lateral compressive constraint, thereby forming an active constraint force that is synchronously enhanced with the external load, which is different from the passive constraint of traditional external stirrups or sleeves.

[0039] This active constraint significantly inhibits the lateral expansion of the cement matrix and the propagation of internal microcracks, resulting in an ideal three-segment curve for the stress-strain relationship: a linear elastic segment; a yield-rising segment; and a gradual softening-falling segment.

[0040] Compared to unconstrained ECC members, the honeycomb-constrained high-ductility compressive yield concrete member of the present invention maintains a high bearing capacity while delaying the peak strain and gradually decreasing the post-peak stress, and the failure mode changes from brittle failure to progressive buckling failure.

[0041] The honeycomb-confined high-ductility compressive yield concrete member of the present invention can form an adjustable coupled design system based on negative Poisson's ratio honeycomb geometric parameters and cement matrix strength grade, so that the performance of the member can be quantitatively predicted and directionally optimized.

[0042] The angle between the adjacent plate and the obliquely mating plates on its two layers is defined as the reentry angle θ. In a preferred embodiment, the reentry angle θ between the adjacent plate 1111 and the obliquely mating plate 1112 is 60°~75°.

[0043] The relative density of cellular unit cell 111 is 0.15~0.35.

[0044] Specifically, the formula for calculating the relative density of cell 111 is as follows: , Where a is the width of the adjacent plate; b is the width of the beveled joint plate; t is the thickness of the sheet metal; θ is the angle of reentry.

[0045] The width of adjacent plate 1111 is 15~30mm. The width of beveled plate 1112 is 8~15mm.

[0046] The preferred materials for preparing the honeycomb skeleton of the honeycomb-confined high-ductility compressive yield concrete member of the present invention are ABS and PA6.

[0047] The geometric parameter design range of the honeycomb-confined high-ductility compressive yield concrete member of the present invention is as follows: Re-entry angle θ: 60°~75°; The relative density ρ of a negative Poisson's ratio honeycomb unit cell is 0.15–0.35. Width of adjacent plates: 15mm~30mm; Width of the beveled butt plate: 8mm~15mm.

[0048] The design principles and coupling mechanism of the honeycomb-confined high-ductility compressive yield concrete member of this invention: When θ and ρ are within the aforementioned ranges, the yield plateau can be extended and ductility improved to some extent. The strength grade of the cement matrix interacts with the θ and ρ parameters. The higher the strength grade of the cement matrix, the higher the bearing capacity of the compressive yield block, but the post-peak ductility will decrease.

[0049] The aforementioned adjustable coupling design system uses the geometric parameters of the negative Poisson's ratio honeycomb skeleton and the material strength grade of the cement matrix as coordinateable design variables to achieve quantitative prediction and directional optimization of the mechanical properties of the components.

[0050] To achieve a match between the negative Poisson's ratio honeycomb skeleton and the cement matrix in terms of mechanical properties, the present invention preferably uses PA6 or ABS as the material for the honeycomb skeleton and prepares it by 3D printing.

[0051] PA6 material has higher tensile strength (≥70 MPa) and elongation at break (>60%), and can achieve better peak delay when deformed under compressive coupling with the ECC matrix.

[0052] ABS material has good moldability and economy, making it suitable for general engineering scenarios.

[0053] Components constrained by a PA6 honeycomb skeleton exhibit significantly enhanced ductility and smoother post-peak softening, demonstrating superior performance.

[0054] The honeycomb-confined high-ductility compressive-yielding concrete member of this invention features a honeycomb skeleton that actively contracts laterally under compression, providing constraint on the cement matrix from the initial stage of stress. This active constraint effect is significant, resulting in a substantial improvement in member ductility and a significant delay in post-peak softening. Compared to traditional concrete members, the honeycomb-confined high-ductility compressive-yielding concrete member of this invention exhibits a significantly slower rate of post-peak stress decline, maintains high load-bearing capacity in the post-peak stage, and demonstrates significantly improved ductility, thus solving the problem of severe post-peak softening associated with existing constraint methods.

[0055] The honeycomb-confined high-ductility compressive yield concrete member of the present invention can achieve precise performance control through the geometric parameterization design of the honeycomb skeleton.

[0056] The honeycomb skeleton of the honeycomb-confined high-ductility compressive yield concrete member of this invention can flexibly control the confinement strength and deformation capacity by adjusting key parameters such as the reentry angle θ, relative density ρ, and plate thickness t (adjacent plates, oblique butt plates, and interlayer plates). This allows for performance matching of members with different strength grades, enabling precise determination of member performance during the design phase. Through the synergistic design of geometric parameters, the strength grade of the cement matrix, and the honeycomb skeleton preparation material, the post-peak plateau level and ductility range can be pre-set during the design phase. This facilitates the on-demand configuration of yield blocks in structural engineering, achieving predictable energy dissipation and ductility control.

[0057] This invention provides a construction method for honeycomb-confined high-ductility compressive yield concrete members, comprising the following steps: S1. Preparation of a honeycomb skeleton with a negative Poisson's ratio effect 1.

[0058] Based on the compressive performance requirements of the target component, the geometric parameters of the honeycomb skeleton are determined, including the width 'a' of adjacent plates, the width 'b' of obliquely joined plates, the thickness 't' of the members, and the reentry angle 'θ'. A honeycomb unit cell model is created using 3D modeling software, generating a periodically arranged honeycomb skeleton. After modeling, the honeycomb skeleton is printed using PA6 or ABS as raw material using 3D printing equipment. After printing, the honeycomb skeleton undergoes dimensional checks, surface deburring, and leveling to ensure the accuracy and overall stability of the honeycomb structure.

[0059] S2. Place the honeycomb skeleton 1 into the mold.

[0060] The printed honeycomb skeleton is placed in the designated position of the mold, and fixed brackets or support plates are used to prevent it from shifting during the casting process.

[0061] S3. Pour cement matrix 2 into the mold. Cement matrix 2 covers the honeycomb structure to solidify and form a honeycomb-confined high-ductility compressive yield concrete member.

[0062] First, prepare the cement matrix.

[0063] Prepare the cementitious matrix material according to design requirements. Commonly used proportions include cement, fly ash, silica fume, sand, water, water-reducing agent, and fiber. After thoroughly mixing the dry materials, add water and admixtures, and stir until a uniform fluid state is achieved. The prepared cement paste should have good fluidity and fiber dispersibility to ensure that it can fully coat the honeycomb structure during pouring.

[0064] Secondly, casting and shaping.

[0065] Slowly pour the prepared cement grout into the mold, ensuring it fully fills the pores and surrounding space of the honeycomb skeleton. Use vibration during pouring to remove air bubbles and ensure a tight bond between the honeycomb skeleton and the cement grout. The cement grout should cover the surface of the honeycomb skeleton, forming an integrated load-bearing structure. After pouring, keep the mold stationary, avoiding vibration or impact.

[0066] After casting, place the specimens in a standard curing environment for curing. Curing time is 28 days at room temperature, or steam curing can be used to accelerate strength development, depending on material requirements. During curing, humidity and temperature should be kept stable to prevent early shrinkage and cracking. After curing, demold the specimens, remove them, and inspect their dimensions, surface, and interface quality.

[0067] To further illustrate the performance of the honeycomb-confined high-ductility compressive yield concrete member of the present invention, the following examples and comparative examples are provided. Example

[0068] This embodiment provides a honeycomb-confined high-ductility compressive-yielding concrete member, wherein the geometric parameters of the honeycomb skeleton are as follows: The reentry angle θ of the cell is 60°. The relative density ρ of the cell is 0.25, the width of the adjacent plate is 25 mm, and the width of the oblique plate is 14 mm.

[0069] The honeycomb skeleton is made of ABS.

[0070] The cementitious matrix uses ECC with a strength of E30. The water-cement ratio of the ECC is 0.27, and the volume fraction of polyethylene fibers is 1.2%. Example

[0071] This embodiment provides a honeycomb-confined high-ductility compressive-yielding concrete member, wherein the geometric parameters of the honeycomb skeleton are as follows: The reentry angle θ of the cell is 60°. The relative density of the cell is ρ = 0.25, the width of the adjacent plate is 25 mm, and the width of the oblique plate is 14 mm.

[0072] The honeycomb skeleton was prepared using PA6.

[0073] The cementitious matrix uses ECC with a strength of E30. The water-cement ratio of the ECC is 0.27, and the volume fraction of polyethylene fibers is 1.2%.

[0074] Comparative Example 1 This comparative example provides a concrete component that differs from Example 1 only in that it does not have a honeycomb skeleton and is formed by casting with ECC cement matrix of strength E30.

[0075] The component specimens prepared in Examples 1 and 2, as well as Comparative Example 1, were tested after 28 days of curing.

[0076] The specimen is rectangular in shape, with dimensions of 150mm × 75mm × 75mm.

[0077] Performance testing methods for specimens: A uniaxial compression test was conducted using a 2000KN hydraulic servo testing machine (loading rate 0.3 mm / min). The stress-strain curves were recorded, and the peak stress, peak strain, ultimate stress, and ultimate strain were extracted.

[0078] For the uniaxial compressive stress-strain curves of specimens in Examples 1 and 2, and Comparative Example 1, please refer to [reference needed]. Figure 7 As shown.

[0079] The honeycomb-confined high-ductility compressive-yielding concrete member of the present invention achieves active restraint in the early stages of compression by introducing a honeycomb skeleton with a negative Poisson's ratio effect. The honeycomb cells in the honeycomb skeleton generate lateral active shrinkage during compression, which can form an effective confinement force in the early stage of loading, thereby delaying post-peak softening and improving overall ductility.

[0080] The honeycomb skeleton of the honeycomb-confined high-ductility compressive-yield concrete component of this invention is formed in one step using 3D printing technology and integrally cast with the cement matrix to form a composite structure, eliminating the need for external cladding construction and subsequent assembly. This integrated manufacturing method ensures strong interface bonding, good structural continuity, and high manufacturing efficiency.

[0081] The honeycomb-confined high-ductility compressive-yielding concrete member of this invention combines the high ductility of the ECC cement matrix with the active confinement characteristics of the negative Poisson's ratio honeycomb skeleton, forming a multi-level stress system that integrates materials and structure on a macroscopic level. During loading, this system can coordinate the deformation of the ECC matrix and the honeycomb lattice, resulting in a more uniform stress distribution and significantly improved post-peak ductility and structural stability.

[0082] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A honeycomb-confined high-ductility compressive-yielding concrete member, characterized in that, include: A honeycomb framework with a negative Poisson's ratio effect, wherein the Poisson's ratio of the honeycomb framework is -0.3 to -0.08, the honeycomb framework includes multiple unit cell structures arranged in the same direction, each unit cell structure includes multiple honeycomb unit cells in the shape of concave hexagonal prisms, each honeycomb unit cell includes two adjacent plates arranged opposite each other, and oblique butt plates are formed by extending inward from the opposite sides of the adjacent plates to the middle of the adjacent plates. The oblique butt plates on the same side of the two adjacent plates are connected, and the adjacent plates of two adjacent honeycomb unit cells in each unit cell structure are connected together. An interlayer plate is connected between the connection points of the two oblique butt plates in two adjacent unit cell structures. A cement matrix is ​​used to encapsulate the honeycomb structure.

2. The honeycomb-confined high-ductility compressive yield concrete member according to claim 1, characterized in that, The honeycomb skeleton is made of ABS or PA6 material.

3. The honeycomb-confined high-ductility compressive yield concrete member according to claim 2, characterized in that, The reentry angle between the adjacent plate and the oblique butt plate is 60°~75°.

4. The honeycomb-confined high-ductility compressive yield concrete member according to claim 3, characterized in that, The relative density of the cellular unit cells is 0.15~0.

35.

5. The honeycomb-confined high-ductility compressive yield concrete member according to claim 4, characterized in that, The width of the adjacent plate is 15~30mm, and the width of the oblique butt plate is 8~15mm.

6. The honeycomb-confined high-ductility compressive yield concrete member according to claim 2, characterized in that, The cement matrix is ​​ECC, UHPC, FRC or SCC.

7. The honeycomb-confined high-ductility compressive yield concrete member according to claim 2, characterized in that, The honeycomb skeleton was formed by 3D printing.

8. A construction method for a honeycomb-confined high-ductility compressive-yielding concrete member as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Prepare a honeycomb framework with a negative Poisson's ratio effect; The honeycomb skeleton is placed inside the mold; A cement matrix is ​​poured into the mold, and the cement matrix covers the honeycomb structure to solidify and form a honeycomb-confined high-ductility compressive-yield concrete member.

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